New Mevzico an 387 
sions in the rece , strata of fossiliferous lineata, 
filled with reme ns of erinoid % 
About thirty miles from Fors Se teri on a brane ie 
Wah-karussi, a bed of bituminous coal outcrops, whicl 
_ ed by the a al 
e F tha 
section. ‘Cacti and other spinose plants first made thelr appear- 
ance in 98° W., and near the same region the buffalo grass (Ses- 
leria? dactyloides, Nuit.) begins. 
Bent’s Fort is about 3958 feet above the sea, which gives for 
the Arkansas a fall of 7,4; feet per mile between this point and 
the meridian of 98° W., 2 distance of 311 miles. The river has 
sy flats of half to two miles in width ; but “beyond this the 
ground rises by gentle slopes into a wilderness of sand-hills on 
the soutie and into prairie on the north.” A conglomerate.of 
pebbles was observed along the river in this part, and higher up 
an argillaceous limestone containing ammonites, &c. “The soil 
of the plains is a granitic sand, intermixed with the exuviee of 
animals and vegetable matter, supporting a, scanty oe 
The eye wanders in vain over these immense wastes in seare 
trees. The principal growth is the buffalo grass, Cacti in am 
less variety, Yucca angustifolia (soap plant), etn capac brachy- 
loba, Schrankia uncinata, Cucurbita aurantia (prairie gourd), an 
very rarely that wonderful plant, the Ipomea lacie gi, called 
by the hunter, man-root, from the similarity of the root in size 
and shape to the bod of a man. It is esculent, and serves to 
sustain human life in some of the many vicissitudes of hunger 
and privation to which men who roam the prairies are subjected.” 
The only tree of any magnitude along the Arkansas, is the cot- 
tonwood (Populus canadensis). 
From Bent’s Fort south, they met with beds of limestone, 
sandstone, basalt and a porous volcanic rock. On the Moro, in 
latitude 35° 54’, “the plains were strewed with fragments of 
brick-dust colored lava and scoria, and the hills to the left were 
capped with white granular quartz.” 
On either side of the narrow valley of the Santa Fe—which 
varies from 1000 feet to a mileor two in width—* the country 
presents nothing but barren hills, utterly incapable, both from soil 
and climate, of producing sparring useful. The valley is en- 
tirely cultivated by irrigation.” “Five miles below the town, 
the stream disappears in ‘hea granitic sands” (p. 34). The height 
of Santa Fé above the sea, according to the barometric observa- 
tions taken, is 6846 feet; the neighboring peaks to the north are 
many thousand feet higher. The valley of the Del Norte to the 
south as far as Angosturas, was narrow with no interval for agri- 
culture. Below the last mentioned place, the = bpaee 3 ad 
a plain which is cultivated by irrigation. Farther so 
valley affords little land for cultivation, and the Gounlly oithne 
