ii6 



THE CACTACEAE. 



Dr. Rose collected living specimens from the type locality some years ago but these 

 never flowered. In April 192 1 we sent Dr. Reiche to the type locality and he obtained 

 thirteen beautiful specimens, one of which was in fruit. 



Coulter (Contr. U. S. Nat. Herb. 3: 109. 1894) states that Cactus pringlei was near 

 Cactus rhodanthus sulphureospinus, which was based on M. sulphurea Forster. 



Figure 121 is from a photograph of the plants collected at Tultenango Canyon in 192 1. 



73. Neomammillaria cerralboa sp. nov. 



Cylindric, solitary, i to 1.5 dm. high, 5 to 6 cm. in diameter; 

 tubercles not milky, yellowish, terete, obtuse, closely set; spines 

 all yellow, very much alike, about 11, one usually more central, 

 the longer ones nearly 2 cm. long; flowers small, i cm. long or 

 less, forming a circle around the plant about 3 cm. below the top. 



Collected by Ivan M. Johnston on Cerralbo Island, 

 Gulf of California, June 6, 192 1 (No. 4038) . The next day 

 on the same island he collected three more plants (No. 

 4053) which seem to be referable here, except that two of 

 them have hooked spines ; Dr. Rose also collected on this 

 same island (No. 16877) in 191 1 specimens with hooked 

 spines which are like Mr. Johnston's plant. Whether this 

 plant has normally these two forms or whether the hooked- 

 spined one is a hybrid we are unable to determine. 



Figure 121a is a photograph of the type plant, col- 

 lected by Johnston (No. 4038). 



74. Neomammillaria phaeacantha (Lemaire). 



Manimillaria phaeacantha Lemaire, Cact. Gen, Nov. Sp. 47. 



1839. KiG. 121a. 



Mammillaria nigricans Fennel, Allg. Gartenz. 15: 66. 1847. 

 Cactus nigricans Kuntze, Rev. Gen. PI. i: 261. 1891. Not Haworth, 1803 

 Cactus phaeacanthus Kuntze, Rev. Gen. PI. i : 261. 1891. 



Neomammillaria cerralboa. 



/.T!»StelHSS»»F 



Fig. 122. — Neomammillaria phaeacantha. 



Fig. 123. — Neomammillaria graessneriana. 



Globose or somewhat depressed, green ; axils of tubercles woolly ; tubercles conic, hardly, if at 

 all, angled; spine-areoles small, yellowish tomentose (probably so only when young); radial spines 



