The Bryozoan Adeonellopsis in the Paleogene of the Southeastern United “'States

Louisiana State University LSU Digital Commons

LSU Historical Dissertations and Theses Graduate School

1971 The rB yozoan Adeonellopsis in the Paleogene of the Southeastern United States. Noland Embry Fields Jr Louisiana State University and Agricultural & Mechanical College

Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses

Recommended Citation Fields, Noland Embry Jr, "The rB yozoan Adeonellopsis in the Paleogene of the Southeastern United States." (1971). LSU Historical Dissertations and Theses. 2122. https://digitalcommons.lsu.edu/gradschool_disstheses/2122

This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. I I

72-17,760

FIELDS, Jr., Noland Embry, 1933- THE BRYOZOAN ADEONELLOPSIS IN THE PALEOGENE OF THE SOUTHEASTERN UNITED “'STATES.

The Louisiana State University and Agricultural and Mechanical College, Ph.D., 1971 Paleontology

University Microfilms, A XEROX Company, Ann Arbor, Michigan The Bryozoan Adeonellopsls in the Paleogene of the Southeastern United States

A Dissertation

Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy

The Department of Geology

by Noland Embry Fields, Jr.

B.A. University of Tennessee, 1955 M.S. University of Tennessee, I960

December, 1971 PLEASE NOTE:

Some pages may have

indistinct print.

Filmed as received.

University Microfilms, A Xerox Education Company ACKNOWLEDGEMENTS

The author gratefully acknowledges the help received from many individuals during this study. I am especially indebted to Dr. A. H. Cheetham, Curator, Department of

Paleobiology, National Museum of Natural History, the Smith sonian Institution, Washington, D.C. and Consulting Professor of Geology, Louisiana State University, for his supervision, criticism, counsel and concern. Dr. Cheetham gave freely of his time, assisted the author in field work, and made avail able study materials from the Smithsonian collections.

Sincere thanks are due Dr. H. V. Andersen, Dr. W. A. van den Bold, Dr. C. 0. Durham, Dr. G. F. Hart and Dr. J. P.

Morgan of Louisiana State University for manuscript review and several helpful suggestions. I also express my apprecia tion to Mr. C. J. Bangert and Mr. James Frane of the Computa tion Center, University of Kansas, for assistance concerning the NT-SYS programs and the use of computer facilities of that institution. Helpful assistance in data preparation was given by Dr. Thomas Madron of the Computer Center, Western

Kentuoky University. I also extend special thanks to Mrs.

Mary Ann McCelvey who typed the manuscript.

I sincerely acknowledge the encouragement and support provided throughout much of this study by the late N. E. Fields, Memphis, Tennessee, the late G. E. Haught, Tuscaloosa,

Alabama, and the late M. E. Byrd, Baton Rouge, Louisiana.

Finally, I am most indebted to my wife, Ann, for help in innumerable small ways, preliminary typing and encouragement. TABLE OF CONTENTS

PAGE

' ACKNOWLEDGEMENTS...... ii

LIST OF TABLES ...... vi

LIST OF ILLUSTRATIONS ...... vii

ABSTRACT ...... ix

INTRODUCTION ...... 1

SPECIES CONCEPTS ...... 6

PREVIOUS STUDIES ...... 10

PROCEDURE ...... 12

SAMPLING UNITS ...... 14

MORPHOLOGIC CHARACTERS ...... 21

General Relationships ...... 21

Zooecial Characteristics ...... 27

Frontal Wall Relationships ...... 30

Gonoecial Characteristics ...... 39

Quantitative Characters ...... 40

PHENETIC COMPARISON ...... 63

PHYLOGENY AND TAXONOMY ...... 82

General Relationships ...... • 82

Phylogenetic Relationships ...... 84

SUMMARY AND CONCLUSIONS ...... 94

SYSTEMATICS ...... 97

BIBLIOGRAPHY ...... 114 V

PAGE

APPENDIX ...... 120

Regional Geology ...... 121

General Lithologic Descriptions ...... 129

Sample Locations ...... 133

Initial Data M a t r i x ...... 143

PLATES ...... 147 LIST OF TABLES

TABLE PAGE

I Sampling Units ...... 16

II A Zooeclal Varlates ...... 43

II B Gonoecial Varlates ...... 47

III Morphologic C h a r a c t e r s ...... 65 LIST OF ILLUSTRATIONS

PAGE

1 Map of a Portion of the Southeastern United States and Sample Collection Area ...... 5

2 Distribution of Zoarial Fragments in Sampling U n i t s ...... 20

3 Generalized Adeonellopsls Zooecia...... 23

4 Diagrammatical Representation of Ontogenetic Changes in Adeonellopsls ...... 35

5 Diagrammatical Representation of an Adeonellopsls Colony Fragment • ...... 38

6 Histogram of Standard Measurements for Zooecia and Gonoecia, Sampling Unit 9 . . . 42

7 Histogram Summaries of Coefficient of Variation Data for Z o o e c i a ...... 53

8 Histogram Summaries of Coefficient of Variation Data for Gonoecia ...... 55

9 Scatter Polygons for Mean Zooecial D i m e n s i o n s ...... 57

10 Scatter Polygons for Mean Gonoecial D i m e n s i o n s ...... • 59

11 Scatter Polygons for Mean Zooecial Oral Dimensions ...... 61

12 Dendrogram from Correlation Coefficient Matrix WPGM ...... 71

13 Dendrogram from Correlation Coefficient Matrix UPGM ...... 73

Dendrogram from Taxonomic Distance Matrix WPGM ...... 75

Dendrogram from Taxonomic Distance Matrix UPGM ...... 77 viii

FIGURE PAGE

16 Dendrogram from Correlation Coefficient Matrix WPGM ...... 80

17 H Contour Map” of Phene tic Cl u s t e r s ...... 87

18 Inferred Phylogenetic Relationships of Adeonellopsls ...... 90

A1 General Correlation Chart for Lithostratigraphic Units ...... 124

A2 Eocene-Oligocene Facies Relationships in Study A r e a ...... 127

PLATE

I Adeonellopsls magnlporosa...... 149

II Adeonellopsls magnlporosa...... 151

III Adeonellopsls transverse...... 153

IV Adeonellopsls qulsenberryae...... • • • 155

V Adeonellopsls c y c Io p b X ...... 157

VI Adeonellopsls cvolops cvclops ...... 159

VII Adeonellopsls cvclops -cvclops...... 161

VIII Adeonellopsls galeata ...... 163

IX Adeonellopsls galeata ...... 165 ABSTRACT

In many of the Eocene and Oligocene bryozoan faunules of the central Gulf Coastal Plain the adeonid genus Adeonellopsls is a frequent and distinctive member.

It is one of numerous taxa which vary throughout the regional Tertiary sequence both qualitatively and quanti tatively as a result of evolutionary and ecologic influ ences. Distinctive zooecial and gonoecial structures make the species of Adeonellopsls obvious epifaunal components in the regional thanatocoenose assemblages but significant morphologic variation within and between populations as well as striking ontogenetic changes preclude a morphospe- cles approach to species determination as well as a monothetic classification scheme.

This investigation of population characteristics and speciation in Adeonellopsls emphasizes evolutionary aspects of the species to evaluate morphology and establish taxa consistent with the biospecles concept. Inconsistencies in morphologic description and inadequate consideration of intra-colony and inter-population variation typified earlier morphospecific studies. A suite of samples from the Gulf

Eocene-Oligocene outcrop belt provided specimens for the study and these were supplemented by studies of type speci mens in the National Museum of Natural History. X

Approximately 150 samples were organized into 33 sampling units. A morphologic study was made on numerous individuals in each unit in order to recognize genetically controlled variation and the sources of extragenetlc varia tion in this cheilostome complex. A ‘biometric evaluation of 44 quantitative and qualitative characters inferred to be genetically based was also completed to establish the intra-colony, geographic, and stratigraphic distribution of these features. This information was summarized in code form in a data matrix for manipulation with a series of multivariate statistical procedures. Data analysis was completed by digital computer using standard techniques in numerical taxonomy to cluster related samples.

Interpretation of this Information established five polythetically derived, phenetic clusters which were con sidered with their distributional data to make phylogenetic inferences and taxonomic groupings. Relationships were brought out indicating similarities among what had been con sidered distinct species of Adeonellopsls. Five species were delimited by these methods, identified with name-bearing specimens, and incorporated in a phyletic classification.

One new subspecies was recognized. INTRODUCTION

In many of the Eocene and Oligocene bryozoan faunules of the central Gulf Coastal Plain, the adeonid genus

Adeonellopsls Is a frequent and distinctive member. Adeonel- lonsis is one of numerous taxa which vary throughout the regional Tertiary sequence both qualitatively and quantita tively as a result of what have been considered non-directional or ecologlc influences and directional or evolutionary influ ences (Cheetham and Deboo, 1963). Selected area faunas have been evaluated in terms of biogeography, biostratigraphy, paleoecology or systematics by several recent workers (Bandy,

1949; Gardner, 1937; Cheetham, 1963; Deboo, 1965; Park, 1968;

Glawe, 1969; and Hazel, 1970).

Where preservation is adequate, zooecial structures such as a stellate ascopore, a "hooded" peristome and promi nent suboral avicularia displayed In erect, bifoliate zoaria make the species of Adeonellopsls obvious components of the epifauna in the regional thanatocoenose assemblages. However, significant morphologic variation within and between popula tions precludes any monothetic classificatory scheme. Such an approach could thus obscure the pattern of evolutionary and ecologlc variation. Also, ontogenetic changes within colonies are striking and Induce additional variation that must be explained. These factors make Adeonellopsls an ideal 2

subjeot for Investigation of population variation and specia-

tion. Although complete zoaria are rare, numerous colony

fragments exhibit sufficient zooecial variation which over

laps between different fragments so that interpretation and

evaluation of these morphologic and ontogenetic relationships

can be made.

An extensive, but largely descriptive, study of Terti ary chellostomes and oyclostomes in the southeastern United

States was completed by Canu and Bassler (1920) who described

seven species of Adeonellopsls. Some of these taxa appear

superficially discrete, but overlap in various morphologio

characters among the named species, the presence of intricate

character interrelationships and the polytypic nature of some

groupings is apparent. Many aspects of this early work in

cluding a morphospecific approach to species determination,

inconsistencies in description of morphology and inadequate

consideration of intracolony and intrapopulation variation raise questions concerning the validity of the segregations previously made in this Adeonellopsls complex.

The purpose of this study is to investigate Adeonel-

lopsls in a part of the Gulf Tertiary sequence, emphasizing

the evolutionary aspects of the species to evaluate morphology

and establish appropriate groups for taxonomy. The comments

of Barnes (1968), Beerbower (1968) and Moore et al. (1968)

are representative of opinion which cites a general lack of

suoh detailed studies on both modern and fossil bryozoans.

House (1971) even completely eliminates the Bryozoa from his evaluation of evolution and the fossil record. This present investigation required a review of previous determina tions made with respect to these fossils plus a detailed sur vey of population samples from new field collections. Also required was a review of both practical and theoretical is sues relating to the concept of the species category in order to outline factors for consideration and set up appropriate guidelines for classification revisions.

Figure 1 shows the regional Eocene-Oligocene outcrop belt from which samples were obtained to support the study.

Numerical methods were employed to analyze the various quali tative attributes of zooecia, gonoecia and special structures and the distribution of these features in the population samples. FIGURE 1

Map of a portion of the southeastern

United States showing the area from which Paleogene samples of Adeonellopsls were collected. Details of localities are listed in appendix. ARK. ALA. GA.

GULF OF MEXICO

100 SPECIES CONCEPTS

In nature, there are diverse, but real contempo raneous populations of similar organisms which may or may not overlap In their geographic ranges. These groups ex hibit a general but variable likeness which Is a reflection of both basic genetic Identity among the Individuals and their adaptation to particular sets of environmental fac tors. Such assemblages are biological species or groups of actually or potentially Interbreeding natural populations reproductlvely isolated from other such groups (Mayr, 1940).

General variation In such a single reproductive community is accepted as an essentially inherent attribute of dynamic and changing populations. Gene flow as the cohesive force for such population units is considered restricted by Ehr- lich and Raven (1969) however, who stress the importance of the selective regime as the primary factor underlying patterns of similarity and difference.

The biologic speoles concept has general utility and objectivity for sexually reproducing organisms and it facilitates the ordering of related biologic arrays. Mettler and Gregg (1969) and Mayr (1963) discuss a variety of diffi culties however, which may limit, obscure or qualify the determination of such species. Not all investigators readily accept the basic tenets of the biospecies conoept. The comments of Ehrlich and Holm (1963) are typical of those who question the adequacy, utility and necessity of the con cept as well as hierarchic structures formally recognizing and Incorporating distinct species.

Another but more restricted approach to species de terminations depends on strong morphologic identity among individuals in a group and significant morphologic differ ences between groups. This approach is essentially a typo logical one and conceives species as somewhat invariant static entities. Such morphospecies designations may be widely applicable and provide for gross description of natural order (although such description would lack a historical ex planation), but this approach inhibits the determination of evolutionary lineages and causes problems in supraspeciflc classification, particularly if a polythetic evaluation is sought. Consequently, investigation of species problems usually indicates that the variable population is the basic unit for evaluation and interpretation. The significance of the population for paleontological analysis has been dis cussed by Newell (195A). Mettler and Gregg (1969) point out, however, that for the related problems of description and classification of organic diversity and the conoept and rec ognition of species there is no tidy answer.

Species problems are no less real for paleontology, but their interpretation and resolution frequently are more involved as morphologic gradients and other population char acteristics can often be analyzed along essentially one time surface or over several succeeding horizons. Simpson's

(1961) evolutionary species concept Is tied to "a lineage

(an ancestral-descendent sequence of populations) evolving separately from others and with Its own evolutionary role and tendencies." The biospeoies definition applies to this evolutionary concept in terms of population relationships at any point on a single lineage as best they can be established on the basis of phenetic relationships (Sokal and Sneath,

1963) and other parameters. Segregation of a relatively un broken temporal sequence of populations arrayed as a single

Inferred lineage is subjective and diffioult, however. Thus, a paleontological species with respect to the evolutionary concept is considered as an arbitrarily delineated sequence of ancestral-descendent populations which constitute a seg ment of a single lineage. Such entitles are successional speoies (Imbrle, 1957) or paleospecies (Cain, 1954) or chrono- species (Thomas, 1956). As George (1956) Indicates, a chrono- species represents an extension of a static, biologically conceived species into time. Paleontologists try to estab lish for such species the variation that would be associated with a true genetic spatial-temporal population.

Morphological studies are neoessary for employment of either the chronospecles or morphospecies concept, but rigid morphological division of fossil populations establishes speoies which have limited value for stratigraphy, create nomenclatural problems, obscure natural variation and inhibit kinship inferences. The chronospeoies, as a paleontological biospecies, best approximates a true blospecles because the concept on whioh it is based recognizes species as dynamic, evolving population systems which demonstrate the variations and gradients anticipated in genetic systems. There are, however, no universal guidelines relating to what constitutes sufficient distinction for discrimination of species taxa in such a continuum, although decisions are usually based on some criteria indicative of reproductive isolation.

Despite recent criticism by Shaw (1969) concerning the objectivity of paleontological species and certain goal- oriented approaches to paleospecies determination, and Cain*s comment (1954) that "a species is whatever a competent sys- tematist says it is," the species concept is a central one for systematics in paleontology as it is in neontology. As

Boardman, Cheetham and Cook state (1969), the species and the population through their direct relation to gene pools are the fundamental categories through which phylogenetic patterns may be realized and utilized for supraspecific classi fication. PREVIOUS STUDIES

Apparently using a morphospeoies approach, Canu and

Bassler, in their 1920 monograph on North Amerioan Early

Tertiary Bryozoa, described seven species of Adeonellopsls from beds of Wilcox, Claiborne, Jackson and Vicksburg age

In Alabama and Mississippi. Quantitative and qualitative variation In these ohellostomes make such an approach largely an unsatisfactory one. Beyond a general recognition of the presence of variation, no attempt was made to analyze differences systematically with respect to colony growth and population distribution.

Morphological gaps appear to be present between

"species" with regard to certain features, but subtle dif ferences and gradients among many other characteristics are noticeable. For example, the stellate ascopore described by Canu and Bassler as a more or less common character for all assemblages represents only one state for the ascopore which varies from rounded to incompletely stellate to stel late.

Also, character combinations are not uniform within these previously established taxa and overlap exists with respect to many morphological features between them. Diag nostic characters of A. c.volops as given in original descrip tions are a distal pore or avicularium on the peristome and 11 distinct marginal zooecia; yet these phenomena are present

In some colonies of three other species.

Ontogenetic changes and sexual dimorphism were In completely known previously and not effectively evaluated.

For example, the ordinary zooecia of A. grandIs have been thought to lack a cribriform ascopore area, but this char acter appears to be a function of ontogeny. Similarly, the cribriform area of A. aulsenberrvae was regarded as uniporous externally and multiporous internally. Older zooeoia of this taxon (and others) do often exhibit a "single ascopore" where the frontal wall has closed over the top of the multi porous ascopore, but younger zooecia do not show this rela tionship, Fragments of A. cyclops exhibit well developed gonoecia, but Canu and Bassler included no discussion of their characteristics.

This present study, in addition to the analysis of variation and character combinations, attempts to describe various morphologic features more precisely and consistently. PROCEDURE

In order to evaluate some of the morphologic and taxonomic relationships in Adeonellopsls. it was necessary to study blometrically a large number of morphologic fea tures on many individuals and establish their intracolony, geographic and stratigraphic distributions. The primary basis for the study is a suite of samples collected in the

Eocene-Oligocene outcrop belt from northern Florida to

Louisiana. To supplement observations from these samples and to put them into a formal systematic framework, the type specimens named by Canu and Bassler were studied in the De partment of Paleobiology, National Museum of Natural History, the Smithsonian Institution.

The majority of the approximately 150 samples obtained were collected during 1967. The samples were disaggregated without difficulty and dry residues coarser than 0.50 mm. were picked. Cursory inspection of finer fractions disclosed only negligible bryozoan fragments. Roughly half the samples contained Adeonellopsls fragments.

Poorly preserved specimens and specimens showing re stricted ontogenetic stages were not used in further analyses.

Samples with small numbers of specimens and closely spaced samples in certain areas were combined to form appropriate

"sampling units" for detailed examination. Speoimens were 13 studied with a Wild M-5 stereomicroscope equipped to allow magnifications up to 100 X and measurements were made with an eyepiece reticle. Routine statistical computations were made with a Friden electronic desk calculator.

Where possible, varlates were observed on 20 zooecia and 10 gonoeoia in each sampling unit. Subject to sampling unit limitations, zooecial observations were deployed over

10 zoarial fragments and gonoecial observations were made on 5 zoarial fragments. In all, some 20,000 discrete bits of information were obtained.

This information was summarized in code form in an initial data matrix for subsequent manipulation with a series of multivariate statistical procedures. Data analysis was completed by a Honeywell Model 635 digital computer at the

University of Kansas Computation Center using the NT-SYS programs of that institution to standardize the initial matrix, compute correlation and distance matrices and cluster related samples.

Photographs were made with a Wild MKal camera attached to the microscope. The photographs are not retouched, but the specimens were coated with colored dye to accentuate re lief and provide contrast. Figured specimens will receive

USNM numbers and a reference collection will be placed in the

Louisiana State University Geology Museum. SAMPLING UNITS

The portion of the geologic record examined for this investigation consists primarily of Eocene-Oligocene strata in the central and east-central Gulf Coastal Plain where marine facies are most extensively exposed. Sedi ments of this age change laterally from predominantly car bonates in Florida and southeastern Alabama to limestones, marls and clays in southwestern Alabama and eastern Mis sissippi and finally to sands and clays farther west in Mis sissippi and Louisiana (Deboo, 1965). A general discussion of regional geology and stratigraphlc relationships is ap pended.

