162 REVIEWS AND BOOK NOTICES. 
currents, by the tides and prevailing winds, are more varied of 
course than those of the rivers. The action of the sea extends 
over a great area and acting at a great depth is the most powerful 
agent in the rearrangement and final distribution of the materials 
brought down by the rivers. 
The action of internal agents produced by eruptions, though 
undoubtedly very powerful, is unfortunately inaccessible and we 
can only guess at what might happen from a study of such phe- 
nomena as the submarine volcanoes of the Mediterranean, the 
Caspian sea, and remember that many of the phenomena which 
produce instant visible changes onthe surface of the globe must 
be acting with equal or greater efficiency and as frequently on the 
bottom of the sea. 
The agency of organisms in determining the constitutions of the 
bottom of the sea is only introduced as far as the action of the 
invertebrates of the coast of France can throw any light upon 
the subject, and no attempt has been made by the author to do more 
than point out, what is well known to all students of marine zool- 
ogy, thé correlation between the fauna and the physical structure 
of the coast. He indicates the dependence of special forms or cer- 
tain floras upon a sandy or rocky bottom, or a gravelly shore, or 
the different features presented by a muddy shore. This is per- 
haps the most unsatisfactory part of the work, and it is a great 
pity that the description of the agency of animal life upon the 
formation of the sea bottom should have been limited to the com- 
paratively uninfluential agencies at work at the present time on 
. the coast of France, and that only slight allusion should have 
been made to the all-important part which corals now play in the 
fashioning of the sea bottom of so large a part of our globe. 
The maps are admirably engraved and as far as they relate to 
_ France and Europe of great accuracy. A few unfortunate errors 
have crept in relating to the hydrography of the Hudson and Sus- 
quehanna rivers and the connection of the great Lakes, which are 
= undoubtedly due to the want of supervision of a part of the work 
during the Prusso-French war. The map of the iyami 
„basins of France is especially worthy of notice. He has com- 
„pleted the survey of the seas of the present time by a very suc- 
cessful attempt to restore and map out the ancient seas and gen- 
eral topography of France during the successive geological 
* 
ds, and ta gire a succinct ses of the nanen ace have 
