164 CACTACEZ OF WHIPPLE’S EXPEDITION. 
gerentibus plerisque armatis; aculeis 1-3 s, ad marginem pluribus compressis fuscis s. atro-fuscis versus apicem 
pallidioribus superioribus elongatis suberectis ceteris ddeflexis gracilioribus flore? Bacca ovata late umbilicata atro- 
rubente succosa pulvillis remotis obsoletis seminibus majusculis irregularibus angulatis late marginatis. (Plate IX. 
figs. 1-5. 
On the Llaiio Estacado, at the base of the hills, in rather fertile soil, from the eastern slope of that elevated 
plain to the Tucumcari hills, near the upper course of the Canadian River. A large plant, spreading extensively, with 
large rounded joints 6-7 inches long by 53-7 wide ; pulvilli about 1} inch remote ; bristles dirty yellowish, greenish, 
or brown, inconspicuous except at the upper edge, where they often become elongated and stouter. Only the lowest 
pulvilli are spineless ; the others bear 2-3 and the marginal ones 3-6 spines ; larger ones 1}-2 and in some specimens 
almost 3 inches long. Flower unknown. Fruit very ee distinguishing this species from the nearly allied 
O. pheacantha ; it is oval, not narrowed or constricted at base, 14-2 inches long, 1-1} inch in diameter, with a large 
flat umbilicus #+1 inch in diameter, considerably resembling the fruit of O. Engelmanni, of a deep red color, and a 
very sweet juicy pulp. Seeds 2}-3 lines in diameter, very cenepilicx angular and often twisted, with sides impressed, 
mostly with a broad and thick acute or obtuse rim deeply notched at the hilum. 
O. TORTISPINA, sp. nov.: prostrata, articulis majusculis adscendentibus obovato-orbiculatis, pulvillis [41] 
subremotis stramineo s. fulvo-setosis ; aculeis 3-5 majoribus compressis angulatis subinde canaliculatis sepe 
spiraliter tortis, albis hs apiceque we corneis, adjectis infra aculeolis 2-3 gracilibus albis ; flore ; bacca ovata 
areolis sub-20 parvulis notata, late umbilicata, seminibus majusculis regularibus crassis. (Plate V. : 5 
On the Gatapuasti Sass near the Canadian River, east of the plateau of the Llaiio Estacado. Pode in growth 
to the more Western O. Camanchica. Joints rounded, 6-8 inches long; pulvilli 1-1} inches apart ; bristles short, 
except on the edges, where they are 2-3 lines long, but rather slender ; spines more numerous than in any other of our 
species, with juicy fruit, often 6-8, lower smaller ones 4-1 inch, arger ones 13-23 inches long, entirely white or 
yellowish horn-colored at base and tip ; on the upper areole 1 erect spine, the others spreading in different directions, 
lower ones deflexed. Fruit similar to that of last species, large, oval, not contracted at base, perhaps less juicy and 
with a somewhat smaller and deeper umbilicus, 17-2 ay long, 1-1} in diameter. Seeds 2-3 lines across, thick and 
quite regular, with a very slight indentation at the hilur 
I had observed that sometimes two plants are paitien from the same seed. This I found to be the case 
occasionally with Opuntia occidentalis, Engelmanni, and dulcis, one of the young plants always much larger and more 
vigorous than the other. In examining different seeds of this species, I succeeded in finding one with two embryos, 
(see figure), one spirally coiled around the other, both together appearing like one large one. 
10. O. Rarivesqui, Engelm.: diffusa radice fibrosa, articulis . s. majusculis obovatis s. suborbiculatis 
per-viridibus ; foliis subulatis elongatis patulis pulvillis subremotis albido-s. griseo-villosis setas graciles rufas’ un 
elongatas gerentibus plerisque inermibus ; aculeis paucis plerumque ln pacaie validis teretibus rectis albidis 
seepe basi apiceque rufescentibus erectis s. patulis, singulis s. uno alterove graciliore deflexo adjecto ; floris alabastro 
conico acuto, ovario clavato pulvillis 20-25 griseo-villosis doepor along ; sepalis tubi sub-13 oblanceolatis 
acuminatis, interioribus late petaloideo-marginatis ne ose petalis 10-13 late obovatis eroso-denticulatis su 
inatis sulphureis basi intus miniatis, stigmatibus 7-8 erectis adpressis fluvo-albidis ; bacca ovata basi angustata 
clavata subnuda pulposa purpurascente, at sauce ‘lor immerso; seminibus subregularibus compressis, 
margine plerumque lato compresso sub-acuto. Var. crosperma wibicwbass seminibus minoribus regularibus 
angustius marginatis., (Plate XI. figs. 1-3.) 
In sterile, sandy, or rocky (consisting as well of sandstone as of limestone) localities in the Mississippi valley, Ili- 
nois, Missouri, Arkansas, and north to Wisconsin, east to Kentucky, and south probably to Louisiana and Texas ; west- 
ward it has not been found west of the western boundary of Missouri and Arkansas. Flowers in May and June; fruit 
ripens in the same season, but remains on the plant till the following spring. Joints rather large, orbicular 3-4 inches 
in diameter, or obovate 4-5 inches long by 3 in width ; a small variety with orbicular joints only 2 inches in diameter 
occurs on sandstone rock in southern Missouri. The color of the plant is dark or fresh green. Leaves 23-4 lines long, 
diameter about one-fourth of the length ; pulvilli 9-12 lines apart, with short whitish or grayish wool, and bright red- 
brown bristles conspicuous even in the youngest joints. Spines rarely none, generally few in var. microsperma, some- 
disa) 
single or rarely 2-3, 9-12 lines long, rather stout, white with a darker tip, and sometimes also darker base. 
23-3} inches in diameter, qulgliue-yeliow, mostly with a red centre. Fruit 13-2 inches long, less than half that in 
diameter, narrowed at base, the seminiferous cavity not extending to the base ; umbilicus funnel-shaped, but with 
shallow bottom, much wrinkled and scarred ; naked by the disappearance of the bristles of the pulvilli ; an 
edible, somewhat acid or sweetish. Seeds 23 lines in diameter, hardly more than 1 line in thickness ; rim [42] 
rather narrow, thick, but acutish. Var. microsperma has seeds only 0.8 or 0.9 line in diameter, more compressed, 
with quite a narrow rim 
