TWO NEW CRINOIDS FROM LOWER MISSISSIPPIAN ROCKS IN SOUTHEASTERN KENTUCKY
BY
GEORGE M. EHLERS AND ROBERT V. KESLING
Reprinted from JOURNAL OF PALEONTOLOGY Val. 37, No. 5, September, 1963 JOURNALOF PALEONTOLOGY,V. 37, NO. 5, P. 1028-1041, PLS. 133,134, 3 TEXT-FIGS., SEPTEMBER,1963
TWO NEW CRINOIDS FROM L20\'C7ERMISSISSIPPIAN ROCKS IN SOUTHEASTERN KENTUCKY
GEORGE M. EHLERS AKD ROBERT V. ICESLING Museum of Paleontology, The University of Michigan
.~BsTR.~~T-AII~~~~specimens collected many years ago bl- the senior author and his students near Mill Springs, Kentucky, are a new species of Agaricocrinzis and a new speries of Actino- crinites. Although only one specimen of each is known, it is well preserved. The new Agnrico- crinus bears a resemblance to A. ponderoszts Wood, and the new Actinocriniles to four species described by Miller & Gurley: A. spergenensis, A. botuztosz~s,A. gibsoni, and A. shnronensis. A preliminary survey of species assigned to Agaricocrinz~ssuggests that revision of the genus is overdue. Although the occurrence of the specimens leaves some doubt as to their stratigraphic posi- tion, we conclude that they both probably weathered from the Fort Payne formation and rolled down the slope onto the New Providence, where they were found. The sites where the crinoids were picked up are now deeply inundated by water impounded by the Wolf Creek dam on the Cumberland River.
INTRODUCTION onto the New Providence, \$here they were OTH of the new crinoids described here are found. rZt present, both the New Providence B from Lower Mississippian rocks in the valley formation and the I~asalbeds of the Fort Payne of the Cumberland River in Wayne and Russell are underwater at the type locality of the new Counties, Kentucky. They were among numer- Acti~zocrinites. Because parts of the area are no ous fossils collected by the senior author and his longer accessible for collecting, we feel that the students in the 19201s, when the University of description of the new species should not be Michigan conducted its summer field course in delayed any longer, despite the lack of additional geology from Mill Springs, Kentucky. We believe material. these were picked up in 1926. The sites from which the two crinoids were OCCURRENCE obtained has since been inundated by Lake To explain the occurrence of the two crinoids, Cumberland, created when the water of the it is necessary to present a brief summary of the Cumberland River was impounded behind Wolf stratigraphy along this part of the Cumberland Creek dam. As explained below, there is reason to River valley. In 1926, the following formations believe that the specimens weathered from the were exposed in beds of tributary streams, valley Fort Payne formation, and rolled down the slope walls, and nearby uplands (see text-fig. 1): Thickness RiIississippian system (feet) Ste. Genevieve limestone-light gray, oolitic and finegrained limestone layers, fossiliferous...... St. Louis limestone--bluish to gray, finegrained to lithographic limestone, 20-foot coarsely crystal- line layer at top, fossiliferous...... Warsaw formation-massive, dark gray to bluish-gray, argillaceous to coarsely crystalline lime- stone; bluish-gray laminated chert layers near base; 20-foot gray, thin beddcd Somerset shale unit about 60 feet above base; fossiliferous...... Fort Payne formation-gray, coarsely crystalline, and argillaceous limestone with numerous chert layers and geodes; %foot gray shale bed about 25 feet above the base, fossiliferous...... New Providence formation Upper rnember-greenish-gray, soft, laminated calcareous shale, weathering to sticky- clay... some fossils ...... Beaver Creek oil "sand" member-rather massively bedded impure limestone, cavernous or porous where yielding oil, fossiliferous with crinoid colurnnals...... Lower member-like upper member, fossils scarce; black to dark gray phosphate nodules at base Chattanooga shale-black shale weathering to gray...... Silurian system Brassfield limestone-gray to brown, massive dolomitic limestone, arenaceous to sandy, weathers to light reddish-gray, fossiliferous with many fluted cystoid colurnnals...... 8-15 Ordovician system Richmond formation-greenish to brownish-gray, interbedded nodular argillaceous limestone and shale layers, bedding thinner and more even in lower half; lower half unfossiliferous, upper half with few fossils ...... 45-50 CRIMOIDS FRO-If LOTITER ,JfISSISSIPPIA N ROCKS, KENT L7CK Y 1029
El SSte. Genevieve
i; ~orsorsow a a Fort Payne L? Nevi Providence - [Gnpl 1Chattanooga
-J ~1 Brassfield
FAULT
& CUMBERLAND SCHOOL
FC - Forbush Creek 0 8 - Dry Branch GC - Cub Creek BL - Bee Lick Creek
A TEXT-FIG.I-Geologic map of a small area northwest of Mill Springs, Icentucky, measuring four miles on each side. Area includes parts of Pulaski County (northeast corner), Russell County (northwest corner), and Wayne County (so~~thernpart). The encircled dot represents the site where the specimen of Agaricocrinus podagriczrs, n. sp., was picked up. The Cumberland River and its trib~itariesare shown as they were in 1926. At present, Lake Cumberland covers most of the New Providence and all the older formations. Compiled from field map of the senior author, suppleiuented by structure map of Knapp & Twinem (1933, map 51).
