CACTACEX. 17 
levibus fulvis, hilo oblongo-lineari ventricali ; albumine parco ; embryone recto ; cotyledonibus 
minutis. (Tab. XIV-XV.) 
In the valley of the Rio Grande, from Dojia Ana, above El Paso, Wislizenus, to the cation 
below that town, Wright, and to the mouth of the Pecos and to Eagle Pass, Bigelow, and lower 
down, mostly in loose sand, on hillocks confined by the roots of Algarobia: fl. July and August.— 
A splendid and very interesting species, 2-4 inches high ; tubercles very different in size in dif- 
ferent specimens, from 6 or 7 to 10 or 12, and*sometimes even 15 lines long, generally arranged 
in 8 spirals. The groove is absent in the tubercles of the young plant; in the older ones it 
shows itself slightly, and only near the point of the tubercle, from the spine downwards ; in 
more fully developed tubercles it becomes longer, till in the flower-bearing ones it reaches 
downward to the lower third, but never to the axilla; there it enlarges into the flower-bearing 
areola.—Radial spines 6-20 lines long, whitish or the upper ones or all rose-colored when 
young; central spines 1-2} inches long, the lowest.one longer and stouter than the rest, mostly 
black, in some specimens paler, straight, or sometimes curved or twisted. Flower 24-3 inches 
long, and of the same diameter, deep rose-color or carmine verging to purple, darker along 
the centre and towards the tip. Fruit 8 to 10 or 12 lines long ; seeds different in size, 0.7-0.8 
line long, short and thick, with a decidedly ventral hilum. Albumen distinct, more so than in 
‘most other Mamillarie, but the embryo quite similar to them. The scales on the ovarium indi- 
cate an approach to Echinocactus, though the habit of the plant is decidedly that of a Mamil- 
laria.—M. dactylothele, Lab. is a variety of this species. 
Subgen 3. ANHALONIUM. 
Plante simplices, tuberculate, subinermes, 
Tubercula subfoliacea, triangularia, levia seu supra verrucoso-fissurata, 
Areole floriferee supra-axillares (an semper ?), Kiger 
Flores ex areolis tuberculorum h ti riundi, in vertice congesti, mediocres. 
Ovarium emersum: bacca floris rudimentis dototiata; eilevatiiide anno primo maturescens. 
Semina majuscula, nigra, tuberculata. 
These very curious plants, some of them looking more like some dloé than like a Cactus, can 
nevertheless not be separated from Mamillaria. The seed is the only part of the organs of fruc- 
tification which seems to offer any character, by having a hard, roughly tuberculated testa in 
ours as well as in another Mexican species which I had the opportunity toexamine. Our species 
(and probably all the others) has the flower and fruit sessile upon the lower part of the tubercle ; 
and elevated above the axil, much as in M. macromeris; but, unlike that plant, the lower part of 
the tubercle is entirely distinct from the upper one. 
23. M. FissuraTA (sp. nov.): e radice crassa napiformi simplex, depresso-globosa seu appla- 
nata; vertice densissime villoso ; tuberculis e basi applanta dilatata crassis triangularibus iner- 
mibus extus infraque levibus seu versus marginem crenulatum rugosis, supra sulco centrali 
villoso lateralibusque 2 nudis profunde quadripartitis et sulcis transversalibus in tubercula irre- 
gularia angulosa numerosa multifidis ; floribus e villo longo sericeo centralibus breviter tubulosis ; 
sepalis sub-20, inferioribus lineari-lanceolatis integris carnosis albidis, superioribus spathu- 
latis cuspidatis ; petalis sub-12 spathulatis versus apicem obtusum mucronatum integriusculis 
seu laceris roseis ; sti pee a 5-10 erecto-patulis; baccis ovatis pallide virescentibus in lana 