A total of 153 samples were obtained from 42 sepa rate locations throughout this area. Specific localities investigated are listed in the appendix and the particular samples containing Adeonellopsls are designated. To supple ment 133 field samples, 20 additional samples (localities designated by letter in appendix) were obtained from the collections of the Louisiana State University Geology

Museum and the National Museum of Natural History, the

Smithsonian Institution. Examination of these materials disclosed that 67 samples or 44 percent of the total sample collection contained specimens of Adeonellopsls.

In order to overcome some of the limitations imposed by sample size and preservation and to more effectively organize the specimens for numerical analysis, many samples from similar stratigraphio and geographic positions were grouped to form suitable "sampling units." In certain

Instances, no such grouping was possible because no similar samples from nearby locations were available or because the need for data from a particular location, however limited, was paramount to providing for the desired number of observa tions through a grouping procedure. In all, 33 sampling units were established to serve as a basis for further study.

Table I shows each of these units, the samples which compose them and the stratigraphlc interval represented.

The enclosed figures adjacent to each sample indicate the number of usable fragments. Figure 2 shows the distribution of zoarial fragments for each sampling unit. A grand total of about 3500 colony fragments were recovered. 16

TABLE I SAMPLING UNITS

Unit Sanroles StratiKranhic Data

1. 15ABa 01 (5) Bashi Marl; Butler, Alabama. S3 Ba 01 (11)

2. SI Li 01 (3) Lisbon Fm.; Little Stave Creek, Alabama.

3. 7 Go 01 (20) Lower and Upper Gosport Sand; 16 Go 01 (2) Little Stave Creek and Claiborne SI Go 01 (1) Bluff, Alabama. SI Go 02 (3)

3A. Same as 3 (6) Same as 3.

4. G Da 01 (5) Danville Landing Beds; Louisiana.

5. A Co 01 (12) Cooper Marl; Georgia.

6. 18 Pa 01 (1) Basal Pachuta Marl; St. Stephens, Alabama.

7. SI Sh 01 (3) Upper Shubuta Clay; Little Stave S2 Sh 01 (5) Creek and St. Stephens, Alabama.

8. 13 RB 01 (31) Basal Red Bluff Clay; West Alabama

9. 16 RB 01 (42) Basal Red Bluff Clay; Little Stave 18 RB 01 (21) Creek and St. Stephens, Alabama. 18 RB 02 (33)

10. 16 RB 02 (61) Middle Red Bluff Clay; Little 18 RB 03 (37) Stave Creek and St. Stephens, Alabama.

11. 6 RB 01 (21) Upper Red Bluff Clay; Perdue Hill 17 RB 01 (7) and Suggesville, Alabama.

12. 16 RB 03 (53) Upper Red Bluff Clay; Little Stave 18 RB 04 (41) Creek and St. Stephens, Alabama 18 RB 05 (60) and Hiwannee, Mississippi. E RB 01 (3)

13. 1 Ma 01 (22) Basal Marianna Limestone; Florida.

14. 16 Ma 01 (14) Basal Marianna and Upper Mint 16 Ma 02 (8) Spring Marl; Little Stave Creek, 16 MS 02 (12) Alabama. 17 TABLE I. Continued

Unit Sample Stratlgraphlo Data

15. 16 MS 01 (56) Basal and Middle Mint Spring Marl; 16 MS 03 (7) Little Stave Creek, Alabama.

16. 6 Ma 01 (30) Basal Marianna Limestone; Perdue 17 Ma 04 (6) Hill and Suggesville, Alabama.

17. 17 Ma 03 (11) Middle Marianna Limestone; Suggesville, Alabama.

18. 14 Ma 01 (26) Middle Marianna Limestone; St. 18 Ma 01 (10) Stephens and Salt Mountain, 18 Ma 02 (14) Alabama.

19. 19 Ma 02 (11) Middle Marianna Limestone; Bucatunna 20 Ma 03 Creek, Waynesboro and Sylvarena, 24 Ma 01 (14) Mississippi.

20. 3 Ma 01 (10) Upper Marianna Limestone; Florida.

21. 5 Ma 01 (11) Upper Marianna Limestone; Frisco 17 Ma 01 (10) City, Monroeville and Suggesville, 17 Ma 02 (15 Alabama. C Ma 01 (17)

2 2 . 16 Ma 03 (3) Upper Marianna Limestone; Little 18 Ma 04 (25) Stave Creek and St. Stephens, 18 Ma 05 (7) Alabama.

23. 20 Ma 01 (10) Upper Marianna Limestone; 20 Ma 02 (14) Waynesboro, Mississippi. 24 Ma 02 (11)

24. 5 G1 01 (5) Basal Glendon Fm.; Frisco City B G1 01 (18) and Escambia County, Alabama.

25. 23 G1 01 Basal Glendon Fm.; Heidelberg 26 G1 01 (3) and Brandon, Mississippi.

26. 31 G1 02 (1) Middle Glendon Fm.; Vicksburg, Mississippi.

27. 5 G1 02 (50) Upper Glendon Fm.; Frisco City and St. Stephens, Alabama and 18 G1 01 6 ! 24 G1 01 1 Sylvarena, Mississippi. 18

TABLE I. Continued

Unit Samples Stratigraphlc Data

28. P By 01 (10) Middle Byram Marl; Byram, Mississippi.

29. D By 01 (31) Middle Byram Marl; Castleberry, Alabama.

30. SI MB 01 (l) Basal Moodys Marl; Little Stave 54 MB 01 (5) Creek and Claiborne Bluff, Alabama.

31. 55 MB 01 (3) Moodys Marl; Jackson, Mississippi.

32. 56 Bu 01 (1) Crystal River and Bumpnose 57 CR 01 (l) Limestones; Florida. S7 CR 02 (1 S7 Bu 01 (3 19

FIGURE 2

Bar graph showing distribution of usable zoarial fragments in sampling units. Usable fragments Include all those from which some information is obtainable, even though every such fragment may not be suitable for detailed study. ZOARIAL FRAGMENTS 150 100 50 - 50 - 2 3 4 6 8 1 1 12 3 4 5 6 7 8 9 0 1 2 3 4 5 6 72 2 3 3 32 31 30 29 2728 26 25 23 24 22 21 20 19 18 17 16 15 14 1 13 2 11 10 9 8 7 6 5 4 3A 3 2 1 PLING UNITS G N I L MP A S MORPHOLOGIC CHARACTERS

General Relationships

The genus Adeonellopsls was established in 1886 by MacGillivray for those ascophorans having one or several ascopores in the median line of the frontal wall grouped at the base of a cribriform area and having interzooeclal avicularia and gonoecia. It is one of three adeonid genera which possess ascopores. Canu and Bassler (1920) followed Levin- sen (1909) in placing all species with stellate ascopores in this taxon.

Adeonellopsls. in addition to special characteris tics of the ascopore, which is frequently compound, exhibits well-developed gonoecia larger than zooecla, single or mul tiple sub-oral (and sometimes supra-oral) avicularia without pivots and is entirely marginally areolate. The areolae ex tend to or near the base of the zooecial vertical walls. In these respects, it is a typical member of the family Adeoni- dae Hlnoks. Figure 3 shows a number of these features and certain standard measurement symbols. The type species,

&• follacea MacGillivray, has small rhombic zooecia with several large, distally directed suboral avicularia terminat ing at the edge of the peristome and a oompound ascopore.

It generally resembles A. selsevensls Cheetham from the 22

FIGURE 3

Generalized Adeonellopala zooecia Bhowing aeveral major

featurea. Standard meaaurementa for zooecial length (Lz),

width (lz), oral length (ho), width (lo) and avicularian

length (Lav) are indicated. Similar meaaurementa (Lg, lg

etc.) are made for gonoecia. 0 AreoI a Oral Area

4 Subora I a Av IcuI a rIum A s c o p o r e $ Area A

ProxImaI v ' 1 . < 0 Avleu I ar Iu m Lz d

.25 L _J m m , 24

Sussex Eocene (Cheetham, 1966), but no similar forms have been observed In American deposits.

Specimens of the Adeonellopsls Gulf Tertiary stock were reviewed in detail to determine the nature of the morphologic features present and to select characters suit able for numerical analysis. As Boardman and Cheetham (1969) indicate, the high degree of organization of bryozoan indi viduals and colonies makes many phenetlc characters and character combinations available for taxonomic work. Morpho logic details considered for this investigation are primarily those of the complex, outer skeletal surface, chiefly the frontal wall and associated structures. A number of these same details were observed by Canu and Bassler in their early, important and expansive work (1920). Their general and limited discussion of them, however, plus the exclusion of other variates from their study points out the appropri ateness of Rogickfs criticism (1957) citing the partial and inadequate investigation of the external skeleton as well as soft parts in many studies of calcareous Bryozoa.

In the present study, both zooecial and gonoecial properties were directly discernible, but zoarial form was evaluated in part on the basis of previous studies and relationships exhibited by similar genera. No complete zoaria were found and only a few fragments Included colony basal areas or regions of branching. From a small encrust ing base, Adeonellopsls zoaria evidently develop a short, round stem-like region from which arise one or several narrow, bilaminate branches or fronds, which, although flat tened, are often slightly swollen or convex. Individual fronds may divide or rebranch in a dichotomous pattern.

Some of these erect, arborescent, adeoniform (Brown, 1952) colonies may reach a height of two centimeters (Canu and

Bassler, 1920). The growing edge of the colony is at the delicate, distal tips of the fronds. Here, and in immedi ately adjacent positions, the zooeoia are thin and fragile but older parts of the colony are typically heavier and more rigid as additional zooecial and zoarial skeletal matter formed by secretory membranes continues to thicken individual frontal walls and to obscure and occlude zooecia of early generations.

Numerous, somewhat rectangular zooecia about one- half millimeter in length are displayed in proximal-distal colony rows on each side of a lamina, with individual zooecia alternating in position with those of adjacent rows. Basal, lateral, and distal zooecial walls of "mature" individuals are thin, while the frontal wall is much thicker. All are formed by epithella associated with the zooid. The discrete zooecia are essentially box-shaped, although the frontal surface may not always appear as a basically rectangular

"box-top." Claviform, rhombic or lacrimal frontal aspects result from changes in relative positions of walls as they extend frontally. The box walls surround a similar box-like coelomic cavity containing the polypide. Correspondence between the zooecial and coelomic cavities is not quite 26 this exact, as the ascus is also included in the zooeoial cavity. Extension of the microphagous polypide is brought about by hydrostatic pressure of the coelomic fluid. A brief summary of the mechanics of extrusion and some of the attendant problems in ascophorans is presented by Barrington

(1967).

The variations in some of the characters and charac ter combinations exhibited throughout a bryozoan colony are often numerous and the interpretations of their origin, na ture and distribution may be as varied as the features them selves. Confusion and errors have resulted from improper or incomplete evaluation. The review of Boardman and Cheetham

(1969) provides a good conceptual basis for more effective consideration of such variations. As they state, the in dividuals of a bryozoan colony can be assumed to possess a uniform genotype, and thus genetic variation can be essen tially eliminated when evaluating morphologic differences among members of a single colony. As they further indicate, phenetic variation present can then be considered a function of colony astogeny, individual ontogeny, polymorphism and microhabitat. If these sources of intracolony variation can be recognized and appreciated, then the determination and isolation of genetically controlled phenetic variation in different colonies is possible.

Consequently, population phenetic studies of Bryozoa based on characteristics assumed to be genetically influ enced can be made. Appropriate use of such data can provide inherently suitable support for phyletlc inference. To be significant, however, such population studies must compare only comparable individuals from different colonies— that is, similar type zooecia at a similar stage of development oc cupying similar colony positions. Study of such individuals which represent equivalent ontogenetic, astogenetic, poly morphic and where possible microenvironmental stages is neces sary so that the range of morphology displayed by a species can be properly assessed. Otherwise, basic morphological and physiological differences between zooecia, heterozooecia and gonoecia in a colony plus other differences associated with age and position can induce distinctions of such magnitude that different fragments of the same genetic-ecologic oolony could in some circumstances be interpreted as different species. Also, variant individuals from many different colo nies may be incorrectly considered as separate entities for similar reasons, when in reality they should be considered oonspeclflc. Raup and Stanley (1971) stress the fundamental importance of ontogeny in the total description of an organ ism and in the interpretation of an evolutionary series of specimens which they describe as a "sequence of ontogenies."

Zooecial Characteristics

Marginal areolae completely encircle the zooecia of Adeonellopsls as they do in other adeonids and thus define the approximate limits of zooecia. In some instances the areolae are quite prominent. Although there is variation in 28 their basic shape, they are predominantly rounded or elongated.

Placed between them and the orifice-ascopore region is a com plete, thin and more or less elliptical ridge which forms the boundary of the "total area" or essentially the main, central part of the upper zooecial region in a marked fashion.

This conspicuous area may be elliptical in overall outline or taper proximally, and even though it may appear to form an important demarcation, it is only a part of the actual frontal surface.

A prominent triangular or elliptical suboral avicularium is present in Adeonellopsls specimens studied and its rostrum frequently is oriented in a distal or lateral direction. In some samples, the avicularium is placed on an oral "bridge" or support bar extending laterally across the proximal part of the oral area. This type of suboral avicu larium occupies a position in the proximal peristome region and may touch one of the parietal walls of the total area.

Just below or distal to this peristomial avicularium, a small, serrated tooth-like projection or oral denticle may appear on the bar. Other specimens exhibit a suboral avicularium completely removed from the oral area and placed in a center frontal position subjacent to it. Many zooecia display a large, rounded avicularium in a lateral or proximal position

(or both) along the line of marginal areolae. Such a marginal proximal avicularium may project above the frontal surface.

A rounded distal avicularium is also common on many Individuals, but it is often small and sometimes has the appearance of a 29 single distal pore. Occasionally, other adventitious avicu laria are present on the frontal wall.

The ascopore area in Adeonellopsls is a cribriform region usually somewhat depressed below the surface of the frontal wall and placed in a central position on the zooecium.

The average diameter of this area is about 0.075 mm. The number of openings in the ascopore area varies, but several are normally present. The openings are often stellate and in most cases quite small. This sieve-like structure opens into an ascus underlying the frontal wall in living species of Adeonellopsls. and the ascus can be inferred to have had a similar anatomical position in fossil species. The frontal wall does not seem to encroach conspicuously on the ascopore region until it is rather thiok. At this point, the ascopore occupies a sizeable depression in the enlarged frontal wall.

Such encroachment constricts the frontal end of the ascopore and as a result it appears uniporous on some individuals.

In older zooecia, a well-developed peristome is pres ent. This feature prevents observation of the primary ori fice, but the upper margins of the peristome define the semi circular or semi-elliptical secondary orifice. A few specimen

Interiors indicate that this orifice is similar in size and. shape to the primary one. In some specimens, the peristome margin is thinner or thicker than normal. A striking feature in many of the colonies lnspeoted is the distinctly "hooded" appearance of the peristome produced by an elevated, proximally 30 directed convexity forming and essentially capping the dis tal peristome margin.

Frontal Wall Relationships

The distinctive features displayed on the frontal surfaces of zooecia of Adeonellopsls are intimately related to the developmental changes in the frontal wall and its secreting epithelium. The calcareous frontal wall in Recent species of Adeonellopsls is secreted by an epifrontal mem brane internally connected to the endozooecial epithelium through marginal areolae. Calcification advances distally and medially from calcified lateral and transverse walls.

It has not been demonstrated whether the epifrontal membrane originates in the unbonuloid or lepralioid pattern (Harmer,

1902), but Harmer (1957) Implied that frontal wall formation for this genus is of the lepralioid type. Current work by

Cook (in preparation) is directed toward establishing the correct relationship.

Secretion of this upper calcareous wall apparently occurs on the basal side of the membrane and calcification ad vances toward the oral area. Calcification evidently proceeds behind the leading edge of this fold (Harmer, 1957). In some ascophorans, calcification may occur on the frontal side of this epifrontal outfolding of the body wall, but this has not yet been substantiated (Boardman and Cheetham, 1969).

When initially complete, this frontal shield is thin and without avicularia, although the ascopore is partly formed and marginal indentations or areolae are present. Based on observed fossil specimens, additional calcareous material seems to be added to this structure first along proximal and lateral zooecial margins, but subsequently accumulates more distally and medially. As the frontal surface oontinues to develop, areolae become more distinct, the suboral avic ularium forms, the ridge defining the total area originates and the ascopore becomes prominent. As wall thickening oc curs concomitantly in a frontal direction, a peristome is developed as well as a "channel" to the ascopore. Also, one or two rounded avicularia may form on the line of areolae, usually in a distal or proximal position.

As a consequence of continued addition of calcareous material on the frontal wall, occlusion and modification of frontal features occurs in older generation zooecia. Some marginal areolae in proximal and lateral regions and the rim and peripheral regions of the total area are often occluded early as skeletal matter is built over them. The total area ridge becomes indistinct as it merges with the enlarging upper wall. The suboral avicularium and avicularia on the line of marginal areolae may escape early occlusion. Nourishment of the secreting membrane evidently continues from unoccluded and distal areolae and from adjacent zoolds. Subsequently, the circular ascopore or ascopore "channel" becomes constricted and narrows appreciably as calcification advances across the upper part of it. Finally the secondary orifice and the suboral avicularium are occluded and most remaining areolae 32 are closed as calcification Increases distally. The frontal wall may continue to thicken but membrane nourishment is obtained solely from adjacent feeding zooids, When the suboral avicularium is incorporated within the peristome, it may not be modified until the secondary orifice itself is sealed. In many instances, the ascopore and orifice appear to be closed more or less simultaneously.

In some cases (often in A. magnlporosa) significant elevation of the lateral parts of the upper wall in a frontal direction forms a large space which inoludes both the ascopore and secondary orifice. As calcifioation continues medially across the top of the frontal wall, a circular entrance to the space originates but the unaltered ascopore and orifice remain visible through it. When this entrance is sealed, these structures are occluded, but they were not systematically altered in the process.

Many of these zooecial surface features change appar ently continuously throughout the development of the frontal wall. Significant in this respect are the thickening of the total area marginal ridge, the increasing peristome depth and the constriction of the ascopore and areolae. Certain early formed features such as avicularia and the secondary orifice do not seem subject to intensive continuous modification. The ascopore itself is also not appreciably modified as it is only the upper end of it (or the channel to it) which is gradually closed. 33

Thus in the ontogeny of the frontal wall, a thin, uniform surface of low relief develops early and it is largely devoid of distinctive structures. As accretion con tinues, a frontal surface of noticeable relief is formed and well-developed frontal features such as avicularia and an ascopore are prominent. Finally, as a result of significant calcareous additions to it, the frontal shield becomes a uniform low relief surface again without major structures, although a few areolae and marginal avicularia may remain.

In this late stage of development, the frontal wall is quite thick and the upper surface is somewhat undulate and convex.

Zooecial boundaries at this point are usually indistinct.

With the merger of epifrontal membranes and their secretions across zooid boundaries, zoarial tissues and skeletal matter originate (Boardman and Cheetham, 1969). The ontogenetic ohanges are summarized in Figure 4.

These relationships are noticeable over the colony ontogenetic gradient which is expressed distally to proximally.

The observations made for this study apply chiefly to "mature" zooecia developed along the central zone of such a gradient.

Initially developing zooecia at a colony distal margin were not observed, although young or "immature" zooecia evidently near this region were present in some samples. "Mature" zooecia are here characterized as those complete zooecia

(well-defined oral features, peristome, areolae and avicu laria) with a fully developed, moderately thick frontal wall which has not significantly enclosed the ascopore or occluded other major features. 34

FIGURE 4

Diagrammatical representation of ontogenetic changes in

Adeonellopsls (based on mode of representation in Boardman and Cheetham, 1969f Fig. 4). Median longitudinal sections above; transverse sections below. Progressive growth stages

(generalized) are indicated from right (distal) to left

(proximal). At stages 1 and 2 zooecia are complete, but the calcareous frontal wall is not appreciably thick. At stage

3, accretion on the frontal wall has thickened it and the upper end of the ascopore is constricted. Stage 4 shows an older zooecium with the ascopore and some areolae sealed.

