NATURAL HISTORY OF THE FAMILY

VOL. I

SYSTEMATIC INTERNATIONAL SCHOLARS FORUM

A SERIES OF BOOKS BY AMERICAN SCHOLARS

SCIENCES

1

ADVISORY BOARD

J. ANTON DE HAAS ProfessO'Y of International Relations at Claremont Men's College

PHILIP MUNZ DirectO'Y of Rancho Santa Ana Botanic Garden

WILLIAM T. JONES ProfessO'Y of Philosophy, Pomona College

EDWARD WEISMILLER Professor of English, Pomona College

FREDERICK HARD President of Scripps College

DAVID DAVIES Librarian of the Honnold Library Polemonium eximium on Mount Dana, California. NATURAL HISTORY OF THE PHLOX FAMILY

*

VOLUME 1

SYSTEMATIC BOTANY

by

VERNE GRANT

RANCHO SANTA ANA BOTANIC GARDEN, AND CLAREMONT GRADUATE SCHOOL, CLAREMONT, CALIFORNIA

• Springer Science+Business Media, B.V. 1959 ISBN 978-94-017-5725-6 ISBN 978-94-017-6077-5 (eBook) DOI 10.1007/978-94-017-6077-5

Copyright 1959 by Springer Science+Business Media Dordrecht Originally published by Martinus Nijhojf, The Hague, Nethetlands in 1959 Softcover reprint ofthe hardcover 1st edition 1959

All rights reserved, including the right to translate or to reproduce this book or parts thereof in any form To My Partner ALVA GRANT PREFACE

Believing that it is always best to study some special group, I have, after deliberation, taken up domestic pigeons. Charles Darwin, 1859.

Within the territory of evolution studies ample niches lie open for inquiries projected on a limited scale and centered on a single group of organisms. Com• bined taxonomic, ecological and genetic studies of a single phyletic unit - or family- have made a large contribution to our emerging general theory of evolution. We have recently seen the publication of several such studies. Of particular value are The Evolution of Gossypium by Hutchinson, Silow and Stephens in 1947; Darwin's Finches by Lack, 1947; Babcock's The Genus Crepis, 1947; Manton's Problems of Cytology and Evolution in the Pteri• dophyta, 1950; Simpson's Horses, 1951; the work on the Tarweed Tribe embod• ied in Clausen's Stages in the Evolution of , 1951; Evolution in the Genus Drosophila, by Patterson and Stone in 1952; Goodspeed's The Genus Nicotiana, 1954; and Ford's Moths, 1955. It has been my goal to treat the Phlox family similarly as a model of evo• lution in a group of higher . The family is to pe viewed as a model, not in the abstract sense of. the theoretical and mathematical evolutionist, but rather in the sense of the naturalist - as a complex and far-flung production of nature. Three continents, but primarily western North America, are the physical setting in this model, and :five tribes, eighteen generic lines, and ap• proximately 316 species (most of these highly complex in themselves) comprise the dynamic elements in the system. Before the biological information necessary for an understanding of evo• lution in the Phlox family can be effectively presented, or in some cases even effectively gathered, it is essential to lay the taxonomic groundwork. It is ap• propriate to begin our broad comparative study of the Phlox family with a taxonomic survey. This is followed by chapters dealing with chromosome numbers and karyotype evolution, phylogeny, and phytogeography including migrational history. Research is in progress on a second volume dealing with the reproductive VIII PREFACE biology of the Phlox family and containing separate chapters on the life cycle; pollination; breeding systems; the genetic structure of populations, races and species; fertility relationships; and adaptive radiation in the repro• ductive system. The general plan was to incorporate the descriptive material into the present work and place the experimental findings in the sequel. ACKNOWLEDGMENTS

In the course of preparing the present study I have received help from many colleagues. Dr. Edgar T. Wherry carefully reviewed Chapters 4 and 5 in manu• script, and I have benefitted greatly from his knowledgeable discussions. Mrs·. Alva Grant contributed helpful suggestions concernmg the infrageneric clas• sification of and . Dr. Sherwin Carlquist read Chapters 3 and 7, making a number of important suggestions. Discussions with Drs. Daniel I. Axelrod, Lyman Benson, Jay M. Savage, Barton H. Warnock and Miss Elizabeth Sprague concerning various aspects of Chapter 8 were most profit• able. A discussion with Dr. G. Ledyard Stebbins concerning material in Chapter i was likewise very helpful. Drs. Philip A. Munz, Arthur Cronquist and Edgar T. Wherry helped on many bibliographical questions. I am indebted to Dr. Herbert L. Mason for several points of view expressed in Chapters 3 and 8. Among botanists who have aided in the collection of of in various parts of the world are: A. Beetle (Wyoming and Argentina); D. Dunn (Montana); A. Garaventa (Chile); J. Hunziker (Argentina); H. Johnson (Peru); E. Landolt (Switzerland); P. A. Munz (California); M. Reiche (Peru); M. Ricardi (Chile); J. Rzedowski (Mexico); R. Shaw (Utah); A. Soriano (Argentina); B. Turner (Texas); and Wm. A. Weber (Colorado). The collections contributed by these individuals enabled me to study living plants of a wider variety of Polemoniaceae than would otherwise have been possible. Valuable technical assistance in the cytological phases of the investigation was provided by Mr. Howard Latimer. The geographical localities of certain Polemoniums previously determined for chromosome number were kindly furnished by Drs. C. A. Berger, W. S. Flory, and A. Nygren. Similar data for Phlox were provided by Drs. J. R. Meyer, E. T. Wherry, and 0. E. White. For permission to quote their unpublished chromosome count of gossypijera from the Argentine Andes I am obliged to J. Hunziker and 0. Caso of Buenos Aires. Several of the original figures and copied drawings were prepared by Mr. Stephen Tillett and Mrs. K. Goss. X ACKNOWLEDGMENTS

