200 
TRANS. OF THE ACAD. OF SCIENCE. 
ssepe globoso-obovatis vix tuberculatis ; areolis subapproxi- 
matis; foliis minutis'subulatis divaricatis; setis brevissimis, 
aculeis nullis seu parvulis seu rarius singulo longiore recto ro- : «j 
busto albido; fioribus sulphureis ; sepalis exterioribus trans- 
versis obcordatis cuspidatis; petalis 8 late obovatis emargi- 
natis; stigmatibus 8 brevibus erectis; bacca obovata areolis 
sub-25 stipata; seminibus irregulariter compressis anguste 
marginatis. 
In the Pass, west of Steptoe Yalley, in the Utah basin ; in 
flower and fruit at the end of July. Joints 2-3 inches longy 
and of nearly the same djameter; areolae 6-8 lines apart ; 
leaves smaller than in any other of our species, except 0 ba■* 
silaris , scarcely 1 line long; bristles few on young, none on 
old joints, about % L long; stouter spines, when present, i-1 
inch long. Flowers 3 inches in diameter, pale or sulphur- 
yellow ; fruit 1 inch long, half as thick, with a very deep um¬ 
bilicus and with a few bristles, or here and there a minute 
spine on the areblae^—in the specimens before me apparently 
fleshy, but perhaps dry at full maturity; seeds very irregular^ 
2 1. or in the longest diameter 2^ 1. wide. Loth to increase- ! 
the number of illy defined species, I provisionally attach this 
to the New Mexican O. sphoerocarpa , of which, however, 
leaves and flowers are as yet unknown, and the fruit is rather 
different. 
. 8. Opuntia hystericina, JEktg. Big., is evidently a west¬ 
ern representative, or may be a western form, of O . Missou - 
riensis. (See Bot,, Ives’ Exp., p. 14.) It was collected in ! 
the present Territory of Nevada, between Walker and Carson 
Rivers. Flowers 2^-3 inches wide, larger than in Dr. New¬ 
berry’s specimen ; stigmas 8-10, short, erect. 
9. Opuntia Missouriensis, JDeC., itself is not rare in the 
deserts between Salt Lake Yalley and Rush Yalley. Yar. 
ALBispiNA, approaching to var. trichophora, was found on 
Smith Creek, Lookout Mountains; flower 3-3i inches in di¬ 
ameter; ovary with 20 or 25 scarcely spiny areolae; 5 very 
short erect stigmas. 
10. Opuntia fragilis, Haw. Suppl.,p, <82 ; Cactus fragi- 
lis, Hutt.i gen. I, p. 296. Fort Kearney to the North Platte 
country, in flower in June and July. This, I believe, is the 
first time, since NuttalPs discovery in 1813, that the flowers 
of this species were collected. Travellers report the plant 
very common on the sterile prairies at the foot of the Rocky 
Mountains, but rarely found in flower, and still more rarely 
in fruit ; it seems to propagate principally by the extremely 
brittle joints, which even the wind is apt to break off and 
carry about. I have had for many years specimens in culti¬ 
vation, brought by Dr. Hayden, but have never been able to 
obtain flowers. Nuttall says the flowers are solitary and 
small; in the specimen before me.they are nearly 2 inches in 
