444 
A preliminary Revision of the Genus Lathyrus in North and 
Central America. 
By THEODORE G, WHITE. 
The following is an attempt to correlate, and classify the 
various descriptions and herbarium material of North American 
Lathyri. Much confusion has existed in the determination of 
specimens of this genus up to the present time, and evidently the 
species thus far defined are not sufficent to embrace all the material 
collected. 
From the fact that each collection so far examined has af- g 
forded so many developments, we are certain that much interest- , 
ing material awaits description. The present abstract is pub- 
lished in the hope of bringing forth additional material and notes 
from collectors in the field,-especially in the West and Southwest, a 
before the work is completed. Such information will be most 
gratefully received. ; 
Only two attempts have previously been made to enumerate = 
the species of the genus. The first was by Alefeld (Bonplandia, 
June, 1861), who placed all the American species in the genus 
Orobus; the second, by Watson (Am. Jour. Sci., Feb., 1876), 
_who enumerated thirteen species; while several additional specte> 
chiefly by Prof. Greene and by Dr. Watson have since been pub- 
Ished. 
I am indebted to Prof. N. L. Britton for guidance throughout, 
and for the use of collections placed at my disposal by Columbia 
College, Harvard University, United States Department of Agne 
culture and the University of California, which have been exam: : 
ined as well as several private herbaria. 
LATHYRUS L. Sp. Pl. 733 (1783): 
Stem erect or climbing by mostly trifid tendrils ; stipules varr" 
ably semi-sagittate; leaves abruptly pinnate, of 1-7 pairs of leaflets “ 
leaflets mucronate; peduncles axillary; the raceme shorter thaw 5 
equalling or exceeding the leaves; corolla papilionaceous, pg 
panulate at base and not funnel-form as in Vicia; wings free es , 
_ or only slightly adherent to the middle of the keel, while thos® © 
Vicia are adherent ; sheath of the filaments cylindrical and cut « 
_ abr uptly at tight angles, and not oblique at the apex; *”™ 
