290 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



2. PERITOMA DC. 



Coarse glabrous branching annuals, 1 meter high or less; leaves alternate, trifolio- 

 late; leaflets lanceolate to elliptic, acute or obtuse, entire; petals yellow, rose purple, 

 or rarely white; stamens 6, long-exserted ; pods stipitate, cylindric, 10 cm. long or 

 less, with few or many large seeds. 



KEY TO THE SPECIES. 



Petals rose purple, rarely white; capsules 5 to 10 cm. long; seeds 



numerous 1. /'. serrulatum. 



Petals yellow; capsules 2 cm. long or less; seeds 6 or fewer 2. P. breviflorum. 



1. Peritoma serrulatum (Pursh) DC. Prodr. 1: 237. 1824. 



Rocky Mountain bee plant. 



Cleome serrulata Pursh, Fl. Amer. Sept. 441. 1814. 



Cleome integrifolia Torr. & Gray, Fl. N. Amer. 1: 122. 1838. 



Type locality: "On the banks of the Missouri." 



Range: Saskatchewan and Idaho to Arizona and Missouri. 



New Mexico: North of Gallup; Chama; Zuni; Santa Clara Canyon; Santa Fe; 

 Las Vegas; Pecos; Folsom; Frisco; Gila; Mangas Springs; "White Mountains. Hills 

 and plains, in the Upper Sonoran and Transition zones. 



A common range weed, occupying considerable areas of land that has been over- 

 stocked. The flowers supply large quantities of nectar, which fact gives the common 

 name. 



Peritoma sonorae (A. Gray) Rydb. has been reported from New Mexico, but we 

 have seen no specimens. It may be distinguished from P. serrulatum by its small 

 pods, less than 15 mm. long, and by having its sepals distinct instead of united at 

 the base. 



2. Peritoma breviflorum Woot. & Standi. Contr. U. S. Nat. Herb. 16: 128. 1913. 

 Type locality: Dry, stony hills about Shiprock, New Mexico. Type collected 



by Standley (no. 7282). 



Range: Northwestern New Mexico and northeastern Arizona, probably in adjacent 

 Utah and Colorado. 



New Mexico: San Juan Valley. Dry hills and plains, in the Upper Sonoran 

 Zone. 



3. CLEOMELLA DC. 



Erect annual, 30 to 60 cm. high, with trifoliolate leaves; leaflets oblong or spatu- 

 late-obovate; petals yellow; stamens 6, exserted; pods long-stipitate, several-seeded, 

 the valves obliquely conic. 



1. Cleomella longipes Torr. JournT Bot. Kew Misc. 2: 255. 1850. 



Type locality: "Valley near San Pablo, Chihuahua, and near San Francisco, 

 San Luis Potosi, Mexico." 



Range: Western Texas to Arizona and Sonora." 



New Mexico: Dog Spring (Mearns 2379). 



A rather uncommon plant of the Southwest. The peculiar small, 2-valved pod 

 with conical valves and the long stipes serve to distinguish the genus from our others. 



4. WISLIZENIA Engelm. 



Erect, much branched annual; leaves trifoliolate, the leaflets oblong to obovate; 

 petals small, yellow; stamens 6, exserted; pods long-stipitate, small, 2-seeded, the 

 valves ellipsoid, indurate, reticulate. 