At stage 5, the secondary orifice and most other openings are closed. Internal calcifing tissues (dashed line), cuticle (heavy line), and other features are Indicated for the individual of stage 3. COLONY BASAL AREA COLONY DISTAL MARGIN

Ep i f rontaI Membra ne CaIca reous Frontal WaI P e r i s t o m e Ascopore Areola Distal WaI

BasaI WaI I

Vest i buIe T e n t a c I e Sheath

LateraI 1 Wa I I

0 .2 5 i_ — i m m , 36

Stages 2 and 3 of Figure 4 are typical of such zooecia. Although a few individuals distal to stage 2 and proximal to stage 3 might be appropriate for study, stages

2 and 3 are generally representative of the limits beyond which zooecia were not evaluated for phenetic comparison.

It should be noted that one or several zooecia may be pres ent between stages 2 and 3 (or between any other two gener alized stages) as suitable intermediates and such individuals were studied.

A diagrammatical frontal view of an Adeonellopsls colony fragment is shown in Figure 5, and ontogenetic regions indicated correspond in a general way to those of Figure 4.

Characteristic frontal structures and relationships are sum marized for each ontogenetic region. "Mature" zooecia pri marily used for study purposes are those at the N-3 level, although not all characters pertain to these zooecia.

The relation between the observed morphologic changes in the frontal wall of Adeonellopsls and its skeletal micro structure and mineralogy have not been investigated. Rucker and Carver (1969) found mixed calcite and aragonite in a

Recent specimen of the closely related genus Adeona. and thus the adeonids may have ontogenetic changes in microstruc ture and composition similar to those described in the asco- phoran Metrarabdotos by Cheetham, Rucker and Carver (1969)*

The Importance of the form and mode of growth of skeletal tissue in general and the attendant systematic impli cations for cheilostomes and all bryozoans is being increasingly 37

FIGURE 5

Diagrammatical representation of an Adeonellopsls colony fragment showing generalized ontogenetic levels (N) and their characteristics. Co 1ony Distal Ma rg I n

• - Frontal wall absent or Incom plete; avicularia lacking; Ck QO ascopore only partly formed. o a C 0 ■ a O o 1 o Frontal wall complete, but thin; a A ascopore complete; some avicu- N-2 A A w larla forming, others complete. Li Li y & a . 0 a a a n d a t o a a Frontal wall moderately thick; o g e avicularia complete; ascopore Ci a prominent; total area and n -3 n areolae distinct; no occlusion d o Q e of frontal openings. t a a I a d d c a a G a a a r a Frontal wall thicker; some A A openings occluded but most u d features distinct; ascopore o Ck I constricted . e n

■ t Frontal wall very thick; most surface features including orifice, ascopore and areolae \t o c c 1uded . -

Co 1ony Basa 1 Area

0 1 m m . 39 reoognized, however (Boardman and Cheetham, 1969). Harraer

(1957) implies that morphological comparisons among the

Ascophora are not valid unless the pattern of frontal wall formation is considered. Skeletal composition and mineralogy is also figuring as a major aspect of cheilostome investiga tions (Rucker, 1969* Schopf and Manhelm, 1968; Schopf and

Allen, 1970). Such studies for Adeonellonsls are the next logical steps in understanding its morphology and evolution.

Gonoecial Characteristics

Gonoecia are obvious and distinctive Individuals.

With their swollen appearance, large size, more numerous ascopore openings and wider oral dimensions, they effectively dominate the zoarlal regions where they occur. As in other adeonids, these individuals, which in living species investi gated incubate larvae, evidently develop from zooecia or as zooecia. Where present, gonoecia occur on both sides of the zoarial laminae but they may be Individually scattered among zooecia or associated with others like them to form gonoecial clumps or clusters.

With regard to the occurrence and placement of suboral and other avicularla, the relationships noted for gonoecia are much like those for zooecia. The ascopore region on gonoecia is quite large, however, and shows numerous, typically stellate pores. This cribriform area may be noticeably con vex upward. Modification and occlusion of such surface features concomitant with frontal wall development is also 40 similar to that reported for zooecia. The distal swelling and peristome 11 capM exhibited by some Adeonellopsls gonoecia is not the same as the more ovicell-like structure of the gonoecia in Metrarabdotos and Schizostomella. The gonoecia of Adeonellopsls more closely resemble ordinary zooecia.

The histograms of Figure 6 are based on data from ten zooecia and ten gonoecia in Sampling Unit 9. These com parisons demonstrate dimorphism in several variates common among the zooecia and gonoecia in many colonies. Although gonoecia are usually identifiable by their general appear ance, more objective criteria for their recognition are in dicated by this information, especially with regard to lz and lo. While gonoecia are conspicuous and frequent, their distribution is not universal in the samples\)ollected for this research. In some species, they have not yet been rec ognized.

Quantitative Characters

Common numerical observations employed in cheilostome studies include those pertaining to zooecial and gonoecial length and width, avicularian size, oral dimensions and counts of various features. Such standard measurements

(Lz, Lg, lz, lg, ho, lo, Lav) were completed for this study on '’mature" individuals as previous defined. Tables II A and II B present summary statistics for these quantitative attributes and show the number of observations in each sam pling unit for each variate. Oral dimensions recorded are 41

FIGURE 6

Histograms showing length (lz), width (lz), oral length (ho), and oral width (lo) values for ten zooecia and ten gonoecia,

Sampling Unit 9. 10 -1 10 n 10 -i 10 -i Lz ho

40 .4550 55 .06 .07 .08 .09 .05 20 m m . m m . m m . m m .

1 0 - i 10 -i Lz ho

-55 .06 .07 .08 .09 .10 .15 .20 m m . m m . mm . m m . 43

TABLE II A. ZOOECIAL VARIATES

For each sampling unit, the column figures for each character are listed in order as follows: mean, standard deviation, coefficient of variation and sample size. Mean and standard deviation values are in millimeters.

Unit Lz lz ho lo Lav

1 0.5060 0.2767 0.0727 0.1013 0.1000 0.0358 0.0126 0.0126 0.0118 0.0148 7.06 7.05 17.38 11.68 14.83 15 15 15 15 15

2 0.3620 0.2090 0.0790 0.0880 0.0729 0.0297 0.0145 0.0134 0.0145 0.0138 8.19 6.93 16.96 16.46 18.90 10 10 10 10 7

3 0.4325 0.2215 0.0725 0.0940 0.1071 0.0446 0.0184 0.0155 0.0152 0.0179 10.31 8.32 21.38 16.12 16.69 20 20 20 20 17

3A 0.3570 0.1900 0.0790 0.0770 0.0640 0.0230 0.0148 0.0095 0.0105 0.0063 6.45 7.81 12.00 13.61 9.86 10 10 10 10 10

4 0.4291 0.2136 0.0773 0.0873 0.0900 0.0372 0.0224 0.0089 0.0134 0.0105 8.69 10.47 11.57 15.36 11.64 11 11 11 11 10

5 0.3977 0.2269 0.0662 0.0777 0.0691 0.0322 0.0160 0.0119 0.0148 0.0094 8.09 7.05 18.00 19.05 13.65 13 13 13 13 11

6 0.4250 0.2133 0.0666 0.0883 0.0617 0.0356 0.0103 0.0081 0.0133 0.0075 8.38 4.83 12.20 15.02 12.13 6 6 6 6 6

7 0.5315 0.2255 0.0690 0.0871 0.0642 0.0652 0.0132 0.0112 0.0158 0.0101 12.27 5.83 16.20 18.11 15.81 20 20 20 20 15 44

TABLE II A. Continued

Unit Lz lz ho lo Lav

8 0.4460 0.2120 0.0655 0.0855 0.0700 0.0391 0.0128 0.0105 0.0105 0.0097 8.77 6.04 16.01 12.27 13.85 20 20 20 20 13

9 0.4785 0.2385 0.0640 0.0805 0.0763 0.0350 0.0223 0.0075 0.0075 0.0121 7.31 9.35 11.69 9.37 15.84 20 20 20 19 19

10 0.4660 0.2400 0.0640 0.0868 0.0774 0.0318 0.0217 0.0082 0.0105 0.0141 6.83 9.06 12.78 12.14 18.18 20 20 20 19 19

11 0.4655 0.2245 0.0605 0.0845 0.0672 0.0579 0.0274 0.0107 0.0094 0.0107 12.45 12.21 17.72 11.16 15.96 20 20 20 20 18

12 0.4725 0.2430 0.0690 0.0785 0.0745 0.0439 0.0175 0.0107 0.0093 0.0075 9.29 7.20 15.47 11.88 10.13 20 20 20 20 20

13 0.4300 0.1887 0.0560 0.0853 0.0620 0.0325 0.0185 0.0140 0.0135 0.0101 7.56 9.78 25.06 15.86 16.29 15 15 15 15 15

14 0.4800 0.2290 0.0670 0.0875 0.0660 0.0441 0.0238 0.0092 0.0091 0.0127 9.19 10.39 13.76 10.34 19.28 20 20 20 20 20

15 0.4790 0.2335 0.0660 0.0880 0.0620 0.0481 0.0305 0.0082 0.0144 0.0105 10.04 13.05 12.40 16.31 16.99 20 20 20 20 20

16 0.4450 0.2060 0.0650 0.0850 0.0745 0.0242 0.8546 0.0114 0.0128 0.0105 5.43 8.53 17.61 15.02 14.08 20 20 20 20 20 45 TABLE II A. Continued

Unit Lz lz ho lo Lav 17 0.4470 0.2320 0.0630 0.0860 0.076 0.0476 0.0147 0.0048 0.0744 0.0117 10.65 6.35 7.61 8.06 15.40 10 10 10 10 10

18 0.4690 0.2220 0.0645 0.0850 0.0647 0.0346 0.0233 0.0123 0.0160 0.0154 7.38 10.50 19.11 18.86 23.79 20 20 20 20 19

19 0.4435 0.2090 0.0570 0.0770 0.0680 0.0342 0.0162 0.0047 0.0108 0.0100 7.72 7.74 8.23 13.99 14.78 20 20 20 20 20

20 0.4260 0.2130 0.0700 0.0900 0.0600 0.0411 0.0189 0.0169 0.0169 0.0151 9.66 8.86 24.25 18.85 25.16 10 10 10 10 8

21 0.4285 0.2215 0.0605 0.0840 0.0670 0.0398 0.0347 0.0114 0.0140 0.0147 9.28 15.65 18.91 12.42 21.93 20 20 20 20 20

22 0.4670 0.2255 0.0630 0.0745 0.0690 0.0435 0.0219 0.0073 0.0105 0.0116 9.32 9.69 11.56 14.08 16.84 20 20 20 20 20

23 0.4565 0.2205 0.0670 0.0830 0.0620 0.0281 0.0219 0.0086 0.0086 0.0061 6.16 9.92 12.84 10.36 9.81 20 20 20 20 20

24 0.4673 0.2313 0.0660 0.0987 0.0587 0.0492 0.0256 0.0184 0.0124 0.0150 10.53 11.06 27.94 12.61 25.61 20 20 20 20 20

25 0.4427 0.2133 0.0753 0.0893 0.0557 0.0438 0.0180 0.0119 0.0096 0.0096 9.90 8.42 15.77 10.74 17.41 20 20 20 20 18 46

TABLE II A. Continued

Unit Lz lz ho lo Lav

26 0.0452 0.2100 0.0660 0.0760 0.0560 0.0335 0.0173 0.0167 0.0089 0.0056 7.40 8.25 25.35 11.77 9.78 5 5 5 5 5

27 0.4773 0.2233 0.0840 0.1020 0.0629 0.0461 0.0360 0.0105 0.0120 0.0114 9.65 16.11 12.54 11.80 18.06 20 20 20 20 19

28 0.4870 0.2250 0.0670 0.0878 0.0700 0.0320 0.0313 0.0149 0.0120 0.0109 6.57 13.93 22.28 13.67 15.65 10 10 10 9 6

29 0.4553 0.2167 0.0740 0.0947 0.0613 0.0320 0.0154 0.0124 0.0112 0.0083 7.03 7.12 16.77 11.85 13.55 15 15 15 15 15

30 0.4360 0.1990 0.0910 0.1050 0.0890 0.0362 0.0212 0.0118 0.0084 0.0071 8.30 10.66 13.00 7.96 7.98 10 10 10 10 10

31 0.4491 0.2291 0.1091 0.1236 0.0820 0.0345 0.0182 0.0130 0.0126 0.0089 7.68 7.93 11.94 10.23 10.90 11 11 11 11 10

32 0.4320 0.1960 0.0690 0.0870 0.0620 0.0275 0.0134 0.0095 0.0122 0.0078 6.34 6.84 13.74 14.07 12.48 10 10 10 10 10 47

TABLE II B. GONOECIAL VARIATES

Statistical measures and data sequence are the same as shown in Table II A.

Unit Lg lg ho lo Lav

1 0.4750 0.2800 0.0600 0.1000 0.0766 0.0331 0.0360 0.0141 0.0141 0.0071 6.96 12.85 23.50 14.10 9.23 5 5 5 5 5

0.3760 0.2700 0.0650 0.1260 0.0833 0.0276 0.0170 0.0085 0.0135 0.0200 7.33 6.29 13.05 10.71 24.00 10 10 10 10 9

0.4960 0.2800 0.0540 0.1280 0.0725 0.0299 0.0249 0.0135 0.0140 0.0103 6.02 8.91 24.98 10.91 14.27 10 10 10 10 3

0.4400 0.2900 0.0680 0.1280 0 . 0 7 H 0.0333 0.0194 0.0140 0.0162 0.0117 7.56 6.70 20.53 12.64 16.40 10 10 10 10 9 48

TABLE II B. Continued

Unit Lg lg ho lo Lav

9 0.4680 0.2990 0.0690 0.1260 0.0760 0.0270 0.0228 0.0087 0.0143 0.0157 5.77 7.63 12.63 11.33 20.72 10 10 10 10 10

10 0.4610 0.2830 0.0630 0.1200 0.0680 0.0448 0.0189 0.0095 0.0066 0.0092 9.73 6.67 15.06 5.53 13.48 10 10 10 10 10

11 0.4670 0.2710 0.0580 0.1200 0.0663 0.0549 0.0247 0.0155 0.0163 0.0092 11.77 9.11 26.70 13.59 13.82 10 10 10 10 8

12 0.4700 0.2780 0.0570 0.1230 0.0660 0.0427 0.0155 0.0095 0.0106 0.0107 9.08 5.57 16.64 8.60 16.24 10 10 10 10 10

13 0.4080 0.2260 0.0730 0.1340 0.0520 0.0368 0.0189 0.0221 0.0250 0.0113 9.01 8.39 30.32 18.67 21.76 10 10 10 10 10

14 0.4740 0.2880 0.0580 0.1220 0.0760 0.0366 0.0266 0.0139 0.0092 0.0150 7.71 9.22 24.07 7.51 19.78 10 10 10 10 10

15 0.4640 0.2790 0.0570 0.1230 0.0790 0.0347 0.0166 0.0067 0.0116 0.0166 7.48 5.95 11.77 9.41 21.03 10 10 10 10 10

16 0.4460 0.2790 0.0610 0.1250 0.0629 0.0331 0.0238 0.0191 0.0171 0.0125 7.41 8.52 31.31 13.72 19.92 10 10 10 10 8

17 0.4470 0.2840 0.0540 0.1250 0.0666 0.0442 0.0126 0.0069 0.0085 0.0121 9.89 4.45 12.82 6.78 18.14 10 10 10 10 6 49

TABLE II B. Continued

Unit Lg 16 ho lo Lav

18 0.4600 0.2630 0.0600 0.1240 0 0625 0.0326 0.0200 0.0124 0.0096 0 0138 7.08 7.61 20.74 7.7 8 22 17 10 10 10 10 8

19 0.4650 0.2690 0.0520 0.1220 0 0637 0.0502 0.0152 0.0147 0.0092 0 0106 10.79 5.66 28.33 7.51 16 61 10 10 10 10 8

20 0.4200 0.2586 0.0586 0.1443 0 0600 0.0258 0.0168 0.0037 0.0139 0 0071 6.14 6.48 6.38 9.68 11 78 7 7 7 7 5

21 0.4290 0.2680 0.0640 0.1200 0 0637 0.0321 0.0187 0.0117 0.0081 0 0130 7.49 6.99 18.28 6.77 20 41 10 10 10 10 8

22 0.4680 0.2810 0.0478 0.1270 0 0867 0.0436 0.0179 0.0097 0.0082 0 0200 9.33 6.37 20.28 6.44 23 07 10 10 10 10 9

23 0.4740 0.2820 0.0580 0.1230 0 0678 0.0403 0.0181 0.0041 0.0106 0 0109 8.51 6.42 7.11 8.60 16 09 10 10 10 10 9

24 0.4770 0.2830 0.0760 0.1570 0 0744 0.0368 0.0267 0.0201 0.0309 0 0133 7.72 9.43 26.45 19.69 17 88 10 10 10 10 9

25 0.4233 0.2867 0.0833 0.1250 0 0700 0.0163 0.0163 0.0103 0.0084 0 0115 3.85 5.69 12.36 6.69 16 47 6 6 6 6 5

26 Not; Observed

27 0.4720 0.2610 0.0690 0.1550 0 0750 0.0235 0.0159 0.0208 0.0212 0 0169 4.97 6.11 30.12 13.68 22 51 10 10 10 10 8 50

TABLE II B. Continued

Unit Lg lg ho lo Lav

28 0.4790 0.2480 0.0670 0.1244 0.0622 0.0242 0.0235 0.0116 0.0159 0.0083 5.06 9.46 17.28 12.76 13.35 10 10 9 9 9

29 0.4610 0.2740 0.0630 0.1300 0.0800 0.0218 0.0190 0.0187 0.0115 0.0163 4.73 6.92 29.95 8.87 20.39 10 10 10 10 7

32 0.3980 0.2140 0.0580 0.1080 0.0560 0.0130 0.0089 0.0083 0.0084 0.0055 3.27 4.18 14.41 7.74 9.77 5 5 5 5 5 51 those of the secondary orifice as the primary one is seldom visible in frontal view and few interiors were available for Interpretation in many sampling units.

The data indicate that the withln-sample quantitative variation, while somewhat high, corresponds to that exhibited by many cheilostomes (Cheetham, 1966; 1968). Coefficients of variation (V) are typically under 10 for length and width measurements, but normally between 10 and 20 for oral variates and avicularian length. With one exception, the few

V values over 25 apply to oral length. Some of the high values for ho may be due to erosion around the proximal mar gin of the secondary orifice in certain specimens. The histo grams of Figures 7 and 8 summarize the data from the above tables in terms of classes of V.

As earlier comments Indicate, Intracolony variation is significant with regard to ontogeny. However, the gen eral absence of young zooecia in the study samples and the obscurity of zooecial features and boundaries on old zooecia limit the number of good measurements possible on such in dividuals .

