20 
THE CACTACEAE. 
More or less cespitose, rather dark green, decumbent or ascending, 5 to 30 cm. long, 2 to 4 cm. in 
diameter; ribs 6 to 10, prominent, strongly tubercled; radial spines acicular, spreading, about 7, 
white to yellowish, 1 cm. long or less; central spine solitary, acicular, porrect, 12 mm. long or more; 
flowers large, 10 to 12 cm. broad, yellow with a reddish center, with rather few perianth-segments 
4 to 6 cm. long, oblong-spatulate, acuminate, more or less serrate; scales on ovary red, spreading; 
fruit not known. 
Type locality: Not cited. 
Distribution: Western Texas. 
Although this species is supposed to come from the vicinity of San Antonio, Texas, no 
specimens are known to us from that place but we have an herbarium specimen collected by 
Miss Mary B. Croft at San Diego, Texas. It is one of the few species in the genus with 
yellow flowers and ought easily to be distinguished from other Texan species. 
Illustration: Bliihende Kakteen 2: pi. 115. 
Fig. 20. —Echinocereus ctenoides. Fig. 20 a .—Echinocereus pentalophus. 
26 . Echinocereus blanckii* (Poselger) Palmer, Rev. Hort. 36:92. 1S65. 
Cereus blanckii Poselger, Allg. Gartenz. 21: 134. 1853. 
Cereus berlandieri Engelmann, Proc. Amer. Acad. 3: 286. 1856. 
Echinocereus poselgerianus Linke, Allg. Gartenz. 25: 239. 1857. 
Echinocereus berlandieri Riimpler in Forster, Handb. Cact. ed. 2. 776. 1885. 
Echinocereus leonensis Mathsson, Monatsschr. Kakteenk. 1: 66. 1891. 
Cereus leonensis Orcutt, West Amer. Sci. 13: 27. 1902. 
Cereus poselgerianus Berger, Rep. Mo. Bot. Gard. 16: 80. 1905. 
*The specific name is often spelled blankii. 
