I2O 



THE CACTACEAE. 



Stems low, growing in clumps, either prostrate or erect, sometimes 12 dm. high; joints broadly 

 obovate, 8 to 20 cm. long, slightly pubescent or glabrous, usually highly colored; leaves 2 to 5 mm. 

 long, subulate; areoles numerous, filled with white to brown wool and brownish glochids; spines none 

 or rarely a few at upper areoles; flowers large, 6 to 8 cm. long, deep purple or sometimes white; 

 filaments purple; fruit dry, globular to obovoid; seeds large, thick, 6 to 10 mm. broad. 



Type locality: From Cactus Pass down the valley of the Bill Williams River. 



Distribution: Northern Sonora, western Arizona, southern California, Nevada, and 

 southern Utah. 



This is a variable species as to habit, size, pubescence, and color of flowers. The 

 variety ramosa described by Mr. Parish is more erect than the ordinary form and glabrous. 

 It has large, handsome flowers, and is a splendid plant for outdoor cultivation where the 

 climate is suitable, but does not live long in greenhouses. It is called beaver-tail in 

 Arizona. 



Opimtia hnmistrata Griffiths (Bull. Torr. Club 43: 83. 1916) we refer here from the 

 description; it is said to differ from 0. basilaris "by its much smaller as well as different 

 shaped joints"; it was found in the San 

 Bernardino Mountains, northern California, 

 within the range of 0. basilaris. 



The following varieties are listed, but 

 have not been described: albiflora, cocntlca, 

 nana, and pfersdorffii. 



Opuntia basilaris cordata is a garden plant 

 briefly described by F. Forbes (Monatsschr. 

 Kakteenk. 16: 46. 1906), of which we have 

 seen no specimens. 



Illustrations: Cact. Journ. i: 167; Diet. 

 Gard. Nicholson 2: f. 750; Forster, Handb. 

 Cact. ed. 2. f. 129; Pac. R. Rep. 4: pi. 13, f. i 

 to 5 ; pi. 23, f. 14; Riimpler, Sukkulenten f . 123; 

 W.Watson, Cact. Cult. f. 76; Cact. Journ. i: 

 pi. October, as Opnntia basilaris var. cristata 

 and var. iic'caJciisis; Alverson, Cact. Cat. 

 frontispiece, as Opnntia basilaris albiflora. 



Figure 149 is copied from Pac. R. Rep. 4: pi. 13, f. i, an illustration cited above. 



Opnntia brachyclada Griffiths (Proc. Biol. Soc. Washington 27: 25. 1914) is an anom- 

 alous plant with some of the joints terete and others somewhat flattened. It has been 

 suggested that it is a hybrid between a cylindric and a flat-jointed species ; but, so far as 

 we know, natural hybrids do not occur between species of these subgenera. It is more 

 likely to be an anomalous form of Opnntia basilaris, a form of which is known in the same 

 mountains where it was found. 



110. Opuntia microdasys (Lehmann) Pfeiffer, Enum. Cact. 154. 1837. 



Cucltis micrndusys Lehmann. Ind. Sem. Hamburg. 16. 1827. 



Opuntia pulvinaia De Candolle, Mem. Mus. Hist. Nat. Paris 17: ng. 1828. 



Opniiliii iiiii-rada.'.ys minor Salm-Dyck, Hort. Dyck. 186. 1834. 



Opitntia microdasys laevior Salm-Dyck, Cact. Hort. Dyck. 1849. 241. 1850. 



Often low and creeping but sometimes nearly erect and 4 to 6 dm. high; joints oblong to orbicu- 

 lar, 10 to 15 cm. long, soft-velvety, usually pale green, spineless; areoles conspicuous, closely set, 

 filled with numerous yellow or brown glochids; flowers usually produced in abundance, 4 to 5 cm. 

 long, pure yellow or tinged with red; sepals acuminate; petals broad, retuse; filaments and style 

 white; stigma-lobes 6 to 8, green; fruit dark red, juicy, nearly globular; seeds small, 2 to 3 mm. broad. 



Type locality: In Mexico, but originally stated by Lehmann as coming from Brazil. 

 Distribution: Northern Mexico. 



FIG. 149. Opuntia basilaris. 



