BOTAI^ICAL. 



THE CACTI OF TRINIDAD. 



By Nathaniel Lokd Brittox, Ph.D., Sc.D., LL.O., 

 Direotoi--in-Chief New York Botanical Garden. 



One of tlic most interesting experiences of ray visit to Trinidad 

 in 1920 was an investigation of the native cacti, wliich was greatly 

 facilitated by Mr. W. G. Freeman, Director of Agriculture. 



Professor GriseJiach, in his Flora of the British Went Indies 

 published from 18.59 to 1864 (the pages bearing his descriptions of 

 Cactaceae were published in 1860) included only one species of the 

 family from Trinidad, evident!}' having had few specimens before him. 



In Mr. Hart's list of tlie specimens in the herbarium of the Eoyal 

 Botanic Gardens, published in 1908, five determined species were 

 recorded ; recent collections have brought the representation of species 

 up to a dozen. 



Most of the kinds native to Trinidad and by far the greater number 

 of individuals inhabit the dry Bocas Islands; there they are very 

 abundant, especially at lower elevations, on Monos, Huevos and 

 Chacachacare, reaching their greatest development numerically on 

 Patos ; they are frecjuent on Gasparee and on the north-western mam- 

 land coast. Three of the species grow here and tliere on trees or rocks 

 over a large part of the mainland of Trinidad. 



The species in the foUowiilg paper not numbered are not native Init 

 are introduced ornamental plants. 



1. Pereskia Pereskia (I-) Karsten [Cactus Ptreskia L. ; Ptre.iJda acukata. 



Miller]. 

 The Barbados or "West Indian Gooseberry or Lemon Vine is a woody 

 climber up to thirt}' feet in length, its branches bearing short recurved 

 spines in pairs or rarely in threes, the lower part of the stem sometimes 

 having some straight and slender spines. Its short-stalked leaven are 

 ovate to lanceolate, entire-margined, two or three inches long, some- 

 what fieshy in texture. Its white, yellowish or pinkish flowers are in 

 small clusters at the ends of twigs, and from an inch to ueai'ly two 

 inches broad. The edible berries, yellow to red, are somewhat more than 

 half an inch in diameter. 



The plant is commonly cultivated for its fruit in tropical America. 

 I observed one climbing on a tree at Maqueripe, apparently Vvild and 

 native. 



Pereskia grandifolia Hawcrth, native of Brazil, a shrub often 

 six feet high, armed with straight long slender spines, its leaves four to 

 six inches long, its flowers rose-colo\ired, rarely white, is often planted 

 for ornament and makes effective hedges. It ha^ been confused with 

 T. Bleo (H.B.K.) D.C. of Colombia and Panama. 



