26 UNITED STATES AND MEXICAN LOUNDARY. 
tomentosis ; aculeis omnibus robustis angulatis plus minus compressis albidis, radialibus 8-11 
rectis seu paullo curvatis, superioribus debilioribus, lateralibus robustioribus, infimo deficiente ; 
aculeis centralibus 4 validioribus, 3 rectiusculis sursum versis, infimo valido longiore curvato 
deflexo ; bacca sicca oblonga squamis aristatis spinescentibus tomentoque denso albo vestita floris 
rudimentis coronata. (Tab. XXXII, fig. 6-7.) 
Desert region southwest of El Paso towards Lake Guzman, over an area of 60 or 80 miles in 
extent, found by Parry with old fruit in January, and by Wright and Bigelow without flower or 
fruit in April.—I have before me only a few bunches of spines; the other data are all obtained 
from Dr. Parry’s notes. The plant is 8 or 12 inches high by 10 or 15 inches in diameter, always 
simple; the ribs interrupted; upper tubercles less distinct, flattened sidewise, lower older ones 
transverse and very distinct grooves between the ribs about an inch deep ; areole of the spines 
3 inch in diameter, orbicular, or with the closely adjoining floriferous ne oval, about } inch 
long. Radial spines in my specimen 8 or 9, “‘ often as many as 11;’’ lower ones divergent ; 
stoutest upper ones more slender. Central spines 4, stouter and 1-2 inches long, somewhat 
bulbous at base, upper and lower one, especially the last, stoutest and longest.—This species is 
nearly allied to the last, but even in the absence of seeds we can distinguish it by the simple 
globose or somewhat depressed heads, and the white spines. I have named it after Dr. C. C. 
Parry, who by his intelligent observations and copious notes about the Cactacee of the Boundary 
has greatly assisted me in their elucidation. 
14. E. nortzonTHALonius, Lemaire, var. cENTRISPINUS: glaucus, depresso-globosus (vetustus 
sepius ovatus umbilicatus) ; costis 8 obtusissimis latissimis; sinubus superficialibus acutis ; 
tuberculis sulco transverso inconspicuo vix distinctis ; areolis orbiculatis basi truncatis promi- 
nulis, junioribus albo-lanatis ; aculeis 6-8 robustis compressis annulatis recurvatis rubellis 
demum cinereis, radialibus 5-7, superioribus debilioribus, infimo deficiente, centrali singulo 
robustiore latiore deorsum flexo ; floribus ex vertice densissime lanato centralibus campanulatis ; 
ovario tuboque lana longa dense vestito ; sepalis exterioribus 60-70 subulatis linearibus et 
lanceolato-linearibus spinoso-aristatis atropurpureis nudis ex lana copiosissima axillari vix ex- 
sertis ; sepalis interioribus sub-15 obovato-lanceolatis mucronatis axilla nudis; petalis sub- 
36 oblongis obtusis eroso-dentatis roseo-purpurcis ; stylo supra stamina numerosissima flava 
exserto rubello ; stigmatibus 6-8 brevibus erecto-patulis ; bacca rubra succosa mox desiccata 
lana densa involuta floris rudimentis spinescentibus coronata a basi fere persistente circumscissa 
decidua ; seminibus subglobosis rugosis minutissime tuberculatis nigris opacis, hilo transverso 
ventrali ; embryone exalbuminoso suberecto clavato ; cotyledonibus brevissimis. (Tab. XX XI, 
Tab. XXXII, fig. 1-5.) 
Stony soil on the summit of hills, from the Pecos to El Paso, and north to Dofia Ana, Wislizenus, 
Wright, Bigelow, Parry: fl. April and May, and ‘‘ continuing to put out its beautiful flowers till 
July.’’—Easily distinguished by the broad obtuse ribs. The numerous specimens examined by 
me are all depressed, 14-4 inches high and 24-6 inches in diameter; but old specimens are 
said to be sometimes 6-8 inches high, oblong, and even cylindric ; ribs in very young speci- 
“mens 5, in all the flowering plants which I have seen, 8, and ‘‘sometimes 10’’; in young plants 
the ribs are scarcely interrupted, but in older ones they are divided by more or less shallow 
grooves into very broad tubercles ; areola 6-10 lines apart, covered with long wool when 
young ; spines mostly 6-8, rarely 9, $}-14 inch (and usually 1 inch) long, nearly equal in 
length, very variable in shape and thickness, sometimes long and slender and almost terete ; 
