x. 
27 
with bunches of spines which, as in the last species,’ on the flower are 
indicated only by few and short bristles. Seed with tubercles conflu- 
ent, and leaving pits between them. Nearly allied to the two last, 
but sufficiently well distinguished by the characters given. 
15. C. ENGELMANNI, Parry in Sill. Journ. 1852: ovato-cylindricus, 
11-13 costatus ; aculeis radialibus sub-13 albidis, superioribus ceteris 
multo brevioribus, centralibus 4 longioribus angulatis rectis, 3 superi- 
oribus fulvis arrectis, inferiore longiore albido Sa seu deflexo ; 
floribus lateralibus ; seminibus tuberculato-scrobiculati 
Var. 8. cHRysocentrus, E. & B. in P.R.R.: seks radialibus 
12-14 albidis, centralibus 3 superioribus validis vitellinis erectis, infe- 
riore albo compresso deflexo. 
ar. y. vARIEGATUS, E. & B. |. c.: aculeis radialibus sub-13 albi- 
dis, centralibus 3 superioribus recurvatis divaricatis nigris corneo-vari- 
egatis, inferiore longiore albo decurvo. 
Lower Gila, Colorado, and westward to the California mountains : 
fl. June and July.— Stems 5-10 inches high; radial spines slender, 
3-6 lines, central ones 1-2 inches long. Fruit near the top of the 
plant. — Dr. Bigelow collected a little farther north, on Bill Williams’s 
Fork, the two forms which I have put under 8. and y.; though they 
differ from the species by having the fruit lower down on the plant ; 
‘the arrangement of the spines, however, is entirely identical. Var. B. 
has very stout central spines, 2-3 inches long, of a deep golden- 
yellow color, and the lower one shorter. In var. y. the central spines 
are only 1-2 inches long, much curved, and the upper ones white 
and black mottled. “ 
* * Coccinei; floribus diu noctuque apertis. 
16. ? C. conacantuus, E, & B. in P. R. R.: ovatus, subsimplex, 
7-costatus ; areolis remotis ; aculeis robustis angulatis seepe curvatis, 
radialibus 8 flavidis seepe basi obscuris, summo ceteris multo majore 
centralem multangulatum validum spe flexuosum subzquante. 
Near Zuni, in Western New Mexico, under cedars. — Radial spines 
8-15 lines long, upper one and central spine 14-24 inches long, 
remarkably stout, angular and channelled. —I have not seen the 
flower of this plant, but place it here from its resemblance to the next 
species ; on the other hand, it seems to be allied to C. Mojavensis. 
17. C. rricLocnipiatus, E. in Wisl. Rep.: : ovato-cylindricus, 6 —'7 
costatus, parce ramosus ; areolis remotis ; aculeis 3-6 robustis an- 
