580,5 FB v.7 1930 cop. 2 Inc. 2_, FIELD MUSEUM OF NATURAL HISTORY FOUNDED BY MARSHALL FIELD, 1893 PUBLICATION 302 BOTANICAL SERIES VOL. VII, No. 4 THE RUBIACEAE OF VENEZUELA BY PAUL C. STANDLEY ASSOCIATE CURATOR OP THE HERBARIUM, DEPARTMENT OP BOTANY B. E. DAHLGREN ACTING CURATOR, DEPARTMENT OF BOTANY EDITOR NOV a CHICAGO, U. S. A. OCTOBER 12, 1931 FIELD MUSEUM OF NATURAL HISTORY FOUNDED BY MARSHALL FIELD, 1893 PUBLICATION 302 BOTANICAL SERIES VOL. VII, No. 4 THE RUBIACEAE OF VENEZUELA BY PAUL C. STANDLEY ASSOCIATE CURATOR OF THE HERBARIUM, DEPARTMENT OF BOTANY 0? B. E. DAHLGREN . ' ** ACTING CURATOR, DEPARTMENT OF BOTANY V U V 1 Q *3 1 EDITOR CHICAGO, U. S. A. OCTOBER 12, 1931 PRINTED IN THE UNITED STATES OF AMERICA BY FIELD MUSEUM PRESS v.V THE RUBIACEAE OF VENEZUELA PAUL C. STANDLEY Venezuela, with almost 600,000 square miles of territory, is substantially larger than the neighboring republic of Colombia, con- sequently, upon the basis of area alone, other conditions being equal, one would expect to find more Rubiaceae in Venezuela than in Colombia. The present list enumerates 81 genera and 351 species, a number which, it is scarcely necessary to state, is far short of the total actually existing in the country under consideration. Venezuela is more than twice as large as Texas. Because of the difficulties of travel in the greater part of the country, only a relatively small portion of it ever has been seen by a botanist and many parts still are quite unexplored. Indeed, even the boundaries are yet a matter of uncertainty, and on that account it is possible that there are listed on the following pages some species that have not been collected yet within the proper limits of Venezuela. Except for certain small regions such as those about Caracas and Tovar, no part of Venezuela is well known botanically, in spite of the fact that so many specimens of plants have been gathered in the country. Most of the collections have been obtained in the more densely settled portions, the chief exceptions being those from Mount Roraima and Mount Duida, and from the Orinoco and its tributaries. The Orinoco region must hold scores of Rubiaceae unknown to science or recorded hitherto only from Brazil. Even in the northern states, where most of the collecting has been done, new species of Rubiaceae are discovered by almost every collector. Venezuela is fortunate in having been visited by many able botanical collectors who have been charmed but almost discouraged by the luxuriant variety of its vegetation. The first important plant collection made in the republic was the classical one of Humboldt and Bonpland, from the Orinoco and the environs of Caracas. From their specimens Kunth described many endemic Venezuelan Rubiaceae. A curious confusion arose regarding the publication of the Hum- boldt and Bonpland species of Rubiaceae. Specimens of some of them, especially the Psychotrias, were submitted to Willdenow, and brief descriptions of them were included by Roemer and Schultes in the part of their Systema which appeared in 1819. The same 343 344 FIELD MUSEUM OF NATURAL HISTORY BOTANY, VOL. VII species, or most of them, at least, were described by Kunth in a part of the Nova Genera that appeared the following year. Kunth, however, makes no mention of the Willdenow names. In some cases the same name is applied in both works to the same plant, but frequently the specific names are different in the two works. Even more confusing is the fact that a certain specific name sometimes is applied by Roemer and Schultes to one plant, and the same name by Kunth to a quite different one. It is unnecessary to enumerate here all the collectors who have contributed to the present knowledge of Venezuelan Rubiaceae, for their work has been described by Pittier in his Plantas Usuales de Venezuela. Many species of Rubiaceae still are known only from the types obtained along the Orinoco and Rio Negro by Richard Spruce, foremost and most fortunate of the botanists who have worked in the Amazon Valley. Knowledge of the Rubiaceae, as well as of the whole flora of Venezuela, has been vastly increased during the past twenty years by the labors of a botanist who already had accomplished enough to represent an enviable life work for one man. Henry Pittier, chiefly by his own field work, but also by his stimulation of the efforts of others, has added to the flora of Venezuela many hundreds of species, chiefly new ones, but also many that were known previ- ously only from Colombia or the Guianas. Only his personal friends will realize under what difficult conditions his enthusiasm has impelled him to carry on floristic work in a region where it was so much needed. The best and only important work relating to the Venezuelan flora is his Plantas Usuales de Venezuela, published at Caracas