NEOMAMMILLARIA. 139 
or blackish at tip; spine-areoles when young densely white-woolly; fruit clavate, red, 10 to 18 mm. 
long; seeds black with basal hilum. 
Collected on Santa Cruz Island, Gulf of California, by J. N. Rose, April 16, 1911 
(No. 16842, type), and by Ivan M. Johnston in 1921 (No. 3912); also on the adjacent 
island of San Diego by Mr. Johnston (No. 3923). 
This is a very beautiful plant which grows in small clusters and is covered with nearly 
pure white spines. A number of plants were brought back to the New York Botanical 
Garden in 1911 by Dr. Rose but they have all since died. We now have living plants sent 
in by Mr. Johnston from two localities. 
Figure 152 is from a photograph of a plant sent by Mr. Johnston to Washington from 
the type locality. 
Fic 153-—Neomammillaria slevinii. 
103. Neomammillaria slevinii sp. nov. aa lectn 
Plants simple, cylindric, 1 dm. high or more, 5 to 6 cm. in diameter, entirely hi en under the 
many closely set spines: spines at top of plant pinkish below, with brown to blackish UPS, on 
lower part of plant bleaching white; radial spines numerous, acicular, widely sprea ngs centra 
spines about 6, a little longer and stouter than the radials, slightly spreading; owers al ou 2 cm. 
broad; outer perianth-segments with a pinkish mid-rib; inner perianth-segments white; Hlament 
pinkish; style nearly white; stigma-lobes nearly white; fruit red, about 1 cm. long; seeds , 
nearly globular, with a projection at base and a large basal hilum. 
Collected by J. N. Rose, March 31, 1911 (No. 16550, type), on San Josef Island, 
and by Ivan M. Johnston in 1921 (No. 3943) on San Francisco Island just off the south- 
ern end of San Josef Island. ; ; 
This Species is related to Neomammillaria albicans, but it has darker spines and the 
Spine-areoles are not densely lanate. —— _ . 
The plant is named for J. R. Slevin, who was in charge of the scientific expedition of the 
California Academy of Sciences to the Gulf of California in 1921, at which time the plant 
was collected. 
