128 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
side near the apex; leaves 4 to 6 mm. long, 2 to 3 mm. wide, oblong to oblong-ovate 
or oval, obtuse or rounded at the apex, thick and coriaceous, glabrous, flat or nearly 
so, shining on the upper surface, abruptly contracted at the base into a very short 
petiole; flowers few, short-pediceled, in solitary or clustered, pedunculate, terminal 
cymes; pedicels glabrous; calyx 2 mm. long, glabrous, thick and firm, the lobes ob- 
long to oval or ovate, obtuse or acutish, longer than the tube, with low and incon- 
spicuous intermediate lobes; corolla tube 3.5 mm. long, much longer than the lobes, 
these densely pilose within with coarse white hairs; capsule 2 mm. long. 
Type in the U. S. National Herbarium, no, 675707, collected on bare rock slopes 
at the summit of Chiriquf Volcano, Panama, at an altitude of 3,374 meters, March 
12, 1911, by William R. Maxon (no, 5349). 
ADDITIONAL SPECIMENS EXAMINED: 
Panama: Volcan de Chiriquf, April, 1899, K. Sapper. 
Costa Rica: Volcién de Pods, Province of Alajuela, alt. 2,700 meters, J. D. Smith 
6635. Volcdn de Turrialba, Province of Cartago, alt. 2,800 meters, Ptttier 
(J. D. Smith, no. 7506; Inst. Fis. Geogr. Costa Rica, no. 13239). 
Related to A. hartwegianum and A. cephalanthum, of Colombia, by its pubescent 
corollas, but readily distinguished by its small, obtuse leaves and loose inflorescence. 
Only one other species of the genus is known from Central America, A, shannoni, 
described from Guatemala, 
Arcytophyllum shannoni (Donn. Smith) Standley. 
Mallostoma shannoni Donn. Smith, Bot. Gaz. 18: 203. 1893. 
NEW SPECIES OF PSYCHOTRIA FROM PANAMA. 
Psychotria is represented in Panama by a larger number of species 
than any other genus of the Rubiaceae. At present 26 species are 
known from the region, but when remote parts of the country are 
explored this number will doubtless be greatly increased. An excel- 
lent account of the West Indian Psychotrias by Dr. Urban has 
appeared recently,! which has been of great service in the study of 
the Panamanian species. Most of the forms found in Panama are 
confined, so far as known, to continental North America, end prob- 
ably many of them are endemic. 
Psychotria aggregata Standley, sp. nov. 
Branches stout, succulent, glabrous, lineolate; stipules united at the base, green, 
each abruptly contracted into a narrowly oblong tip 3 mm, long; petioles 3 to 3.5 cm. 
long; leaf blades oblanceolate, 12 to 20 cm. long, 3 to 5 cm. wide, acuminate, atten- 
uate at the base, subcoriaceous, glabrous, dull green on the upper surface, whitish 
beneath, prominently veined, the veins coarse, white beneath; peduncles axillary, 
4 to5 cm, long, minutely puberulent, bearing mostly 3 pedunculate, densely many- 
flowered heads, the heads composed of few-flowered fascicles each subtended by 
several narrowly oblong to ovate, acute or acutish, ciliolate, green bracts, these 
equaling or slightly exceeding the calyces; calyx and ovary subequal in length, 
together 3 mm. long, the calyx lobed to the middle, whitish, the lobes ovate, obtuse 
or acutish, minutely and sparsely puberulent; corolla white, 4 mm. long, puberulent 
outside, the tube dilated upward, the lobes very short, hooded; fruit not seen. 
Type in the U. 8. National Herbarium, no. 677655, collected in the humid forest. 
between Alto de las Palmas and top of Cerro de la Horqueta, Chiriquf, Panama, at an 
altitude of 2,100 to 2,260 meters, March 18, 1911, by H. Pittier (no. 3264). 
* Urban, Symb. Antill. 7: 483-477. 1913. 