in 1926. Like his already classic work of similar form upon the plants of Costa Rica, it is an encyclopedia of information regarding the area covered. With no intention of drawing comparisons, it is necessary to mention here a publication quite different in scientific value, Knuth's Initia Florae Venezuelensis (1926-28). Certainly the plan of publish- ing a plant list of any South American country is a praiseworthy one, and, when properly executed, deserves the most diligent support; but it is imperative to give a word of caution to prospective students of the Venezuelan flora regarding this work, although they soon will discover its defects themselves. In Knuth's list the writer has investigated only the Rubiaceae, but presumably other families are treated in the same manner. The THE RUBIACEAE OF VENEZUELA 345 fact that some collections are listed under wrong specific determina- tions is not remarkable, and in the case of the Rubiaceae of Knuth's work the present writer undoubtedly is responsible for some of the errors perpetrated. There is less excuse, however, for the omission of dozens of species reported from Venezuela in the Flora Brasiliensis. No student of the tropical American flora will go far unless he con- sults frequently the volumes of that unique work, one of the few whose cost in dollars is proportionate to its practical scientific value. Still less excusable is the fact that in Knuth's enumeration of Venezuelan plants the same species often is entered two to four times under as many specific or generic names! Under certain circumstances such carelessness might be understood or excused, but in most of the instances in mind, the errors might have been remedied by consultation of the Flora Brasiliensis, or of the no less accessible publications by Urban upon the flora of the West Indies. From a geographic standpoint the Venezuelan Rubiaceae are associable mostly with several rather well-marked provinces. Those of the Andes are chiefly species that occur in the higher mountains of Colombia. Those of the northern plains and lower mountains either are endemic or extend into the Guianas and the West Indies. Along the Orinoco and Rio Negro there is a host of species, especially in Psychotria, which range to Amazonian Brazil, or else find their closest relatives there. Two Venezuelan localities possess peculiar and endemic floras Mount Roraima and Mount Duida, both in the southern part of the country. Mount Roraima usually is associated with British Guiana, perhaps because most explorers have approached it from that direction, but the Venezuelan boundary crosses its summit. On that account, naturally, all the species recorded from the moun- tain deserve a place in any enumeration of Venezuelan plants. As is well known, Roraima's flora, at least that of the upper slopes, consists almost wholly of endemic species. It is only recently that Mount Duida, which lies well to the west of Roraima, has been ascended and explored, by G. H. H. Tate of the American Museum of Natural History. The Rubiaceae of Mr. Tate's collection were submitted to the writer for determination by the New York Botanical Garden. It is planned to publish a complete report upon his whole collection, but, through the courtesy of Dr. H. A. Gleason, it is possible to enumerate here the Rubiaceae col- lected by Mr. Tate, which form a substantial addition to the list. 346 FIELD MUSEUM OF NATURAL HISTORY BOTANY, VOL. VII One might well expect to find upon Mount Duida some, at least, of the Roraima Rubiaceae, but that, surprisingly enough, is not the case. Although the Duida plants are related to Roraima species, they are clearly distinct. Especially noteworthy are two new genera, Gleasonia and Duidania, described on later pages of this report. As in the case of the preceding parts of the present volume, in the preparation of this Venezuelan list the writer has been fortunate in being able to study at Field Museum a large amount of material lent by American and European herbaria. The institutions whose collections have been examined wholly or in part are the following: Field Museum of Natural History (indicated in the lists of speci- mens cited by the letter F); Royal Botanic Gardens, Kew (K); Botanic Garden and Museum, Berlin-Dahlem (B); Riksmuseets Botaniska Afdelning, Stockholm (S); Jardin Botanique Principal, Leningrad (L); Mus&um d'Histoire Naturelle, Paris (P); United States National Museum, Washington (W); Gray Herbarium of Harvard University (G) ; New York Botanical Garden (Y) ; Missouri Botanical Garden (M). To those in charge of these collections, who have lent material for study, the writer here expresses his sincere and grateful appreciation of the courtesies thus extended. The writer wishes to express also his personal appreciation of the courtesy of Dr.