PLANT FENDLERIAN. 49 
CACTACEA. (By Dr. Engelmann.) 
244, Mammitntaria vivipara, Nutt. sub Cacto. Common from Bent’s Fort to 
Santa Fé, on rocky hills and elevated plains; flowering in July. — “‘ Heads mostly single, 
often in pairs, rarely ceespitose from the ramifications of the subterraneous stem”; not 
proliferous, as some specimens from the Upper Missouri are. — ‘There can be little 
doubt that this is the true Cactus viviparus of Nuttall, although the flowers do not appear 
to be entirely central. I have living specimens from Santa Fé, and from the Upper Mis- 
souri, and shall be able to decide their identity after having seen them flowering. — 
I possess, also, a living specimen of Nuttall’s Cactus mammillaris (Gen. p. 295), and 
have observed its flower and fruit. It is, as has been long suspected, entirely different 
from the West Indian Mammillaria simplex, DC., and is nearly related to M. similis, 
Engelm. in Pl. Lindh. I have named it after its discoverer.* 
245, M. pAPYRACANTHA (sp. nov.): ovata, prolifera, aculeis omnibus planis charta- 
ceis flexilibus albis, radialibus brevibus 8 centralibus 3 — 4 multo longioribus, 2 - 3 supe- 
rioribus sursum curvatis, singulo inferiore longiore latiore deorsum flexo; floribus centra- 
libus (albidis) ; sepalis 12-16 ovatis acutis integris; petalis sub-13 lanceolatis acumina- 
tis integris; stigmatibus 5 suberectis exsertis albidis. — In a valley between the lower 
hills, near Santa Fé, in loose, red sandy, though fertile soil: found only once ; flowering 
in May. — About 2 inches high, and 13 inch in diameter; the tubercles in about 8 spiral 
rows; lower ones proliferous ; their shape not well distinguishable in the half-rotten spe- 
cimen before me. Spines silky-white, shining, of the consistency of stiff paper. None 
of the 8 radiating spines (13 or 2 lines Jong) are directed upwards, but all laterally or 
* M. Nurratuu (sp. nov.): simplex (an semper ?), globosa, axillis tuberculorum ovato-cylindricorum 
supra leviter sulcatorum subtomentosis; areolis junioribus albo-tomentosis; aculeis rectis albidis, radialibus 
13-16 subinequalibus setaceis, centrali porrecto robustiore ; floribus ex axillis tuberculorum hornotinorum 
centralibus (ex rubello flavicantibus) ; sepalis petalisque oblongo-lanceolatis ; sepalis 10 -— 13, brevioribus exte- 
rioribus ciliato-fimbriatis obtusiusculis, interioribus apice laceris acutis ; petalis 20 — 23 integris breviter abrupte 
mucronatis ; stylo supra stamina (rubella) paulo exserto, stigmatibus circa 5 brevissimis erectis adpressis viri- 
dibus ; baccis lateralibus subglobosis coccineis. Cactus mammillaris, Nuét., non Linn. — On high, dry prairies, 
about Fort Pierre, on the Upper Missouri; flowering in May. — My specimen is an inch and a half high, and 
of the same diameter; the tubercles 6 or 7 lines long, in 8 spiral rows, slightly suleate. Radial spines 4 or 
5y the central one 5 to 6 lines long; the young spines at the apex slightly brownish. Flowers an inch long, 
and, when fully expanded, of the same diameter. Petals about 2 lines wide, acute, abruptly mucronate. 
Stigmas only from one half to three fourths of a line long, erect. The fruit ripens the following spring, and, 
as well as the seed, is very similar to that of M. similis, but only half as large, although the pits of the globose 
black seed are of the same size. 
