CACTACER. 47 
fine as an old man’s beard. The older joints become thick and of a solid ligneous substance ~ 
younger joints 43 inches long, 24 inches wide, or larger; pulvilli 4-5 lines apart; exterior 
spines 3—6 lines, interior ones 9-18 lines long. Fruit ovate, 10 lines long, 7 in diameter; very 
- slender and numerous spines, 3-6 lines long. Seeds, with those of O. hystricina, the largest 
known to us, 3} lines in diameter, sometimes larger; rim large, almost of the tickness of the 
seed itself. This is, perhaps, a distinct species, and must be further studied. 
14. O. spHaRocARPA, (sp. noy.): diffusa articulis orbiculatis transversisve tuberculatis; pul- 
villis confertis albo-tomentosis, setas stramineas breves gerentibus, plerisque inermibus, summis 
solum et marginalibus aculeos 1-2 reflexos s. patulos, adjectis subinde 1-3 brevioribus gerenti- 
bus; bacca globosa, umbilico minore plano, pulvillis sub-25 tomentosis setosis vix aculeolatis, 
seminibus mediis acute marginatis, (Plate XIII, figs. 6-7.) % >/%. 
On th@ eastern declivity of the Sandia mountains, near Albuquerque. Joints in the specimen 
before us 3 inches wide, less in length, strongly tuberculated ; pulvilli 4-5 lines apart; spines 
on the upper lateral pulvilli mostly single, deflexed, } inch long; on the middle or lower ones 
none; on the uppermost and marginal ones mostly 2, rarely 3 lines long, reddish brown, with g 
darker tip; 1-3 smaller additional spines, 2-4 lines long also reddish, Fruit perfectly globose, 
9 lines in diameter; umbilicus 5-6 lines wide; pulvilli bristly, but only the upper ones with 
one or a few small spines. Seeds 2} lines in diameter, very irregular, with a rather narrow, 
but sharp rim. 
The arrangement of the spines is so different from any form of 0. Missouriensis, which always 
shows the numerous slender radiating spines, and always has spiney fruits, that we feel obliged 
to separate this plant as a distinct species. The seeds brought home by the expedition have 
germinated, and are growing vigorously. 
15. O. ERINAcEA, (sp. nov.): diffusa adscendens; articulis tumidis ovatis s, teretiusculis, 
pulvillis confertissimis ovato-orbiculatis albo-tomentosis demum stramineo-setosis omnibus arm- 
atis ; aculeis 3-5 gracilibus elongatis e cinereo-rubellis 1-3 superioribus brevioribus sursum 
porrectis, centrali longior patulo vel declinato, ceteris deflexis, additis 2-4 minoribus inferiori- 
bus ; bacca ovata umbilico infundibuliformi pulvillis 30-40 setad stramineas et aculeolos 12-20 
gerentibu: ; seminibus magnis subregularibus late acuteque marginatis. (Plate XIII, fig. 8-11.) 2XKIK 4 | 
West of the great Colorado near the Mojave creek; joints 2-24 inches long, 1-14 inches wide, 
and about 3-} inch thick, sometimes elongated, almost cylindric, densely covered with the large 
white pulvilli, which are only 2-3 lines apart, and numerous reddish-gray spines with red 
points bristling hedgehog-like (whence the specific name) in every direction. Spines 6-14 or 
in old joints even 20 lines long, with smaller ones.very slender, flexible, but stiff. Young 
plants cylindric, covered with bunches of 15 or 20, or more, white hair-like spines. Bristles 
dirty-yellow even in young joints present, in old ones densely crowded, and 2-3 lines long; in 
a dead flower a 6-parted stigma was noticed. Fruit 1-1} inches long, about } an inch in 
diameter, with a deep funnel-shaped umbilicus ; pulvilli crowded, prominent, white-tomentose 
with yellowish bristles and numerous, mostly deflexed, spines, 3-6 lines long. Seed nearly 3 
lines in diameter, much compressed, more regular than in the three foregoing species. 
15. O. BRACHYARTHRA, (sp. nov.): prostrata s. adscendens, articulis ovatis s. orbiculatis tumi- 
dis saepe subglobosis, tuberculatis ; pulvillis confertis magnis albo-tomentosis parce setulosis 
plerisque armatis ; aculeis 3-5 albidis s. fuscatis patulis; 1-2 validioribus sursum versis, caeteris 
minoribus minimisge subdeflexis; floris parvig ovario subgloboso, pulvillos 12-15 tomentosog 
setosos superiores aculeolatos gerante, sepalis tubi exterioribus obovatis cuspidatis stigmatibus 
5. (Plate XII, fig. 9.) 
At the foot of the inscription rock near Zuiii under pine trees, only seen in that single 
locality. A singular looking plant with short tumid joints (10-15 lines long, 10-12 wide and 
