LIST OF THE PLAXTS COLLECTED 51 



53. VITACEAE (Vine Family) 

 279 Parthenocissiis litacca A. S. Hitch. Virginia Creeper. 



Rather plentiful in groves, especially in ravines of buttes. 

 2&o J'itfs I'ulpina L. River-bank Grape. 



Rare ; most common in East Short Pines. 



54. MALVACEAE (Mallow Family) 



281 Mak'astnun coccineum (Pursh) Gray. False Mallow. 

 Very abundant on steppe, especially along roadsides. 



55. VIOLACEAE (Violet Family) 



282 J'iola canadcnsis L. 



Common on moist banks about the buttes and occasionally 



on other streams. 

 ^283 J'iola retusa Greene? 



Rare Little Missouri and Shaw Creek. 

 *284 J'iola i-allicola A. Xels. 



Abundant along valley banks. 



56. LOASACEAE (Loasa Family) 



285 Mentzelia dccapctala (Pursh) Urban & Gilg. 



This large and showy herb grows on steep clay banks, less 

 common than the following. 



286 Mcntsclia nuda (Pursh) T. & G. 



Fairly numerous on clay bluffs of cut banks and on rocky 

 slopes of buttes. 



57. CACTACEAE (Cactus Family) 



287 Maurillaria "di'ipara (Xutt) Haw. Pin-cushion Cactus. 

 Fairly frequent on the steppe especially on the moister por- 

 tions. 



288 Opuntia fragilis (Xutt.) Haw. Smaller Prickly Pear. 

 Abundant in blowout spots on hard pan, especially on flats 

 along valleys. 



289 Opuntia polyacantha Haw. Larger Prickly Pear. 

 Abundant on the steppe in general, but seldom in blowouts. 



58. ELAEAGXACEAE (Oleaster Family) 



290 Shcpherdia argent la Xutt. Buffalo Berry. 



Abundant in dense thickets along streams, in washouts, and 

 on hillsides. The yellow fruited variety is widespread but rare. 