Nearby, the Middle Silurian Crab Orchard As for Klepser's statement, quoted by Stockdale formation, interbedded greenish shale and green- (1939, p. 55), that south\\-ard from central ish-gray to buH limestone, rests disconformably Kentucky the Chattanooga shale may be as on the Brassfield. young as St. Louis, we believe that Weller et al. Incidentally, the stratigraphic assignment of (1948, p. 165) properly judged it as "untenable" the strata here included in the upper member of because of the presence of fossils of "IVarsal~, the Wen- Providence formation has been ques- Osagean, and possibly Kinderhookian" age in tioned. In his unpublished doctor's thesis (1937), strata above it. Klepser called the Ion-er and Beal-er Creek rnem- As could be seen before the damming of the hers the "Forbush Creek facies" of the Xelv Cumberland River, erosion of the soft lower and Pro\-idence. This n-as later endorsed by Stock- upper members of the Nem Pro~idenceforma- dale (1939, p. 77). Inasmuch as the strata super- tion produced steep esposures below the ledges jacent to the Beaver Creek member are by of the resistant Beal-er Creek member and the lithology, fauna, and age allied to the underl>-ing Fort Pa)-ne formation. On many of the small beds and not to the OX-erljingFort Pal-ne, we tributaries of the Cumberland Rix-er, the soft can see no reason to remo\-e them from the New shales of the Nenr Pro\-idence 11-ere undercut so Pro\-idence formation. Therefore, our interpreta- that the basal Fort Payne chert beds and the tion of stratigraphy follon s that of Butts (1922) Beaver Creek hard limestone capped TI-aterfalls. rather than Klepser (1937) and Stockdale (1939). bIany of these exposures are now belo\\- the sur- 1030 GEORGE M. EHLERS AND ROBERT V. KESLING
cz -
Species PIOI.. in D.,S;I cup !: a, 1; o21. rn uWPar2 -.me. Awl F~~ula~ 1 "8 8 :; 1 podogricus 315 1 I4 < 1" w, ve~1" ( K 14.3.2 23 1" I obol;;Ion I/1 ; 1, 1 "0.1 314 1 rnedlum convexus (Hall) 1860 ~rofundus orge, > 3. m 1 pity I obou" 1 H~W 1 X 14-22 2 I ponderosus ? / wrioble I modem" height Wood 1909 1 lbOe1 38 1 m d 1 ; o 1 i/ coorsely gionulose nodosus t 1 21(2l 1 2 l/2 x RR 1'"~ I$!%. 1 2/3i?l I
rnonfgorneryensir Peck 8 Keyte 1938 1 bu//ofus 1 smooth depressed / B 12.2-2 Holl 1858 1 pyramidal crossus smoolh, slightly Clherby 881 1 fuberosus (Troost) 1849 I =Onvex grocilis smooth or finely qron- Meek 8 Worthen I861 1 ~~~~~~o~ffiu~~~el~n~~ plonoconvexus flat, smooth / E,C (2-2-2 Hall 1861 bloiri 1 9 1 qhti> R s lY1 b 1 1 < 1" 1 ~:d;$ 1 C i-l-! i?l sfellolur 1 $ar, 12, "'1 &out I 1 $610 1 hem~spher~col plote~ (Hall) 1858 bei~o~rernus 1 smooth, S~OIIOW 1 24") 1 )I% ser, 1 2 1 :,12 to 1 35 h19h 1 B 2-2.2 iHoll1 1861 infiotus smooth 1 24 ~n1 ~WX aa 1 sa,, I 2 1 12 1 ;; 1 h:gh as wide I B 12-2-2 iHoIl1 1861
orculus qh1 I K lj2.2 lhan 1 Hsubcon8col sornpson~ 1 14 I medium, - RR 1 sar, I P 1 4/5 IVZ I 'bpporently short" ( c 12-2-2 Miller 1894 (
face of Lake Cumberland. IVolf Creek, and other places in the area. At various places along and near the banks of On the other hand, there is no assurance that , the river, the senior author and his students at the new species of Agaricocri7zus came from the the University of Michigan summer camp during Fort Payne formation. Butts (1922, p. 56) listed the 1920's found crinoid specimens loose on the "Agavicocrirzz~sundes. sp. Burlington type" from ., slopes of the loner member of the New Provi- the Beal-er Creek member of the New Provi- dence. Among the species a-ere illlopvosc~llocrinzis dence in a road exposure 1%miles southeast of colzicus Casseday & Lyon and the tm-o new Parnell, Wayne County (about 9 miles south- species described here. Alloprosnlloc~i~zushas west of the site where our specimen of Agarico- only been found in place in rocks of Keokuk age. crizus \\-as picked up). \Ye are unable to under- In Tennessee and southern Kentuclry, A. coniczis stand what Butts meant by "Burlington type" occurs in the Fort Payne chertj limestone. Its and we cannot locate his specimen or specimens. presence on the slope of Ken. Providence soft Butts also reported (1922, p. 52,55) Agarico- shale strongly suggests that at least some of the crinzis sp. from the New Providence shale at crinoids weathered out and rolled don-n the Ken\\-ood Hill and Buttonmold Knob (5 and 12 slope from Fort Payne outcrops. Certainly, this miles south of Louisville) and hIeshack Creek could have been the situation at the Forbush (about 10 miles east of Tompkinsville). Bassler Sr Creek locality (text-fig. I), near the mouth of Moodey (1943) record no Agaricocrinus species CRISOIDS FRO?.( LOT,VER aT~fISSISSIPPI.-lAT ROCKS, KENT UCK I' 103 1
- ---- I 3. -E urn I g 5 Species 1.5 ,n ;.,.-I ;UP LN, RR Lfv4 .*, .;-en c,' 2 Br8 J:gE2 B 1 1 :z pyromidofus srnoolh 1 5 2 1 , bo 1 SBq 1 2 1 1 . 1 ~HoIl~l858 I to 1 ~4.1JX~;;&?!,~ 1 8 12.2.2 proecursor 1 ei 1 I I 1 I t 1 a, j 2 I about I 1 2/5 1 h~rn!spher~col j F 12-2-2 Rowley 1902 I 172'r RR elegons Welherby 1881 1 K,K 13(41-2-2 fiscellur 1 pa' I 2(g OI~OSI I I ~3ig 1 ;:pn,p (Hall) 1861 hemlspherrcol conicus 1897 geometricus / I8 1/2 1 ohout = RR j PB~, 1 2 I c I 1 I 1 hern~sphericol (Hail) 1859 /ouis;onensis + 1 I 1 loI, b 1 8 I 1 ? 3l4 1 If3 1 H = 2/3 St 0, Rowley 1900 1 - RZ(21 less brevis 1 is,, 1 2 ) >I I %or I COI x wider 1n.n 12-2-2 (Hall) 1858 hlgX dorsal CUP ond iegnien ai = hetght 1 excovolus pyram~dol o !ittle
(Hal 11 1861 ;zg;2h PBr? 32 ;&Ib/y long^, g% of yo; 1 rider thdn high 1 1 1 1 1 1f2 other ' 1 / 1 splendens 1 22 "2 1 = 0, c RR 1 P 2 1 l(g 1 5>2 I0 1 ~~p~~~e~, Miller 8 Gurley 1890 pyromldol coreyi 1 smooth, convex 1 30 oobt 1,1 2 1 if4 1 2f5 1 docso! cup rother (Lyon 8 Cossedoy) high far genus 1860 wh~tfieldi / 34 112 I :k;dby,"'r I PBr, I ;fgie;yote c I 1 315 Holl 1858 obout : 'RR I KsK I 2-2-2 worfheni smooth, knobs on PBrBrZ depressed Hall 1858 43 :m:!1'21' "" %,:yy pyrom~dol 1 1 I I I I 1 I K,K I 2-2-2 hodgsoni strongly sculptured 1 26 I "':R,a,f3 1 S& 2,very 1 c 1 1 <1/2 1 H: 2i3 W Mliier 8 G~rley 896 norrow 1 on6 long I 8 I 3-2-2 odomsensis H= obaut 2/3 W, I B 13-2-2
