Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean: Vol. 4, Pt. 3

'ACTAOEs.5
parce tomentomis vix setosis; aculeis brevibu's cinereo'. stramin'eo vaginatis, 1-4 majoribus
divaricatis, inferiore longoiore deflexo, minoribus 2-8 solum ad infriorea puivilli marginem
deflexis s. undique radiantibus; flore tubro, ovario ovato tuberculato pulvillis 20-30 tomentosis
Setas stramineas et aculeolos paucos mox deciduous gerentibus stipato sepalis tubi sub-8 orbiculatis cuspidatis, petalis 8-10 spathulatis cuspidatis; bacca subglobosa leviter tuberculata subcarnosa flava inermi; umbilico infundibuliformi seminum subregularium commissura lineari.
a. LtEVIOR humilior, aculeis brevioribus paucioribus seminibus minoribus.
. SPINO0SIOR elatior aculeis plurimis longioribus seminiibus majoribus. (Plate XVII, fig. 1-4.)
From the elevated country about Zuni to the head of Williams's river, at first seen only 8-15
inches high, subprostrate, afterwards 20-30 inches, and seometimes even 5-6 feet high. Var. p.
was found by Mr. A. Schott south of the Gila river, and he also discovered the flower of this
plant, which, like the flowers of all the other new species, remained unknown to us, unless
winter remains were picked up here and there. Ligneous skeleton tubular, with small meshes,
dense at base of stem; joints elongated, 2-4 inches to a foot long,. j or ~ of an inch in diameter;
tubercles ovate or sometimes almost rhombic, about 5 lines long; spines very variable in number,
sometimes only with 1 larger and 2 or 3 smaller ones; in other instances, especially in Var. p.,
with 12 or 14; spines 3-9 lines lohg, bristles few, generally only on older joints; flowers 1~-1
inches in diameter; ovary 6-9 lines long with 20 or 25 pulvilli; fruit about I inch long, a little
less in diameter, somewhat fleshy and sweet, with 25-35 not very prominent tubercles; seeds
with linear or almost linear commissure, 1~-1- lines in diameter; cotyledons regularly incumbent or sometimes oblique. The seeds of r. are 2 lines in diameter.
This is easily distinguished from all the allied species of the slender elongated branches, the
short, crowded tubercles, and the short spines. We have dedicated this Opuntia, characteristic
of the desert mountains under the 35th degree, between the Rio Grande and the Colorado, to
Captain A. W. Whipple, the commander of the expedition who, by his zealous and liberal cooperation, afforded every facility in his power in the various collections of natural history(Plate XVII, fig. 5-6, and Plate XVIII, fig. 4.)
23. 0. ARBO:RESCENS, EnglM.: found first 200 miles east of the Pecos, and from there abundantly as far west as Zuni, where other cylindric Opuntic take its place. In this region it does
not grow higher than 5-8 feet, and can scarcely be called arborescent; it is always well characterized by the verticillate often somewhat pendulous branches, the cristate-tuberculate spineless
fruit, and the smooth seeds with a distinct and broadly linear commissure, Seeds of specimens
collected at Zuni smaller than others, ouly 11 line in diameter.
24. O. ACANTIHOCARPA, (sp. nov.): caule arborescente erecto reticulato-lignoso, ramis adscendentibus divaricatis articulis cylindricis tuberculatis pallide virescentibus, tuberculis oblongolinearibus pulvillis ovato-orbiculatis breviter tomentosis vix setosis, aculeis numerosis s. plurimis
(8-25) stramineo-vaginatis undique porrectis, stellatis; bacca subglobosa late umbilicata
tuberculata; pulvillis 12-15 tomentosis parce setosis aculeolis validis 8-10 munitis; seminibus
magnis muetangulis late commissuratis. (Plate XVIII, fig. 1-3.)
On the mountains of Cactus Pass, about 500 miles west of Santa Fe. Stout, stem 5-6 feet
high, wood forming a hollow reticulated tube, solid at base; branches few, never verticillate
separating at acute angles; joints 4-6 inches long, 1 inch in diameter, tubercles 9-10 lines long;
pulvilli in some with one central and 6 or 8 exterior spines, in others with 3-7 interior and
10-20 exterior stellately radiating spines. Central spines 1-1+ inch, exterior 4-10 lines long,
with a yellowish or brownish sheath. Fruit 1 inch long with a large but not deep umbilicus,
and 12-15 rather shallow tubercles; spines of fruit stout, 3-6 lines long, stouter and more
crowded toward the top of the fruit. Seeds unlike any other of our Opunti,e 21-3 lines in
diameter, with rather broad commissure, often spongy on the margin, and on the sides with
many even or concave faces separated by sharp ridges.
5.1