As size factors may have genetic implication, sample unit means for length were plotted against those for width to obtain three general size groupings for zooecia (Figure 9) and two for gonoecia (Figure 10). Similarly, mean zooecial oral dimensions were used to establish three general size groups with respect to this characteristic (Figure 11). Mean gonoecial oral dimensions were considered independently, FIGURE 7

Histogram summaries of coefficient of variation data from Table II A (Zooecia). Units Units Units Lz I o 30 30 30

20 20 - 20

10 10

0 0 0 10 0 15 20 10 15 20 V V

Units Units ho Lav

20 20

10 - 10 -

0 5 15 30 0 5 1 0 20 25

ZOOECi A FIGURE 8

Histogram summaries of coefficient of variation data from Table II B (Gonoecia). Units Units Units Lz 30 - 30 - 30

20 -

10 -

10 15 20 10 15 20 10 15 20 V V V

Units Units ho Lav 30 30 -

0 0 15 20 25 10 15 20 25 V GONOECI A FIGURE 9

Scatter polygons for mean zooecial dimensions. . m m Zooecial Length (Lz) .40 .60 .50 30 .00

r J _____ ZOOECI ZOOECI A ZOOECIA ZOOECIA MODERATE 1 .0 .30 .20 .10 SMALL LARGE I _____ oe a Wdh (lz) Width ialZooec

I ----- 1 ----- 1 ----- apig nt J , Units 7 Sampling 1 3,4,6, Units Sampling apig nt 2,3A,5 Units Sampling ----- L .40 mm 8-32 FIGURE 10

Scatter polygons for mean gonoecial dimensions. mm. .60 r

+--C Sampling Units 1,7,8-29 _i GONOECIA LARGE to o © GONOECIA o Sampling Units 5,13,32 c SMALL o o

.10 20 .30 Gonoec i a I Width (Ig) 60

FIGURE 11

Scatter polygons for mean zooecial oral dimensions. nm. Ora I Length (ho ) .05 .06 .07 .10 .11 08 .06 RL SIZE ORAL SMALL RL SIZE ORAL MODERATE .07

.08 r Wdh Io) ( Ora Width I .09 .10 RL SIZE ORAL AG , LARGE apig nt ]233A,4,25,29 A ],2,3,3 Units Sampling apig nt 5-24,26,28,32 Units Sampling .11

.12 apig nt 27,30,3J Units Sampling ■13

m m . however, to establish divisions. Gonoecial oral height or

length is considered here as short, moderate or long if the

sample mean value for this variate is less than 0.055 mm.,

between 0.055 mm. and 0.075 mm. or greater than 0.075 mm.,

respectively. Gonoecial oral width is considered narrow if

mean values are less than 0.12 mm., moderate if values are

between 0.12 mm. and 0.14 mm. and broad if the values exceed

0.14 mm. For both zooecia and gonoecia, suboral avlcularian

length is considered short, moderate or long if sampling unit

means are less than 0.06 mm., between 0.06 mm. and 0.08 mm. or greater than 0.08 mm., respectively. PHENETIC COMPARISON

Quantitative and qualitative attributes of the

Adeonellopsls Gulf samples were used to establish suitable

morphologic data for subsequent numerical investigation.

The method used clusters or groups together sampling units

on the basis of degrees of morphologic resemblance. The

morphologic clusters so derived can be interpreted taxo-

nomically by consideration of their stratigraphic distri butions as done by Cheetham (1968) in a systematic study of

the bryozoan Metrarabdotos. Cluster analysis was also used

by Rucker (1967) in a paleoecologlcal evaluation of bryozoans

in Venezuelan shelf sediments.

In order to evaluate the fossil specimens in a man ner consistent with the concepts and factors pertaining to biological species, phenetic comparison was limited to those

characters inferred to reflect genetic differences. These

characters were then used as a basis for grouping the organ

isms into morphologic clusters. As stated by Boardman,

Cheetham and Cook (1969), the recognition of such genetically

controlled variation in Bryozoa is partially solved by the nature of their colonial growth. As normally all members of

a bryozoan colony can be considered as possessing a common

genotype, phenetio relationships between genetic equals in

a single colony and between comparable individuals among 64 colonies can be assessed when such previously discussed sources of extragenetlc variation as ontogeny, astogeny, polymorphism, and microhabitat are recognized.

The quantitative characters relating to zooecial, oral, and avicularlan size established on the basis of re lationships previously Indicated in Figures 9, 10, and 11 as discussed earlier were each coded in 2 to 4 numerical states. Qualitative characters, established through inter pretation of zooecial and gonoeclal morphology discussed earlier were also expressed in the form of a simple numeri cal code. A total of 35 zooecial and 9 gonoecial characters were thus expressed numerically.

Table III shows each of these 44 morphologic charac ters and explains the numerical code for their states. About half of the characters have two states and most of the remain ing ones are expressed with three states. No special char acter weighting procedures were used other than that general morphologic difference is Indicated by the arithmetic dif ference between states for any particular character. State sequences were assigned completely morphologically rather than stratigraphically in order to place all of the distribu tional interpretation at the end of the comparison procedure.

Where possible, 20 zooecia and 10 gonoecia in each of the

33 sampling units were evaluated with respect to each charac ter. Restrictions related to sample size and condition re duced the desired number of observations in certain cases as

Table II indicates. 65

TABLE III. ADEONELLOPSIS MORPHOLOGIC CHARACTERS

Character States

1. Zooecial size 0=small l=moderate; 2=large.

2. Oral size 0=small; l=moderate; 2=large.

3. Length suboral avicularlum 0=short; l=moderate 2=long.

4. Orientation suboral O=predominantly distal; avicularlum l=varlable; 2=predominantly lateral.

5. Position suboral 0=ln peristome area; avicularlum l=removed from area.

6. Shape suboral avicularlum O=moderately rounded; l=pointed.

7. Curvature suboral 0=not curved; 1=curved avicularlum upward.

8. Lateral wall contaot- 0=none; l=contact. suboral avicularlum

9. Suboral avicularlum 0=absent or indistinct; bridge l=promlnent

10. Distal avicularlum 0=absent; l=present on fewer than half zooecia; 2=present on more than half zooecia.

11. Lateral avicularlum 0=absent;' l=present on fewer than half zooecia; 2=present on more than half zooecia.

12. Proximal avicularlum 0=absent; l=present on fewer than half zooecia; 2=present on more than half zooecia.

13. Projecting proximal 0=no; l=distinct. avicularlum

14. Adventitious avloularia 0=absent; l=present. 66

TABLE III. Continued

Character States

15. Adventitious avicularia- 0=absent; l=present. old zooecia

16. Multiple avicularia on 0=no; l=yes. peristome

17. Size ascopore area 0=small; l=moderate; 2=large.

18. Number of ascopore pores 0=usually 2-5; l=usually more than 3.

19. Size ascopore pores 0= s mal 1; 1= large.

20. Shape ascopore pores 0=polygonal rounded; 2=stellate; 3=incompletely stellate.

21. Ascopore position with 0=close; l=removed. respect to peristome

22. Peristome hood 0=absent; l=present reduced; 2=present elevated.

23. Peristome edge 0=normal; l=thin; 2= thick.

24. Oral "denticle” 0=absent or indistinct; lrridentifiable.

25. Cribriform area 0=shallow; l=deep.

26. "Total area" development 0=reduced; l=marked.

27. "Total area" shape 0=wlde elliptical; l=elongate; 2=tapered.

28. "Total area" olosed- O=predominantly closed; old zooecia l=aperture or some opening remains.

29. Bulbous outgrowths 0=absent; l=present zooecial rim

30. Distinctive marginal 0=no; l=yes. zooecia in colony 67

TABLE III. Continued

Character States

31. Zoarlal diversity 0=absent; l=some apparent.

32. Zooecia separated- 0=no; l=ridge distinct. thln ridge

33. Areolar shape 0=rounded; l=elongate.

34. Areolar development 0=reduced; l=marked.

35. Frontal closure 0=weak; Inconspicuous.

36. Gonoeclal size 0=gonoeoia absent; l=small; 2=large.

37. Gonoeclal oral width 0=gonoeoia absent; l=narrow; 2=moderate; 3=broad.

38. Gonoeclal oral height 0=gonoecia absent; l=short; 2=moderate; 3=long.

39. Length gonoeclal 0=gonoecla absent; suboral avicularlum l=short; 2=moderate; 3=long.

40. Orientation gonoeclal 0=gonoecla absent; suboral avicularlum l=predominantly lateral; 2=variable distal- lateral

41. Distal avicularlum Ongonoecia absent; gonoecia l=present on fewer than half specimens; 2=present more than half.

42. Proximal avicularlum Ongonoecia absent; gonoecia l=avicularium absent; 2=present on fewer than half of specimens; 3=present on more than half of specimens.

43. Convex cribriform 0=gonoeola absent; l=no; area gonoecia 2=yes.

44. Gonoecia colony position 0=gonoecia absent; Lrscattered; 2=clumped. 68

With regard to gonoeclal characters, the character state "gonoeola absent" and a code digit was employed instead of an "X" or no comparison type of observation in order to give some weight to this particular phenomenon and have it

Included in data manipulation. This was done because absence of gonoecia was considered to be a significant morphologic condition rather than a sampling artifact.

This information was summarized in an initial data matrix (Appendix) which displays a discrete numerical code entry for each character for each sampling unit. The matrix was analyzed in a series of steps to determine resemblances between entitles or cases (sampling units as used here) based on a number of variables or characteristics (characters as used here). This type of matrix examination, which con siders the association of pairs of OTU*s (matrix columns) over all characters (matrix rows) is called Q-mode analysis in contrast to R-mode analysis which considers correlations among the various characters (Cattell, 1952).

The initial matrix was first standardized so that each character (row) has a mean of zero and a variance of one. This procedure overcomes some of the problems asso ciated with analysis involving arbitrarily coded data and varying numbers of states for different characters in that it permits the postulation that the variates for each OTU are from "populations" of characters having a common mean

(Sokal and Sneath, 1963). In other words, all characters used have equal weight. As measures of overall morphologic 69 similarity or difference in the 44 characters, Pearson product-moment correlation coefficients (r) and Sokal taxonomio distance coefficients (d) between each pair of sampling units were computed from the standardized matrix scores.

These coefficients were then organized to form separate correlation and distance matrices which were used as bases for clustering similar sampling units.

Two cluster diagrams or dendrograms showing related sampling units were prepared from each similarity-dlfference matrix, one by the weighted pair-group method (WPGM) and one by the unweighted pair-group method (UPGM). The pair group methods permit only the two most highly correlated stems to

Join at each clustering cycle, and the similarities and differences between the clustered OTU*s and those remaining are recomputed as arithmetic averages. The UPGM option com putes these averages from the original similarity or differ ence matrix at every clustering cycle, but the WPGM option considers each Joiner the equal of all previous members of a cluster. These procedures are standard in numerical taxonomy (Sokal and Sneath, 1963), and were performed on a digital computer.

The four dendrograms generated are shown on Figures

12, 13, 14, and 15 and clusters are Indicated by letters.

Phenon lines are drawn on these diagrams merely to develop sampling unit clusters of equal rank, not to indicate any particular taxonomio level. It should be noted that for clusters based on both r and d, cluster composition and FIGURE 12

Dendrogram from clustering of the correlation coefficient matrix (WPGM), Seven clusters A-G are indicated at the ,12 level. I I

*» >- to cn m oo co — r T r T _T_ "T" T T T

1 3 2 31 G ■ c 30 3A 4 - 5 8 9 11 13 rc 14 17 15 18 22. 10' 21 E 29. 28 27 D 12. 6 ' C 7 . 32' 19 20 23 B 24 25 26. i . ] A

I 1 I i I I t » t I » I FIGURE 13

Dendrogram from clustering of the correlation coefficient matrix (UPGM). Eight clusters A-H are Indicated at the .18 level. CD U _ L U Q O m < — 1 i 1 ii<' n-■ ■■—-^r i r " ■!«■' 1 n |

h n n n n n « iAooaNN*4HiNf4NNNN h h h n h n n n n n (*, to r<-

0.8

0.7

0.6

0.5 r

0.3

0.2

0.0

- 0.1

- 0.2 FIGURE 14

Dendrogram from clustering of the taxonomic distance matrix (WPGM). Five clusters A-E are Indicated at the 1.3 level. »*z zz O'l

8 1

9‘ I

r i

Z ' l P

o x

• 8'0

9'0 P'O - Z ’O

- 0*0 H w « w w WN NNlOOOaJOlUIMNMNlHKH L II II I r* ° ** _ f ° 00 I N| Wl (fl O a> w M w ^Meois>MO(oi-*e

> CD O O m FIGURE 15

Dendrogram from clustering of the taxonomic distance matrix (UPGM). Five clusters A-E are indicated at the 1.4 level. CL

M Is* M e ■ Is* 00 e> Is* o

10 21 19 20 23 32 18 22 24 11 13 14 17 15 12 16 29 25 6 7 5 8 9 27 26 2 8J 2 3A D 30 31. 4 3 ] B l J A 78 order is somewhat different depending on whether the WPGM or UPGM method was employed. Even though clustering at low similarity levels is different for both dendrograms based on r, the members of these two clusters are, with few excep tions, identical. Some switching about of OTU's is perhaps related to the relatively few characters employed, although the member of characters used is greater than the minimum of

40 suggested for such operations. Also, some OTU's, such as Unit 26, have a large number of "no comparison" matrix entries which affects their position.

Figure 16 also indicates 7 phenetic clusters de veloped approximately at the 0.2 level of similarity. Al though the correlation coefficient has been used as a basis for taxonomic interpretations, some criticism has been made concerning the use of r in Q-mode studies and related analyses

(Johnson, 1962; Sokal and Sneath, 1963; Eades, 1965; and

Park, 1968). While several of the sampling unit groups of

Figure 16 are broad and inclusive ones, they are nevertheless logical and natural clusters with respect to gross stratigraphy and morphology which suggests that use of the correlation statistic is not entirely inappropriate. The results of the recent study of Metrarabdotos by Cheetham (1968) also tend to support this latter view.

The dendrogram of Figure 14 is based on taxonomic distance (d) as an index of (reverse) similarity. Five phenetic clusters at the 1.3 level are shown and these groups are again natural and logical ones. Because they are more FIGURE 16

Dendrogram (as in Figure 12) based on correlation

coefficient matrix (WPGM). Seven phenetic clusters

A-G are developed at approximately the 0.2 level. CD LU o CO i 11 11 r— — — i o ^ m « N IA CO N e # < f* n n a o n « m h n n n n n « i d w n H H ^ ^4 H N

N N N ^ I O N m n NNNN 26 J 1.0 r-

0.9

0.8

0.7

0.6

0.5 r 0.4

0.3 0.2

0.1

0.0

— 0.1

— 0.2 consistent with detailed stratigraphy, the phenetic units of Figure 14 developed from the taxonomic distance matrix were selected to serve as a basis for taxonomic interpreta tion. Conformity to stratigraphic sequence is considered here as the ultimate criterion of goodness of fit of the dendrogram. PHYLOGENY AND TAXONOMY

General Relationships

Phenetio associations based on similarities and differences among particular organisms as Judged by their morphologic characters can be considered in two primary ways. As indicated by Sokal and Sneath (1963), groups can be formed by rigid, logical divisions so that the possession of a unique set of features is both sufficient and necessary for membership in the group. As the defining set of charac teristics in such phenetic groups is unique, they are termed monothetic. A polythetic arrangement places together those organisms that have the largest number of shared features with no one feature or character state essential to member ship in or exclusion from a group. With respect to a par ticular set of features, such polythetic groups possess a large number of the features in the set, and, while each feature of the set is ideally possessed by large numbers of individuals, no single feature is necessarily possessed by each member of the group. Both Simpson (1961) and Sokal and Sneath (1963) discuss more extensively the history and philosophical rationale of these two approaches.

It is probably not possible to find any single diag nostic character for a natural taxonomic group of any rank. 83

Such natural taxa (as opposed to strictly artificial groups) according to Gilmour (1937) are entitles grouped together in such a way that members of the group have many attributes

In common. Sokal and Sneath (1963) maintain that the elu sive property of “naturalness" with respect to groups of organisms is the degree to which this principle obtains. Early support for the view is found in the work of Adanson (1763) who developed a concept of "affinity" measured by considering all characters and believed that taxa are separable from each other by means of correlated features rather than a priori assumptions of the significance of certain characters, espe cially in incompletely known groups. Systematists studying fossil materials realize however that similar features among groups may be homologous or homoplastic. Consequently, tem poral and spatial variations in morphologic characters and phylogenetic patterns of groups exhibiting them must be con sidered when such features are evaluated for taxonomic pur poses.

It has also been implied that natural classification systems have a high content of information, serve a variety of purposes, permit objective testing and allow appropriate phylogenetic inferences (Sokal and Sneath, 1963). Polythetic groups inherently provide a natural basis, both theoretical and practical, for such groupings. As a rule, monothetlc approaches do not yield natural taxa in the sense considered here. Good general case examples concerning character inter pretation and distribution and monothetlc and polythetic 84 approaohes In bryozoan taxonomy are presented by Boardman,

Cheetham and Cook (1969).

These latter workers also Indicate low correlations among genetically controlled characters in Bryozoa from population to population, citing the possible lack of severe modification by selection on the pattern of mutational ran domness which reflects all kinds of bryozoan character combi nations. As a result, they state that the search for combi nations of diagnostic characters as a basis for taxonomic grouping in the phylum has not been successful. Polythetic groups, organized by calculating similarities among popula tions based on many attributes, are thus especially suitable for odering and interpreting bryozoan species and their com ponent populations. The usefulness of such an approach for higher level taxa in Bryozoa has also been suggested (Board man, Cheetham and Cook, 1969).

Phylogenetic Relationships and Taxonomy

Population systems evolve by progressive changes within them and by division and separation into new systems, the fundamental unit of evolution being the species (Simpson,

1961). While this category is naturally defined only on the basis of evolutionary relationships among populations and not on morphology, morphologic characteristics provide evi dence revealing the dynamic character of these relationships.

Evolutionary taxonomy thus involves phylogeny which requires inferences about propinquity of desoent. Sokal and Sneath 85

(1963) strongly criticize the employment of phylogenetic

Inference In taxonomic work. Although their arguments are principally directed toward neontological systematlcs, they feel that even paleontological schemes cannot effectively discern or incorporate such patterns. This current study, however, considers that such Inference, properly based, is the most appropriate way to realize the order inherent In evolving natural systems and to develop a suitable hierarchi cal framework for analysis of it.

Boardman, Cheetham and Cook (1969) state that a phenetic arrangement genetically based and polythetically derived is not necessarily phylogenetic. As they report, such an evolutionary classification requires inference of genetic continuity and compatibility based on both phenetic similarity and time-space proximity. The clusters A-E of

Figure 14 are polythetic ones based on phenetic characters inferred to be genetically controlled. Such phenetic groups may be interpreted taxonomically when considered with their distributional data which serves as a basis for inference concerning genetic compatibility and continuity. Category determination is a function of the levels of similarity or distance at which the colony groups cluster and of their spatial and temporal positions.

The "contour map" of Figure 17 is based on the rela tionships indicated in Figure 14. Major clusters formed on the basis of such "contours" correspond to the major phenetic groups A-E of Figure 14. Convergence between sampling units 8 6

FIGURE 17

General "contour map" based on the dendrogram of Figure 14.

"Contour lines" represent levels of joining or clustering of sampling units. Individual numbered units are positioned stratigraphically. Several patterns of convergence, such as that between units 2 and 26, are evident. Heavy lines en close the five major clusters (lettered) of Figure 14. Two subclusters, El and E2, separated by a dashed line, are also suggested on the basis of phenetics and geologic position.

Units 2, 16 and 26 are phonetically out of place with respect to their inferred phylogenetic positions (arrows). Byram Marl

GIendon Fm. HH dHHH Marianna Ls. GEES on

Red Bluff Clay

(Coope r Ma rI ) Shubuta Clay

Pachuta Marl

Moodys Marl Gosport Sand

Lisbon F m . 0

Ba sh i Marl 8 8

2 and 26 is quite apparent as is a similar relationship be

tween unit 16 and units 24 and 29. While four subdueters

are apparent within cluster E at a high level of similarity,

two, more inclusive, subclusters are suggested by stratigraphic

position and morphologic difference. These two subclusters

are more evident when the effects of convergence are elim

inated. The two subclusters, El and E2 of Figure 17, include

sampling units from the Fachuta to Marianna formations and

Glendon to Byram formations, respectively.

These major and minor clusters serve as a basis for

phylogenetic Inference. Figure 18 shows these groups in

time-space position together with the phenetic relationships

of the included individual populations (sampling units).

Phylogenetic relationships are also Indicated, and colony

groups are designated as species and subspecies. The popu

lation clusters phonetically similar at intermediate levels

are here interpreted as species (designated I-V). Two chrono

logic-geographic subspecies are also indicated for species IV.