Permission to use copyrighted illustrations was generously granted by four publishers. Some 18 of the figures in Chapter 4 were reproduced from Illustrated Flora of the Pacific States, vol. iii, by L. Abrams. For making these figures wailable I am particularly indebted to Mrs. Roxana Ferris and the Stanford University Press. Figure 7 is reproduced from Anatomy of the Dicotyledons by C. R. Metcalfe and L. Chalk (Oxford University Press); Figure 23 was redrawn from El Mundo Vegetal de los Andes Peruanos by A. Weberbauer (Ministerio de Agricultura, Lima, Peru); and Figure 72 is taken from The Genus Phlox by E. T. Wherry (Morris Arboretum Monographs, Pennsylvania). The co• operation of the above mentioned publishers is gratefully acknowledged. Many additional figures in Chapter 4 were taken from Die N aturlichen Pjlanzenfamilien and Das Pjlanzenreich (Verl. Wilhelm Engelmann, Leipzig). Figure 27 came from the University of California Publications in Botany, 1950. Individual figures in Chapter 2 were redrawn from a number of journals: American Journal of Botany, 1945, 1946; American Midland Naturalist, 1946; El Aliso, 1950, 1952; Proceedings of the National Institute of Sciences of India, 1940; and Rhodora, 1956. Figure 66 in Chapter 7 was first published in the journal Evolution. Institutional support has been forthcoming from two sources. The Rancho Santa Ana Botanic Garden has supported the research on the Phlox family in every way possible throughout the years. A research grant from the National Science Foundation made possible much of the field and laboratory work incorporated in the new chromosome number records of Chapter 6, and helped in many other ways.

Claremont, California January, 1957 CONTENTS

Preface ..... VII Acknowledgments . IX

1. SYSTEMATIC POSITION OF THE FAMILY 1 Botanical History of the Family 1 Systematic Relationships . . . . 3

2. MORPHOLOGY • • • . • 8 Embryo and Seedling. 9 The Vegetative Body. 13 and Flower 23 The Gametophyte 27 Fruit and Seed ..... 32

3. PROBLEMS OF CLASSIF1CATION 35 Primary Classification . . 36 The Genus Problem. . . . 39 Infrageneric Classification. 43 Minor Systematics . . . 45

4. SYSTEM OF CLASSIFICATION. 48 Synopsis of the Tribes 48 Synopsis of the Genera 52

5. NOMENCLATURE • . • • . • • • • • • • • . . • • 112 Synonymy ...... 113 Alphabetical List of Generic and Infrageneric Names 127 List of Binomials...... 129 XII CONTENTS

6. CHROMOSOME NUMBERS . . . . 161 Materials and Methods . . . 161 List of Chromosome Numbers 163 Karyotype Evolution. 186

7. PHYLOGENY ...... 194 The Primitive Condition 195 Parallelism in Evolution 198 The Influence of Hybridization on Phylogeny 201

8. PHYTOGEOGRAPHY . . . 206 Centers of Distribution 207 Centers of Origin. . . 218 Origin of the Desert Annuals. 224 Pleistocene Relicts . . . . . 228 Disjunct Areas in North America and South America 235

9. GENERAL CONCLUSIONS 249

Classified Bibliography. 262 Index ...... 275 ILLUSTRATIONS

Frontispiece. Polemonium eximium on Mount Dana, California.

CHAPTER 2, MORPHOLOGY Page Fig. 1. Form and position of the embryo in the seed ...... 9 Fig. 2. Early development of the embryo in ...... 10 Fig. 3. Development of the embryo in its older stages in Phlox drummondii. 11 Fig. 4. Cotyledons ...... 12 Fig. 5. Node in Phlox drummondii ...... 14 Fig. 6.~Trichomes ...... 15 Fig. 7. Stem in transverse section...... 16 Fig. 8. of the and Cantua Tribes 17 Fig. 9. Leaves of the Bonplandia Tribe . . . . 18 Fig. 10. Leaves of the Polemonium Tribe ...... 19 Fig. 11. Leaves ofthe Polemonium Tribe (cont.) and Gilia Tribe . 20 Fig. 12. Leaves.ofthe Gilia Tribe (cont.) ...... 21 Fig. 13. Calyx ofGilia tricolor...... 24 Fig. 14. Corolla venation ...... 26 Fig. 15. Embryo-sac development in . . 28 Fig. 16. Tapetum and pollen development in Polemonium caeruleum . 29 Fig. 17. Division of a tapetal nucleus in . 30 Fig. 18. and seeds in ...... 33