~- icwensis SBr and Tar slrongiy 1 23 1 I but 1 Par 1 2 0 i 1 ""t 1 1 8 j; $ghtiy > 1 K /413i3-2 Mler 8 iurley 837 1 yfloted 1 ncd~Icsus 1 ;&pP ,;$ndmd~ng 32ID 1 oboul = RR a 1 2 I 1 1 1 b"odl~~~omid"I K,K lqa-q"-i Worthen 1889 c keokukensis Sar ond Tar strongly 1 33 1 :mi;, abcut 1 par2 1 I or 2 1 about 1 1 1~2 Y;~,",";;;~ 213 W, / K 13(4)-4(31.2 Mlller 8 Gurley 1897 / 'nf'o'ed I *K=Ft.Poyne K=Keokuk B=Burlin~ton FZFernGlen C=Chouteau smooth lhrough PBr and inner hoii tar. PBr very inilated ond outer ends of IBr strongly convex r All RR hove strond centrol ridge-llke'kode 02nd the mterrohiots ore otmost wort-llke:' 4 011 Plales below orm regions thickened, rising above suture l~nesin nodose or tuberculous extensions, especially lBr, 7 dorsal cup depressed saucer-shaped, ventrol disc irregular hemispheric, bulging at posterior side U Formuio represented by sequence of orrns In L or RPosI. L or RAnt, and Ant
from the New Providence, but they list 12 "distinctly New Providence forms" (Butts, species from the Fort Payne (see tables 1 and 2 1922, p. 82). herein). \Tie do not knou- the source of the two crinoids Butts described an occurrence of crinoids very described here. Studies by Butts (1922, p. 50) similar to that of ours. On Roaring River, Over- and others indicates that the Nev- Providence ton County, Tennessee, he (1922, p. 82) col- formation is older than Keokuk and probably , lected, among other crinoids, Allo~/osallocri~zz~sdoes not contain beds younger than the lo~ver conicz~sand Agaricocri~zztsamericc~izz~s from the Burlington. The Fort Fayne is generally cor- "slope on the shale and limestone, of the New related lsith the Keokuk. Our ne\v species of Pro\-idence." Because he regarded Alloprosallo- Agaricocrinzls is definitely more closely related to crilzz~sconicz~s and ilgaricocri~zzlsnnzerica?zz~s as Iceokuk species than to Burlington. Further- guide fossils of Keolcuk strata, Butts concluded more, the specimens of illlop/osallocri~zusco?zi- that the examples of these species had rolled cus, dgc~ricocril~uspodegricus, n. sp., and Acti7zo- do\\-n the slope from the "heavy basal limestone crilzites tripus, n. sp., seem to be presened in the of the Fort Pa)-ne," which at that locality es- same manner. Hence, although the possibility of tended to the top of the clifi. -1s identified b>-1Ir. their occurrence in the Xen- Providence cannot Frank Springer, howex-er, the crinoid fauna also be ruled out, we are inclined to think that they included Cattillocri)z~~stemtesseeae Shumard and reathered out of the Fort Payne and rolled Ste?nmatocril~z~strazrtscholdi ~&Ii~achsmuthSr do~~-nthe slope to the places where they \\-ere Springer, both of which Springer decided 15-ere found. GEORGE Al. EHLERS AND ROBERT V. KESLING
SYSTEhlhTIC DESCRIPTIOSS especially those based on one or two specimens, Subclass CAMERATAWachsmuth & the known calices are immature. Nevertheless, Springer 1885 A. stellatzrs seems to be very small and A. Order A'IOSOBATRRAMoore & Laudon 1943 worthelzi very large. During the geologic range of In describing the t\vo nem camerate crinoids, Agaricocrinz~s, species appear to have evolved we elect to follow the terminology, suprageneric toward larger size. taxa, and classification used by Moore & Laudon (3) The form of IBrBrl. The species are listed (1943). in both table 1 and table 2 by decreasing relative length of IBrBrl. For most species, the size of an Family DESMIDOCRINIDAEAngelin 1878 IBrl is compared xith that of the average for the Genus AGARICOCRIKUSHall 1858 RR. Thus, the IBrl is 3 to 4 times the size of one \TTithout reviewing the regrettable handling of R in A. bellatrenzus, but it is only 4 to 5 times the the Troost manuscript (Wood, 1909, p. 1-3), we size of an R in A. kodgso~zi. aclinowledge James Hall as the legal author of (4) The most distal plates of the dorsal cup in the genus (as did Bassler & Moodey, 1943, p. contact with IBrBrl. This characteristic ex- 284). presses the relation of bordering plates to The adequately substantiated species of IBrBrl, as nell as the length of IBrBrl. The Agaricocrinus are compared in tables 1 and 2. distal plate does not always accord xvith the rela- The data were compiled mostly from published tive length of IBrBrl. For example, the IBrBrl descriptions and illustrations, supplemented for in A. gracilis are relatively long but they do not a few species 11-ith observations of specimens in project beyond PBrBrl, whereas the IBrBrl in the Museum of Paleontology of the University A. lzodgso~zi (=A. adamsensis) are relatively of Michigan. short but they extend as far as SBrBrl or SBrBr2. For most species Itre accept the synonymy (5) The number of IBrBrz. Our terminology given by Bassler & Moodey (1943), but me of plates may at first appear confused, inasmuch regard A. geometricus, described by Hall in 1859 as those plates which lie beyond IBrBrl in A. (p. 56), as a distinct species rather than a junior po7zderosus, A. convexus, A. podagriczrs, and a synonym of A. stellatz~sHall 1858. The tabular few other species are definitely on the tegminal comparisons emphasize the strong similarities side of the calyx. Nevertheless, these plates are between certain species. We are convinced that homologous with those beyond IBrBrl in A. Agaricocrinus adamsensis Miller & Gurley lzodgsoni ( =A. adamsensis) , A. iowensis, and 1896b is a junior synonym of A. hodgsoni Miller other species, which are confined to the dorsal & Gurley 1896a, and that A. keokukensis Miller side of the calyx. Hence we feel justified in & Gurley 1897 is a junior synonym of A. nodulo- referring to any plates immediately beyond szrs \&'orthen 1889. Other species show close IBrBrl as the IBrBrz, regardless of their position resemblances, presumably because of close rela- on the calyx. Only two species have three tionships. IBrBrz in each interradius: A. ponderosus and In table 1, the species are compared with our new species, A. podagricus. 