Although the colonies of sampling unit 5 from the Cooper Marl

of central Georgia are generally similar to the associated

populations of eastern Mississippi and western Alabama, they

are considered here as a geographic subspecies on the basis

of sufficiently distinct morphologic characteristics. While

speoies status is suggested for cluster C of Figure 17 (unit

4) no such determination is made here because available speci

mens are few and stratigraphic control is weak. Additional

information will be required for placement of these colonies. 89

FIGURE 18

Inferred phylogenetic relationships of Adeonellopsls colony groups designated as species and subspecies. Species boun daries are Indicated with a solid line and subspecies boun daries with a dashed line. The one dimensional phenetic difference axis distorts actual phenetic relationships. h_. qa I eata

24 25

A_. cyclops eye lops

\ BS A . eye lops X

III A_. qu i senb e r ryae

ii / ^ T N

t r a n s v e r s a I

h_. mag n i porosa

P H E N E T 1C DIFFERENCE 91

The method used for these determinations estab lishes that phenetio clusters are present and bases phylo genetic Interpretations on them before names are applied.

Phenetic intergradation at any one time or through a time sequence characterizes species and lower level taxa (A. cvclops. for example), but the boundaries between coeval species are usually non-arbltrary in contrast to that between species forming a temporal lineage (Boardman, Cheetham, and

Cook, 1969). This latter relationship is exemplified by A. qulsenberrvae and A. transverse.

All the populations shown in Figure 18 may not be simply related phylogenetically. A. qulsenberrvae appears much more like some European Eocene-Oligocene forms such as

A. punctata and A. porlna. than does A. cvclops and younger

American stocks. A. punctata from the Eocene of France and

Poland especially resembles A. qulsenberrvae although the former has a single zooeclal ascopore and well developed gonoecia are present. Similarly, the small rhombic zooecia, compound ascopore, and weakly differentiated gonoecia of

A. selsevensls from the British Eocene may suggest some relationship with the American A. transversa stock. Consid ering these faotors, the possibility of immigrants from

European stocks starting some Gulf populations should not be discounted. Although no European populations were in cluded in the phenetic clustering here, such a step would be a logical extension of this study in order to establish a basis for more complete phyletic inference of these Tertiary species. 92

High phenetic similarity in the late Eocene and

Oligocene dusters of this nexus Indicates less diversifi

cation and evolutionary change during this time than that

suggested by the earlier Eooene groups. Such similarity

is also indicative of extensive overlap in many morphologic

characters among the Adeonellopsls populations, as discussed

earlier, and points out the unsuitability of a monothetic

evaluation for this complex which would develop artificial

form taxa inconsistent with phylogenetic inference. Thus

OTU's or sampling units 2 and 26, from the Lisbon and Glendon

formations respectively, might be considered a single taxon on the basis of a cluster diagram alone (Figures 14 and 17), but time-space positions of these colonies and interpretation of morphology suggest otherwise.

Late Eocene and Oligocene forms in this American com plex exhibit distinct gonoecia, typically with numerous ascopores, but such individuals are apparently absent or only weakly differentiated in the earlier Eocene populations.

The ascopore area on zooecia of A. transversa. A. cvclops and

A. galeata is smaller and contains fewer pores than A. qulsen berrvae and A. magnlporosa. although A. qulsenberrvae and younger species do have stellate ascopores. Similarly, the suboral avicularium is not as long in younger groups as it is in A. magnlporosa and A. qulsenberrvae and the structure has shifted from an extraoral position to one along the proxi mal margin of the peristome. Also, the older populations do not possess a distinct supraoral frontal convexity or peristome hood characteristic of later species such as

A. cvclops and A. galeata. SUMMARY AND CONCLUSIONS

An examination of Adeonellopsls in the Paleogene strata of the central Gulf Coast identified the major sources of colony and population variation in this chellostome com plex that previously were incompletely evaluated and estab lished species groupings more consistent with biospecles concepts. These determinations were based on a biometric study of numerous morphologic characteristics considered to be genetically based. High phenetic similarity among some

Eocene-Ollgocene populations and extensive overlap in many morphologic features throughout the entire complex invali dates the morphospecies approach used earlier in a study of these ascophorans and precludes any general monothetic eval uation.

The several sources of intracolony variation were considered in order to understand and eliminate from analy sis differences due to ontogeny, astogeny, polymorphism, and microenvironment. Ontogenetic changes are major ones in these colonies and induce variation of such magnitude that careful comparison of appropriate individuals between colonies is necessary. This study differs from the 1920 work of Canu and Bassler by taking such variation, especially frontal wall relationships, into consideration. Remaining phenetic differences were assumed to be of genetic origin 95 and these features were assessed on many individuals in many samples.

A biometric evaluation designed to group similar samples on the basis of these relationships was made using standard procedures in numerical taxonomy. Phonetically similar clusters as derived were placed in a time-space framework to make phylogenetic inferences and taxonomic in terpretations. The classification scheme developed here is phyletic in that phylogenetic interpretations were made for the phenetic groups before names were applied. Thus the methods employed for this study were essentially free of a priori reasoning.

Five species were delimited by these methods and identified with name-bearing specimens— A. magnlporosa.

A. transversa. A. qulsenberrvae. A. cvclops and A. galeata.

One new subspecies is recognized in the upper Eocene-

Oligocene complex. Although no new species are named, one earlier species, A. grandls. was determined to be synonymous with A. cvclops. Lectotypes were also chosen from original syntype suites.

Despite some limitations of cluster analysis, the study techniques and interpretations were considered to be as objective in character as possible as well as polythetic, leading to a more adequate definition and description of paleontological biospecies in this adeonid complex. These techniques revealed relationships often hidden in large data arrays, such as employed here with numerous observations 96 on many variables. Such relationships brought out the sim ilarities among what had been considered distinct species of Adeonellopsls thus showing the undesirability and im- practicality of a morphospecies or monothetlc approach.

The high degree of similarity among colonies of

Adeonellopsls and the associated lack of speciation during late Eocene and Oligocene time also suggest stable environ mental conditions throughout this interval. No analysis of associated faunas and sediments was completed however, but it should be noted that in many samples Adeonellopsls is accompanied by abundant specimens of another erect cheilostome Metrarabdotos. Observation of an Adeonellopsls speci men from the Miocene of northwestern Florida indicates that major features of the Oligocene populations continued to be maintained in eastern Miocene populations as suitable marine conditions became more restricted in the west at this time. SYSTEMATIC DESCRIPTIONS

Order CHEILOSTOMATA Busk, 1852

Suborder ASCOPHORA Levinsen, 1909

Family ADEONIDAE Hincks, 1884

Genus ADEONELLOPSIS MacGillivray, 1886

ADEONELLOPSIS MAGNIPOROSA

Canu and Bassler, 1920

Plate I, Figures 1-4

Plate II, Figures 1-4

Adeonellopsls magnlporosa Canu and Bassler, 1920, p. 565, pi. 8, figs. 14-20.

Diagnosis. Zooecla large; ascopore area large, containing typically 3-7 large, distinct, rounded ascopores, somewhat polygonal in outline; suboral avicularlum long, sub-triangular, distally directed, subjacent to secondary orifice, not usually reaching total area ridge; other avicularia absent except on old zooecla; peristome without hood; gonoecia little distinct from zooecla.

Occurrence. Lower Eooene (Wilcox), Bashi Marl

Member, Hatchitigbee Formation, Alabama.

Material studied. Leototype (here designated)

USNM 63830 (Canu and Bassler, 1920, pi. 8, fig. 20), Paralec totypes USNM specimens (1920, pi. 8, figs. 14-18), 14 speci mens, Bashi Marl, Alabama (Sampling Unit 1). 98

Description. Zoarlum erect, frond-like, bilaminate; laminae thickened, compressed, of moderate width; zooecla occur in eight or more longitudinal rows on either side with number of rows increasing distally; zooecla of adjacent rows alternating in position.

Zooecla large, Irregularly rectangular to claviform, elongate, well separated by furrow and marked total area rim.

Marginal zooecla little distinct from central ones, although ascopore area may not be noticeably depressed.

Frontal wall moderately thick, becoming very thick and more convex with age; upward growth early restricted to zooecial periphery elevates frontal wall above an extensive, elongate, deep oral-ascopore region, the entrance to which is later constricted by medial calcification to a smaller, circular opening and finally sealed. Frontal surface of marked relief; total area elliptical and well-developed; defining rim thick, prominent, and much elevated. Areolae marginal, small, indistinct, elongate and completely en circling zooecla.

Orifice semicircular to sub-elliptical; proximal mar gin smooth and straight, dimensions moderate; secondary ori fice similar, often more elliptical; peristome moderately thick, short, without shallow or deep structures or distal hood.

Suboral avlcularium long, sub-triangular, prominent, directed distally to dlstolaterally but seldom contacting total area rim; removed from secondary orifice but positioned 99 subjacent to It on prominent suboral bar. Distal, lateral and proximal avlcularla normally lacking; occasionally a rounded avlcularium at base of older zooecla.

Ascopore area large, elongate, distinct, little taper ing proxlmally and depressed below .frontal surface, set far from secondary orifice. Typically 3-7 large, distinct, rounded-polygonal, non-stellate, we11-separated ascopores present.

Gonoecia slightly larger than zooecla, infrequent, typical along but not restricted to colony margins, wide, little swollen; suboral avlcularium more lateral in orienta tion; secondary orifice slightly wider.

Remarks. Canu and Bassler (1920) described stellate ascopores for this species but no such pores were observed

In this study. They are distinct and large structures, however, and serve to distinguish this particular taxon from other American forms. The zooecla are also large and may often exceed 0.50 mm. in length. They are encircled by small areolae. Gonoecia were also not recognized by Canu and Bassler. They are little distinct from zooecla, typi cally marginal in position, and exhibit a flatter, more elongate cribriform area. The suboral avlcularium is elongated and triangular or sub-triangular on both young and old zooecla, although Canu and Bassler considered this state typical of only older individuals. ADEONELLOPSIS TRANSVERSA

Canu and Bassler, 1920

Plate III, Figures 1-7

Adeonellopsls transverse Canu and Bassler, 1920, p. 566, pi. 15, figs. 11-19.

Diagnosis. Small, somewhat rhombic to olavlform zooecla; ascopore area small with a few stellate pores; trans versely oriented suboral avlcularium placed on and occupying essentially the entire margin of secondary orifice, often contacting its lateral margins; distal avicularla absent, lateral and proximal avicularla Infrequent; peristome with out hood; gonoecia not found.

Occurrence. Middle Eocene (Claiborne), Lisbon

Formation and Gosport Sand, Alabama; Upper Eocene (Jackson),

Moodys Branch Marl, Alabama and Mississippi.

Material studied. Lectotype (here designated)

USNM 63856 (Canu and Bassler, 1920, pi. 15, fig. 22), para- lectotypes USNM specimens (1920, pi. 15, figs. 20-22, 25,

26), 13 specimens, Lisbon Formation, Gosport Sand and Moodys

Marl, Alabama and Mississippi (Sampling Units 2, 3A, 30, 31).

Description. Zoarlum erect, frond-like, compressed, broad, bilaminate; laminae moderately thick; zooecla arranged in longitudinal rows on either side with those of adjacent rows alternating position.

Zooeoia small, rhombic to claviform, especially in frontal aspect, separated by shallow furrow; marginal zooecla 101 little distinct from central ones; older generation zooecla

Indistinct, although a circular, shallow pit may mark former oral region.

Frontal wall moderately thick, becoming quite thick, reticulate and featureless with age. Total area rim dis tinct, tapering proximally, thinner but not elevated distally.

Areolae Bmall, distinct and marginal around entire zooeclum.

Calcification develops bulbous tubercles along total area rim, especially proximally. In still older zooecla, these seem to disappear with further thickening of the wall and even to be replaced by a series of pits.

Orifice large, seral-elllptical, proximal margin straight. Secondary orifice large, more oval, somewhat in dented at proximal-lateral margins around suboral avlcu- larlum and bordered proximally by suboral bar. Peristome thick, moderate to long, without major structures or distal hood.

Suboral avlcularium long, sub-triangular, positioned on proximal margin of secondary orifice on and largely cov ering suboral bar, oriented transversely with rostrum fre quently contacting margins of secondary orifice. Distal avicularla lacking; single, round, lateral or proximal avlcu larium infrequent, more common on old zooecla.

Ascopore area a small, slightly depressed, some what circular pit set close to peristome and containing 3-A small, stellate or semi-stellate pores. Entrance to ascopore area oircular, but constricted and occluded with age. 102

Remarks. Canu and Bassler reported numerous Irregu larities for this species, but such variations are considered here to be ontogenetic in nature as general characteristics are uniform. The ascopores are more semi-stellate than stel late as previously reported, as the denticles are inconsistent in number and form. Although stressed in the earlier descrip tion, no ascopore was observed to open into the peristome.

No gonoecia were observed.

ADEONELLOPSIS QUISENBERRYAE

Canu and Bassler, 1920

Plate IV, Figures 1-8

Adeonellopsls Qulsenberrvae Canu and Bassler, 1920, p. 566, pi. 15, figs. 20-26 .

Diagnosis. Medium-size, elongate zooecla marked by a well-defined total area rim, noticeably constricted medially; moderate-size ascopore area containing usually 5-6 striking, stellate pores; an elongate, distally directed suboral avicularium subjacent to oral area; additional avicularla are in frequent, no peristome hood is present and gonoecia are not found.

Occurrence. Middle Eocene (Claiborne), Gosport Sand,

Alabama,

Material studied, Lectotype (here designated) USNM

63857 (Canu and Bassler, 1920, pi. 15, fig. 26), paralecto- types USNM specimens (1920, pi. 15, figs. 22, 23, 25), 26 specimens, Gosport Sand, Alabama (Sampling Unit 3). 103

Description. Zoarium erect, robust, frond-like,

branching, bilaminate with broad base. Laminae thick, wide,

with zooecia alternating in 10-15 longitudinal rows in each

lamina.

Zooecia moderate-size, elongate, irregularly rectangu

lar to coffin-shaped, distinct, but little separated by fur

rows. Marginal zooecia similar to central ones.

Frontal wall moderately thick, increasing in thick

ness and becoming almost featureless with age. Total area

rim elongate, elliptical in outline, and noticeably constricted

near suboral avlcularium. Areolae distinct, more rounded

in distal areas, larger and more elongate in proximal ones;

margining entire zooeciura. Few extra areolae occasionally near proximal ends of frontal. Some bulbous projections on

total area rim.

Orifice moderate in size, semi-elliptical; proximal margin straight and bordering a distally slanting basal

shelf. Secondary orifice more rounded. Suboral bar wide, but indistinctly set off from peristome. Peristome thick, of moderate length, and without distal hood.

Suboral avlcularium long, prominent, triangular, distally directed, positioned centrally below secondary orifice with rostrum frequently projecting into proximal part of secondary orifice. Distal and lateral avicularla

typically lacking, but a large rounded or subtriangular proximal avlcularium is present on many old individuals. 104

Ascopore area of moderate size, distinct, set far

from proximal margin of secondary orifice. Area subtrlangu-

lar and elongated in proximal-distal direction, well depressed

below frontal surface and pierced by 5-7 distinctly stellate

pores.

Remarks. Evidently describing an older specimen,

Canu and Bassler reported a little visible cribriform area

and a suboral avlcularium in contact with one of the lateral walls. The ascopore area is distinct on '’mature” zooecia

and contains several well-developed stellate pores with

prominent denticles. The small, uniporous ascopore area discussed by Canu and Bassler is not present. Although the rostrum may touch a side wall in some individuals, the promi nent suboral avlcularium typically makes no such contact, but does often reach (or even project into) the proximal part

of the secondary orifice. Of all forms studied in the Ameri

can deposits, the frontal wall of this species is the thick

est. The earlier workers reported A. qulsenberryae from the

Jackson, but it was not present in such samples collected here.

ADEONELLOPSIS CYCLOPS

Canu and Bassler, 1920

Diagnosis. Zooecla medium to small size, irregularly

rectangular to clavlform; total area rim tapers proximally

to merge and form a narrow, central ridge; ascopore area

moderate-size with 2-5 semi-stellate pores; suboral aviculariura 105 positioned on suboral bar in proximal margin of secondary orifice and variously directed; small distal and large proxi mal avioularium common; distal part of peristome elevated to form a convex hood; gonoecia numerous, prominent, large.

Occurrence. This species includes the following sub species :

oyclops cyclops: Eocene (Jackson) and

Oligocene (Vicksburg), Alabama, Mississippi,

and Florida (Pachuta Marl to Marianna Lime

stone).

2. A. oyclops X! Lower Oligocene (Vicksburg),

Georgia (Cooper Marl).

ADEONELLOPSIS CYCLOPS CYCLOPS

Canu and Bassler, 1920

Plate VI, Figures 1-6

Plate VII, Figures 1-7

Adeonellopsls cyclops Canu and Bassler 1920, p. 570, pi. 100, figs. 1-11.

Adeonellopsls grandls Canu and Bassler 1920, p. 568, pi. 99, figs. 11-18.

Diagnosis. Zooecia moderate-size; central proximal ridge distinct; ascopore area elongate and somewhat removed from oral area, typically with 3-5 semi-stellate pores; peri stome with distlnot but moderate-size hood, gonoecia similar to but larger than zooecia, wider proximally; ascopore area with 10-20 semi-stellate pores. 106

Occurrence, Eocene (Jackson), Pachuta Marl and

Shubuta Clay, Alabama; Oligocene (Vicksburg), Red Bluff Clay,

Alabama, Marianna Limestone, Alabama, Mississippi and Florida,

Crystal River and Bumpnose Limestone, Florida, Mint Spring

Marl, Alabama,

Material studied, Lectotype (here designated)

USNM 64321 (Canu and Bassler, 1920, pi, 100, fig. 11), para- lectotypes USNM specimens (1920, pi, 100, figs. 2-10; pi. 99, figs. 12-15), 815 specimens, Pachuta Marl to Marianna Lime stone, Alabama, Mississippi and Florida (Sampling Units

6-23, 32).

Description, Zoarium erect, elongate, somewhat thin and fragile, compressed, bifoliate, dichotomously branching; laminae narrow with 6-8 rows of zooecia on either side, zooecia in adjacent rows alternating in position; colony base thicker, more cylindrical.

Zooecla moderate-size, elongate, Irregularly rec tangular to claviform; marginal zooecla distinct, more regu lar in shape and somewhat longer than central ones with frontal surface features weakly developed.

Frontal wall somewhat thin, but thickening and show ing fewer features with age; total area outline long oval, tapering proximally to form narrow proximal ridge near base of zooecium; total area rim projecting frontally in distal area of zooecia to form moderate convexity or hood above peristome. Marginal areolae generally rounded, more elliptical and distinct proximally, lateral areolar rows subparallel in proximal areas. 107

Orlfloe moderate-size, semi-elliptical; proximal border straight; secondary orifice somewhat larger, less regular and rounded in outline; suboral bar with short dis tal denticle present at proximal margin of secondary orifice; peristome of moderate length with moderate cap or hood.

Suboral avlcularium rounded, often laterally or dis tally directed and positioned on suboral bar at proximal margin of orifice, often obscuring it. Small distal avicularlum frequent on peristome cap; large rounded avlcularium common and prominent at base of many older individuals and often projecting above frontal surface.

Ascopore area sub-triangular, little depressed but elongated, somewhat removed from oral region, typically con tains 3-5 semi-stellate pores.

Gonoecia broad, elongate, larger than zooecia, numer ous, prominent, swollen, often clustered; ascopore region convex with 10-20 semi-stellate pores; secondary orifice wide but short; peristome hood prominent and distal avicularla frequent.

Remarks. Colonies of this assemblage are frequent and prominent in upper Eocene and Oligocene strata of the central Gulf Coast area. Canu and Bassler (1920) established two morphospecies, A. grandls and A, cvclops in this complex.

