NEOMAMMILLARIA. 1 63 



Illustration: Emory, Mil. Reconn. 157. f. 2, as Mammillaria fasciculata. 

 Figure 180 is from a photograph of a plant collected by F. E. Lloyd near Tucson in 

 1906. 



145. Neomammillaria nelsonii sp. nov. 



Globose, 5 cm. in diameter; tubercles numerous, small, terete, apparently not milky, 5 to 7 

 mm. long, their axils naked; radial spines about 15, acicular, white, 6 to 8 mm. long, spreading; 

 central spines several, all like the radials; but one of them elongated, stouter and longer than the 

 others, brown to black, strongly hooked, 12 to 15 mm. long; flowers unknown; fruit very slender, 

 clavate, 3 cm. long or more, red, few-seeded; seeds globose, black, rugose, 2 mm. in diameter; hilum 

 basal, triangular, white, depressed. 



Collected by E. W. Nelson on cliffs at La Salada, Michoacan, Mexico, March 23, 

 1903 (No. 6932). 



This plant in its form and in the color and shape of the fruit agrees with Neomammil- 

 laria but differs from all the species we know in its rather large rugose black seeds. It some- 

 what resembles Neomammillaria zephyranthoides. 



Figure 182 shows the fruit, spine-cluster, and seed of the type. 



146. Neomammillaria longifiora sp. nov. 



Solitary or clustered, small, 3 cm. in diameter, apparently not at all milky; tubercles small, 

 terete, not grooved on upper side, 5 to 7 mm. long, rather closely set and nearly hidden by the spines ; 

 radial spines about 30, acicular, 10 to 13 mm. long, yellow or straw-colored, somewhat spreading; 

 central spines 4, reddish brown, much stouter than the radials, 3 of them straight, about length of 

 radials, i of them hooked at apex, twice as long as others; flowers several, even on small plants, 

 borne near top, 2 cm. long or more, with a distinct narrow tube; perianth-segments pinkish, oblong, 

 acute; ovary very small, ovoid, more or less sunken in the axils, thin above and perhaps opening 

 by an operculum, the lower part with the seeds persisting for years ; seed nearly globose, minutely 

 pitted, I to 1.5 mm. in diameter, black with a prominent white hilum. 



KiG. 182. — Fruit, spine-cluster, 

 and seed of N. nelsonii. 



-Seed and spine-cluster of 

 N. longifiora. 



Collected at Santiago Papasquiaro, Durango, by Dr. Edward Palmer in 1897 (No. 89). 



We have repeatedly studied this curious plant during the last 25 years, but have never 

 been able to identify it or reach a definite conclusion as to its relationship. Our material 

 consists of a single plant split down one side, bearing several withered flowers, and two 

 detached flowers. Recently, we were sent a photograph of a cactus from Mexico, labeled 

 Mammillaria n. sp.. Sierra de Cacaria S. de Ulama, which seemed to be Dr. Palmer's plant 

 and led us to make a detailed study of it. One of the peculiarities was the absence of 

 an exserted ovary, so conspicuous in all the Neomammillaria. The cut stem showed an 

 exposed sunken ovary, and by mere chance an old fruit with ripe seeds, probably several 

 years old, was found in the axils of one of the oldest tubercles. As described above, the 

 seeds are very unlike those of any species of Neomammillaria. 



