182 CACTACEA OF THE BOUNDARY. 
paucisve munito (juniore spiny pattern ; axillis latis, junioribus dense tomentoso-lanatis ; areolis orbicu- [11] 
latis villosissimis demum nudatis ; aculeis 10-20 rectis seu subinde curvatis robustis rigidis basi bulbosis albidis 
seu citrinis apice ak radialibus ngs (3-5 inferioribus lateralibusque equilongis robustioribus compressis, 
7-11 superioribus debilioribus teretioribus), centralibus 1-5 validis angulatis paulo longioribus Ley is citrinis seu 
rubicundis, singulo validissimo porrecto ; floribus in vertice tomentosissimo laxis flavis; sepalis 16-22 lanceolatis, 
inferioribus ciliatis ; petalis 16-20 oblongo-lanceolatis versus apicem denticulatis mucronatis ; Freie 6-10 
bac iridi 
Sandy ridges in the valley of the Rio Grande, from El Paso to the Cafion ; also at Eagle Spring and on prairies 
at the nis of the Limpia : Charles Wright. Flowers in July. — A stately plant, by far the largest of the northern 
Mamillar Largest specimens before me 7 inches high, 5 inches in diameter without the spines. Tubercles loosely 
Sakae in ihe sealer specimens in 8, in the larger ones in 13 spiral rows, at base 7-1 inch in diameter, suddenly 
contracted and almost cylindric, 1-14 inch long and 5-7 lines in diameter, spreading, ascending ; tubercles on the 
lower part of plant shorter, more conic, and somewhat imbricated. Groove very deep, with 1-5 orbicular depressed or 
hemispherical warts or glands of nearly a line diameter. Central spines 10-18 lines long, mostly yellow ; lower radial 
about 9-15, upper 5-10 lines long, — when young mostly ps at base, paler in the middle, and dark purplish-black at 
tip, sometimes yellowish ; when eo all the spines become ashy-gray with dark tip. Flowers 2 inches long, yellow ; 
ovary 5-6 lines long. Young and small specimens have pall: tubercles, and about 6-8 radial spines 6-9 lines long, 
with a single straight or simi much stouter central one an inch long. 
. Scheerii, from Chihuahua, is distinguished from our plant, page| to aoe Sores description, by the 
shorter and fewer (5-11) radial spines, and the single “ much longer, 1 inch long,” central spine. It is globose, 
in diameter ; flowers of same size as ours, with apparently entire (?) sepals a eee yellow petals. 
The snr are described as naked, while in our plant we find the young ones very thickly covered with long 
wool, which disappears by age. Nevertheless, I consider ours only as a northern form of the Chihuahua species, with 
more numerous and stouter spines, which character very often distinguishes northern and southern varieties of one 
and the same species. 
3. M. ropustispina, A. Schott in litt.: robusta, simplex seu czespitosa ; tuberculis magnis patulis subteretibus 
sulcatis ; areolis magnis orbiculatis, junioribus dense tomentosis ; aculeis radialibus 12-15 robustis rigidis, inferioribus 
robustioribus obscurioribus rectis seu deorsum curvatis, Cada rectis es lager? paullo tenuioribus ; aculeo 
centrali singulo valido compresso deorsum recurvato, subinde altero superiore rectiore adjecto, aculeis omnibus corneis 
apice atratis subpollicaribus ; floribus e basi tuberculorum juniorum cel ator campanulatis luteis ; tubo supra 
ovarium ovatum constricto tenui, intus ad basin usque filamentoso ; sepalis lanceolatis, inferioribus ciliolatis; petalis 
numerosis ; stigmatibus 9-10 patulo-erectis ; bacca viridi ; seminibus gop oblique obovatis circa hilum parvum 
lineare etiile curvatis fuscis ; cotyledonibus distinctis foliaceis, (Tab. LX XIV. fig. 
On grassy prairies on the south side of the Babuquibari lane in Sonora ; i: Schott. Flowers July. — 
A large plant, cespitose, perhaps from the effects of prairie fires, as Mr. Schott suggests. Tubercles nearly an inch 
long, and about an inch distant from one another ; areola 34—4 lines in diameter. Spines 9-15 lines long, lower ones 
stouter but a little shorter than the upper ones, dock on the upper and lighter colored on the lower surface ; 
central spines 1 or sometimes 2, stouter but not much longer than the others ; base of lower or principal central [12] 
spine nearly 1 line wide. Flowers 1}~2 inches long, well characterized by the slender tube, which is contracted 
above the ovary, and quite similar in that respect to the flower of M. spherica (see above) ; petals “ saffron-yellow ;” 
filaments from the base of the tube, leaving no naked space above the ovary, as is the case in most species. Seeds 
1.5-1.6 line long, and fully a line in ata the largest of any Mamillaria examined by me ; albumen more distinct 
than usual in this genus; embryo curved, with somewhat foliaceous accumbent cotyledons, resembling much more 
the embryo of some Echinocactus than that of any Mamillaria known to me. The plant is evidently nearly allied to 
the foregoing, and also somewhat to the next species, but is distinguished by the very stout spines, and especially the 
slender and constricted tube of the flower. In M. Scheerii the filaments leave the lowest part of the tube free. 
14. M. RECURVISPINA, sp. nov.: simplex, globosa seu depresso-globosa ; tuberculis ovatis obtusis profunde 
sulcatis confertis subimbricatis ; write obliquis ovatis ; aculeis radialibus 12-20 basi bulbosa co mpressis rigidis 
recurvis flexnosisve albidis seu corneis apice sepe adustis intertextis; aculeo centrali singulo (inte terdum secundo 
superiore adjecto) robustiore longiore obscuriore decurvato seu raro rectiusculo ; floribus in axillis villosissimis 
tuberculorum juniorum sinedialiins majusculis flavicantibus extus fuscatis ; sepalis lanceolatis acutis integris ; 
petalis erosis. 
Eastern parts of Pimeria Alta, in Sonora, especially in the Sierra del Pajarito; A. Schott. Flowers June to 
August. — Heads single, mostly depressed, “4-8 inches in diameter” (a living specimen before me has only 3 inches); 
tubercles in my specimen in 13 spiral rows, 5-6 lines long, ovate, somewhat compressed from above ; areole very 
oblique, ovate, 2-24 lines long, white woolly when young. Radial spines in my living specimen 14-16, in a dried one 