The former was characterized primarily by a single zooecial ascopore and a large distal pore (avlcularium), whereas the latter taxon was distinguished by them on the basis of a cribriform area on both zooecia and gonoecia together with a 108

thin peristome convexity. No specimens were studied exhibit

ing the single ascopore. Although some specimens superfi

cially appeared to possess a single ascopore, below this

opening is a cribriform region with stellate pores. Onto

genetic change apparently constricts this region relatively

early in some colonies, but both conditions, closure and a

multiple ascopore area, are not infrequent among "mature"

individuals on the same zoarial fragment.

A small distal avlcularium and a larger proximal

one are also common throughout this complex on both zooecia

and gonoecia. Gonoecia are large, prominent and may exhibit

as many as 20 stellate ascopores. Canu and Bassler made no

mention of these individuals in their description of A.

cyclops although their figured specimens show numerous gonoecia.

Considerable overlap in morphologic variation exists

between the two original morphologic species and they are

here considered as a single, if somewhat variable, assemblage.

This subspecies differs from A. cyclops X in having larger,

more elongate zooecia and gonoecia with a moderate peristome hood, a distinct, thin, proximal ridge separating sub-parallel

rows of areolae, more frequent proximal avicularla and more numerous gonoeclal ascopores.

ADEONELLOPSIS CYCLOPS "X," n. subsp.

Plate V, Figures 1-7

Diagnosis. Zooecia small, wide, squat, irregularly

rectangular to rhombic in outline; total area ovate in 109 outline, central proximal ridge short, Indistinct; ascopore area small, set in close to oral area and contains 2-3 small pores; peristome hood slight, but frequently with small distal avlcularium; lateral and proximal avicularla infrequent, gonoecia much larger than zooecia with large prominent asco pore area containing 8-10 pores.

Occurrence. Oligocene (Vicksburgian) Cooper Marl,

Georgia.

Material studies, Holotype, USNM specimen, paratypes

USNM specimens, 6 specimens, all from Cooper Marl.

Description. Zoarium erect, bifoliate, branching, moderately thick; laminae slightly convex, each side with

6-12 zooeclal rows with zooecia of adjacent rows alternating in position.

Zooecia small, broad, irregularly rectangular to rhombic; marginal zooecia longer with a less distinct asco pore region, otherwise not strongly differentiated from cen tral ones.

Frontal wall moderately thick, becoming thicker and featureless with age. Total area ovate in outline, tapering proximally; rim prominent, thick but proximal central ridge short, indistinct; rim elevated distally to form slight peristome hood. Areolae marginal, rounded, little distinct.

Secondary orifice small, serai-elliptical, margined proximally by suboral bar. Peristome thick with indistinct denticle distal to and slightly below suboral bar. 110

Suboral avlcularium of moderate length, sub-rounded, oriented predominantly distally, but varying from distally to laterally; positioned at proximal margin of secondary orifice margins but often projecting upward from the bar.

Small, rounded distal avlcularium not uncommon on reduced peristome oap, lateral avicularla on line of marginal areolae normally absent; rounded, weak, avlcularium at proximal margin of some individuals.

Ascopore area small, sub-triangular, set close to sec ondary orifice but at shallow depth below frontal surface;

2-3 small stellate pores present with a few unequal, incom plete denticles.

Gonoecia distinct, swollen, much larger than zooecia, oral dimensions moderate, frequently clustered in groups of

3 or more; rounded distal avlcularium common on distinct but slight peristome hood; asocpore area large but somewhat con vex and contains 8-10 somewhat stellate pores,

ADEONELLOPSIS GALEATA

Canu and Bassler, 1920

Plate VIII, Figures 1-4

Plate IX, Figures 1-4

Adeonellopsls galeata Canu and Bassler, 1920, p. 568, pi. 99» figs. 1-10.

Diagnosis. Zooecla moderate size to large, irregu larly rectangular; ascopore small, sub-triangular with 2-4 stellate pores; small, round, suboral avlcularium in center Ill of suboral bar; oral denticle distinct; medlum-slze distal avlcularium and a large proximal avlcularium frequent; peri stome hood prominent, large; gonoecia slightly larger than zooecla, numerous; ascopore area moderate size with 8-16 semi-stellate pores; peristome hood well-developed.

Occurrence. Oligocene (Vicksburg), Glendon Limestone and Byram Marl, Alabama and Mississippi.

Material studied. Lectotype (here designated) USNM specimen (Canu and Bassler, 1920, pi. 99, fig. 2), paralecto- types USNM 64318 (1920, pi. 99, fig0 * 3-7), 138 specimens,

Glendon Limestone and Byram Marl, Alabama and Mississippi

(Sampling Units 24-29).

Description. Zoarium erect, elongate, bifoliate, compressed but somewhat thickened, branching zooecia on both sides of branches in 6-8 longitudinal rows with zooecla of adjacent rows alternating with each other.

Zooecla moderate-size to large, irregularly rectangu lar; marginal zooecia longer, fatter, with less frontal dif ferentiation and distal portion projecting somewhat laterally.

Frontal wall moderately thick, becoming thicker but losing surface differentiation in older individuals. Total area a long oval defining rim tapering proximally but not extending to end of zooecium; rim thinner at distal margin and projecting upward and proximally to form prominent peri stome hood. Marginal areolae rounded, distinct, often con verging to a distinct point; sometimes a few extra areolae in proximal area. 112

Orifice semi-elliptical; proximal border straight; secondary orifice more variable and rounder; suboral bar borders seoondary orifice proximally and exhibits a broad oral denticle just distal to and below suboral avlcularium.

Peristome moderately thick and deep.

Suboral avlcularium small, rounded, variously directed and positioned on center region of suboral bar. A medium sized distal avlcularium (on peristome hood) and a larger round proximal avlcularium are frequent; lateral avicularla on the line of areolae are occasionally present.

Ascopore area a small, little elongated, sub- triangular pit set close to peristome, but only slightly depressed below frontal, containing 2-4 small pores with incomplete and unequal denticles.

Gonoecia slightly larger than zooecia, broad, num erous, moderate size, wide oval in outline, prominent, possess ing a well-developed peristome hood. Suboral avlcularium small, not filling all space on supporting suboral bar.

Distal and proximal rounded avicularla as on zooecla. Asco pore sub-triangular, moderate size and perforated by 8-16 semi-stellate pores.

Remarks. Canu and Bassler distinguished this species primarily on the basis of the prominent zooecial convexity or hood. Distal and lateral avicularla are frequent, but not constant on all individuals as earlier indicated. An oral denticle is more conspicuous and larger than it is in the A. oyclops assemblage. The rare occurrences of this species in the Marianna and Red Bluff formations reported by Canu and Bassler evidently represent morphologic varia tion in the A. ovolopa complex which was incorrectly inter preted. Gonoecia are conspicuous but they were omitted from the earlier description. BIBLIOGRAPHY

Andersen, H. V., I960, Geology of Sabine Parish: Louisiana Geol. Survey Bull. 34, 164 p.

Adanson, M., 1763, Families des plantes; vol. 1: Paris Vincent, 190 p.

Bandy, 0. L., 1949, Eocene and Oligocene Foraminifera from Little Stave Creek, Clarke County, Alabama: Bull. Am. Paleontology, vol. 32, 210 p.

Barnes, R. D., 1968, Invertebrate zoology, 2nd ed.: Philadelphia, V/. B. Saunders Co., 743 p.

Barrington, E. J. W., 1967, Invertebrate structure and function: Boston, Houghton Mifflin Co., 549 P.

Bassler, R. S., 1953, Bryozoa JLn Treatise on invertebrate paleontology, Part G: Lawrence, Kansas, Kansas Univ. Press and Geol. Soc. America, 253 p.

Beerbower, J. L., 1968, Search for the past— an introduction to paleontology, 2nd ed.: Englewood Cliffs, N. J. Prentice-Hall Inc., 512 p.

Boardman, R. S., and Cheetham, A. H., 1969, Skeletal growth, intracolony variation and evaluation in Bryozoa— a review: Jour. Paleontology, vol. 43, p. 205-233

Boardman, R. S., Cheetham, A. H. and Cook, P. L., 1969, Intracolony variation and the genus concept in Bryozoa: Proceedings North American Pal. Conven tion, Part C, p. 294-320.

Brown, D. A., 1952, The Tertiary Cheilostomatous Polyzoa of New Zealand: British Museum (Nat. Hist.), London, 405 P.

Cain, A. J., 1954, Animal species and their evolution: New York, Harper and Row, 190 p.

Cattell, R. B., 1952. Factor Analysis: New York, Harper and Brothers, 462 p.

Canu, F. and Bassler, R. S., 1920, North American early Tertiary Bryozoa: U. S. Natl. Mus. Bull. 106, 879 P., 162 pis. 115 Chawner, W. D., 1936, Geology of Catahoula and Concordia Parishes: Louisiana Geol. Survey Bull. 9» 232 p.

Cheetham, A. H., 1957, Eocene-Oligocene boundary, eastern Gulf Coast region: Gulf Coast Assoc. Geol. Soc. Trans., vol. 7, P. 89-97.

• 1963, Late Eocene zoogeography of the eastern Gulf Coast region: Geol. Soc. America Mem. 91, 113 p.

-» 1966, Cheilostomatous Polyzoa from the Upper Bracklesham Beds (Eocene) of Sussex: Bull. Brit. Mus. Nat. History, Geology, vol. 13, P. 1-115.

- » 1968, Morphology and systematics of the bryozoan genus Metrarabdotos: Smithsonian Misc. Coll., vol. 153, no. 1, 121 p., 18 pis.

Cheetham, A. H., and Deboo, P. B., 1963, A numerical index for bioptratigraphic zonation in the mid-Tertiary of the eastern Gulf: Gulf Coast Assoc. Geol. Soc., Trans., vol. 13, p. 139-14-7.

Cheetham, A. H., and Glawe, L. N., 1964, Jackson-Vicksburg type sections _in Guidebook for field trips: South eastern Section, Geol. Soc. America, 1964 Annual Mtg. p. 1-12.

Cheetham, A. H., Rucker, J. B., and Carver, R. E., 1969, Wall structure and mineralogy of the cheilostome bryozoan Metrarabdotos: Jour. Paleontology, vol. 43, P. 129-135.

Cooke, C. W., 1926, Geology of Alabama: the Cenozoic forma tions: Ala. Geol. Survey Spec. Report 14, p. 251- 297.

Deboo, P. B., 1965, Biostratlgraphic correlation of the type Shubuta Member of the Yazoo Clay and Red Bluff Clay with their equivalents in southwestern Alabama: Ala. Geol. Survey Bull. 80, 84 p.

Eades, D. C., 1965, The inappropriateness of the correlation coefficient as a measure of taxonomic resemblance: Sys. Zoology, vol. 14, p. 98-100.

Eames, F. E., Banner, F. T., Blow, W. H., and Clarke, W. J., 1962, Fundamentals of mid-Tertiary stratigraphical correlation: Cambridge, Cambridge Univ. Press, 163 p. 116

Ehrlich, P. R., and Holm, R. W., 1963, The process of evolution: New York, McGraw-Hill Co., 347 p.

Ehrlich, P. R., and Raven, P. H., 1969* Differentiation of populations: Science, vol. 165> P. 1228-1232.

Gardner, J. A,, 1957, Little Stave Creek, Alabama— Paleo- eoologic study jLn Ladd, H. S., ed., Treatise on marine ecology and paleoecology, vol. 2, Paleo- ecology: Geol. Soc. America Mem. 67, vol. 2, p. 573-588.

George, '. N., 1956, Biospecles, chronospecles and morpho- specles, In Sylvester-Bradley, P. C., ed., The species concept In paleontology: Systematica Assoc. Pub. no. 2, p. 123-137.

Gilmour, J. S. L., 1937, A taxonomic problem: Nature, vol. 139, P. 1040-1042.

Glawe, L N., 1969 Peoten nerplanus stock (Ollgocene) of the southeastern United States: Ala. Geol. Survey Bull. 91, 179 P.

Harmer, i . P., 1902, On the morphology of the Cheilostomata: Quart. Jour. Micr. Sci., London, vol. 46, p. 263- 250.

1957, The Polyzoa of the Siboga Expedition, pt. 4, Cheilostomata Ascophora II: Siboga Expedition Repts. vol. 28d, p. 691-1145.

Hazel, J E., 1970, Binary coefficients and clustering in biostratigraphy: Geol. Soc. America Bull., vol. 81, p. 3237-3252.

House, M R., 1971, Evolution and the fossil record in Gass, I. G ., Smith, P. J., and Wilson, R. C. L., eds., Understanding the earth: Cambridge, MIT Press, p. 193-211.

Howe, H. V., 1933, Review of Tertiary stratigraphy of Louisiana: Am. Assoc. Petroleum Geologists Bull., vol. 17, no. 6, p. 613-655.

1942, Fauna of the Glendon Formation at its type locality: Jour. Paleontology, vol. 16, no. 2, p. 264-271.

Imbrle, 1957, The species problem with fossil animals, In Mayr, E., ed., The species problem: Am. Assoc. Adv. Science Publ. no. 50. 117 Ivey, J. B., 1957, Geology and groundwater in the Monroeville area, Alabama: Ala. Geol. Survey Bull. 66, 116 p.

Johnson, R. G., 1962, Interspecific associations in Pennsyl vanian fossil assemblages: Jour. Geology, vol. 70, P. 32-55.

Kummel, B., 1970, History of the earth— an introduction to historical geology, 2nd ed.: San Francisco, W. H. Freeman, 707 P.

Levinsen, G. M. R., 1909, Morphological and systematic studies on the chellostomatous Bryozoa: Copenhagen, Nat. Forfatt, Forlag, 431 p.

MacGillivray, P. H., 1886, Descriptions of new or little known Polyzoa: Trans. Proc. Roy. Soc. Victoria, vol. 22, p. 128-139.

MacNeil, F. S., 1944, Oligocene stratigraphy of the south eastern United States: Am. Assoc. Petroleum Geologists Bull., vol. 28, no. 9, P. 1313-1354.

Mayr, E., 1940, Speciation phenomena in birds: Amer. Natural ist, vol. 74, p. 249-278.

______, 1963, Animal species and evolution: Cambridge, Mass., Harvard Univ. Press, 718 p.

, 1969, Principles of systematic zoology: New York, McGraw-Hill Co., 434 p.

McGlothlin, T., 1944, General geology of Mississippi: Am. Assoc. Petroleum Geologists Bull., vol. 28, no. 1, p. 29-62.

McGulrt, J. H., 1941, Louisiana Tertiary Bryozoa: La. Dept. Conserv. Geol. Bull. 21, 177 P.

Mettler, L. E. and Gregg, T. G., 1969, Population genetics and evolution: Englewood Cliffs, N. J., Prentice- Hall Inc., 212 p.

Mississippi Geological Society, 1948, Upper Eocene, Oligocene and lower Miocene of central Mississippi: sixth field trip guidebook: Jackson, Mississippi, 69 p.

Mississippi Geological Society, 1952, Claiborne of west Alabama and eastern Mississippi: ninth field trip guidebook: Jackson, Mississippi, 87 P.

Mississippi Geological Society, I960, Cenozoic of south eastern Mississippi and southwestern Alabama: fifteenth field trip guidebook: Jackson, Missis sippi, 48 p. 118

Moore, R C., et al. 1968, Development, trends and outlooks In paleontology: Jour. Paleontology: vol. 42, p. 1327-1377.

Monroe, 1 r. H., 1954, Geology of the Jackson area, Mississippi: U. S. Geol. Survey Bull. 986, 133 p.

Murray, ir . E., 1947, Cenozoic deposits of the central Gulf Coastal Plain: Am. Assoc. Petroleum Geologists Bull. vol. 31, no. 10, p. 1825-1850.

1961, Geology of the Atlantic and Gulf Coastal province of North America: New York, Harper & Brothers, 692 p.

Newell, '. D., 1956, Fossil populations, in Sylvester- Bradley, P. C., ed., The species concept in paleontology: Systematlcs Assoc. Pub. no. 2, p. 63-82.

Park, R. A., 1968, Paleoecology of Venerlcardla sensu lato (Pelecypoda) in the Atlantic and Gulf Coastal province— an application of paleosynecologic methods: Jour. Paleontology, vol. 42, p. 955-986.

Purl, H. S., and Vernon, R. 0., 1964, Summary of the geology of Florida and a guidebook to the classic exposures: Florida Geol. Survey Spec. Pub. 5 (revised), 312 p.

Raup, D. H,, and Stanley, S. M., 1971, Principles of paleon tology: San Francisco, W. H. Freeman, 388 p.

Rucker, . B., 1967, Paleoecologlcal analysis of cheilostome Bryozoa from Venezuela--Brltish Guiana shelf sediments: Bull. Marine Sci., vol. 17» p. 787-839.

1969, Skeletal calcification of some cheilostome Bryozoa, in Proceeding of the first International Bryozoology Association conference, Milan, Italy: Atti. Soc. Italiana Sci. Nat. Milano, vol. 106.

Rucker, '. B., and Carver, R. E., 1969, A survey of the carbonate mineralogy of cheilostome Bryozoa: Jour. Paleontology, vol. 43, p. 791-799.

Russell, R. J., 1955, Guides to southeastern geology: New York, Geol. Soc. America, 592 p.

Schopf, \ J. M., and Allan, J. R., 1970, Phylum Ectoprocta, Order Cheilostomata— raicroprobe analysis of cal cium, magnesium, strontium and phosphorus in skeletons: Science, vol. 169, P. 280-282. 119

Shaw, A . B., 1969, Adam and Eve, paleontology, and the non objective arts: Jour. Paleontology, vol. 43, p. 1085-1098.

Simpson, G. G., 1961, Principles of animal taxonomy: New York, Columbia Univ. Press, 247 P.

Sokal, R R., and Sneath, P. H. A., 1963, Principles of numerical taxonomy: San Francisco, W. H. Freeman, 359 P.

Stuckey, C. W., i960, A correlation of the Gulf Coast Jack son: Gulf Coast Assoc. Geol. Socs. Trans., vol. 10, p. 285-298.

Thomas,

Toulmin, L. D., 1955, Cenozoic geology of southeastern Alabama, Florida and Georgia: Am. Assoc. Petroleum Geologists Bull., vol. 39, no. 2, p. 207-235.

1962, Geology of the Hatchetigbee anticline area, southwestern Alabama, Little Stave Creek— Salt Mountain field trip: Gulf Coast Assoc. Geol. Societies guidebook, 12th Ann. Mtg., p. 1-46.

Wilhert, L. J., 1951, Faunas and facies in the upper Eocene of Arkansas: Gulf Coast Assoc. Geol. Soc. Trans., vol. 1, p. 122-133. APPENDIX REGIONAL GEOLOGY AND STRATIGRAPHY

General Geologic Relationships

Widespread Cenozoic deposits are present In the

Gulf Coastal Plain, and these sediments have probably been more extensively studied than those of any other geologio province in North America, Stratigraphic, paleontologlo and paleoecologic variation is expressed in deposits which are predominantly sands, silts, clays, marls, and limestones.

Exceptionally thick Tertiary and Quaternary units continue a general pattern of deposition in the Gulf coastal region which apprently was first established in the Jurassic. The cyclical sequence of the Cenozoic beds indicates a number of major transgressions and regressions, although these seas were not as extensive across the area as those of Cretaceous time. Sedimentation rates were high however, and estimates are reported (Kummel, 1970) indicating some 300,000 cubic miles of Cenozoic sediments in the emerged portion of the ooastal plain from Georgia to Mexico.

This seaward-thickening wedge is a heterogeneous asso ciation of lithosomes and biosomes indicative of various deltaic, coastal, fluviatile and marine conditions. It was along the thin edges of the deltaic blankets and along the shifting shorelines and in the shoaling and deeper waters associated with the development of this complex that many 122 of the units observed In this study were formed. These areal geologic variations ocour as parts of the regional Cenozoic pattern which Implies that marine and deltaic sedimentation alternated In two significant cycles (Murray, 1947). Early marine deposits plus later pro-deltaic sedimentation charac terize the Lower Eooene (Wilcox). A decrease in delta building occurred during the middle Eocene (Claiborne) and such activity had essentially ceased during the quiescent upper Eooene (Jackson) and marine sediments of this age are frequent in the central Gulf Coast. Oligocene (Vicksburg) strata, also Indicative of quiet, stable conditions, repre sent the close of significant, extensive marine sedimentation in the oentral Gulf area. Deltaic realms were reestablished in the Miocene initiating a second interval of this type of activity which has continued to the present day.

