ON SOUTH-AMERICAN APOCYNACEZX. 95 
3-5 lines long, shortly branched, and bearing a capitate cluster of very small, rufously 
pruinose flowers, 2 lines long, on pedicels 4 line long, with small bracteoles; sepals sub- 
acute, membranaceous, 1 line long; corolla subpuberulous outside; tube 1 line long; 
segments lanceolate, subreflexed, glabrous inside, dextrorsely convolute in sestivation, 
1 line long; disk of 5 smooth, fleshy lobes; follicles 2 (one sometimes abortive), linear, 
stoutish, 2-3 in. long, containing many oblong flat seeds with narrow winged margins, 
without any coma. 
3. Tuyrsanruus BENTHAMIANA, nob.: Forsteronia Benthamiana, Müll. l. c. p. 106. In Brasilia: v. s. 
in herb. meo et alior. San Carlos, Rio Negro (Spruce 3481). 
A species much resembling the two preceding. Its branches are glabrous, striolate, 
verrucously lenticellate, with axils 14-12 in. apart; leaves lanceolate oblong, roundish 
or subacute at the base, with a very narrow acute acumen, margins revolute, very 
glabrous, with arcuate, fine, semi-immersed nerves, the midrib at its junction with the 
petiole showing a yellow granular gland, sometimes split into 2 or more distinct 
glandules, as in the typical species, ferruginously opake beneath, with a prominent 
fuscous midrib, prominulent fine nerves and reticulated veins, 4-6] in. long, 13-14 in. 
broad, on channelled petioles 2-8 lines long; panicles subterminal and axillary, 
rufescently puberulous, 24-3 in. long, on a rather slender peduncle bare for 14 in., 
bearing above several branchlets 3 in. long, bare at the base for half their length, and 
bifidly divided, with 3-4 flowers on pedicels 1 line long, and minutely bracteolated ; 
sepals acute, X line long; corolla also pruinosely tomentellous, 2-21 lines long, with a 
very short tube; segments lanceolate, with dextrorse convolution. 
4. THYRSANTHUS SPICATUS, nob. : Forsteronia spicata, Meyer, Esseq. p. 135; A. DC. l c. p. 437 : Echites 
spicata, Jacq. Am. p. 34, tab. 29: Parsonsia spicata, R. Br. Mem. Wern. Soc. i. p. 65. In Carta- 
gena (Jacq.): v. s. in herb. Mus. Brit. Campeche (Houston). 
The plant of Houston agrees well with the drawing of Jacquin, who describes it as a 
lofty climber, the main stem being 1 in. thick, with alternate remote branches whose 
axils are nearly 2 in. apart. It exudes a copious milky juice. The leaves are opposite, 
very spreading, elliptic oblong, roundish at the base, and recurved upon the petiole, 
with a short suddenly acute reflexed acumen, rigidly chartaceous, with revolute margins, 
green above, corrugulate, with a flattened midrib and about 10 pairs of divaricate 
arching nerves, sulcate along them and the immersed reticulated veins, with a large 
granulated gland at the base of the midrib, pale, ferruginous, and opake beneath, midrib 
and nerves flattened, reddish, 41-53 in. long, 23-2] in. broad, on channelled petioles 
3 lines long; panicles opposite, densely thyrsoid, 1-13 in. long, 3 in. broad, on short 
peduncles, bearing very numerous, crowded, subsessile flowers, 2 lines long; sepals 
ovate, rigid, subimbricated; corolla white, with a very short tube, villous inside ; 
segments acutely oblong, equilateral, with reflexed margins, twice the length of the 
tube; anthers exserted, conniving in a cone; disk of 5 lobes, as long as the 2 villous 
ovaries. 
