150 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 13 



which Johnston referred to F. alamosanus, apparently, Proc. Calif. Acad. 

 Sci. 13:1110. 1924. Although the present collection, the species, and its 

 variety appear to be related, further field work and study may reveal 

 that we are dealing with three specific entities. 



Lemaireocereus Thurberi (Engelm.) Brit. & Rose, C.N.H. 12: 

 426. 1909. 



South end of Tiburon Island, March 27, Rempel 297. San Pedro 

 Nolasco Island, March 29, Rempel 305. Ensenada de San Francisco, 

 Sonora, Rempel 312a. Frailes Bay, Re?npel 322. 



The pitaya (traditionally spelled pitahaya, but poorly so from the 

 phonetic standpoint) is widely distributed in the central and southern 

 part of the California Gulf Region; from southern Arizona to central 

 Sinaloa. In central Baja California it favors the rocky slopes where run- 

 off increases soil moisture. In southern Sonora, the area of greatest 

 abundance, it is found both on rocky slopes and alluvial plains, as on the 

 plain south of Navojoa, where it abounds in dense nearly pure stands 

 over many square miles. Flowers in late spring, fruits ripen in late May 

 and June. All the above collections are sterile. 



Lemaireocereus Thurberi littoralis (K. Brge.) G. Lindsay, 

 Desert PI. Life 12:186. 1940. 



Cereus Thurberi Engelm. var. littoralis K. Brge., Zoe 5:191. 1904. 



Canyon above Puerto Escondido, March 13, Rempel 145 (imma- 

 ture). Fraile Bay, April 4, Rempel 326. 



Cape District and north along the Sierra Giganta scarp to Con- 

 cepcion Bay; type from "on steep seacoast bluffs between San Jose del 

 Cabo and Cabo San Lucas, Baja California." This low slender plant 

 appears to be a good variety. The collections show only 6 to 7 ribs and 

 weaker spines than is typical of the species. Rempel 209 from an island 

 in Concepcion Bay is probably also referrable here. All specimens are 

 sterile. 



LoPHOCEREUs ScHOTTii (Engelm.) Brit. & Rose, C.N.H. 12:427. 

 1919. 



Los Angeles Bay, Baja California, March 19, 20, Rempel 232, ir^ 

 wash and on fan. Fraile Bay, April 4, Rempel 324. 



Widely distributed in the gulf area; type from Magdalena, Sonora. 

 A widely spreading plant commonly 2 to 3 m tall with many stems from 

 the decumbently spreading base, recognizable by the sordid "beard" of 

 long bristles of the terminal 1 to 3 feet of the flowering branches. 



