552 Recent Literature. [July, 
mathematical astronomer. Zodlogy will, in consequence be more 0 
an exact sclence and possess more real interest and value in the 
eyes of the masses than it now does. 
The chapters on the influence of light and of temperature are 
particularly suggestive. So is the fifth chapter, on the influence 
of stagnant water, which embraces the results of the experiments 
of Schmankewitsch on the brine shrimp; also those of Semper on 
the effect of changes in the volume of water on the pond snail. 
The portion which is quite novel, and which will attract gener 
attention, is Semper’s theory of the origin of coral islands. !e at- 
tempts to show that the connection between the strength and di- 
rection of ocean currents, and the vigor of growth in the corals and 
in the reefs they form, is one of the principal causes that have 
given the reefs their frequently very remarkable forms. This view 
is, he claims, in direct contradiction to Darwin’s theory of subsi- 
dence, as well as Dana’s theory. It is more of a piece with Mose- 
ley’s theory recently proposed, although it is not impossible that 
Darwin’s, as well as Dana’s, on the one hand and Moseley’s and 
Semper’s on the other, may all be the terms of a series of causes. 
he book teems with facts which will be new to most of out 
readers, and hence it is a solid contribution to the evolution theory. 
Compared with Oscar Schmidt’s crude and one-sided presentation 
of Darwinism, in his little book entitled Descent and Darwinism, 
Semper’s will remain a classical work, from its basis of well- 
grounded facts. 
Without careful search for errors we notice that under the head 
of hybridism several cases known in the United States among the 
deer and Salmonidz are not referred to (perhaps they were ee 
d- 
gular Branchipod genus Thamnocephalus cannot be said to occur 
in the “ South of the Union,” for its only known habitat is Kansas, 
on the eastern edge of the Rocky Mountain plateau. We notice a 
few typographical errors, and the index is too short and quite de- 
fective. 
Anniversary Memoirs oF THE Boston SocreTy OF NATURAP 
History.—Following the example of German scientific societies; 
