46 CACTACEA. 
5-10, inferioribus albidis, superioribus robustioribus rufescentibus centrali subsingulo robusto 
fusco patulo s. deflexo ; bacca depresso-globosa, umbilico lato plano, pulvillis sub-25 aculeolos 
5-10 breves gerentibus.—(Plate XIV, fig. 4.) 
Sent from the Yellowstone by Dr. Hayden. A stout form ; joints 3 inches long, 23-28 wide; 
pulvilli 4-6 lines apart, the dirty yellowish bristles visible only on the older joints. Central 
spine single, or only on vigorous specimems on the upper pulvilli 2, mostly brownish, deeper 
colored on the margin. Fruit 8-9 lines long, umbilicus, of the same diameter, spines only 1-3 
lines long, deflexed, Seed 3 lines in diameter, rim rather narrower than in the first-mentioned 
form. 
y MICROSPERMA ` articulis ut in precedente; stigmatibus 5; bacca ovata, umbilico parum de- 
presso, pulvillis, 20-30 setosis et breviter aouleolatis, seminibus anguste acuteque marginatis. 
(Plate XIV, figs. 5-7.) 
On the Missouri, about Fort Pierre; brought down 10 years ago by the fur traders. Very 
similar to tI e last form in the general appearance; also with only 1, or at most 2, central dark 
spines; flowers only with 5 stigmata, otherwise same as the one described above; fruit short, 
oval, with 10-20 very short spines on the numerous pulvilli ; seed only 2 lines in diameter, more 
regular, thicker in proportion, with a narrow and acute rim. It might be supposed that these 
characters were important and constant enough for a specific difference, if we did not know the 
great variability in this genus, and if we did not find among uf Hayden's plants seeds of 
intermediate shape and size. 
d SUBINERMIS: articulis elongato-obovatis, pulvillis subremotis, inferioribus, inermibus, supe- 
rioribus aculeos paucos breves gerentibus. 
Brought from the Upper Missouri by Dr. Hayden; remains constant in three years cultivation. 
Joints 34-5 inches long, half as wide, gradually narrowed down at base; leaves entirely similar 
to those of the common form; pulvilli 6-9 lines apart; spines entirely wanting, or on the upper 
pulvilli 2 or 3 short and slender ones, rarely one or the others more robust, 44 inch long; 
flowers not seen. 
€ ALBISPINA ` articulis late obovatis, setis stramineis, aculeis omnibus albis gracilioribus, exte- 
rioribus 6-10 setaceis, interioribus in pulvillis superioribus 1-3 robustioribus elongatis deflexis 
8. patulis; bacca ovata, seminibus magnis. (Plate XIV, figs. 8-10.) 
Sandy bottoms and ës beds of streamlets on the Upper Canadian, 250 miles east of the Pecos; 
on the Sandia mountains, near Alhuquerque; also, on the Upper Missouri. This was the first 
form of this species met with in travelling up the Canadian; the stouter and more compact 
forms were found further west, in higher elevations. Joints 3-4 inches long, 24-3 wide; pul- 
villi 4-6 lines apart; spines all ivory white, rarely with a yellowish tinge, larger ones 1—4 inch 
long; fruit with very shallow umbilicus, and very slender and short spines; seed 3-33 lines in 
diameter, irregular, rim broad acutish. A form from the Sandia mountains with pulvilli more 
remote; spines longer, more slender, some of them flexuous; seems to unite this with the next 
variety. 
Č TRICHOPHORA: articulis — pulvillis confertis parce albo-tomentosis setas stramineis 
demun albidas breves gerentibus, omnibus armatis; aculeis 10—18 setiformibus albis, exte- 
rioribus 8-12 brevioribus radiantibus, interioribus longioribus deflexis, rarius singulo suberecto ; 
pulvillis in articulis vetustioribus lignosis confertissimis setas numerosas aculeosque 15-25 
capillaceos elongatos flexuosos gerentibus; bacca ovata, umbilico parum immerso pulvillis 35-40 
albo-tomentosis stramineo-setosis fasciculum aculeolorum 12-18 plerumque deflexorum gerenti- 
bus; seminibus maximis valde compressis irregularibus latissime acuteque marginatis. (Plate 
XV, figs. 1-4.) 
Only on the volcanic rocks about Santa Fé, and on the Sandia mountains. The hoary appear- 
ance of the older joints is very characteristic, and reminds one strongly of Pilocereus senilis. 
These hairs are from a few lines to 2 or 21 inches in length, and of the appearance and about as 
