1885.] Recent Literature. 153 
Nearly all the valleys which combine to form the basin of Lake 
Lahontan are due to profound fractures, the displacements in 
‘numerous instances extending 4000 or 5000 feet. These move- 
ments are thought to be still in progress, the mountains through- 
out the Great basin either slowly rising or sinking. ‘ As a mat- 
ter of observation we find the evidence of recent faulting best 
defined along the bases of the highest of the ranges, indicating 
that these owe their distinction to the fact that they are still 
growing.” , 
An important contribution to glacial geology is Thos. C. 
Chamberlin’s preliminary account of the terminal moraine of the 
second geological epoch, illustrated by excellent maps and views. 
This second great terminal moraine marks a general advance of 
the great ice-sheet at a date considerably later than the stage of 
greatest glaciation. The great terminal moraines of the first 
glacial epoch have been traced from Cape Cod to Ohio and Ilin- 
ois, but in the interior of the continent this “supposed extreme 
outer moraine has not been traced out.” The author believes 
that the western portion of what was supposed to be the great 
terminal moraine of the first epoch is, in Michigan, Wisconsin, 
Minnesota and Iowa, a part of the later moraine. pee 
HYATT ON THE GENERA OF FOSSIL CEPHALOPODS.— This is an 
elaborate discussion of the character and relations of the genera 
of fossil Cephalopods, the results of many years’ patient study. 
It appears in the Proceedings of the Boston Society of Natural 
History, and is preliminary to a monograph which will appear in 
the Memoirs of the Museum of Comparative Zoology, at Cam- 
bridge, Mass. 
Univalve shells, the author remarks, may be generally spoken 
of as cones, which may be either straight, curved or coiled. The 
larger number of the more ancient shelled cephalopods are 
straight cones. The young of nautilian shells are identical with 
the adults of the curved (arcuate) and coiled (gyroceran) and in 
different series repeat their forms, sutures, shell markings and the 
outlines of their whorl in transverse, section. “ They are in suc- 
cession first arcuate, then gyroceran, and lastly nautilian or close- 
coiled. In several series genetic lines of adult forms may be fol- 
lowed, which lead by gradation from arcuate, cyrtoceran forms to 
close-coiled nautilian shells, the whole showing a connected series- 
of transitions in the form and outline of section, sutures, struc- 
ture and position of siphon, and shell ornaments and apertures, 
In some cases these graded series are in’accord with the chrono- 
logical record, the straight appearing first, the arcuate either in 
company with them or later in time, and the gyroceran and 
nautilian latest.” 
The author adds that we cannot of course claim that such per- 
fect evidence has been found even in the larger number of series. 
