CACTUS FAMILY 549 



4. MAMMILLARIA Haw. 



Plants small, globose or short-cylindrical, simple or few-branched. Spines 

 straight or hooked, produced from areoles at the apex of mammilliform tubercles, 

 which are ungrooved and spirally disposed. Flowers solitary, funnelform or 

 campanulate, red, pink, yellowish or white, borne from the axils of mature tu- 

 bercles, therefore below the summit of the stem. Fruit a elavate scarlet berry, 

 destitute of scales. Seeds black or brown, with or without an appendage. — Species 

 about 200, North and South America and the West Indies. (Latin mammila, 

 referring to the nipple-like tubercles. ) 



Most species are very local in their distribution. Many are in cultivation for their odd 

 appearance or the beauty of their flowers. Those having hooked spines are called "Fish-hook 

 Cactuses" and those with straight spines, "Pincushion Cactuses". The fruits are often called 

 "Desert Strawberries", and while small they are edible and agreeably acid. 



Seeds immersed in a corky appendage. — Subgenus Phellosperma 1. M. tetrancistra. 



Seeds destitute of an appendage. — Subgenus Exjmammillaria. 



Floral segments yellowish 2. M. dioica. 



Floral segments white 3. M. incerta. 



1. M. tetrancistra Engelm. Yaqui Cactus. Stems oblong, 4 to 10 inches 

 high, usually simple; tubercles with crisped wool in the axils when young, becom- 

 ing naked; central spines 1 to 4, acicular, about 1 inch long, dark purple nearly to 

 the white base, one or all hooked; radials numerous, straight, unequal, white, 

 shorter and slenderer than the centrals, radiate and concealing the surface; flowers 

 purple, 1 inch long, the outer segments ciliate; fruit elavate, bright red, % to 1 

 inch long; seeds black, minutely tuberculate, immersed at base in an ash-colored 

 cupulate appendage. 



Gravelly or stony benches or slopes, -200 to 2000 feet : Colorado and Mohave 

 deserts; Inyo Co. East to western Nevada. Infrequent ; solitary or distant. Apr. 



Locs. — Yaqui Well (Ironwood Well), e. San Diego Co., T. Brandegee; Andreas Canon, Palm 

 Sprs. of San Jacinto, Muns 5016; Whitewater, Parish; Cottonwood Spr., n. of Mecca, Evermann; 

 Death Valley, Parish. 



Refs. — Mammillaeia tetrancistra Engelm. Am. Jour. Sci. ser. 2, 14:337 (1852), type loc. 

 "from San Diego to the junction of the Gila [River] with the Colorado," Parry; Parish in Jepson, 

 Man. 659 (1925). M. phellosperma Engelm. Proc. Am. Acad. 3:262 (1856). Cactus tetran- 

 cistrus Coult. Contrib. U. S. Nat. Herb. 3:104 (1894). Phellosperma tetrancistra Britt. & Eose, 

 Cact. 4:60 (1923). 



2. M. dioica K. Bdg. Wreath Cactus. Stems frequently branched from 

 the base and rarely above it, globose to short-cylindrical, 2 to 10 inches high; axils 

 of the young tubercles containing wool and 4 to 15 short bristles; central spines 

 1 to 4, brown, acicular, the lowest, when more than one, stouter than the others, 

 about 14 inch long, upwardly hooked; radials 10 to 20, white, slender, about % 

 inch long, radiate and concealing the surface; flowers incompletely dioecious, yel- 

 lowish, with purplish midrib, 1 inch high; fruit 1/2 to 1 inch long; seeds black, 

 minutely pitted. 



Sandy soil, 1 to 500 feet : about San Diego. Southward along the coast of 

 Lower California. Often abundant. 



Locs.— Mt. Soledad, False Bay and Paradise Valley, ace. Ethel B. Biggins; mouth of Sweet- 



Eefs.— Mahmilla'ria "dioica K. Bdg. Erythea 5:115 (1897), type loc. "from San Diego a 

 short distance north, but southward to Cape St. Lucas"; Parish in Jepson, Man. 660 (1925). 



3. M. incerta Parish sp. n. Stems short-cylindrical, simple or few-branched 

 at the base, 3 to 4 inches high ; lower central spine purple, hooked, % inch long, 

 a little exceeding the one or two straight ones; radials 12 to 15, bristle-like, nearly 

 equal, about I/2 inch long; flowers campanulate, 1/2 to % inch long, white, each 

 petal marked on the back by a reddish-brown medial stripe; fruit obovate to ela- 

 vate, 1/2 to 1 inch long; seeds minutely punctate.— (Caules cylindrici, breves. 



