24 ON SOUTH-AMERICAN APOCYNACEA. 
2. THYROMA DECIPIENS, nob.: Aspidosperma decipiens, Müll. l. c. p. 398. In Venezuela; v. s. in herb. 
meo et aliorum Rio Maypure, Rio Orinoco (Spruce 3657). 
A species near the preceding, with slender verruculose branches, having opposite, or 
by abortion alternate axils, 3-4 lines apart: the oblong-ovate leaves, with rounded or 
emarginated summits, are 2 in. long, 1 in. broad, on a slender petiole 3 lines long; they 
are shining and glabrous above, with about 15 pairs of nerves, yellowish opake beneath, 
obsoletely tomentous under a lens, with prominent midrib and nerves: the panicle is 
6 lines long, with about 4 alternate branches 3 lines long, bearing few flowers on very 
short pedicels; the structure of the flower as in the foregoing species. 
3. Tuyroma NITIDA, nob.: Aspidosperma nitidum, Benth. MS.; Müller in Mart. Fl. Bras. fasc. 26. 
p. 59. In Amazonas: v. s. in hb. meo et alior. Barra do Rio Negro (Spruce 1657). 
A species, compared with the two former, inaptly called nitida: the axils of the sub- 
angular verruculose branchlets are 43 in. apart: the opposite leaves, often alternate, 
are oblong, obtuse, subcoriaceous, with somewhat revolute margins, are 23-3 in. long, 
13-13 in. broad, on a petiole 33-4 lines long, they are green, subopake above, closely 
impressed-punetate, and with about 16 pairs of nerves, of a yellowish dirty white 
beneath, with an impressed scrobiculate surface, with prominent midrib and suleated ` 
nerves: the axillary panicle, densely corymbose, on a bifurcated peduncle 4 lines long, | 
bearing 2 capitate heads of small flowers, 4-5 lines in diameter; the pedicels are 3 line 
long, with 3 short ciliated bracts at base: the oval subacute sepals, puberulous outside, 
are $ line long; the corolla, 2 lines long, has a tube half that length, with border- 
segments lanceolate-oblong, nearly erect, subfleshy and sinistrorsely convoluted ; disk, 
ovary, style, and.stigma as in the typical species. 
4. THYROMA POLYNEURA, nob.: Aspidosperma polyneurum, Müll. in Mart. Fl. Bras. l. c. p. 57. In 
Brasilia, prov. Rio de Janeiro : v. s. in hb. Hook. (Sellow 632), Corcovado (Gardn. 5363). 
A tree 80 feet high, giving a useful timber called “ peroba,” with a bitter bark: the 
specific name was applied because of its numerous fine parallel nerves, about 60 pairs, 
united by a common line within the revolute margin, and with fine reticulations between ` 
them: the leaves, sometimes subopposite, more often alternate, are glabrous, sub- 
membranaceous, elliptie, obtuse at the summit, gradually acute below, 21-31 in. long, 
+1 in. broad, on petioles 4-5 lines long: the panicle is 9-10 lines long, with few 
branches and few flowers; the pedicel is 1 line long, the calyx $ line, corolla 3 lines ` 
long, tube narrowed gradually below, puberulous outside, retrorsely pilose inside, with ` 
5 oblong obtuse erect segments, sinistrorsely convoluted, pilose within, 3 length of tube; 
5 small scales within the mouth of the tube opposite the segments ; 5 short stamens beneath ` 
and alternate with the scales, anthers cordate at the base, on very short filaments: follicle ` 
single, very much flattened, straight on the dorsal side, semioblong on the other, both ` 
ends acute, 15-21 lines long, 41-5 lines broad; seeds scutellate and tomentellous at the ` 
upper moiety, broadly winged and glabrous below. : 
5. Tayroma SELLOWI, nob.: Aspidosperma Sellowii, Müll. ibid. p. 56. In Brasilia meridionali : v. $ 
in hb. Hook. (Sellow 1204). 
The leaves are like those of the preceding, but with only 10 pairs of immersed nerves, | 