Lithostratigraphic Units

The Eocene and Oligocene deposits crop out in a nearly continuous, but narrow, inland belt which somewhat parallels the present coastline from northern Florida to Texas. Fig ure A-l shows the major lithostratigraphic units which were observed and sampled. No attempt is made here to define extensively or describe these formations as both general and specific accounts of local and regional stratigraphic relationships involving rock and tlme-rook units have been prepared (Andersen, I960; Chawner, 1936; Cooke, 1926; Howe,

1933; MacNeil, 1944; MoGlothlin, 1944; Murray, 1947, 1961; FIGURE A-l

General correlation chart for lithostratigraphic units in study area. NE Lou i s i ana Mississippi A I a bama N Florida Ga . Ch i c ka sawhay Ch i cka sawhay ______L s . Rosef i eId Bucat u n na Bucatun na Fm. Clay______Clay______Byram Marl Byram Marl Suwannee L s . Rosef i eId GIendon Ls. Glendon Ls. Marl Marianna

Sa nd e I Ls . Ma r i a n na Ls . Sand Mar i anna Mint Ls . Spring

Mo sIey Forest H i U J / * ^ Sa nd ^ / ^ ^ ^ Bump nose Cooper Red Bluff Clay L s . Ma r I

S h u b u t a Clay Land i ng Beds CrystaI MarlPachuta River Ls .

Y a zoo Clay Cocoa Sand

North Tw i stwood Creek Clay

Ls . Moodys Marl Moodys Branch Mar

Cockfield Fm. Coc kf i eId Gosport F m . Sand Cook Mounta i n Wautubbee Lisbon F m . Ma r I F m .

Tall a hatta F m .

Ba s h i Marl Salt Mounta i n L s . 125

Puri and Vernon, 1964; Russell, 1955; Stuckey, I960; Toulmin,

1955» 1962; Wilbert, 1951). Many of these units are lithologi- oally heterogenous exhibiting compositional variations and reflecting changes in depositional environments. Brief, summary-type lithologio descriptions are provided at the end of this discussion, however, for those units which contain

Adeonellopsls.

A variety of faunas and faunal associations are pres ent in these rocks, and molluscs, echlnoids, bryozoans, ostra- codes and foraminifers are common. These fossil aggregates have been studied in various ways and in varying detail by a number of investigators as stated earlier.

Geologic relationships are especially variable in the area of western Alabama and eastern Mississippi adjacent to the Eocene-Oligocene boundary. This particular area, which contains a number of classical sections, was extensively sampled. Disconformities, diastems and faunal discontinui ties often mark these exposures. Also, the strata associated with the Jackson-Vicksburg sequence here are not in standard, simple, vertical sequence and facies changes are numerous and involved. Figure A-2 shows the general facies relation ships present in this geographic region.

Although no complete stratigraphic synthesis is pre sented for these beds, this does not imply that correlation, zonation and subdivision problems, lithostratigraphic and biostratigraphic, are non-existent. Questions concerning

Oligocene strata, the nature and position of the Jacksonian- FIGURE A-2

Diagram of generalized Eooene-Oligocene facies relationships in southeastern Mississippi and southwestern Alabama. e i sISSIP ALABAMA SeriesMISSISSIPPI Paynes Hammock Sand MIOCENE Chickasawhay Limestone Buca + u nna

By ram Clay Mar I

GIendon L i mestone OLIGOCENE M i nt Marianna Spring

Limestone

Forest Hill Sand

Red Bluff Clay and Mar I

Shubuta Clay and Ma r

Ma r I

Pachuta. Cocoa Sand

EOCENE North Twistwood Creek Clay

Moodys Branch Ma r I

Gosport Sand 128

Vlcksburglan boundary and the Eocene-Oligocene boundary are especially Intriguing (Eames and others, 1962; Cheetham,

1957; Cheetham and Deboo, 1963; and Deboo, 1965). GENERAL LITHOLOGIC DESCRIPTIONS

Byram Marl: A gray-green and buff, fossiliferoua marl with

some glauconite, quartz sand and clay. Approximately

25 feet thick In western Mississippi but thins to 1

or 2 feet In places in western Alabama where It ls also

less detrital. Overlies the Glendon Limestone.

Glendon Limestone: An extensive, greenish-white and buff

limestone and marl with some calclte and quartz sand

and fossils. Overlies the Marianna Limestone In Florida

and Alabama and the equivalent Mint Spring Marl In Missis

sippi. About 35 feet thick near Vicksburg, but becomes

thinner and less detrital eastward.

Rosefield Marl: The general equivalent of the Glendon and

Mint Springs beds in northeast Louisiana. Clay, sand and

marl with frequent shell-hash or coquina zones. Beds are

generally thin and colors vary from gray and buff to brown.

Marianna Limestone: Massive, cream and white, somewhat soft

and homogeneous, fosslllferous limestone which discon-

formably overlies the Red Bluff Clay in Alabama. Attains

a maximum thickness of 80 feet in south-central Alabama

but thins westward in Mississippi where it overlies the

Mint Spring Marl and eastward to Florida where it overlies

the Bumpnose Limestone. Lepldocycllna is common. 130

Mint Spring Marl: A very fossiliferous, blue, gray and

green marl with glauconite and quartz sand whloh discon-

formably overlies the Forest Hill Sand In Mississippi.

Unit ls about 20 feet thick near the Mississippi River

but thins eastward, pinching out near the Alabama border.

Red Bluff Clay: Fossiliferous gray-green clay and marl,

about 20 feet thick near Hlwannee, Mississippi, which

thins to about 8 feet of green and buff, calcareous,

glauconitic clay and marl in south Alabama. It overlies

the Shubuta clays in Mississippi and Alabama.

Bumpnose Limestone: The general Red Bluff equivalent In

southeastern Alabama and northwestern Florida. A cream,

gray and white, powdery limestone, moderately Indurated,

and containing abundant large orbitoid foraminlfers,

especially Lepldocvollna. Disconformable on underlying

Crystal River Limestone. Thickness Is about 15 feet.

Cooper Marl: Red-Bluff/Bumpnose general equivalent in south

Georgia. Buff and gray, fosslliferous clay and marl with

some sandy layers.

Shubuta Clay: A light gray-green fosslliferous clay which

is some 70 feet thick near Shubuta, Mississippi but thins

to about 7 feet of buff, gray and green marl near Perdue

Hill, Alabama. Overlies Paohuta Marl.

Pachuta Marl: A white, tan and gray fosslliferous sandy

marl. Unit ranges from 5 to 10 feet in thlokness between

its western limits near the MissiBsippl-Alabama line and 131

Its eastern limits near Perdue Hill, Alabama. Overlies

Coooa Sand.

Danville Landing Beds: General equivalent of Shubuta unit

in northeastern Louisiana. Green, brown and gray marl

and clay with fossils. Poorly exposed In type area.

Crystal River Limestone: Buff to white coquina-like cal-

carenite and limestone, moderately Indurated. Local

soft pockets are fossiliferous. Approximately 120 feet

thick. Asterocvollna common. Upper part only is exposed

in study area,

Moodys Branch Marl: Rust yellow to blue, gray and buff,

fosslliferous sand and clay interbedded with thin white

and gray argillaceous limestone. Dieconformably overlies

Cockfield Fm. or Gosport Sand and ls about 24 feet thiok.

Gosport Sand: A rather ooarse glauoonitic and ferruginous,

gray, brown and green quartz sand with concretionary

layers and shell concentrate zones. The unit is about

20 feet thick and disconformably overlies the Lisbon Fm.

in the Alabama area.

Lisbon Formation: A very heterogeneous unit some 150 feet

thick in southwestern Alabama. Predominantly clay and

sand although marl, limestone and silt beds are common,

all varied green, brown, tan, gray and blue in color.

Lignitic, concretionary, glauconitic and fosslliferous

zones (especially Ostrea) are frequent. Overlies the

darker Tallahatta clays. 132

Bashl Marl: The lower member of the Hatchetigbee Formation.

A mottled yellow, olive green and brown, glauconitic

sand with minor clay zones. Fosslliferous, somewhat hard,

sand and marl boulders ocour in basal part of the unit

which ls about 15 feet thick in western Alabama. SAMPLE LOCATIONS

For each location designation shown, the last digit specifies the number of samples obtained at that locality.

Formations exposed are enclosed by parentheses. The specific samples containing Adeonellopsls specimens are listed. An asterisk indicates those locations where all samples were void of desired zoarial fragments. Supplementary locations are indicated by letters. Although there is some overlap with other localities, Smithsonian samples are listed as separate locations for clarity. A total of forty-two sep arate locations are shown.

Primary Locations

Location 1-3. Sam Smith's quarry, Jackson County, Florida.

Section described in Purl and Vernon, 1964, p. 90 (Marianna

Ls., Bumpnose Ls., Crystal River Ls.).

Marianna Ls.: Sample 1 Ma 01, 10 feet above base, east

quarry pit.

Location 2-4*. Springfield Church quarry, Jackson County,

Florida. Section described in Puri and Vernon, 1964,

Stop 20 (Crystal River Ls.).

Location 3-2. Road cuts and stream banks, U.S. 90 bridge

over Chipola River at Marianna, Jackson County, Florida.

Section described in Puri and Vernon, 1964, Stop 26 134

(Marianna Ls., Bumpnose Ls., Crystal River Ls.).

Marianna Ls.: Sample 3 Ma 01, 35 feet above base.

Location 4-2*. Falling Waters Sink State Park, Washington

County, Florida. Section described in Puri and Vernon,

1964, p. 114 (Tampa Ls., Suwannee Ls.).

Location 5-4. Road cut on County road 23, 3.5 miles NW of

Frisco City, Monroe County, Alabama. Section described

in Glawe, 1969» P. 94 (Byram Marl, Glendon Ls., Marianna

Ls.).

Byram Marl: Sample 5 By 01, 1 foot above base.

Glendon Ls.: Sample 5 G-l 01, 4 feet above base; Sample

5 G1 02, 10 feet above base.

Marianna Ls.: Sample 5 Ma 01, 35 feet above base.

Location 6-3. Road cut and stream banks along County road 1

adjacent to Thompson*s Mill Creek, 1.6 miles SW of Perdue

Hill, Monroe County, Alabama. Section described in Cooke,

1926, p. 282 (Marianna Ls., Red Bluff Clay, Shubuta Clay).

Marianna Ls.: Sample 6 Ma 01, 3 feet above base.

Red Bluff Clay: Sample 6 RB 01, 11 feet above base.

Location 7-5. Claiborne Bluffs along U.S. 84 at Alabama

River, Monroe County, Alabama. Section described in Miss.

Geol. Society guidebook, 9th field trip, 1952, p. 60

(Cocoa Sand, North Twistwood Creek Clay, Moodys Branch

Marl, Gosport Sand).

Gosport Sand: Sample 7 Go 01, 2 feet below top.

Location 8-2*. Road cut on U.S. 43, 6.8 miles N of U.W. 84-

U.S. 43 S intersection in Grove Hill, Clarke County, Ala

bama. Seotion described in Miss. Geol. Sooiety guidebook, 135 9th field trip, 1952, p. 65 (Yazoo Clay, Moodys Marl,

Gosport Sand).

Location 9-1*. Road outs near County road 50, S of Magnolia,

Marengo County, Alabama. Section described (Stop 4) in

Miss. Geol. Society guidebook, 15th field trip, I960,

p. 24 (Nanafalia Pm.).

Location 10-3*. Road out, County road 14, 4.2 miles W of

Gilbertown, Choctaw County, Alabama (Yazoo Clay, Moodys

. Marl, Gosport Sand),

Location 11-3*. Road cut, State road 17, 4.3 miles S of

Gilbertown, Choctaw County, Alabama. Section described

in Miss. Geol. Society guidebook, 9th field trip, 1952

p. 70 (Lisbon Fm., Tallahatta Fm.).

Location 12-1*. Road cut on U.S. 84 at Whatley, 5.2 miles E

of U.S. 84-U.S. 435 Intersection in Grove Hill, Clarke

County, Alabama (Shubuta Clay).

Location 13-6*. Road cuts on U.S. 84, 9.9 miles E of U.S.

84-U.S. 435 junction in Grove Hill, Clarke County, Alabama

(Red Bluff Clay, Shubuta Clay, Pachuta Marl).

Location 14-1. Road cuts and cliff exposures, County road 15,

5-6 miles S of Jackson, Clarke County, Alabama. Section

described in Toulmln, 1962, p. 33 (Glendon Ls., Marianna Ls.)

Marianna Ls.: Sample 14 Ma 01, 8-10 feet below top.

Location 15A-1. Road cut, State road 10, 0.6 mile NW of But

ler, Choctaw County, Alabama. Section described in Miss.

Geol. Society guidebook, 10th field trip, 1953, p. 44

(Bashi Marl).

Bashi Marl: Sample 15A Ba 01, from boulder zone. 136

Looation 15-2*. Road out, County road 15, 6.1 miles S of

Jaokson, Clarke County, Alabama. Seotlon desorlbed In

Toulmln, 1962, p. 34 (Salt Mtn. Ls. and other unltB).

Location 16-21. Little Stave Creek, 3 miles N of Jackson,

1 mile W of U.S. 43, Clarke County, Alabama. Section

described In Russell, 1955, p. 457-458 (Marianna Ls.,

"Mint Springs Marl,” Red Bluff Clay, Shubuta Clay, Yazoo

Clay, Moodys Marl, Gosport Sand, Lisbon Fm., Tallahatta

Fm.).

Marianna Ls.: Sample 16 Ma 01, 1-2 feet above base;

Sample 16 Ma 02, 5 feet above base; Sample 16 Ma 03, 8-9

feet above base.

Mint Springs Marl: Sample 16 MS 01, 2 feet above base;

Sample 16 MS 02, 1 foot below top; Sample 16 MS 03, 6 feet

above base.

Red Bluff Clay: Sample 16 RB 01, 1 foot above base; Sample

16 RB 02, 4 feet above base; Sample 16 RB 03, 1 foot from

top.

Gosport Sand: Sample 16 Go 01, 3 feet above shark tooth bed.

Location 17-5. Road cuts on County roads 35 and 29, 1.5 to

2.5 miles S of Suggesvllle, Clarke County, Alabama, Sec

tion described in Glawe, 1969, P. 94 (Glendon Ls., Marianna

Ls., Red Bluff Fm.).

Marianna Ls.: Sample 17 Ma 01, 5 feet below top; Sample

17 Ma 02, 7 feet below top; Sample 17 Ma 03, 11 feet below

top; Sample 17 Ma 04, 20 feet above base.

Red Bluff Clay: Sample 17 RB 01, approximately 5 feet from

top. 137 Location 18-15. St. Stephens quarry, Lone Star Cement Co.

at St. Stephens Bluff on Tombigbee River, 2 miles NE of

St. Stephens, Washington County, Alabama. Section de

scribed in Glawe, 1969, p. 92 (Chickasawhay Ls., Bucatunna

Clay, Byram Marl, Glendon Ls., Marianna Ls., Forest Hill

Sand, Red Bluff Clay, Shubuta Clay, Pachuta Marl).

Byram Marl: Sample 18 By 01, 1 foot above base.

Glendon Ls.: Sample 18 G1 01, 1.5 feet below top.

Marianna Ls.: Sample 18 Ma 01, 9 feet above base; Sample

18 Ma 02, 13 feet above base; Sample 18 Ma 04, 18 feet

above base; Sample 18 Ma 05, 35 feet above base.

Red Bluff Clay: Sample 18 RB 01, 1.5 feet above base;

Sample 18 RB 02, 3 feet above base; Sample 18 RB 03, 7

feet above base; Sample 18 RB 04, 9 feet above base; Sample

18 RB 05, 12 feet above base.

Location 19-3. Road cut on U.S. 84 (Waynesboro, Miss, to

Silas, Alabama highway) 0.5 miles E of Bucatunna Creek,

Wayne County, Mississippi. Section described in Glawe,

1969, P. 91 (Marianna Ls., Mint Spring Marl).

Marianna Ls.: Sample 19 Ma 01, 3 feet above base; Sample

19 Ma 02, 10 feet above base.

Location 20-4. Old State Prison quarry on Limestone Creek,

200-300 yards above confluence with Chiokasawhay River,

3 miles N of Waynesboro, Wayne County, Mississippi. Sec

tion described in Miss. Geol. Society guidebook, 6th field

trip, 1948, p. 34 and 65 (Byram Marl, Glendon Ls., Marianna

Ls.). 138

Marianna Ls.: Sample 20 Ma 01, 7 feet below top; Sample

20 Ma 02, 1 foot below top; Sample 20 Ma 03, 16 feet below

top; Sample 20 Ma 04, 25 feet below top.

Location 21-3*. Shubuta Hill, gully on left bank of Chicka

sawhay River Just N of river bridge at Shubuta, Clarke

County, Mississippi. Section described in Miss. Geol.

Society guidebook, 6th field trip, 1948, p. 32 (Red Bluff

Clay, Shubuta Clay, Paohuta Marl).

Location 22-2*. Road cut on State route 15, 0.1 mile S of

Interstate 20 at Newton, Newton County, Mississippi (Cook

Mtn. Fm., Potterchitto Member).

Location 23-1. Road cut on County road 528, 1.4 miles SE of

Heidelberg, Jasper County, Mississippi. Section described

in Glawe, 1969, p. 91 (Glendon Ls., Marianna Ls.).

Glendon Ls.: Sample 23 G1 01, 3 feet above base.

Location 24-5. Smith County Lime quarry, Just east of West

Tallahala Creek on State road 18, 2 miles E of Sylvarena,

Smith County, Mississippi. Section described in Glawe

1969, p. 90 (Bucatunna Clay, Byram Marl, Glendon Ls.,

Marianna Ls., Mint Spring Marl).

Glendon Ls.: Sample 24 G1 01, 4 feet below top.

Marianna Ls.: Sample 24 Ma 01, 10-12 feet below top;

Sample 24 Ma 02, 2-3 feet below top.

Location 25-3*. Riverside Park, 0.5 miles E of U.S. 51 N,

Jackson, Hinds County, Mississippi. Section described in

Miss. Geol. Society guidebook, 9th field trip, 1952, p. 86

(Cockfield Fm., Moodys Branch Marl). Location 26-5. Marquette Cement Co. quarry, 2 miles SW of

Brandon, Rankin County, Mississippi. Section described

in Miss. Geol. Society guidebook, 15th field trip, I960,

p. 12 (Byram Marl, Glendon Ls., Mint Spring Marl).

Glendon Ls.: Sample 26 01 01, 2 feet above base.

Location 27-4*. Mint Spring Bayou, U.S. 61 N near north

gate of National Military Cemetery, Vicksburg, Warren

County, Mississippi. Section described in Miss. Geol.

Society guidebook, 6th field trip, 194-8, p. 22 (Glendon

Ls., Mint Spring Marl, Forest Hill Sand).

Location 28-2*. Road cut, U.S. 61 N, 3.2 miles N of Vicks

burg, Warren County, Mississippi. Section described in

Cheetham and Glawe, 1964, p. 4, Stop 3 (Byram Marl,

Glendon Ls.).

Location 29-4*. Mississippi Valley Portland Cement quarry,

State road 3, 3 miles N of Junction with U.S. 61 at Red

wood, Warren County, Mississippi. Section described in

Cheetham and Glawe, 1964, p. 5 (Byram Marl, Glendon Ls.,

Mint Spring Marl).

Location 30-5*. Road cut on U.S. 61 N at Vicksburg Bypass,

7 miles N of Vicksburg, Warren County, Mississippi. Sec

tion described in Cheetham and Glawe, 1964, p. 5» Opt.

