126 The American Geologist. Fobruary, i899 
The Cretaceous Foraminifera of New Jersey. By R. M. Bagg, Jr. 
(Bull. U. S. Geological Survey No. 88, 8°, 89 pp., 6 pi., 1898.) Ameri- 
can literature is conspicuously deficient in works relating to the fossil 
Foraminifera, although in Europe the class has received the attention 
of some of the leading paleontologists and their monographs and special 
reports cover the investigations of many years. 
The present memoir covers the Cretaceous Foraminifera from the 
marl beds of New Jersey, including the Monmouth, Rancocas and Man- 
asquan formations. The greatest number of species, (seventy-nine) 
occurs in a limestone layer in the Rancocas formation. Four species 
are common in all four marl beds. Altogether there are one hundred 
and fifteen species now known from the New Jersey Cretaceous. The 
plates give unusually good representations of the form and structure of 
about thirty species of special interest. c. E. B. 
Recent Eart/i Motiement in the Great Lakes Region. By G. K. 
Gilbert. (U. S. Geol. Survey, 18th Ann. Rept., pt. 2, pp. 595-647, pi. 
105, 1898.) 
As has been known for several years, the abandoned beaches of 
the Great Lakes region give undisputed evidence of a decided tilting 
of the land surface in a south-southwesterly direction since the retreat 
of the last ice sheet. Mr. Gilbert has collected the evidence on the 
question, is this tilting still in progress? 
He first calls attention to a paper by Mr. G. R. Stuntz, presented 
before the American Association for the Advancement of Science in 
1870, in which occurs the first broaching of the idea of differential 
uplift in the Great Lakes region. Then the earth movement in this 
district during the closing epochs of the Pleistocene and the reasons 
for regarding a modern change as probable are discussed. After this 
comes a detailed description of the methods used in making measure- 
ments for the present determination. In brief this determination 
is made by comparing the difference of elevation of the water at one 
point of a lake's surface with that at another, as shown by reference 
to fixed bench marks, and then after a period of years another com- 
parison is made to show whether there has been a change in the posi- 
tion of the water surface. The data for these measurements were 
obtained largely from the records of the United States Lake Survey. 
Four pairs of stations were selected, and these, with the years in wliich 
the measurements were made, are as follows: 
Lake Ontario, Charlotte and Sacketts Harbor, 1874 and 1S96. 
Lake Erie, Cleveland and Port Colborne, 1858 and 1895. 
Lake Michigan-Huron, Milwaukee and Port Austin, 1876 and 1896: 
and Milwaukee and Escanaba, 1876 and 1896. 
By reducing the results obtained from these stations to the r.s- 
sumed direction of the tilting (S. 27' W.) and eliminating as far as 
possible all sources of error, it was found that the tilting amounted 
to 0.42 foot per one hundred miles per century. This is the mean 
of the determinations. Concerning the question at issue the author 
savs: 
