Dr. Engelmann on the Cereus giganteus of California. 339 
10. O. ramostssmma, n. sp.: caule erecto ligneo divaricato-ra- 
mosissimo ;- articulis gracilibus cylindricis tuberculatis cesiis; 
" aculeis subsolitariis saccato-vaginatis ; bacca sicca tuberculata se- 
tosa et aculeata. of 
Gravelly soil near the Colorado, and in the desert. Plant two 
feet high; the joints half an inch in diameter. Approaches the 
Opuntia cylindracee graciliores. 
Parryi, n. sp.: caule prostrato; articulis adscendenti- 
bus tuberculatis; setis fuscis; aculeis brevibus albidis, singulo 
longiore deflexo ; bacca subglobosa, setoso-aculeata. 
Kastern slope of the California. mountains, near San Felipe. 
Joints four to eight inches long; the longest spines half an inch 
long. Flower one and a half inch in diameter, yellowish-green. 
Approaches the Opuntiz clavate. 
Mr. Charles Wright, well knéwn to the botanical world by his 
collections made in the southwest, now also attached to the Mex- 
lean boundary commission, has, under the instruction of Col. 
Graham, made large and interesting collections of Cacti in west- 
fra Texas and southern New Mexico, and sent them to me for 
examination. - 
tis impossible here to give as full an account of them as 
Wwanld be desirable; but most of them are now in cultivation 
and will be described hereafter. Most of the Cactacee discov- 
