58 The American Geologist. .F;m. isoi 
ellipsoid anticlinals of very steep dips and faults, respectively about 
twelve and seven miles long, situated east of the I'iuta mountains, on 
the low. inceptive portion of their broad fold. 
The geologic formations exposed in the I'iuta anticlinal, as madi 
known by Powell, King. Hayne. Emmons, and White, are the Uinta 
sandstone. 12,000 to 14,000 feet thick: Carboniferous limestones and 
sandstones, 3.000 to 4,000 feet: Jura-Trias strata, mostly sandstones. 
3,500 to :,,000 feet; and the Dakota. Colorado, Montana and Laramie 
series of the Cretaceous system, aggregating 0.000 or 7.000 feet. Over- 
lying the edges of this mountain mass, and included with its uplift in 
successively diminishing amount of tilting, are the Wahsatch, Green 
River, Bridger. and Brown's Park fresh-water Tertiary formations, with 
aggregate maximum thickness of 7,700 feet. 
Elevation of the great Uinta fold began, according to Dr. White, at 
the close of the Laramie period, when epirogenic movements finally cut 
off the brackish Laramie sea from all connection with the ocean. The 
folding and uplifting were in progress during the Eocene epochs of the 
Wahsatch, Green River, and Bridget- lakes: and were nearly completed 
before the deposition of the Brown's Park beds, which rest unconform- 
able upon all the other formations and are probably of Pliocene age. 
The vertical extent of the Uinta uplift, occurring thus during the Ter- 
tiary era, is shown to have been about :.'8,800 feet, or five and a half 
miles; but, owing to erosion, the range has probably inner greatly ex- 
ceeded its present hight of 10,000 to 13,000 feet. 
In the small Junction mountain and Yam pa mountain upthrusts, 
the vertical displacement of each has been nearly 12,000 feet, and this 
has taken place contemporaneously with the Uinta uplift. Indeed. Dr. 
White finds, by the extension of his observations and study eastward 
from the Uintas to the Park range of the Rocky mountains, that both 
these prominent ranges, their subordinate folds and spurs, and the two 
upthrust mountains, are all '-results of one great system of orogenic 
movements.'* So slow has been the elevation, however, not only of the 
Uinta range, but also of the isolated Junction and Yampa mountains, 
that rivers which traversed their areas when the uplifting began, nave 
not been turned out of their courses, being able to erode and deepen 
their canons through these mountains as fast as their rise, to total 
hights of two to five miles, progressed. 
Nicholson & LydeKker'8 Palaeontology: — The second volume of this 
great work comes from the pen of the latter of the two authors who are 
associated on the title page. Mr. Lydekkcr's name lias been familiar 
to the student of vertebrate palaeontology for many years past, and no 
one will dispute, his competence for the task. His introductory chap- 
ter on the comparative anatomy of the various classes of the sub-king- 
dom Vertebrata, forms an excellent summary of our present views regard- 
ing the relationship of their organs in the light of Evolution. 
Passing over as an unsolved problem the origin of the Vertebrata from 
the invertebrate sub-kingdom the author selects from the totality of the 
