BIOLOGY 1 9 ::?9 The person charging this material is re- sponsible for its return to the library from which it was withdrawn on or before the Latest Date stamped below. Theft, mutilation, and underlining of books are reasons for disciplinary action and may result in dismissal from the University. To renew call Telephone Center, 333-84OO UNIVERSITY OF ILLINOIS LIBRARY AT URBANA-CHAMPAIGN L161— O-1096 o, FIELDIANA: BOTANY A Continuation of the BOTANICAL SERIES of FIELD MUSEUM OF NATURAL HISTORY VOLUME 31 The Library of the JAN 1 8 1979 FIELD MUSEUM OF NATURAL HISTORY CHICAGO, U. S. A. 520.5 •FB v-31 TABLE OF CONTENTS PAGE 1. Two New Species of Palms from Nicaragua. By S. F. Glassman ... 1 2. Tropical American Plants, VI. By Louis O. Williams 11 3. Agriculture, Tehuacan Valley. By C. Earle Smith, Jr 49 4. Flora, Tehuacan Valley. By C. Earle Smith, Jr 101 5. Preliminary Studies in the Palm Genus Syagrus Mart, and Its Allies. By S. F. Glassman 145 6. Tropical American Plants, VII. By Louis 0. Williams 165 7. Supplement to Orchids of Guatemala. By Donovan S. Correll . . . .175 8. Preliminary Notes on Scrophulariaceae of Peru. By Gabriel Edwin . . 223 9. New Species in the Palm Genus Syagrus Mart. By S. F. Glassman . . 233 10. Tropical American Plants, VIII. By Louis O. Williams 247 11. Notes on the Flora of Costa Rica, I. By William C. Burger 273 12. A New Eurystyles from Nicaragua. By Alfonso H. Heller 279 13. New Species in the Palm Genus Syagrus Mart. By S. F. Glassman . . 285 14. A Revision of the Family Geastraceae. By Patricio Ponce de Leon . . 303 15. Studies in American Plants. By Dorothy N. Gibson 353 16. Two New Nicaraguan Juglandaceae. By Antonio Molino R 357 17. Studies in the Palm Genus Syagrus Mart. By S. F. Glassman .... 363 18. Tropical American Plants, IX. By Louis O. Williams 401 STUDIES IN AMERICAN PLANTS DOROTHY N. GIBSON TWO NEW NICARAGUAN JUGLANDACEAE ANTONIO MOLINA R. STUDIES IN THE PALM GENUS SYAGRUS MART. S. F. GLASSMAN TROPICAL AMERICAN PLANTS, IX LOUIS 0. WILLIAMS FIELDIANA: BOTANY VOLUME 31 NUMBERS 15, 16, 17, 18 Published by FIELD MUSEUM OF NATURAL HISTORY MAY 23, 1968 JUL 11 1368 STUDIES IN AMERICAN PLANTS DOROTHY N. GIBSON Custodian of the Herbarium FIELDIANA: BOTANY VOLUME 31, NUMBER 15 Published by FIELD MUSEUM OF NATURAL HISTORY MAY 23, 1968 PUBLICATION 1045 Library of Congress Catalog Card Number: 68-26374 PRINTED IN THE UNITED STATES OF AMERICA BY FIELD MUSEUM PRESS Studies In American Plants DOROTHY N. GIBSON During recent studies of the Hydrophyllaceae and Polemoniaceae for the Floras of Guatemala and Peru, it became clear that several concepts of species within certain highly variable genera of these fam- ilies were incorrect, due probably to the limited amount of compara- tive material available to earlier workers. Dr. Standley was becom- ing aware of this situation as early as 1945 when he occasionally noted in manuscript that certain species "might prove to be only varieties." Since then, additional collections, by providing enough material to show the wide range of variability in these plants, have brought us to the conclusion that some of these minor differences are not constant and therefore do not merit specific rank. The notes in this paper were made possible by study of collections borrowed from the United States National Herbarium, New York Botanical Garden and Gray Herbarium of Harvard University, as well as those on deposit in the herbarium of the Field Museum, and I wish to express my thanks to the curators of those herbaria. HYDROPHYLLACEAE Wigandia urens var. caracasana (HBK.) comb. nov. Wigandia caracasana HBK. Nova Gen. & Sp. 3: 128. 1819. W. macrophylla Cham. & Schlecht. Linnaea 6: 382. 1831. W. scorpioides Choisy, Ann. Sc. Nat. Se*r. 1, 30: 249. 1833. W. caracasana var. macrophylla (Cham. & Schlecht.) Brand in Engler, Pflanzenr. IV, 251: 136. 1913. W. caracasana var. calycina Brand, I.e. W. kunlhii var. intermedia Brand, I.e. 137. W. kunthii var. viscosa (Donn.-Sm.) Brand, I.e. W. caracasana var. viscosa (Donn.-Sm.) Macbride, Contr. Gray Herb. New Ser. 49:42. 1917. Mexico to Costa Rica; Colombia and Venezuela. Differs from W. urens only in its lack of bristles on leaves and stems. The leaves usually appear velvety, without bristles on the midvein. The calyx lobes and capsule, however, may be hispid to bristly-hirsute, as in W. urens. Earlier concepts of specific and vari- 353 354 FIELDIANA: BOTANY, VOLUME 31 etal differences were apparently based on such tenuous characters as vesture (highly variable in the genus) and style length (the styles of both the typical species and the variety elongate markedly after an thesis). POLEMONIACEAE Cobaea lutea f. villosa (Standl.) comb. nov. C. villosa Standl. Contr. U. S. Nat. Herb. 17: 454. 1914. Differs from C. lutea only by villous nodes and by occasional vil- losity and/or puberulence of petioles. Known only from El Salvador. Cobaea lutea f. viorna (Standl.) comb. nov. C. viorna Standl. Contr. U. S. Nat. Herb. 17: 453. 1914. Differs from C. lutea only in the absence of long cilia on sepals and leaf bases. Standley, in manuscript, placed his C. viorna in synonymy with C. lutea. Known only from Guatemala. Cobaea pachysepala f. tomentulosa (Standl.) comb. nov. C. tomentulosa Standl. Contr. U. S. Nat. Herb. 17: 457. 1914. Differs from C. pachysepala only in more dense vesture: the stems may be obscurely tomentulose to densely villous, the nodes often densely white-villous, the petiolules short-villous to wooly, the leaf- lets sparsely pubescent to villous beneath, especially along veins, the sepals usually densely tomentulose outside as well as along inside margins, and the corollas may have more scattered puberulence on the lobes. Although Standley, in his original descriptions, states that there are eight or nine seeds in each cell of the capsule of C. pachysepala and four to six seeds in each cell of his C. tomentulosa, I found only six or seven seeds in each locule of both C. pachysepala and C. tomen- tulosa. Further, Standley, in manuscript, says of C. tomentulosa: "Closely related to C. pachysepala, of which it may be only a form or variety." Publications 1045, 1046, 1047, and 1048 UNIVERSITY OF ILLINOIS-URBANA