ROBINSON. — MEXICAN PLANTS. 823 
mens bear out Dr. Watson’s amplification of the characters, and confirm 
its distinctness from ZL. elliptica, Reichb. f. 
IsOCHILUS UNILATERALE. Glabrous: stems several, slender, sim- 
ple, 8 inches in height, roughened especially near the base by numer- 
ous minute warts: leaves linear, slightly retuse, rather rigidly erect, 
13-2 inches long, finely striated: racemes single, simple, terminal, 
secund, about 7-flowered: bracts oblong, obtuse, purplish; pedicels 
exserted 2-3 lines: flowers large for the genus, 6 lines long, purple, 
strongly gibbous upon the side toward the labellum, not noticeably 
fleshy: sepals subequal in length, carinate, acutish: petals oblong, 
obtusish, slightly broader than the sepals, and not carinate; labellum - 
lance-oblong, with the sigmoid flexure characteristic of the genus but 
without lateral lobes: fruit 6 lines in length. — Collected on oaks, 
Tamasopo Cafion, 23 June, 1891 (no. 5116). This species, with much 
the habit of Z. lineare, R. Br., has larger more one-sided flowers in 
a looser raceme. 
NeMAsTYLIS FLAVA. Bulb ovoid, 8 lines in diameter, dark brown, 
with a tuft of fibrous roots at the base; stems or rather scapes 1 
to 3, slender, simple, leafy only at the base, 8-10 inches high, bearing 
at the summit a single 2-3-flowered spathe of 3 unequal lance- 
linear or linear-oblong acuminate bracts (the largest 14-13 inches in 
length): the outer leaves reduced to acute scale-like sheaths; the 
inner narrowly linear, attenuate, equalling the scape: pedicels about 
an inch long: flowers 1-1} inches in diameter, bright yellow: seg- 
ments oblanceolate to obovate, acuminate ; the outer 7 lines in length; 
the inner two thirds as long and with rounded thickened areolx at the 
base : filaments connate ; column 14 lines high ; anthers 2} lines long, 
inclining to curl with age: capsule ovoid, smooth, shallowly six-fur- 
rowed, 3 inch in length. — Collected on gravelly soil near Guadalajara, 
23 June and 21 August, 1893 (no. 4490). Near W. bracteolata, 
Baker, but with single heads, distinctly unequal periauth segments, 
and, of course, different geographic position. 
Dioscorea GRaNpiFoLia, Schlecht. Mr. Pringle’s no. 4547, col- 
lected on talus of cliffs, barranca of Tequila, 4 October, 1893, corre- 
sponds well to the characterization of this species. The fertile plant, 
of which I find no description, furnishes the following characters : 
fruiting racemes about 3 inches in length upon peduncles about an 
inch long: fruit elliptic in outline, reflexed-spreading, not closely 
imbricated, 7 lines in length, half as wide. ee 
D. Princtet. Glabrous: stem twining: leaves ovate, acuminate, 
entire, cordate with an open sinus, 9-l1-nerved, somewhat paler 
