CACTACE. 49 
more numerous, finer, and more crowded than in O. Engelmanni ; this arrangement of the 
bristles I find again only in 0O. ehlorotica, Eng. & Big., from the Western Colorado The 
spines resemble O. tortispina, Eng. & Big., the flower and fruit 0. Engelmanni, and the seed 
seems different from all these. Fruit 14-1} inch long, one inch in diameter; umbilicus 
? inch wide, shallow. Seeds 1.5-2.0 lines in diameter. 
O. ocorwentauis, E. & B. in P. R. R., found by Dr, Bigelow, ‘‘in immense patches, 40 miles 
east of Los Angeles,’’ California, was also observed by Mr. Schott in the high valleys of San 
Pascual and Santa Isabel, northeast of San Diego, ‘‘ covering extensive tracts of land.”’ It is 
probably a good species, and quite distinct from 0. Engelmanni ; young plants, raised from Dr. 
Bigelow’s seeds, do not show the peculiar capillary spines of that Species mentioned above. 
Another Opuntia grows on the hillsides and plains near San Diego, Parry, and on the sea 
beach there, Schott ; an erect plant, 4-6 feet high; spines 2-4, stout, compressed yellowish or 
brownish, also forming large thickets; joints 6-8 inches long and 4-6 inches wide; ovary 
subglobose, with 16-20 bristly pulvilli; 15-18 broadly obovate cuspidate sepals; about 8 (?) 
orbiculate petals ; 8-10 stigmata; a large yellowish or purple fruit, of pleasant taste, much 
relished by the inhabitants. Whether this is a form of 0. Engelmanni or O. Tuna, which, from 
having for a long while been cultivated about the settlements, may have become naturalized, I 
cannot at present determine. 
4. O. MACROCENTRA (sp. nov.): adscendens; articulis magnis suborbiculatis tenuibus seepe 
purpurascentibus; foliis gracilibus lineari-subulatis ; pulvillis subremotis orbiculato-ovatis setas 
graciles breves fulvas tomentum griseum vix superantes gerentibus plerisque inermibus, summis 
et marginalibus solum armatis ; aculeis 1-2 rarius pluribus prelongis rectis seu varie flexuosis 
fusco-atris sursum pallidoribus sepe annulato-notatis, superiore terete inferiore subbreviore 
compresso seu canaliculato ; flore flaro; ovario ovato ; pulvillis 20-25 villosis et fulvo-setosis 
Versus superiorem ovarii partem congestis ; sepalis tubi 13 lanceolatis seu interioribus obovatis 
acuminatis cuspidatisve ; petalis sub-8 obovatis obtusis mucronatis ; stigmatibus 8; seminibus 
majusculis late obtuseque undulato-marginatis. (Tab. LXXV, fig. 8.) 
Sandy ridges in the bottom of the Rio Grande near El Paso, also on the Limpia, Wright: fl. 
in May.—A remarkably striking plant 2-3 feet high—with large, almost rounded, thinly com- 
pressed, often purplish joints, and very long nearly black spines—of which it would be very 
desirable to obtain living plants, as none of those sent home by Mr. Wright have survived, 
Joints 5-8 inches long, 4-7 inches wide; leaves 24-3 lines long, remarkably slender ; pul- 
villi -1 inch apart ; lower ones smaller and closer together, unarmed ; spines on the upper 
ones 2-3 inches long, lower half almost black ; ovary 1} inch long, 8 lines in diameter ; flower 
3 inches in diameter when fully open.’ The seeds sent by Mr. Wright as belonging to this species 
are 2.0-2.2 lines in diameter, much twisted, their border undulating, very similar to seeds of some 
form of O. pheeacantha. From this species our plant seems to be distinguished by its larger, 
thinner, more orbicular joints, the closer and more woolly pulvilli, the slenderer leaves, and the 
small number of very long spines; the ovary also is more elongated, the sepals narrower, the 
flower larger. : 
5. O. pumacantua, E. in Pl. Fendl.: diffusa, adscendens ; articulis obovatis seu suborbicu- 
latis crassis glaucescentibus ; foliis e basi crassa subulatis; pulvillis subremotis orbiculato- 
ovatis setas graciles stramineas seu fuscatas tomento griseo plerumque longiores gerentibus 
: ; 1 ; i - . " asa . . 