111 each inter- respect to the folloving: (1) The ornamentation radius in most species, the two IBrBrz are about and convexity of the plates in the dorsal cup. In equal, but in one or more interradii in a few spe- some species, such as A. stellatz~s and A. geo- cies, the plates do not share the interradius metricus, the plates are granulose; in others, such equally, so that one IBrz is broad and the other as A. americanzs, they are finely granulose; in narrow; in extreme instances, one plate displaces + A. lzodgs01zi (=A. adanzse~tsis) the plates are the other entirely in the proximal part of their strongly sculptured, particularly the RR; many extent. are smooth; and some have different kinds of (6) The length/xvidth ratio of the RR. In only 4 ornamentation on the various parts of the cup. one species, A. illinoise~zsis,is the length of each Plates of the dorsal cup also vary according to R significantly greater than its width. In a few, cons-exity: in some species, all plates are strongly such as A. iz~berosz~s,A. bellatremz~s,and A. in- convex; in some, all are slightly convex; in others $atus, the length of each R is only half its width. all are smooth; and in few, typified by A. iowen- In the majority of species, the length and n-idth sis and A. ~zodz~losus(=A. keokz~kensis),the of RR are equal. The ratio does not appear to be central plates are smooth but the SBrEr and correlated with any other characteristic of the TBrBr are strongly convex. calyx. (2) The minimum diameter of the calyx meas- (7) The length/width ratio of the PBfB.12. As ured through the PostL-PostR interradii. This with the ratio of length/n-idth of the RR, that of measurement is listed only as a general indica- the PBrBrz is independent of other character- tion of the size of calices that have been de- istics. The maximum ratio is about 1, in A. scribed. We do not doubt that for many species, profundus, A. tuberoszrs, and A. wizilfieldi; the CRIiVOIDS FRO31 LOTVER i1IISSISSIPPIAN ROCKS, KENTUCKY 1033
1 Rotio of rneowrement/PbstL-PpitR diomstsr I
podogricus ...... A6 .I2 .83 1.53 convexus ...... A1 .24 1.07 1.26 profundus ...... 1.381 .I7 ...... 80 1.21 ponderosus ...... 1.371 .I4 .89 1.47 nodosus ...... 36 .20 .95 1.52 tuguriinus ...... (.35) .24 ...... 1.07 1.17 i//inoisenris ...... (.34) .21 1.97 1.32 ottenuotus ...... 34 .I8 .I3 1.73 omericonus ...... 33 .20 ...... 1.05 1.35 montgomeryensis .33 .I7 1.28 1.39 bullotus ...... 32 .I8 ,913 1.32 crossus ...... 1.32) .16 ...... 1.16 1.43 tuberorus ...... 31 .I0 .78 1.53 grocilis ...... 1.291 .18 1.08 1.21 lon no convex us ...... 29 .I7 ...... 94 1.37 bloiri ...... 29 .I6 1.00 1.32 stellotus ...... 27 .I9 1.15 1.39 bellotremus ...... 27 .23 ...... 1.12 1.29 inflotus ...... 27 .I8 .78 1.15 orcu/us ...... 27 .I 7 .85 1.08 sompsoni ...... 26 .I9 ...... 1.04 1.61 pyromidotus ...... 26 .I9 .92 1.23 proecursor ...... 26 .21 .89 1.20 elegons ...... 26 .I5 ...... 1.06 1.59 fiscellus ...... 24 .24 1.20 1.24 conicus ...... 1.241 (.I61 1.921 (1.28) geometricus ...... 24 .I7 ...... 1.18 ? louisionensis ...... 23 .I3 .96 1.23 brevis ...... 22 .I9 .97 1.19 excovotus ...... 20 .I 1 ...... 67 1.22 splendens ...... 18 .I3 .78 1.22 coreyi ...... I .22 .93 1.17 whitfieldi ...... I6 .10 ...... 67 1.33 worthen; ...... I4 .I0 .91 1.37 hodgsoni ...... I3 .IS .77 1.12 odomsensis...... I2 .I 7 ...... 76 1.14 ~owens~s...... I2 .I4 .58 1.52 nodulosus ...... 12 .12 .54 1.29 keokukensis ...... I I .12 .49 1.30 " K=Ft. Poyne K=Keokuk B=Burlington F=Fern Glen
minimum is less than a, in A. illi~zoise~zsis,-4. visions of Lov-er LIississippian formations. How- ' anzericanzis, A. Elairi, A,i?z$atzls, A. p~aecz~rsor, ever, the oldest species are those listed from the A. fiscellzis, and others. Chouteau (C) ; for the 11lost part, those recorded (8) The shape of the tegmen. This feature de- from Fern Glen (F) and Burlington (B) are in- serves low priority as a specific character, be- termediate in age; and those from I TEXT-FIG.2-Aga~ico~~inzrs podagricus, n. sp. Diagram of plates labeled with conventional symbols. Outline of calyx as seen in basalview is indicated by dotted lines in IBrBr areas. Based on holotype. lengths of IBrBrl. In one group, characterized known specimen. Calyx preserved only to arm by A. iowensis, A. nodtrlosus, and A. hodgsoni, bases. Calyx relatively Ion-; as vien-ed posteriorly the IBrBrl became short and subcircular; in the its width nearly 24 times its height (pl. 133, fig. other, characterized by A. polzderosz~sand our 1). Tegmen gently convex and dorsal cup rather new species, A. podagricz~s, the IBrBrl became strongly concave; hence, central part of calyx exceptionally elongate, extending around the thin. As seen in basal vie]\- (pl. 133, fig. 5), calyx sides of the calyx into the tegminal area, ac- unequally pentalobate, with left-posterior and companied by concomitant displacement of the right-posterior rays (LPost and RPost) very IBrBr2. Not all Agaricocrinz~sbecame special- large and expanded distally, left-anterior and ized; certain of the Keokuk species retained the right-anterior rays (LAnf and RAnt) medium and primitive 2-2-2 arm development. Another trend very slightly expanded, and anterior ray (Aitt) is the increase in size (see table 1). Of the species small and tapering. Anal area wide, but other which attained a PostL-PostR interradial diam- interbrachial areas relatively very narrow and eter in excess of 35 mm. all are Iceokuk in age; U-shaped (pl. 133, figs, 4,5). Each ray of the , and of those exceeding 25 mm. in this diameter, cup somex~hatinflated beyond PBYI,so that the one is pre-Burlington, three are Burlington, and calyx placed on a level surface rests upon 14 are Keokuk. Insofar as we knoli-, only one SBrBrl and TBrBri. LPost and RPost free at dgaricocrirlzrs species having the combination of TBrBrz and beyond; LAlzt and mint free poste- long PBrBr, and 4-3-2 arm pattern has been riorly at TBrBr? and anteriorly at SBrBra and reported in pre-Keokuk strata; this exception is beyond; and A~ttfree at SBrBrz or SBrBra. A. anzericalzus, n-hich has been listed from Upper BB rather large for the genus, apparently ex- Burlington strata in hIissouri as well as from tending beyond the impression of the columnal, Keokuk beds in Tennessee, Kentucky, LIissouri, together forming a hexagon slightly larger than Iowa, and other states. one of the RR (text-fig. 2; pl. 133, fig. 5). RR and X forming an in~erse,truncated, lon- pyra- LA~.