Stop A (Glendon Ls., Mint Spring Marl).

Location 31-5. Mississippi River bluffs (left bank), 300

yards N of bridge at Vioksburg, Warren County, Mississippi.

Section described in Cheetham and Glawe, 1964, p. 3 (Glen

don Ls., Mint Spring Marl). 140

Glendon Ls.: Sample 31 G1 02, 1 foot above ledge 2

as described.

Location 32-1. Rosefield Cemetery, State road 126, approxi

mately 0.1 mile E of cemetery in abandoned railroad cut

at Rosefield, Catahoula Parish, Louisiana. Section de

scribed In Chawner, 1936, p. 100 (Rosefield Marl beds).

Rosefield Marl: Sample 32Ro 01, bed 15 of Chawner.

Location 33-2*. Montgomery Landing, left bank Red River at

Montgomery, Natchitoches Parish, Louisiana (Moodys Marl).

Supplementary Locations

Location A-l. Road cut on Georgia highway 147, 2.2 miles

N of Pulaski County line, Houston County, Georgia.

Cooper Marl: Sample A Co 01.

Location B-l. River banks near and 200 yards N of McGowin

Bridge on right bank of Conecuh River, Escambia County,

Alabama. Section described in Glawe, 1969, P. 96 (Byram

Marl, Glendon Ls.).

Glendon Ls.: Sample B G1 01, 8 feet below top.

Location C-l. Banks of small stream 3 miles SW of Monroeville,

Monroe County, Alabama. Section described in Ivey, 1957,

p. 87 (Byram Marl, Marianna Ls.),

Marianna Ls.: Sample C Ma 01, 2 feet from top.

Location D-l. Road cut on County road 6, E of Murder Creek,

0.5 mile E of Castleberry, Conecuh County, Alabama. Sec

tion desoribed in Glawe, 1969, P. 95 (Byram-Bucatunna,

Glendon Ls.).

Byram Marl: Sample D By 01, 6 feet from top. Location E-l. Hiwannee bluff along cut bank on east side of

Chlckasawhay River about 1 mile SW of Hiwannee, Wayne

County, Mississippi. Section described In Miss. Geol,

Society guidebook, 6th field trip, 1948, Stop 9, P. 33.

(Red Bluff Clay, Yazoo Clay).

Red Bluff Clay: Sample E RB 01, 6 feet from top.

Location F-l. Byram type locality, 0.3 miles E of old Byram

at bridge on right bank of Pearl River, Hinds County,

Mississippi. Section described In Monroe, 1954, p. 87

(Byram Marl).

Byram Marl: F By 01, 8 feet from top.

Location G-l. Bayou Toro, Sabine Parish, Louisiana (Danville

Landing Beds).

Danville Beds: Sample G Da 01.

Smithsonian Samples

Location Sl-5. Little Stave Creek, Alabama. See Location 16.

Lisbon Formation: Sample SI LI 01, 15 feet below top.

Gosport Formation: Sample SI Go 01, lower part of unit;

Sample SI Go 02, upper part of unit.

Shubuta Clay: Sample SI Sh 01, 5-6 feet below top.

Moodys Marl: Sample 31 MB 01, Just below Perlarchus lvelll

beds.

Location S2-1. St. Stephens Quarry, Alabama. See Location 18.

Shubuta Clay: Sample S2 Sh 01, 5-6 feet below top.

Location S3-1. Road cut 0.6 mile W of Butler, Alabama. See

Looation 15.

Bashl Fm.: Sample S3 Ba 01, in marl boulders at base. Location S4-1. Claiborne Bluffs, Alabama. See Location 7.

Moodys Marls Sample S4 MB 01, In lower P. lvelll bed.

Location S5-1. Outcrop S of Belhaven College, Jackson, Hinds

County Mississippi.

Moodys Marl: Sample S5 MB 01.

Location S6-1. Sam Smith*s quarry, Florida. See Location 1.

Bumpnose Ls.: Sample S6 BU 01, 6 feet above base.

Location S7-3. Surface exposures and core holes, Jackson

County, Florida. Locations described in Cheetham, 1963,

p. 85 (Bumpnose Ls., Crystal River Ls.).

Bumpnose Ls.: Sample S7 Bu 01, from Spondvlus dumpsus

zone (Sample FJ-15 of Cheetham).

Crystal River Ls.: Sample S7 CR 01, Florldlna antlqua

zone (Sample FJ-9 of Cheetham); Sample S7 Cr 02 (Sample

FJ-17 of Cheetham). INITIAL DATA MATRIX

Sampling Units

1 2 0 1 0 1 0 1 2 1 1 1 1 1 1 1 1 1

2 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0

3 2 1 2 1 2 1 1 1 1 1 1 1 1 1 1 1 1

4 0 0 0 2 2 0 0 0 0 1 1 0 1 0 1 1 1

3 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0

6 1 0 1 1 1 0 0 0 0 0 0 1 0 0 0 0 1

7 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0

8 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 0 0

9 1 1 0 0 0 1 1 1 0 1 1 1 1 1 1 1 1

10 0 0 0 0 0 1 0 2 2 1 1 1 1 2 2 1 1

11 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 1

12 0 2 2 2 1 2 0 0 2 1 1 1 2 1 1 2 1

13 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1

14 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1

15 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1 1

16 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0

17 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0

18 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0

19 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

20 0 3 2 2 2 3 3 3 3 3 3 3 3 3 3 3 3

21 1 1 1 1 1 0 0 1 0 0 0 0 0 0 0 1 1

22 0 0 1 0 0 1 1 1 1 1 1 1 1 2 2 2 1 144

Sampling Units

23 1 1 1 0 1 2 9 1 1 1 1 1 1 1 1 1 1

24 . 0 0 0 0 0 0 0 0 0 1 1 1 1 9 1 1 1

25 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0

26 1 1 1 1 1 1 9 0 1 1 0 1 1 1 1 1 1

27 0 2 1 0 2 0 1 1 2 2 1 2 2 2 2 2 2

28 1 1 1 1 9 0 9 9 0 0 0 0 0 9 0 0 0

29 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0

30 0 0 0 0 0 1 9 1 1 1 1 1 1 1 1 1 1

31 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0

32 1 0 0 0 0 0 0 0 1 0 0 0 0 9 1 1 0

33 1 1 0 0 0 0 0 0 1 1 0 1 0 9 0 1 9

34 0 0 1 1 1 0 1 0 0 0 0 0 0 9 0 0 9

35 0 1 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1

36 2 0 0 0 0 1 9 2 2 2 2 2 2 1 2 2 2

37 1 0 0 0 0 2 9 2 2 2 2 2 2 2 2 2 2

38 2 0 0 0 0 2 9 1 2 2 2 2 2 2 2 2 2

39 2 0 0 0 0 3 9 2 2 2 2 2 2 1 2 2 2

40 1 0 0 0 0 2 9 1 2 2 2 2 2 2 2 2 2

41 1 0 0 0 0 2 9 2 2 1 2 2 1 2 2 2 1

42 2 0 0 0 0 2 9 1 3 3 2 3 2 3 2 3 3

43 1 0 0 0 0 1 9 2 1 2 2 2 2 1 2 2 1

44 1 0 0 0 0 2 9 2 2 2 1 1 1 2 2 2 1 145

Sampling Units

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

2 0 0 0 0 0 0 0 0 1 0 2 0 1 2 2 0

3 1 1 1 1 1 1 1 0 0 0 1 1 1 2 2 1

4 1 1 0 0 1 0 0 0 0 1 1 0 2 2 2 0

5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

6 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0

7 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

8 0 0 0 0 1 0 0 0 0 0 0 0 1 1 1 0

9 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1

10 2 1 1 1 1 2 2 1 1 1 1 2 1 0 0 1

11 0 0 0 0 0 0 0 1 0 0 1 0 0 2 2 0

12 2 1 1 1 2 2 1 1 1 1 2 2 2 2 2 1

13 1 1 1 1 1 1 1 1 1 0 1 0 0 0 0 0

14 0 0 0 0 0 1 0 1 0 0 0 0 1 1 1 0

15 0 0 0 0 0 0 0 0 1 0 1 0 0 1 1 0

16 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0

17 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

18 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0

19 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

20 3 3 3 3 3 3 3 3 3 3 3 2 3 3 3 3

21 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

22 1 2 1 1 1 2 1 1 2 1 2 1 1 0 0 1 146

Sampling Units CVJ (C) 17 18 19 20 21 22 24 25 26 27 28 29 30 31 32

23 1 1 1 1 1 1 1 1 2 1 1 1 1 0 0 1

24 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1

25 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0

26 1 0 0 0 0 0 0 0 0 0 1 0 1 0 1 0

27 2 2 2 2 2 2 2 2 2 1 2 2 1 0 0 2

28 0 0 0 1 1 0 0 1 1 2 1 1 1 1 1 1

29 0 0 0 0 0 0 0 0 0 9 0 0 0 1 1 0

30 1 1 1 1 1 1 1 1 1 0 1 0 1 0 0 1

31 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

32 0 1 0 0 0 1 0 0 0 0 0 0 0 0 0 0

33 0 0 9 0 0 0 0 0 0 0 0 0 0 0 0 0

34 0 0 9 0 0 0 0 0 1 9 0 1 0 0 0 0

35 1 1 1 1 1 1 1 1 1 9 1 1 1 1 1 1

36 2 2 2 2 2 2 2 2 2 1 2 2 2 0 0 1

37 2 2 2 3 2 2 2 3 2 9 3 2 2 0 0 1

38 1 2 1 2 2 1 2 3 3 9 2 2 2 0 0 2

39 2 2 2 2 2 3 2 2 2 9 2 2 2 0 0 1

40 2 2 2 2 2 2 2 2 2 9 2 2 2 0 0 2

41 2 2 1 1 1 2 2 2 2 9 2 2 2 0 0 1

42 2 2 2 2 2 2 3 3 2 9 2 3 3 0 0 3

43 1 1 1 1 1 1 1 1 1 9 1 2 1 0 0 1

44 2 1 1 1 1 1 1 1 2 9 1 1 1 0 0 1 PLATES 148

PLATE I

Adeonellopsls magnlporosa

Figure 1. Frontal view of specimen 1 showing depressed asoopore area and large ascopores, x 25. Bashl Marl, Choctaw County, Alabama,

Figure 2. Frontal view of same specimen with distinct ascopores, well developed total area rim, and prominent suboral avicularium, x 50.

Figure 3. Interior view of same specimen showing primary orifice, multiple, rounded ascopores and marginal areolae, x 50.

Figure 4. Portion of a zoarlum, specimen 2, showing much occlusion on older generation zooecia and sev eral non-ocoluded individuals along the distal and lateral margins, x 25. Bashi Marl, Choctaw County, Alabama. PLATE I 150

PLATE II

Adeonellopsls magnlporosa

Figure 1. Frontal view of specimen 3 showing secondary orifice, suboral avicularlum, thick total area rim, several ascopores and somewhat indistinct areolae, x 50. Bashi Marl, Choctaw County, Alabama.

Figure 2. Frontal view of same specimen with ascopore area little visible, x 100.

Figure 3. Frontal view of specimen 4 with numerous zooecia and two larger, marginal gonoeoia with a little depressed ascopore region, x 50. Bashi Marl, Choctaw County, Alabama.

Figure 4. Portion of the same specimen showing prominent ascopores and suboral avicularia, x 100. PLATE II 152

PLATE III

Adeonellopsls transversa

Figure 1. Frontal view of specimen 1, a zoarial fragment with small, rhombic zooecla, transverse suboral avicularium and small asoopore area, x 25, Gosport Sand, Monroe County, Alabama.

Figure 2. Frontal view of same specimen showing large secondary orifice, marginal areolae and lateral tubercles, x 50.

Figure 3. Frontal view of same specimen, "single” ascopore apparent but overlies cribrate area, x 100.

Figure 4. Frontal view of specimen 2 showing more occluded zooecia proximally, some with proximal avicularla, x 25. Lisbon Formation, Clarke County, Alabama.

Figure 5. Frontal view of specimen 3 with prominent proxi mal tubercles, large secondary orifice and trans verse suboral avicularium, x 50. Moodys Marl, Hinds County, Mississippi.

Figure 6. View of colony basal region, specimen 4, showing occluded zooecia and reticulate surface, oral region distinct in some cases, x 50. Gosport Sand, Clarke County, Alabama.

Figure 7. Portion of a zoarium, specimen 5> with occluded and nearly occluded zooecia, x 25. Gosport Sand, Monroe County, Alabama. PLATE III 154

PLATE IV

Adeonellopsls qulsenberryae

Figure 1 Portion of a zoarium, specimen 1, showing thicker basal area with occluded zooecia, x 12. Gosport Sand, Clarke County, Alabama.

Figure 2 Frontal view of specimen 2 showing well developed zooecia with prominent distally directed suboral avicularia, x 25. Gosport Sand, Monroe County, Alabama.

Figure 3 Frontal view of same specimen showing medially constricted total area rim and stellate asco pores, x 50.

Figure 4 Frontal view of same specimen with marginal areolae encirollng zooecia, x 100.

Figure 5 Frontal view of specimen 3 showing an early stage of occlusion. Many suboral avicularia are cov ered and proximal avicularia are evident. Secon dary orifice is more rounded, x 50. Gosport Sand, Clarke County, Alabama.

Figure 6 Frontal view of specimen 4 showing advanced oc clusion, oral area retains identity, x 50. Gosport Sand, Monroe County, Alabama.

Figure 7 Frontal view of specimen 5 showing complete oc clusion in basal region, scattered avicularia present, x 50. Gosport Sand, Monroe County, Alabama.

Figure 8 Interior view of same specimen showing primary orifice, ascopores and areolae. Thick frontal wall is evident along right margin of colony, x 25. PLATE IV 156

PLATE V

Adeonellopsls cyclops X

Figure 1. Portion of zoarium, specimen 1, subcyclindrioal base with occluded Individuals, x 12. Cooper Marl, Houston County, Georgia.

Figure 2. Frontal view of holotype showing many small zooecia and several larger swollen gonoecia. Marginal zooecia longer with indistinct ascopore area, x 25. Cooper Marl, Houston County, Georgia.

Figure 3. View of same specimen showing total area rim, secondary orifice, ascopore area and suboral avicularia. Gonoecia with distinct ascopore region and distal avicularium, x 50.

Figure 4. View of same specimen showing detail of frontal surface, x 100.

Figure 5. Frontal view of paratype 1 with numerous zooecia, x 25. Cooper Marl, Houston County, Georgia.

Figure 6. Frontal view of same specimen with noticeable areolae and upward projecting round suboral avicularium, x 50.

Figure 7. Frontal view of paratype 2. Gonoecium at upper left. Ascopore area, suboral avicularia, secon dary orifloe, areolae distinct, scattered lateral and proximal avicularia present, x 50. Cooper Marl, Houston County, Georgia. PLATE V 158

PLATE VI

Adeonellopsls oyolops ovolops

Figure 1. Frontal view of specimen 1 showing several zooecia with rounded suboral avicularium, distinct ascopores and proxlmally tapering total area rim, x 50. Red Bluff Clay, Clarke County, Alabama.

Figure 2. Frontal view of same specimen. Secondary ori fice with moderate distal hood. Avicularia, ascopore, and areolae distinct, x 100.

Figure 3. Frontal view of specimen 2 showing longer mar ginal zooecia with weak frontal differentiation, several central zooecia and numerous swollen gonoecia, x 25. Red Bluff Clay, Monroe County, Alabama.

Figure 4. Same specimen with several zooecia at left and larger gonoecia showing wider secondary orifice, round suboral avicularia and large ascopore area with numerous pores, x 50.

Figure 5. Same specimen showing several broad gonoecia with well-developed, semi-stellate pores, x 100.

Figure 6. Fragment of zoarium, specimen 3, with narrow, compressed laminae, basal zooecia occluded, x 12. Marianna Limestone, Monroe County, Alabama. PLATE VI

5 6 160

PLATE VII

Adeonellopsla oyolops cvcIopb

Figure 1. Frontal view of specimen 4 showing young zooecia with prominent secondary orifice and suboral avicularia but little other frontal differentia tion, x 50. Marianna Limestone, Washington County, Alabama.

Figure 2. Frontal view of specimen 5 showing older more occluded zooecia and prominent proximal avicu laria, x 50. Marianna Limestone, Wayne County, Mississippi.

Figure 3. Frontal view of specimen 6 showing zooecia and gonoecia, both with moderate peristome hood, x 25. Red Bluff Clay, Clarke County, Alabama.

Figure 4. Frontal view of same specimen. Secondary ori fice, suboral avicularium, ascopore area and total area rim distinct, small distal avicularium fragment, x 50.

Figure 5. Frontal view of specimen 7 showing considerable occlusion, but oral region distinct and proximal avicularia common, x 50. Mint Spring Marl, Clarke County, Alabama.

Figure 6. Frontal view of specimen 8 with well-developed, rounded, suboral avicularia, distinct ascopore region, marginal areolae and proxlmally taper ing total area rim. Moderate peristome hood present, x 50. Red Bluff Clay, Clarke County, Alabama.

Figure 7. Frontal view of same specimen. Suboral avicu larium occupies essentially all of proximal part of secondary orifice, x 100. PLATE VII

6 7 162

PLATE VIII

Adeonellopsls galeata

Figure 1. Frontal view of specimen 1 showing zooecia and wider gonoecia with larger ascopore area, x 25. Glendon Limestone, Monroe County, Alabama.

Figure 2. Frontal view of same specimen. Suboral avicu laria, proximal avicularia, secondary orifice and distal peristome hood prominent. Broad gonoecia have a large ascopore area with numerous pores, x 50.

Figure 3. Frontal view of same specimen showing thick total area rim, proximal avicularia and distinct mar ginal areolae, x 100.

Figure 4. Part of a zoarium, specimen 2, branches bifoliate, moderately compressed, x 12. Byram Marl, Conecuh Co un ty, Alabama. PLATE VIII

3 4 164

PLATE IX

Adeonellopsls galeata

Figure 1. Frontal view of specimen 3* Several zooecla at right, several gonoecia in center area. Areolae, proximal avicularia, ascopore region, total area rim and secondary orifice distinct, x 50. Glendon Formation, Washington County, Alabama.

Figure 2. Frontal view of basal area of same specimen showing more occlusion but many frontal structures still distinct additional avicularia on proximal and distal margins noticeable, x 50.

Figure 3. Frontal view of specimen 4 showing numerous zooecia with sharp and distinct peristome hood. Secondary orifice, suboral avicularia, small ascopore area prominent, x 50. Glendon Forma tion, Jasper County, Mississippi.

Figure 4. Interior view of specimen 5, showing elongate zooecia, primary orifice and multiple ascopores, x 50. Byram Marl, Conecuh County, Alabama. PLATE IX VITA

Noland Embry Fields, Jr. was born September 26, 1933 in Memphis, Tennessee, the son of Noland Embry and Miriam

Wells Fields. He attended the public schools of Tennessee and Alabama. In 1951, he entered the University of Tennessee where he received the B.A. degree in 1955. After serving two years as an officer with the United States Seventh Army, Ger many, he re-entered the University of Tennessee as a graduate student in geology. He was awarded the M.S. degree in I960.

In 1962, after working in private industry for two years, he accepted a position as an instructor in geology at

Western Kentucky University. He entered the Graduate School of Louisiana State University in 1965 with a National Aero nautics and Space Administration fellowship to begin doctoral study in paleontology and geology. In 1967, he returned to

Western Kentucky University where he is currently assistant professor of geology. He is a candidate for the Ph.D. degree in the School of Geosciences, Louisiana State University at the December, 1971 commencement. EXAMINATION AND THESIS REPORT

Candidate: Noland Embry Fields, Jr.

Major Field: Geology (Paleontology)

Title of Thesis: The Bryozoan Adeonellopsis in the Paleogene of the Southeastern United States

Approved:

Major Professor and Chairman Comu

ean of the Graduate School

EXAMINING COMMITTEE:

.0 . _/ ■

Date of Examination:

November 2 9, 1971