192 Proceedings of the Biological Society of Washington. 



Other specimens that closely approach Howell's type are the following, 

 all referred to L. nuttallii Wats.: 



Lake of the Woods, Oregon, Coville & Leiberg No. 48; 



Klamath Valley, Oregon, Cronkhite No. 15; 



Mount Rainier, Wash., Flett No. 1261; 



Colby, Butte Co., Cal., Mrs. R. M. Austin No. 702. 



On the whole we would consider L. lanceolatus at best a subspecies of 

 L. nuttallii. 



Lathy rus pauciflorus Fernald. 



Lathyrus pauciflorus, like some other species of the genus, has both broad 

 and narrow leafed variations. The latter especially have been very puz- 

 zling to students as evidenced by the numerous names which appear on 

 the labels of specimens. Along with the variation of the leaflets there 

 is a corresponding variation in the stipules, so that broad leaflets are 

 usually associated with broad stipules and narrow leaflets with narrow 

 stipules. 



There is also wide variation in the size of the flowers, depending in part 

 on where the plant grew. In normal plants of L. pauciflorus in Eastern 

 Washington the flowers are about 20 mm. long, but in starved specimens 

 from arid situations they are only 15 mm. long. It is evident therefore 

 that the size of the corolla is a character whose value can easily be exag- 

 gerated. In general, however, the Mexican and Arizonan forms of the 

 species as here interpreted have for the most part smaller flowers than the 

 northern forms. • 



From a study of the extensive series of material which has accumulated 

 in the National Herbarium it seems most logical to consider L. pauciflorus 

 a variable species and to include in it as subspecies the plants described 

 under the names L. parvifolius Watson, L. utahensis Jones, L. pauciflorus 

 tenuior Piper and L. brownii Eastw. The principal distinguishing char- 

 acters are displayed in the following key: 



Flowers usually 18-20 mm. long. 



Leaflets linear to linear-lanceolate L. pauciflorus tenuior. 



Leaflets broader. 



Leaflets elliptic to ovate-lanceolate, acute L. pauciflorus. 



Leaflets oval to ovate, obtuse L. pauciflorus utahensis. 



Flowers 12-16 rarely 20 mm. long. 



Leaflets oval, elliptic or ovate.. L. pauciflorus schaffneri. 



Leaflets linear to narrowly-oblong... ..L. pauciflorus brownii. 



In the cases of tenuior and utahensis there is scarcely room to question 

 their merely subspecific rank, as the differences are slight and the inter- 

 grades numerous. 



As regards schaffneri the case is more complex, as there is wide variation 

 both in the form of the leaflets and in the size of the flowers. Among 

 Mexican specimens, Pringle's No. 8810 might well be referred to typical 