~~~~~~~~s~~PODAGRICUS, n. sp. mid, the surface of each plate nearly flat. ,%rite- PI. 133, figs. 1-6; text-fig. 2 rior R (4.0 mm. \vide) smaller than other RR Description.-Based on holotype, the only (each 4.8 mm. TI-ide). Length/\\-idth ratio of each GEORGE .If. EHLERS ,41VD ROBERT V. KESLIh7G R about 2. Each R hexagonal, its two proximal than those on the inner. TBrBy alternating along sides more than twice as long as its t\so distal the midline of the half-ray. Three or four TBrBr sides. in each rox, graduated in decreasing length X slightly larger than any R, a little longer distally. TBrBrz and distal plates extending than wide. Each of the three XXI large, extend- around free edge of the ray base onto tegininal ing around the edge of the cup onto the tegminal side of the ray. side of the calyx, its greatest width about equal In each uniserial half-ray, SBrBri succeeded to that of X (text-fig. 2). Central XI an elongate by three or four additional SBrBr, graduated in hexagon with very long proximal sides. Each slightly decreasing length distally. In LAnt and lateral XI tapering distally, bordered by X2, the RAd, the SBrBr alternating some\\ hat irregu- central XI, X, R, PBrl, PBr2,SBrl, TBrl, TBr?, larly with the TBrBr of thc posterior half-ray. In and one or two small tegminal plates, hence hav- Aut, the SBrBr of the t\vo sides alternating ing 10 or 11 sides. XX? consisting of three plates regularly. SBrBrs or SBrBrz and distal plates spread fan-wise around the end of the central extending around free edge of the ray base onto X1 and between the ends of the lateral XXI; tegininal side of the ra>-. central X? shorter than lateral XX2, surn~ounted Each IBrl exceptionally long and narrow by three small plates (XX3?)to form a subdued (text-fig. 2), curved around edge of dorsal cup anal bulge (pl. 133, fig. 1). onto tegmen (pl. 133, figs. 3-6). Each IBrl proxi- , PBrBrl quadrangular, only slightly narron7er mally acuminate (its end inserted bet~veentwo than adjacent RR, each with length/width ratio RR), expanded distally to attain greatest width about g. PBrBrl pentagonal with short proximal between PBrBrz, constricted at periphery of the sides, each about as vide or slightly n-ider than cup, enlarged slightly on tegminal side of calyx, the corresponding R and covering an equal area, tapered betxeen lateral 1BrB1.2, and truncated its length/width ratio about 3. PBrBrl and by middle IBr2. Length/\vidth ratio about 2.6. PBrBr2 in LPost and RPost slightly larger than Greatest width of IBrl about 2 that of an adja- those in LAlzt, RAnt, and Ant. Each PBrBrg cent PBrl. In postero-left and postero-right aaillary. interrays (PostL and PostR), IBTIbordered by SBrBrl relatively large; those in LPost and 15 plates: 2 RR, 2 PBrBrl, 2 PBrBr?,2 SBrBrl, 2 RPost and in the posterior hal~~esof LAnt and TBrBrl, 2 TBrBr2, and 3 IBrBrz, In antero-left RAnt axillary, pentagonal, slightly larger than and antero-right interrays (AdLand A?ztR),IBrl PBrBrz; those in anterior halves of LAnt and bordered by 14 plates: 2 RR, 2 PBrBrl, 2 RAnt and A?zt subtrapezoidal, about the same PBrBrz,2 SBrBrl, 2 SBrBrz, 1 SBr3 (on posterior size as adjacent PBrBm. Hence, of the plates side), and 3 IBrBrz. Three IBrBr2 above each distal to SBrBrl, those in LPost and RPost bi- IBrl, about equal in size, each much longer than serial in both half-rays; those in LAnt and RAlzt wide. biserial in the posterior half-ray and uniserial in Plates of the dorsal cup smooth and well pre- the anterior half-ray; and those in Ant uniserial served as far out as PBrBrl, corroded in distal in both half-rays (text-fig. 2). In other words, parts of rays, with the surface layer gone from each symmetrical half of the dorsal cup with its some plates (pl. 133, fig. 5). Rough surface of three posterior half-rays biserial and its two SBrBr and TBrBr probably the result of corro- anterior half-rays uniserial. sion rather than original tuberculate ornament. In each biserial half-ray, the dichotomy on Specimen mostly silicified; hence, some of the SBrBrl asymmetrical, with the TBrBr on the rough surface likely due to differences in preser- outer side of the ray distinctly xider and shorter vation. Posterior region smooth. EXPLATATIOKOF PLATE133 All figures X 12 Frcs. I-6-Agaricocrinz~s fiodagricus, n. sp. Stereograms of holotype, UhIXIP KO.44456, in Post, RPost, PostR, tegrninal, basal, and Ant views. JOURSAI, OF YALTOSTOLOGY. 1 OL. 2 ' YLATIS 133 Ehlcrb CY hc5111ig Tegrnen lo\\, nith 7 nodose plates in the mid- each interray. In addition to the number of dle, 11 nodose plates near the margin, and rela- IBrBr?, A. podagricz!