STAXDLEY TREES AND SHEUBS OF MEXICO. 927 



Cespitose, nearly globose, glaucous-green; ribs 10 to 12, somewhat tubercu- 

 late; areoles circular; radial spines 7 to 10, slender, needle-like, 12 to 18 mm. 

 long, spreading; central spine one, stouter tlian the radials, the central as 

 well as the radials pale brown but reddish at base when young ; inner perianth 

 segments spatulate, acute, somewhat serrate toward the tip, glossy above, pur- 

 ple, whitish at base; ovary and fruit spiny. 



31. Echinocereus knippelianus Liebner, Monatsschr. Kakteenk. 5: 170. 1895. 

 Echinocereus liehnerianus Carp. Bait. Cact. Journ. 2: 262. 1896. 

 Echinocereus Inerinis Haage, Monatsschr. Kakteenk. 8: 130. 1898. 



Cereus knippelianus Orcutt, West. Amer. Sci. 13: 27. 1902. 



Native of Mexico, but range not known. 



At first simple, stout, a little higher than broad, about 10 cm. high, but 

 in cultivation elongate, 20 cm. high or more, branching, very deep green, 

 becoming turgid and flabby; ribs 5 to 7, more prominent toward the top 

 of the plant, sometimes strongly tuberculate, at other times only slightly 

 sinuate ; areoles minute, white-felted, 5 to 6 mm. apart ; spines 1 to 3, weak, 3 

 to 6 mm. long, yellow; flowers pinkish, 2.5 to 3 cm. long; perianth segments 

 spreading, oblanceolate, acute; fruit not known. 



32. Echinocereus pulchellus (Mart.) Schum. in Engl. & Prantl, Pflanzenfam. 



3'": 185. 1894. 



Echinocactus pulchellus Mart. Nov. Act. Nat. Cur. 16: 342. 1828. 



Cereus pulchellus Pfeiff. Enum. Cact. 74. 1837. 



Probably in central Mexico ; type said to have come from Pachuca, Hidalgo. 



Stems obovate-cylindric, 5 to 7 cm. high, simple, glaucous; ribs 12, obtuse, 

 more or less divided into tubercles; spines 3 to 5, short, straight, deciduous, 

 yellowish ; flowers rosy white, about 4 cm. broad ; inner perianth segments 

 lanceolate, acuminate. 



33. Echinocereus anioenus (Dietr.) Schum. in Engl. & Prantl, Pflanzenfam. 



3'": 185. 1894. 



Echinopsis amoena Dietr. Allg. Gartenz. 12: 187. 1844. 



Cereus amoenus Hemsl. Biol. Centr. Amer. Bot. 1: 540. 1880. 



San Luis Potosl. 



Plants low, almost buried in the ground; ribs usually 13, low, somewhat 

 tuberculate ; young areoles bearing 6 to 8 rather stout short spreading spines ; 

 old areoles spineless ; flowers about 5 cm. broad, magenta ; inner perianth 

 segments spatulate, with an ovate acute tip ; areoles of the ovary and flower 

 tube bearing brown spines and cobwebby wool. 



34. Echinocereus palmeri Britt. & Rose, Cactaceae 3: 34. 1922. 

 Type from the City of Chihuahua. 



Plants 5 to 8 cm. high. 2 to 3 cm. in diameter ; areoles closely set, round ; 

 radial spines 12 to 15, spreading, slender, brown-tipped ; central spine one, 

 porrect, 1.5 to 2 cm. long, brown to blackish ; flower 3.5 cm. long, purple ; 

 areoles on the ovary bearing a cluster of brown spines and white wool. 



35. Echinocereus brandegeei (Coulter) Schum. Gesamtb. Kakt. 290. 1898. 

 Cereus hrandegeei Coulter, Contr. TJ. S. Nat. Herb. 3: 389. 1896. 

 Cereus sanborgianus Coulter, Contr. U. S. Nat. Herb. 3: 391. 1896. 

 Southern Baja California ; type from Campo Alem^n. 



Always growing in clumps ; joints sometimes one meter long or more, 5 cm. 

 in diameter, but usually much narrowed toward the base; ribs strongly 

 tubercled ; areoles circular ; spines at first light yellow tinged with red, in age 