CHAPTER 4, CLASSIFICATION

Fig. 19. Cobaea scandens . 53 Fig. 20. Cobaea aschersoniana. 54 Fig. 21. Cobaea pendulifiora . 55 Fig. 22. Cantua quercifolia . . 56 Fig. 23. Huthia coerulea . . . . 57 Fig. 24. Bonplandia geminiflora . 59 Fig. 25. Loeselia pumila . . . . 60 Fig. 26. Polemonium humile . . 64 Fig. 27. . 65 Fig. 28. 66 Fig. 29. Allophyllum divaricatum 67 Fig. 30. Collomia debilis . . . 68 Fig. 31. Collomia heterophylla. 69 Fig. 32. Collomia tinctoria . . 70 Fig. 33. Gymnosteris parvula . 71 Fig. 34. . . . 74 Fig. 35. Phlox nana ...... 75 Fig. 36. and P. austromontana . 76 Fig. 37. gracilis 77 Fig. 38. Gilia rigidula . . 81 Fig. 39. Gilia pinnatifida . 83 Fig. 40. Gilia capitata . 83 Fig. 41. . . . 84 Fig. 42. Gilia leptalea . . 85 Fig. 43. Gilia latifolia . . 86 Fig. 44. Gilia tenerrima . . 87 Fig. 45. 91 Fig. 46. 92 Fig. 47. . 93 Fig. 48. . 94 XIV ILLUSTRATIONS

Fig. 49. Eriastrum densifolium and E. fi.lifolium . 95 Fig. 50. Langloisia matthewsii 96 Fig. 51. . 97 Fig. 52. . . . . 99 Fig. 53. Navarretia eriocephala . . 100 Fig. 54. Navarretia pleiantha . . . 102 Fig. 55. Leptodactylon californicum 103 Fig. 56. nuttallii . . 104 Fig. 57. Linanthus grandiflorus 105 Fig. 58. Linanthus acicularis . 106 Fig. 59. Linanthus aureus. . . 107 Fig. 60. Linanthus dichotomus 110 Fig. 61. Linanthus parryae .. 111

CHAPTER 6, CHROMOSOME NUMBERS Fig. 62. Meiotic chromosomes of representative Polemoniaceae ...... 166 Fig. 63. Dibasic polyploidy in the Gilia leptomeria group ...... 1 72 Fig. 64. Somatic chromosomes of!pomopsis gossypifera ...... 184 Fig. 65. Frequency distribution of basic chromosome numbers in the Phlox family 188

CHAPTER 7, PHYLOGENY Fig. 66. Phylogenetic web of the Leafy-stemmed . . . . . 202 Fig. 67. Two ways by which parallelisms can develop in evolution. 204

CHAPTERS, PHYTOGEOGRAPHY Fig. 68. World distribution of the Polemoniaceae...... • . 208 Fig. 69. Natural areas of the Polemoniaceae in North America...... 212 Fig. 70. Natural areas of the Polemoniaceae on three continents ...... 213 Fig. 71. Composition of the polemoniaceous flora in the different natural areas . . 217 Fig. 72. The present distribution area of the genus Phlox in North America com- pared with the area covered by the latest (Wisconsin) ice sheet. 229 Fig. 73. Distribution ofGilia capillaris in western North America . . . 234 Fig. 74. Trans-tropical distribution patterns in the Polemoniaceae . . 241 Fig. 75. Amphitropical distribution patterns in the Polemonium Tribe. 243 Fig. 76. Amphitropical distribution patterns in the Gilia Tribe . . . . 244 Fig. 77. Amphitropical distribution patterns in the Gilia Tribe (cont.). 245

CHAPTER 9, GENERAL CONCLUSIONS Fig. 78. Evolutionary trends in several morphological characters in the Phlox family ...... 252-256 Fig. 79. Phylogenetic relationships in the Phlox family ...... 258 TABLES Page Table 1. Historical development of a tribal classification of the Polemoniaceae . 4 Table 2. The tropical genera of the Polemoniaceae compared 50 Table 3. The genera of the tribe Polemonieae compared. 62-63 Table 4. The sections of the genus Phlox compared 73 Table 5. The genera of the tribe Gilieae compared . . . 79 Table 6. The sections of the genus Gilia compared. . . 82 Table 7. The sections of the genus Ipomopsis compared 90 Table 8. The sections of the genus Navarretia compared 98 Table 9. The sections of the genus Linanthus compared . . . . 108 Table 10. Basic chromosome numbers of the genera of Polemoniaceae ...... 187 Table 11. Position of the centromere in representative members of the Phlox family 192 Table 12. Richness and endemism of the polemoniaceous flora in different natural areas ...... 210 Table 13. Systematic relationships of the South American herbaceous Polemonia- ceae ...... 242 Table 14. The parallel development in different families of genera fitted for the environmental conditions in four subcontinental regions ...... 260