1897.] Geology and Paleontology. 59 
“Third.—The deposits often occur so high above the surrounding 
region that it is difficult to conceive of the manner in which water 
laden with the fine silt could reach the place of deposition.” 
“ Fourth.—The siliceous and other particles which the loess contains 
are generally angular and often show a freshness of fractures which 
would scarcely appear in particles which had been rolled and washed 
about by the waters.” 
“ Fifth.—The distribution of the loess is better accounted for by the 
consideration of the action of the winds, and by the distribution of the 
forest areas.” 
Mr. Shimek adduces evidence demonstrating (1) that the lcess was 
deposited under climatic conditions essentially the same as those which 
prevail in the same region to-day; and (2) that the deposition was 
slow and continued through a period of considerable extent; and (3) 
that a forest lying adjacent or near to drift covered plains is especially 
favorable to the deposition of lcess. 
The differences between the loess of eastern and western Iowa are in 
accordance with the general topographical and climatic differences 
which probably existed during the loess period, as they do now. 
In considering the time element the author estimates the deposition 
to go on at the rate (minimum) of one mm. a year. If this be correct 
the time required for the formation of the entire deposit would not be 
unreasonably great. (Proceeds. Iowa.Acad. Sciences [1895], 1896.) 
The Extinct Birds of Chatham Island.—The Tring Museum 
is in possession of an immense collection of bird remains from the 
Chatham Islands, consisting of many thousands of bones. The collec- 
tion is being worked up by Mr. C. A. Andrews, and the results pub- 
lished in Novitates Zoologicee. From so large a mass of material Mr. 
Andrews was able to obtain nearly complete skeletons of several of the 
extinct species, and to form a tolerably accurate idea of the degree of 
individual variation in some of them. The first paper on the subject 
appears in the March number (1896) of the publication above men- 
tioned. It comprises a detailed description of the osteology of Diaph- 
orapteryx, prefaced by a brief explanation of the adoption of the gen- 
eric name. In closing he calls attention to its close resemblance to 
Aphanapteryx, and discusses Milne-Edwards’ statement that the simi- 
larity of the two forms is a strong evidence that the islands in which 
they occur, viz., Mauritius and Chatham were formerly connected with 
the great Antarctic Continent. The author is inclined toward Dr. 
