1917] Butters & St. John,— North American Lathyrus 159 
Macoun, Can. Geol. Surv. no. 34,218; twenty miles up the Kaminis- 
tiqua, Lake Superior, July 12, 1869, John Macoun no. 20. Wisconsin: 
Green Bay, June 9, 1898, J. H. Schuette; Despere Ledge, June 30, 
1882, J. H. Schuette (rype in Hb. Gray). Minnesota: Nicollet, 
June, 1892, C. A. Ballard; Lake City, June 25, 1883, W. H. Manning. 
Manirospa: Lake Winnepeg Valley, 1857, Bourgeau. Nortu 
Dakota: thickets in Turtle Mountains, July 24, 1902, J. Lumell. 
SASKATCHEWAN: 1858, E. Bourgeau; Cypress Hills, June 27, 1894, 
John Macoun. 
In the study of the varieties of Lathyrus venosus described above, it 
has become evident that there has been much confusion in the nomen- 
clature of certain western species of this genus. This confusion has 
arisen chiefly from varying interpretations of L. decaphyllus and 
Vicia stipulacea of Pursh, and L. polymorphus of Nuttall. 
Lathyrus decaphyllus Pursh, Fl. Am. Sept. ii. 471 (1814), is described 
as follows: “L. caule tetragono, stipulis semisagittatis linearibus, 
foliis 5-jugis: foliolis oblongo-ellipticis mucronatis, pedunculis 3-4 
floris. On the banks of the Missouri. 2. v. s. Flowers purple, 
large; pods large.” The plants which Pursh described in the body 
of his flora as from “the banks of the Missouri” were mainly those 
collected by Lewis and Clark on their exploring expedition, but this 
species is not mentioned in any of the recent editions of their Journals 
nor is it among the Lewis and Clark plants now deposited in the 
herbarium of the Academy of Natural Sciences of Philadelphia. A 
manuscript note of Dr. Gray’s shows that the type specimen was not 
among the Pursh plants in the Lambert Herbarium, when he exam- 
ined them. It is therefore exceedingly improbable that the type of 
this species is now in existence, and consequently the interpretation 
of it must rest entirely upon the description in Pursh’s Flora. In 
1818 Nuttall ! interpreted L. decaphyllus Pursh as identical with Vicia 
stipulacea Pursh. There seems to be little justification for this, as 
the latter species has narrowly linear-lanceolate leaflets, instead of 
the oblong-elliptic ones attributed to L. decaphyllus. Following Prof. 
N. L. Britton,? recent American authors have applied the name 
L. decaphyllus to a low, large-flowered species of the Rocky Moun- 
tains of Colorado, New Mexico and Arizona. This species is said to 
occur as far north as southern Idaho, but even granting the correct- 
ness of this report, it still fails by three hundred miles to reach the 
1 Nuttall, T., Genera of N. Am. PL. ii. 97 (1818). 
2 Mem. Torr. Bot. Club, v. 207 (1894). 
