230 TBINIDAD AND TOBAGO BULLETIN. \XIX. 4. 



A TRINIDAD TRBE-GENTI A.N. 



By Dr. N. L. Brixton, 



Director-in-Chief, New York Botanical Garden. 



One of the most interesting wild plants observed by us in Trinidad 

 during April, 1920 was a small tree of the Gentian family, growing at the 

 top of the precipitous northern slope of Mount Tucuche a short distance 

 from the summit ; we had gone a few feet off the excellent path up this 

 mountain and plunging through dense undergrowth came out at the top 

 of the slope and face to face with this curious plant, which is probably 

 rare, for none of the several botanists who have previously explored the 

 mountain appear to have found it ; at all events it has never been 

 described and is thus new to Science. 



Other shrubs and small trees of this family are known in several 

 genera inhabiting South America, and I had read descriptions of them 

 and studied dried specimens of some, but had never before had the good 

 fortune of seeing one living. At first glance this Trinidad species in no 

 manner suggested any gentian of any member of the family known to 

 me and it was only after I had broken off a flowering branch and got a 

 good look at the blossoms that its relationship became apparent. The 

 tree is two or three times the height of a person, with a few nearly 

 upright branches and a smooth trunk three or four inches in diameter 

 near the ground ; it has broad dark green leathery, stalked leaves and 

 terminal clusters of greenish-yellow bell-shaped flowers about an inch 

 long. I append a technical description : 



Chelonanthus Arboreus spec. nov. 



A tree up to 5m. high, with few virgate branches, glabrous throughout. 



Leaves elliptic, coriaceous, 5 -8cm. long, 2*5 — 4"5cm. wide, the 

 midvein prominent beneath, the lateral venation wholly obscure, the 

 apex acute or short-acuminate, the base narrowed or subcuneate, the 

 rather stout petioles l-2cm. long ; panicles stalked, binate, several 

 flowered ; bractlets lance-subulate, 3-5mm. long ; pedicels stout, 

 6-12 mm. long, decurved in fruit ; calj'x campanulate, 8-10 mm. long, 

 rounded at the base, its short lobes rounded ; corolla tubular-campanulate, 

 greenish-yellow, 2-2*5 cm. long, its short lobes rounded ; stamens about 

 as long as the corolla-tube ; stigmas flat, oblong. 



Type specimen from forested bank near summit of Mount Tucuche. 

 Trinidad (Britton, Ha.~en and Mendelson 1295). Good specimens, 

 collected by Mr. W. G. Freeman at the same place are preserved in the 

 herbarium of the Trinidad Department of Agriculture. 



I include this species in the genus Chelonanthus with some hesitation, 

 inasmuch as the type species is herbaceous, as also several of the others, 

 but a species much resembling the Trinidad plant, inhabiting St. Vincent 

 and Guadeloupe, first described by Swartz as Lisianthus frigidus, has 

 been referred by recent authors to Chelonanthus and I am quite 

 confident that the two are congeneric. C. frigidus (Sw.) Urban, is much 

 less woody than the Trinidad species, with relatively thin leaves and 

 solitary or few, much larger flowers. C. frigidus has also been referred 

 to another genius, Calolisianthus, by Gilg., but it is not much like its 

 typical species. The tetrad pollen of all these plants is very interesting 

 under high magnification. 



