398 The American Geologist. December, 1894 
1890), to the present area of lake Ontario, has not been definitely traced, 
because the intervening areas arc heavily drift-covered. 
Ii seems probable thai some estimate of the length of the Postglacial 
period may be derived from the rate of recession of theGenesee falls at 
Rochester, as in the similar cases of the falls of Niagara and St. Antho- 
ny. Further light also on this question may be expected from meas- 
urements of the volume of the Genesee gorge above Mt. Morris, with 
consideration of the manner and rate of its erosion by the river. These 
problems may well be recommended for practice in field work by special 
students in geology. w. u. 
The Granites of 'Cecil county in northeastern Mm- aland. By G. P. ("Juims- 
lky. (A thesis accepted for the degree <>f Doctor of Philosophy by the 
Johns Hopkins University, June, 1894. 50 pp., \\ pis., 1894. Published 
originally in the Jour. Cincinnati Soc. Nat. Hist., April and July, 1894.) 
This paper describes the granites of that part of the ancient crystalline 
area of Maryland which lies on the east bank of the Susquehanna river 
and just south of the Pennsylvania line. Toward the north the granite 
comes in contact with the gabbro of the region; here the former rock- 
becomes more basic and in places appears to grade into the latter, but 
elsewhere the granite is seen to be of later date than the gabbro. In- 
gram te is separated into two areas by a belt of staurolite mica-schist; 
the northern (Rolandville) area exhibits striking mineralogical changes, 
the most prominent of which is the extensive development of epidote; 
the southern (Port Deposit) area shows crushing and shearing, and tin- 
rock has become a pronounced granite-gneiss. The belt of staurolite 
mica-schist shows a complete alteration of the staurolite to an aggregate 
of muscovite, chlorite, and quartz. Separation of the heavier constitu- 
ents of the granite soils by use of the ordinary miner's pan, a method 
employed with success by Derby in Brazil and by others, brings to light 
a number of the less common minerals of the parent rock. v . s. g. 
On the Cambrian Formation of the Eastern Suit Range. By Fkitz Noet- 
LINO. (Records of the Geological Survey of India, vol. xxvn, pi. 3, pp. 
71-8G, pi. i, 1894.) 
That there should, to all appearances, be such a dearth of paleontol- 
ogists in the United Kingdom as to compel the government to turn to 
the continent for men of this kind for its Indian Geological Survey, has 
been a matter of frequent comment and some heartburnings. The 
combination of strati graphical geologist and palaeontologist seems, la- 
mentably, to be somewhat out of fashion, and the predominant f ana- 
tomical and phylogenetic palaeontologists among English students may 
have been the principal reason why the Directorship of the Indian Sur- 
vey invited professor W. Waagen, of Prague, and Dr. Fritz Noetling, <<[' 
Strassburg, to undertake its palaeontological work. If the English palae- 
ontologists felt at all "raw" over this, it may have given some of the 
more sinful of them a delicious, if slight, tingle of satisfaction when the 
distinguished German savant described, in the impressive tomes of the 
"Palaeontologia Indrca,' 1 a fauna composed of inarticulate brachiopods 
