NEOMAMMILLARIA. 137 
More or less cespitose, the individual plants cylindric, 12 cm. long or more; tubercles almost 
hidden by the spines; radial spines about 30, white, weak, short; central spines 6 to 12, much stouter 
and longer, more or less ascending, grayish with brown tips; axils of tubercles woolly ; flowers borne 
in a circle about 2 cm. below top of plant, about 1 cm. long; inner perianth-segments light purple, 
somewhat spreading at tip, acute; stamens pale, much shorter than the style, purplish above; 
stigma-lobes narrow; fruit red, clavate; seeds blackish brown, the surface deeply pitted. 
Type locality: Not cited. 
Distribution: In the highlands of the Rio Grande, Texas; Nuevo Le6n and Coahuila 
to Chihuahua and Zacatecas, Mexico. 
This species is widely grown in collections but the flowers are inconspicuous. 
In the Engelmann Collection, now in the Missouri Botanical Garden, is a specimen 
labeled “‘Mammillaria pottsii vera—original coll. Dyck. Jan. 1857.’’ This proves to be 
identical with the plant well known in our collections as M. leona. With specimens of this 
plant in hand Salm-Dyck’s description, which heretofore we had not understood, is clearly 
Fic. 151.—N. mazatlanensis. 
Fic. 150.—Neomammnillaria pottsii. 
interpreted, except that he states that the tubercle is slightly sulcate above. From the fact 
that Engelmann says that his specimen is ‘‘M. pottsii vera”’ we suspect that he may have 
had a plant like MW. tuberculosa mixed with it. This seems to have been Poselger’s idea, for 
he refers the plant to Echinocactus, doubtless on account of this supposed groove. The plant 
which Poselger describes under Echinocactus pottsianus, collected at Guerrero, south of the 
Rio Grande, is very different from Salm-Dyck’s plant; his fragment, also deposited in 
the Missouri Botanical Garden, consists of a fruit, a few brownish seeds, anda spine-cluster, 
one attached to the top of a grooved tubercle, and is to be referred to Escoba ria tubercul osa, 
or a related species. The specimen is too fragmentary to identify definitely. Poselger's 
misunderstanding of Salm-Dyck’s plant left the way open for his species, Mammullaria 
leona, described shortly afterwards. ; ken f 
The description of the flower and fruit as given by Coulter 1s doubtless ta cen rom 
Poselger but does not apply to the true M. pottsii. Our only Texas record is based on J. 
H. Ferriss’s plant from the Big Bend of the Rio Grande, November 15, 1922. ened 
Coryphantha pottsii occurs in C. R. Orcutt’s Circular to Cactus Fanciers 1922 (unsigne 
and undated) to which he assigns M. leona. 
