222 The Mesozoic Series of New Mexico. — Marcou. 
the fine-grained sandstones that cap them, and the second 
series, Triassic ; and that the remaining sedimentar}^ beds are 
composed of Carboniferous, and possibly some Permian exists 
in that region." Exactly what any geologist passing over that 
road, with my geological map of New Mexico of 1853 in hand, 
would have said. No fossils quoted, no geological map, no 
detailed section; so Dr. Hayden's reconnoissance of 1869, 
from Pecos to Santa Fe, was simply a summary repetition of 
my observations. 
1879. Stevenson. Now we come to the survey executed 
"somewhat closely, from Las Vegas to Galisteo creek in 1879," 
by professor J. J. Stevenson. It is published in a 4to volume, 
called vol. iii, Supplemetit, Geology; Wheeler's TJ. S. Oeogr. 
surveys west of the 100th meridian, Washington, 1881. 
The volume contains fossils, sections and a geological map 
of a "Part of north central New Mexico," touching and em- 
bracing in its limit some part of my geological map of New 
Mexico of 1853, so that comparison may be made. Scale of 
the map 1 : 253, 440. We must say at first that no Mesozoic 
fossils are figured or described , and that no list of species is 
to be found in any part of the volume, which relate to the 
Mesozoic rocks. "The title used by professor Stevenson in 
his paper in The American Geologist, vol. iii. p. 391 : "The 
Mesozoic rocks, etc.," seems to imply that his classification 
and description are entirely based on paleontology; but on 
the contrary, all his remarks, descriptions and classifications, 
as well in his paper as in his large 4to volume, are purely 
lithologic ; the palaeontology is never mentioned anywhere, 
and even the stratigraphy is seldom referred to, more espec- 
ially the discordance of the strata, which is passed entirely 
unnoticed. 
The classification on the map is : 
( Laramie. 
Cretaceous. \ Colorado. 
( Dakota. 
Linear outcrop of Jura-Trias. 
Carboniferous. 
Besides these are special divisions for the Tertiary, Quater- 
nary, Igneous and Crystalline rocks. 
Let us compare the only two geological maps of central 
New Mexico, of a tolerably large scale, in existence until 
