CONTRIBUTIONS FROM THE GRAY HERBARIUM OF HARVARD 
UNIVERSITY, NEW SERIES, No. XI 
By J. M. GREENMAN. 
Presented by B. L. Robinson, 14 April, 1897. 
I.— REVISION OF THE MEXICAN AND CENTRAL 
AMERICAN SPECIES OF HOUSTONIA. 
HOUSTONIA, Gronov. (Named in honor of Dr. William Hous- 
toun, born in Scotland, 1695, died in Jamaica, 1733.) — Calyx-tube 
usually a little compressed; lobes 4, often with one or more minute 
teeth in each sinus, erect or spreading, persistent, later becoming widely 
separated. Corolla funnelform or salverform, 4-lobed, glabrous or pilose 
in the throat; lobes valvate. Stamens 4, inserted in the throat of the 
corolla ; filaments short or elongated ; anthers dorsally affixed, oblong or 
linear, Disk inconspicuous. Ovary 2-celled; style terete, slender, 
short or elongated ; stigmas 2, linear or linear-oblong; ovules in each 
cell few or many, centrally attached to the median placenta. Capsule 
4 to } inferior, more or less subglobose, obovate, obovate-oblong, or 
turbinate ; seeds crateriform, acetabuliform, or oblong, peltate and 
slightly concave on the hilar surface, usually scrobiculate ; albumen 
horny ; embryo clavate. — Gronov. in L. Syst. Nat. ed. 1; L. ¢ 
no. 70; Benth. & Hook. £. Gen. ii. 60; Gray, Syn. Fl. N. A. i. pt. 2, 
24; Schumann in Engl. & Prantl, Nat. Pflanzenf. iv. Ab. 4, 27. Potre-—~—— 
tia, Gmel. Syst. 263. Panetos, Raf. Ann. Gen. Sci. Phys. v. 227, vi. 81. 
Chamisma, Raf. in Steud. Nom. ed. 2, i. 776, in syn. — Low slender 
“Snnuals, herbaceous perennials, or suffruticose plants with reciprocally 
dimorphous flowers. 
$1. Evnousroniex. Low herbaceous plants often much branched 
from a woody perennial base: leaves ovate, oblong, linear or subterete, — 
hot rigid-setaceous nor acerose-linear : capsule globose, obovate, or oblong- 
obovate, more or less compressed and usually emarginate : seeds cra- 
teriform, acetabuliform, or oblong, peltate and slightly concave on the Z 
hilar surface, scrobiculate. — Gray, Proc. Am. Acad. iv. 313. 
