


X 
REVIEWS. 665 
Mr. Lyman shows below, the Caribbean fauna in undisputed possession 
of the Atlantic side, with outlying species on the Pacific shores 
o Cretaceous forms occupy the depths, and Tertiary genera the mid- 
dle ground of the coast on the Pacific side, and if so, what are the rela- 
tions of these facts to the geological history of North America? 
These are a few of the questions which pea themselves and which 
can only be answered by farther investigati 
ve 
our own expeditions have not obtained specimens from 
such deep ge us the "o ħave been none the less interesting. 
It was announced by Professor L. Agassiz at the last meeting of the 
American fase BHR that it was the intention of the Superintendent of 
the Coast Survey to carry out other lines of sounding from the Atlantic 
side and still others from the Pacific 
The enlightened spirit of appreciation ax the present needs of science 
—Ó in o expeditions of the Coast Survey, and the great impor- 
tance of sou s they have already attained, promise to accomplish as 
mu EN for the progress of Natural History in this country as ae have 
hitherto As that of Geography and the Physical History of the sea. 
Part IV. contains a ** List of Star-fishes, which, thougn rang oa is 
depths of from five to one hundred and seventy-four fathoms, present an 
ünexpected departure from iini was offered in other dredgings." 
“ With the exception of the Pte "et and cd deeeqprivcit acti detiene the bathymetrical 
and geographical distribution of ssi star 
Mr. Lyman's report* on the Ophiuridæ a: Astrophytidze shows that 
all the new types of these families are found only below one hundred 
fathoms. Seven of these new genera are und at length. Mr. Ly- 
man's conclusions are confirmatory of those published by Mr. Agassiz; 
he, however, does not seem prepared to go quite so far. 
In showing that there are obstacles in the way of the hypothesis that 
the Gulf of Mexico and the Pacific were joined x a strait across what is 
now the Isthmus of Panama, the author asks a very pertinent question. 
Why do we not find Pacific forms on the bade i side? The evidence 
all goes to show that there has been a migration of species from the 
Caribbean to the Pacific, but none from the Pacific to the Caribbean. 
This objection has already been partially answered, as we have remarked 
above, by investigations upon the Tertiary shclls and corals of the West 
. Indian Islands 
Count Kont report t gives us a descriptive list of the Crinoids. 


suus M, Bulletin or The Museum of Comparative Zoology. Re port on the "ripae and 
e Pourtales. 

Assistant, U Uu 8. Coast Survey. Prepared | by Theodore re oe 
, No. 11 eee of Crinoia obtained on the 
of Florida and Cuba, by the United States Coast Survey, Gulf Is, in 
eo gsi By L. F. de Pourtales, Assistant, U. S. Coast Survey, pp. 
AMER. NATURALIST, VOL. III. 84 