~and A. potzderosrrs share ti\ el! smooth plates in the interambulacral sex-era1 other characteristics in common: sixteen areas (pl. 133, fig. 4). Posterior oral bearing the arms disposed according to formula 4-3-2, long largest node, central. farming the ientral apes, IBrBri, rather broad posterior interra), large slightly larger than the combined BB below. areas of the rays extending bel.ond the interrays. Node on each of the other four orals about half smooth basal concayit)-, nodose oral and "radial as large, not cox-ering all the surface of the plate, dome" plates on the tegmen, interrays extending situated abo~ethe junctions of RR in the dorsal beyond tips of PBrBr?, and slight convexity of cup. Sma!l node separated from the orals on a the distal plates (beyond SBrBrl) in the dorsal so-called "radial dome" plate of each posterior cup. .4. podagriczrs differs from A. po?zderoszrs, ambulacrum, overl~ingthe R/PBrl junction in ho\ve\.er, in having narrolver IBrBrl, Ion-er teg- the cup. Large nodes (nearly as large as that on men. and more broadly<. exuanded rays. Further- the posterior oral) on so-called "radial dome" more, in the distal parts of the rays ;beyond the 1 plates near the tegminal margin, placed above interi-ening PostL), the adjacent edges of LPost the corresponding SBrBrl of the cup: three in a and LAnt form a very small angle in A. podagri- cluster over LPost and RPost, two over LAnt and GZLS, hereas the corresponding edges form nearly RAvt, and one over Ant. Of the nodes over LPost a right angle in A. porzderoszrs. (In each species, and RPost, the tn-o dorsal placed side-by-side of course, this angle is duplicated on the opposite with a ridge leading from each to the junction of side of the calyx, between the edges of RPost and the t~voarms in the half-ray, and the third cen- RAwt n-here they project beyond PostR.) Simi- tered ventral and proximal atop them. Of the larly, beyond the intervening AntL, the adjacent nodes over LAnt and R:l~zt,the dorsal situated edges of Lilnt and Ant form a noticeably smaller above the biserial half-ray with a ridge leading to angle in A. podegricz~sthan in A. ponderosus (as the junction of the two arms in the half-ray, and do the adjacent edges of RAnt and Ant beyond the second situated ventral, proximal, and ante- A7ztR). rior to the first, inore or less above the middle of The name of this species is derived from the the uniserial half-ray. The single node over Ant Greek adjective ao6ayp~~os("gouty"), and refers centered above the ray with a ridge leading to the fancied resemblance of the expanded dorsally to the junction of the two arms. Sur- LPost and RPost (text-fig. 2; pl. 133, fig. 4) to faces of all nodes rough, like those of SBrBr and afflicted legs. TBrBr, probably not original1~-tuberculate. Locality.-Slope exposure about $ mile from 'Anal bulge subdued. Area between anus and the illouth of Forbush Creek, in \;Ciayne County, posterior oral plate crushed, not \\re11 preserved. Kentucky (see text-fig. I), approximately 4f Entry of each ambulacrum into teg~nenex- miles northwest of Mill Springs and 9% miles pressed as a vertically elongate, deep indentation north of RiIonticello; about 500 feet south of ventral to the thick arm bases (pl. 133, figs. Forl3ush Creek and 1000 feet east of Cumberland 1-4,6). Details of arms and stem unkno\irn. River, at an elevation of about 657 feet MSL (in Remarks.-As can be noted in Tables 1 and 2, 1926 about 76 feet above the Cumberland River, the new species can be readily distinguished from now about 66 feet below the surface of Lake all other species of Agaricocrinzrs except A. potz- Cumberland). deroszis by its three (instead of t\vo) IBrBr2 i11 1ialotype.-UMMP No. 44456. All figures X2 FIGS.I-6-Actinocrinites tripus, n. sp. Stereograms of holotype, UMIIP So. 41157, in tegminal, Post, basal, PostL, Ant, and LAnt views. TEXT-FIG.3-Actinocri~zites tripz~s,n. sp. Expanded diagram of plates of dorsal cup labeled with conveniio~~al symbols. BR are shown in lateral view. Boundary of IBrBr and IAv~bA77l.bareas indistinguishable. Xodose plates of tegrnen not shown. Based on holotype. Family ACTIXOCRISITIDAEBassler 1938 R-RPost R-B junctions; and sruall indentations, ACTISOCRISITESTRIPUS, n. sp. one on each half of the LPost R/B and RPost PI. 134, figs. 1-6; text-fig. 3 R/B sutures. Ant B with small, deep, round pits Description.-As viewed basally, calyx penta- at corner junctions with LAnt R and RAnt R; lobate nith quadrate extensions of the rays and shallower pits at the LAzt R-Ant R-B and RAlzt deep IBrBr indentations between arm bases; as R-Ant R-B junctions; and two smaller deep pits, 3iexved laterally, truncated obpyrarnidal except one on each half of the Ant RIB suture. Impres- for flaring base, sides relati\,ely flat abole RR sion of column circular, less than half the diarne- and X, tegmen convex and covered with sub- ter of the BB. spherical nodes. RR equal, each slightly more than half the size BB equal, by far the largest plates of the of a B, distinctly broader than high. Each R with calyx, broad, thick, flaring out and don n, form- a large, laterally expanded, central spine; as seen ing a substantial base on n hich the calyx rests basally, spines of RR projecting beyond edges of when placed upright (pl. 134, figs. 4-6). As BB (pi. 134, fig. 3). LPost and RPost RR each liewed basally, BB forming a subcircular trifoli- hexagonal, bounded by B below, X and R at the ate ring (pl. 134, fig. 3). As viewed laterally, each sides, PBrl above, and by IBrl and XI at the B subquadrate, except for the some\vhat taper- upper corners; each with fairly strong ridges ing upper (ventral) third, with rounded distal sloping from the large spine to the centers of the corners (text-fig. 3; pl. 134, fig. 5). Each B nith sutures n-ith B, R, X, and PBrl, lon-er ridges to striae perpendicular to the distal edge and curv- the centers of the sutures with XI and IBrl, and ing around edge from lateral onto basal side, tv.0 small, narron- ridges slanting do\r-n to the there becoming radial (pl. 134, figs. 3,s). BB suture with B, one near each corner (along the located Inore or less in RPost, LPost, and i-llzt sides of the shallo\\-pits at the R-R-B and R-X-B positions. LPost and RPost BB nith small, deep, junctions); hence, each R ornamented by eight round pits at corner junctions nith LAnt R, X, ridges radiating from the -\.crli prominent central and R~llltR; shallo\\ er pits at the LAnt R-LPost spine, \\-it11 the vertical and horizontal ridges R-B, LPost R-X-B, KPost R-X-B, and RAnt larger than the others. Aizt R also hexagonal, bounded by B belu\\-, r\\-0 IiK at the sides. PBrl (pl. 131. fig. 2). :'is vie\\-ed basally, S and the five ahox-e,and t\\-o IBri at the uoner. , corners: radiat- RIi outlining a hexagon L>- their lateral ridges, ing riclgc-5 similar in size and arrangelnerlt to \vith the central spines farming protuberant. those in LPost and RPost RK (1~1. 