to the Rocky Mountains. 223 



CONVOLVULACEjE. 



284. Convolvulus. Several species were collected in 

 the barren deserts of the Platte, and about the sources of the 

 Canadian, but the specimens were so imperfect that it was im- 

 possible to determine them. Dr. James states that he observed 

 an annual lactescent species, with a flower as large as that of 

 Stramonium. 



2S5. Evolvulus Nuttallianus, Roem. and Schult. syst. 

 vi. p. 198. E. sericeus, Nutt. gen. i. p. 375. About the 

 forks of the Platte : found also in Florida, by the late Dr. 

 Baldwin. 



286. Diapensia. earbulata, Ell. fl. i. p. 229. Dia- 

 pensia barbulata, Michx. fl. i. p. 152. Gravelly plains along 

 the Platte. Dr. James. 



Obs. There were no specimens of this plant in the collec- 

 tion. I suspect there is some mistake in assigning it a sta- 

 tion so far to the west : in the Atlantic states it is almost ex- 

 clusively found in sandy pine woods. 



287. Cuscuta umbellata, Kunth syn. ii. p. 232. 

 Very abundant about the sources of the Canadian ; parasitic 

 on Portulaca oleracea. 



HYDROLEACE^. 



288. Hydrolea spinosa, L. Willd. sp. pi. i. p. 1327. 

 Kunth syn. ii. 234. On the Canadian ? 



Obs. This differs somewhat from the description of Kunth, 

 in having ovate-oblong, instead of lanceolate leaves. Mr. 

 Nuttall considers it a distinct species. 



Vol. II. 27 



