CACTACEA OF SIMPSON’S EXPEDITION. 231 
he species was bran! discovered on the Little Colorado by Dr. Bigelow, and was found afterward on the 
same stream by Dr. Newberry. The variety here described was met with more than five degrees farther north, in 
Desert Valley, west of Camp Floyd ; remains of fruit, with the withered flowers attached, and some seeds, were found 
concealed between the spines, from wrhtich the description has been drawn.* Globose heads 3 inches in diameter; radial 
spines 3-1} inch long, central ones 1}-2 inches in length. Flowers, if I may judge from the withered remains, about 
1 inch long; ovary small, bearing about 5 membranaceous scales, the lower triangular, the upper oblong-linear, almost 
entire, and never cordate or auriculate at base, as they appear in most of the allied species ; pee of tube also narrow, 
linear, or ee 2-5 or 6 lines long, 3-1 line wide; stigmas about } line long. Fruit apparently an oval 
berry, $ inch long. Seed just as it is described and figured in Whipple’s Cactacewx ; the rel on the seed- 
coat are extremely minute and distant from one another, each forming a central protuberance on the otherwise flat 
surface of an angular cell of two or three times the diameter of the tubercle itself; embryo curved about ? around a 
rather copious albumen. 
CEREUS VIRIDIFLORUS, Engelm. in Wisliz. Mem., note 8, sub Echinocereo; Cact. Mex. Bound., tab. 36; 4 
Cact., p. 22. This is evidently the northernmost Cereus, extending to the upper Platte ; it is sbandiened in Colorado. 
These northern specimens are 1-3 inches high, 13-ribbed, and show the greatest vatiobility 4 in the color of the radial 
spines ; in some bunches they are all red, in others white. In others again the colors are distributed without much 
regularity ; sometimes the upper and lower spines are white and the lateral ones red, or a few or even a single one 
above and below are red and all the rest white, or the lower ones are red and the upper ones white, and all these 
variations sometimes occur on the same specimen. I mention this to show how little reliance can be placed on the 
colors or the distribution of the colors of the spines. Central spines wanting, or one or two projecting horizontally, 
straight or curved upward, white or tipped with purple or all purple, 6-9 lines in length. 
C. EncGEeLMAnnI, Parry in Sillim. Journ., n. ser. 14, p. 338; Engelm. Cact. Bound., p. 36, tab. 57; Synops. 
Cact., p. 27. Deserts west of the Salt Lake, without flower or fruit. Specimen entirely wiuilar to the one figured in 
the Cactisee of the Boundary. The species seems to extend from the Salt Lake region southwestwardly to Arizona 
and the Mohave country. 
OPUNTIA SPHZROCARPA, Engelm. & Bigelow, Pacif. Rail. Rep. IV. Cact., p. 47, tab. 13, fig. ee [441] 
Synops. Cact., p. r.? Uranensis: diffusa, lete-virens, articulis orbiculato- shovutls crassis, junio 
seepe glibodo-cbewsding mes subapproximatis ; foliis minutis subulatis divaricatis; setis brevissimis paar strami- 
neis; aculeis nullis seu parvulis nunc singulo longiore recto robusto albido; floribus sed petit: ovario obovato areolis 
fasco-tomontadin sub-25 instructo, sepalis exterioribus transversis obcondatis cuspidatis ; petalis 8 late-obovatis emargi- 
natis ; stylo vix supra stamina exserto; stigmatibus 8 brevibus os ; bacea obovata areolis plurimis tomentosis 
iioata seminibus numerosis irvegulasitor compressis anguste margina’ 
ass west of Steptoe Valley, in the western mountains of the stig found July 19 in flower and fruit. Joints 
2-3 inches ne and of almost the same diameter, often over } inch in nie weer sometimes almost terete, or rather 
egg-shaped ; areole 6 or 8 lines apart ; leaves very slender and acute, scarcely 1 line long, smaller than in any other 
of our aun except 0. basilaris, also a western form from the lower Colorado ; bristles few, and even in old joints 
scarcely more than $ line long ; apes none, or on the upper areole a few short ones, with here and there a stouter 
one 3-1 inch in length. Flow early 3 inches in diameter, pale or sulphur-yellow; when fading, reddish. Fruit 
about 1 inch long and half as ek, with a deep umbilicus, and with 20-25 areolee, which sometimes show a few 
ristles or a minute spine. Seeds very irregular, 2, or, in the largest diameter, sometim: 
es 2 
Unwilling to increase the number - ill-defined species in this most difficult genus, I ing ‘this plant to the 
only species known to me to which it possibly can be compared, — O. spherocarpa, from New Mexico, —though its 
fruit is not spherical, has not a shallow umbilicus, and is, at least in the specimen before me, not dry. The latter 
would be an ee distinction, if we might not suspect, what in fact is often the case, that the fruit later in the 
season would become dry and brittle. The leaves — which heretofore have been entirely too much neglected as a 
diagnostic character in this genus — and the flowers of the original O. sphewrocarpa are unknown thus far. 
O. tortisprna, Engelm. & Bigelow, 1. c., p. 41, tab. 8, fig. 2-3 ; Synops. Cact., p. 37. Forks of the Platte ; 
flower in July. The specimens being very incomplete, I am not quite sure that this is the same species as that of 
Captain Whipple’s Expedition ; the joints appear to be — smaller, the areole closer together, and the spines 
shorter (1-1} inch) and rather weaker. Tt may possibly prove to be an extreme form of 0. Rafinesquii, the area of 
which extends to the Rocky Mountains. Leaves subulate, : lines long ; flowers 24-3 inches in diameter, sulphur- 
yellow ; ovary long (1-13 inch), with 20-30 areole, with light brown wool and short bright brown bristles ; exterior 
sepals obovate, lance-cuspidate ; petals 6-8, broadly obovate, obtuse, crenulate ; stigmas 6-8, short, erect, as long as 
the stamens. 
8 The botanist of Dr, Hayden’s Expedition of 1875, Mr. Brandegee, found it abundantly in southwestern Colorado. 