131. fig. 5). rounded apices (pl. 135, fig. 3). L--!?I! and K.li!t liR each septagonal. I~ounded11y SSl tn-o eclual plates, each hexago~~al,about + t\\-o BB I)elo\v. t\vo RK at the sides. PBrl abo\.e. as large as X. Each XI n-ith a shallo\\-, subtri- and t\vo IBrSr, at the upper corners; each R angular depression or pit at each corner, giving it \\-ith sex.tn ridges sloping oui: from the central a stellate pattern of ridges; ridges confined to the spine. those to the centers of the sutures n-ith the rnargiaal area, proximally confluent ~vithcentrai ti\-u RB, t\i-~adjacent RR, and PBrl larger and Bat area of the plate, distally aligned I\-ith ridges more clear]>-defined than those to the sutures of adjacent plates. Each XI bounded by the I\-ith the t\vo IBrBr, (111. 131. fig. 6); the t~oother XI, S, R, PBrl, and t\r-o XX? (text-fig. 3; ridges to the BB set astride the circular pit at the pl. 131. fig. 2). B-R-B junction. SX? three subequal plates, hexagonal or 1 PBrBrl equal, each slightly more than half the septagonal. Shallo\\-,subtriangular depressions at size of the adjacent R, its \:idth more than 1; the lo\\-er corners and veq- shallo\v, less distinct times its height. Each PBrl bearing a strong depressions at the upper corners producing a , x-ertical ridge continuous n-ith ridges on the R fluted or scalloped appearance around the mar- belo\\- and YBr2 above. Suljtriangular pits at gin of each XP. XX3 and succeeding ro\vs of each corner, producing a subordinate radial plates in the anal series more nulnerous and ornamentation of Ion- ridges. LPost and RPost irregular in size and shape. So expressed bound- PBrBrl I~oundedb)- R belo\\-, XI, X?, IBrl, and ary bet~veenplates of the dorsal cup and those of IBr? at the sides, and PBr2above; other PBrBrl the tegmen in the Post interradius (pl. 134, each hounded b>-R, two IBrBrl, ti\-o IBrBr?, and fig. 2). PBr?. IBrBrl nearly equal, one in each interradius PBrBr? nearly eclual l~utmore variable than except Post, each hexagonal, approximately PBrBr1, each about 2 the size of the adjacent equilateral, about half the size of an R and about PBrl, distinctl), xvider than high. Each PBrz + the size of a PBrl. Each IBrl with a shallo\v, pentagonal, asillary, hearing a Y-shaped ridge subtriangular depression or pit at each corner, \\-ith branches to the centers of the sr~tureswith giving it a stellate appearance, much like that in PBrl and the t\vo SBrBr1, the sides of the PBr2 the XXI. IBrl bounded by tmo RR below, two sloping rather steeply away from the ridge to PBrBrl at the sides, and tmo IBrBrp above (pl. give the plate a modified-\\.edge shape. LPost 134, figs. 4-6). and RPost PBrBr2each hounded laterally by Xz IBrBrz subec~ual, tn-o in each interradius and IBrz, other PBrBrz each I~oundedlaterally except Post, each hesagonal or septagonal, about by t\\-o IBrBr2. the same size as an X?.Shallo\v, subtriangular SBrBrl varj-ing in size, each approximately f depressions at the loiver corners. About four the size of the PBrzon which it rests, pentagonal, IBrBr3in each interradius, irregular. Succeeding n-ider than high. Each SBrl with a central ridge IBrBr plates s~llalland irregular. No expressed from n-hich the sides slope stecp1)- a\\-a)-, making boundary bet\\-een dorsal cup and teg~nenin any the plate a-edge-shaped. Each SBrl adjacent to interradius (pl. 134, figs. 4-6). the SBrl in the other half of the ray, with the Tegmen convex as vie\\-ed laterally (pl. 134, - sloping inner sides of the t\\-o SBrBrl forming a figs. 2,4-6). IBmbd4rnb deep troughs floored \I-ith 1'-shaped trough along the rniddle of the ray. small, irregular, sr~loothplates. .Anal extension X a little smaller than one of the RR, hexag- round, offset to\\-ard Post, about seven plates in , onal, bounded bj- t\vo BB belo\\-, t\vo RR at the the circlet at the base; base about as wide as X; sides, and t\i-o XX, aho1.e. Plate ornamented length of extension unkno\\-n (pl. 13-2, fig. 1). with a large, late]-ally expanded, central spine, Anzbilmb areas 01-erlain bl- plates with large, much like those on the RR, from which promi- corltiguous or nearlj. contiguous, finely papillose, nent ridges slope to the centers of the sutures subspherical nodes arranged in five radiating n-ith each of the Ijordering p!ates. Each corner of bands, one in each Anzb, each band t\vo to three X depressed: at the lo\\-er (dorsal) corner, a nodes in \\-idth. small, deep, circular pit at the B-X-B junction; Zir~nsunknon-n. Insofar as can Ile judged from at each lo\\-er lateral corner, a shallo\ver, sub- the axillary SBrBrl, each ray \\.it11 four arms. triangular pit at the B-.Y-R junction; and at each Surfaces for attachment of arms \-erticallj. elon- of the thrce upper (x-entral) corners, a slightly gate, narro\\-, nearly x-ertical on the ends of the larger, shallo\\-, subtriangular pit or depression at rays. To ISBrBr plates; hence the four arms of the XI-X-XI and the t\\-o PBrl-X-.Y1 junctions each ray set side-by-side. 1040 GEORGE -If. EHLBRS LlND XOBERT Tr. KESLING 111 addition to striae on BB and papillae on pl. 2, figs. 10-12j and placed in ilctirzocriizites by tegminal nodes, plates of the calyx ornamented Bassler & IIoodeg- (1943, p. 274). It is I~asedon a nit11 \,cry he, rather indistinct, raised elements crinoid found in the Burlington limestone near some\\ hat irregularly disposed, some apparently Sharon, in south\\-estern 3Iissouri. It I-esem1)les discrete and others in short anastomosing or A. tripus in the shape and relative size of BB and vermiform crests. 