20 THE CACTACEAE. 



This species was probably first collected by Seemann in the Sierra Madre of Mexico, 

 where it was collected by Dr. Rose in 1897. It has frequently been introduced into culti- 

 vation but does not do well, soon dying out. It is able to stand considerable cold and in 

 its home is usually covered with snow during the winter. 



Salm-Dyck gave two varieties without descriptions, based on two unpublished names, 

 when he first listed Mammillaria senilis, as follows : M. senilis haseloffii (Salm-Dyck, Cact. 

 Hort. Dyck. 1849. 8. 1850; M. haseloffii Ehrenberg, AUg. Gartenz. 17: 303. 1849) and M. 

 senilis linkei (Salm-Dyck, Cact. Hort. Dyck. 1849. 8. 1850; M. linkei Ehrenberg). The 

 former, however, was published the pre^dous year as M. haseloffii and has priority. 



Illustrations: Fl. Serr. 21: pi. 2159; Rev. Hort. iv. 2: pi. 334; Belg. Hort. 24: pi. 3; 

 Cact. Journ. i : pi. for March; Contr. U. S. Nat. Herb. 5: pi. 62 ; Schelle, Handb. Kakteenk. 

 245. f. 163; Tribune Hort. 4: pi. 140; De Laet, Cat. Gen. 28. f. 41; Gartenwelt 14: 331; 

 Mollers Deutsche Gart. Zeit. 25: 475. f. 8, No. 31 ; Succulenta 4: 80, as Mammillaria senilis. 



Figure 19 is from a photograph of a flowering plant; figure 20 is from a photograph 

 of two flowers of a plant obtained in the Sierra Madre, Mexico, by I. Ochoterena in 191 1 ; 

 figure 21 is reproduced from the third illustration cited above. 



Fig. 21. — Matnillopsis senilis. 



2. Mamillopsis diguetii (Weber). 



Mammillaria senilis diguetii Weber, Bull. Mus. Hist. Nat. Paris lo: 383. 1904. 



Plants densely cespitose, forming a hemispheric clump of about 35 globular heads, each 25 

 cm. in diameter; radial spines numerous, dark straw-colored; flowers 3 cm. long, about 2 cm. broad, 

 deep red; ovary bearing small scales. 



Type locality: Sierra de Nayarit, Jalisco. 



Distribution: Jalisco to Sinaloa, Mexico. 



This species, until recently, was known only from the single collection of L. Diguet 

 made in March 1900; he found it in the mountains of Jalisco at an altitude of 2,500 meters. 

 It has again been collected by J. G. Ortega in the Sierra de Chabarra, Concordia, Sinaloa, 

 in 1 92 1. 



The type is in the Museum of Natural History of Paris and was studied there by Dr. 

 Rose in May 1912 ; he beHeves that it is distinct from M. senilis, the spines being of a dif- 

 ferent color and much more rigid than in that species. 



