162 CACTACEA OF WHIPPLE’S EXPEDITION. 
2. O. ENGELMANNI, B.? cychopEs: erecta, articulis orbiculatis, pulvillis remotis tomento griseo setisque 
stramineis rigidis ineequalibus instructis ; aculeis subsingulis rectis validis compressis stramineis basi fuscis deflexis, 
adjectis sepe 1-2 none brevioribus pallidioribus ; bacca globosa late umbilicata, seminibus late undulato- 
inarginatis. (Plate VIII. 
ut the mouth of te Gattiads, into the Pecos, near Anton Chico, New Mexico ; collected in fruit in [38] 
September. Plant 4 feet high ; joints orbicular, or even transversely oval, about 7 inches in diameter ; pulvilli 
1 inch apart, large, with a semicircle of large, coarse bristles, 3-4 lines long at the upper edge, wan a single stout 
spine, 1}-12 inch long, on the upper pulvilli, often with 1 or 2 additional ones, 4-9 lines in length. Flower not seen. 
Fruit globose, 1-1} inhi in diameter, of a purple color. Seed 2.0-2.3 lines in diameter, with a broad and thick acutish 
undulate rim, The circular joints with fewer spines, and the small aie fruit with large seeds, distinguish this 
form from 0. Engelmanni, as it a appears farther south, 
O. IDENTALIS, sp. nov.: erecta patulo-ramosissima, caule demum lignoso tereti corticato, articulis 
grandibus obovatis shombbiddeves ulvillis remotis griseo-tomentosis, setis flavis s. flavo-fuscis gracilibus confertis, 
aculeis 3 validis compressis angulatis rectis deflexis divergentibusve, uno alterove ad articuli marginem aOp rere 
Ibidis corneisve subannulatis basi flavo-fuscis cum adventitiis 1-2 gracilioribus pallidioribus deflexis ; flore 
flavo intus aurantiaco, ovario obovato pulvillis fusco-villosis vix fulvo-setosis sub-25 notato subinde parce scalen: 
lato, sepalis (extus rubellis) 10-12 dilatato-obovatis cuspidatis, petalis (8?) obovatis obtusis subintegris; bacca 
tg umbilicata succosa, seminibus majoribus irregularibus undulato-marginatis, crenulatis. (Plate VII. 
figs. 1 
oe the western slope of the California mountains, from Quiqual Gungo, east of Los Angeles, to San Pasquale 
and San Isabel, northeast of San Diego (A. Schott), at an elevation of 1,000 to 2,000 feet, in immense patches often as 
large as half an acre. Flowers in June. Stout ligneous stems, with innumerable branches, sometimes over 100 joints, 
spreading far, and then often bent to the ground ; joints 9-12 inches long, 6-8 inches wide; pulvilli 1}-2 inches 
distant, with slender and closely set (much more so than in O. Engelmanni) bristles, only 2-3 lines long on the upper 
part of the pulvillis ; spines 1-1}, smaller ones }-? inch long. Flower yellowish and orange, deeper colored inside at 
the base, 3-3} inches in diameter ; ovary 1} inch long, not 1 inch in diameter, pulvilli pretty equally distributed over 
it (not as much congregated toward the top as in 0. Engelmanni) ; sepals short and unusually broad ; = only 
9 or 10 lines wide by 15 lines in length, rounded, and not emarginate in my specimen, nor mucronate. Fruit 2 inches 
long, 14-14 inches in diameter, “ very juicy, but of a sour and disagreeable taste.” Seeds 2}—2? lines in fares 
The young plants, raised from the seeds which we brought home, fail to exhibit the very hairy pulvilli which all the 
young of 0. Engelmanni show; they bear only the numerous belatly spines seen in most young Opuntia, at least of 
this section. 
To Mr. A. Schott, who has considerably enriched our knowledge of the vegetation of the countries along the 
boundary line and in the Gadsden purchase, is due the credit of having discovered the flower of this plant, heretofore 
unknown, and of many valuable notes about its general habits. 
The plant mentioned in Silliman’s Journal, November, 1852 (Dr. Parry’s collections), as being common 
“on the hill-sides and plains near San Diego,” and which Mr. Schott seems to have also found “on the sea-beach near 
San Diego,” may be a form of O. Engelmanni, as suggested in in the above publication ; or it may be a naturalized wild 
state of O. Tuni, which is aaa about the missions there. Enough material has not been obtained to decide 
about it. At all events, it seems to be distinct from the plant of the western mountain slopes. 
4, O. CHLOROTICA, sp. nov.: erecta, grandis, caule demum-lignoso terete, cortice cinereo-fulvo aculeis flavis 
numerosissimis fasciculatis armato 3 ; articulis orbiculato-obovatis magnis pallide flavo-virescentibus s. subglaucis ; 
pulvillis subremotis griseo-tomentosis, setis stramineis difformibus exterioribus brevioribus tenuioribus subsequalibus 
ib 
epee: interioribus, uniseriatis robustioribus longioribus ; aculeis in pulvillis inferior! us 1-3, in jee aon 
us stramineis plus minus compressis (nec acute angulatis) ple in ue deflexis, interiore lore 
wiabine erecto ; 5 tote flavo, ovario tubercula pulvilli-gera conferta sub-50 gerente; sepalis tubi sub-20 Seas [39] 
bovata 
latis cuspidatis, petalis sub-10 obovato spathulatis, obtusis mucronatis, stigmatibus 8 patulis ; bacca obova 
tuberculosa profunde umbilicata. (Plate VI. figs. 1-3.) 
th sides of the Colorado, from the San Francisco mountains to the headwaters Williams's River — eome- 
times called “ Bill Williams’s Fork” —and to the Mojave Creek. The only erect, flat-jointed Opuntia in this section 
of country, 4-5 and sometimes even 7 feet high, forming large bushes, on one of which upwards of 100 joints were 
counted. The large trunks have a scaly, grayish, or light-red brown bark ; the pulvilli are not obliterated on it, as- 
they are on O. Engelmanni, but are largely developed, 4-6 lines in diameter, pulvinate, om covered with a thick 
brown tomentum, surrounded by numberless straw-colored bristles, 4 lines in length, and bearing 20-30 or more 
yellow compressed spines, often 1-2 inches in length, stellately radiating in every direction, ane covering and shielding 
the whole surface of the stem. The only Opuntia which I find described as having a similarly armed stem 1s 
O. Karwinskiana, Salm, which is said to have 18-20 gray spines on the oldest pulvilli. 