0rname:ltation may be in part RIi, the flat sides of the cup, presence of nodes on obscured l,y weathering. RR and X and ridges on PBrUr, and PBrBr?, the Dimensions of holotype: height of calyx, 213 shape of the tegmen in lateral vie\\-, and the mm.; PostL-PostX interradial width, 123 mm.; presence of large nocies in the tegrnen. A. slri~rorl- ~nasimumdiameter of BB circlet, 10 mm. emis can 11e easily separated from A. tripus; it Remarks.-Actii~ocril~ites tripus, n. sp., dicfers has BB nea:-ly vertical instead of flaring, at the from many species of its genus in having large, level of the arms the IBrBr areas al-e only shal- flaring basals, much like those found in species of lo\vly indented, the plates in the lo\\-er (dorsal) Dcrycrinus. There is no need for further compari- part of the cup lack pits or indentations at the son with those species of Actirzocrinites in which corners, and the tegrnen is all covered with no- the BB are small or crossed by ridges. dose plates nith no distinct I.lnzbilnzb areas Four snecies described bv Miller & Gurlev having small, smooth plates. The differences have certain characteristics like those in the new bet~veenthe BB and IBrBr areas of the tno species, and are presumed to be closely related to species are best seen in basal view. it. The first, which bears perhaps the closest The third species bearing certain resemblances resemblance, was described and figured in 1896 to A. tripus was named Actinocrinr~sbolrz~oszcs by (p. 29-30, pl. 2, figs. 4-7) as Steganocrinzcs sper- Miller & Curley (1895, p. 22-24, pl. 2, bgs. 1,2), genensis. Bassler & LIoodey (1943, p. 274) cor- \I ho reported it from the Keokul; formation in rectly transferred it to Acti~zocrinites and gave Tennessee. It is like A. tripus in having large the occurrence as "probably Burlington Is." flaring BB, central spines and radiating ridges on 4. spergenensis (11. & G.) agrees very el ell with RR and X, and nodose plates in the tegrnen In A. tripus in the following characteristics: large, fact, the dorsal cup of A. botrztosz~sas high as the flaring BB; large, laterally expanded, central RR and X can scarcely be distinguished from spines and radiating ridges on RR and X; X that of A. tripzis. Above this lei-el, holvever, the somewhat slllaller than an R; sides of cup rela- resemblance sharply decreases. 1-1.botrzioszts has tively flat; at the level of the arms, the IBrBr central spines and radiating ridges on PBrBrl, and II-lmbAmb areas deep and troughlike; and PBrBr2, XS1, XX2, IBrBrl, IBrBrz, and higher the nodose plates of the tegmen restricted more anal and IBrBr plates. 111 addition, the arm or less to areas overlying the An~bArnb.Further- bases of A. botrz~osztsare not \\-idely separated, more, Miller & Gurley described the plates of the and its IAmbAmb areas contain very few if any cup (p. 29) as "sculptured so as to depress the small, flat plates. angles of the plates," although they failed to The fourth species was named ~IcPinocri~~us show such features in their figures; we suppose gibsoni (R'Iiller & Gurley, 1893, p. 10-11, pl. 2, they \\.ere describing pits or depressions at the fig. 1). It is from Keokuk strata (probably plate corners, such as those reported above in the Edwardsville formation) on Indian Creek, near BB, RR, X, PBrBrl, XXI, IBrBrl, and other Crawfords\~ille,Indiana. The holotype and only plates of A. tripus. Despite these numerous known specimen does not have the Post region similarities, A. sperge?zensisdiffers from A. tripzrs exposed and its tegmen is covered by the arns. . and can be readily distinguished by the follow- It resembles A. tripus in the shape of the BB and ing: as seen basally, the BB circlet is only sliglitly the spines and ridges on the RR.1,ikc "I. botruo- more than half the diameter of the RR circlet; szts, it differs from our species in having central , central nodes and radiating ridges are present on spines and radiating ridges on PBrBr), PBrBrn, PBrHrl; small central spines are indicated oil IBrBrl, I13rB~~,and other plates of the cup. XXI, XX2, and IBrBr plates; the nodose plates '4. gibsol~iant1 A. bolruosz~sal-e \.cry similar; the of the tegrnen are more irregular in size, Ion-er, only difference seems to be that the ornan~enta- and less subspherical than those in A. tripus; and tion of the latter is more strongly developed, the impression of the column is relatively much particularly on the PBrBr and IBrBr plates. larger as compared to the diameter of the BB. In Inasmuch as the species described by 3Filler K: particular, we regard the presence of central Gurley are not nrell represented, it is impossible spines on PBrBrl in A. spergenensis and their to judge whether the specimens are mature. absence in A. tripus as significant and specific Nevertheless, A. spergenerzsis is considerably differences. larger than -2.tripus, with a height of 301 Inm., The second species was named Steganocrirzzts PostL-PostR interradial ~vidthof 20; mm., and sheronensis by Rliller & Gurley (1897, p. 32-33, BB diameter of 133 mm. A. sharorze~~sisis appre- CRIiVOIDS FRO-If LOWER _IfISSISSIPPI,I N ROCKS, KENTGCK IT 1041 ciably smaller, \vith height of 15 mm. and BB ser. 6, v. 7, viiif 188 p., 81 pls., 7 text-figs. diameter of 64 mm. :I.bofrrlosl~s is much larger I-IALI.,JAMI;~, 1859, Contrit)utions to the palaeontol- og>- uf lou-a; bein:: descriptions of new species of than A. triples, n-ith height r~f36 mm. aild BB Crinoidea and ot1ic.r fosils: Geol. Iiept. lo\\-a, diameter of 13 mm. -4. gibsolli is also \.cry large, Suppl. to v. 1, pt. 2, 92 p., 3 pls., unnunibered with BB diameter of 19; mm. \\-e do not belie\-e text-figs. the differences noted above are ontogenetic. I