NAUTILUS POMPILIUS. 315 
Memoir is therefore of high importance, in its 
relation to geology ; for it enables us to assert, 
with a confidence we could not otherwise have 
assumed, that the animals by which all fossil 
Nautili were constructed, belong to the exist- 
ing family of Cephalopodous Mollusks, allied to 
the common Cuttle Fish. It leads us further to 
infer, that the infinitely more numerous species 
of the family of Ammonites, and other cognate 
genera of Multilocular shells, were also con- 
structed by animals, in whose economy they held 
an office analogous to that of the existing shell 
of the Nautilus Pompilius. We therefore entirely 
concur with Mr. Owen, that not only is the ac- 
quisition of this species peculiarly acceptable, 
from its relation to the Cephalopods of the pre- 
sent creation ; but that it is, at the same time, the 
living type of a vast tribe of organized beings, 
whose fossilized remains testify their existence at 
a remote period, and in another order of things.* 
rably correct, as far as it goes, is yet so deficient in detail that it 
is impossible to learn any thing from it respecting the internal 
organization of the animal. 
I rejoice in the present opportunity of bearing testimony to 
the value of Mr. Owen's highly philosophical and most admirable 
memoir upon this subject ; a work not less creditable to the 
author, than honourable to the Royal College of Surgeons, 
under whose auspices this publication has been so handsomely 
conducted. 
* A further important light is thrown upon those species of 
fossil Multilocular shells, e. g. Orthoceratites, Baculites, Ha- 
