On the Gnathodon beds around the head of Mobile Bay. 173 
The residue of these remains belong to terrestrial mammals, birds, 
fish, and reptiles. The two former, consisting only of a few 
broken and rather indeterminate fragments in a somewhat super- 
ficial situation, may without impropriety be regarded as the spoils 
of hunting. But the next class, pertaining to fish, were un- 
doubtedly, with very few exceptions, contemporaneous with the 
formations where they occur. For with the exception perhaps 
of a small portion of the superior part of the remains in question, 
they are scattered more or less abundantly through the entire 
mass in stich a manner as to render it evident that they found 
their way there by no artificial process. For the exuvice of each 
animal occur in separate and distinct masses, more or less com- 
plete,—scales, vertebrae and all. 
In one instance no inconsiderable portion of the vertebral col- 
umn of a large species was found deposited in a connected form 
in the interior of one of these shell masses, just as other analo- 
gous remains occur in ancient formations when they have not 
been exposed to disturbing causes. 
Some of the species which have been obtained are of more 
frequent occurrence than others, and these are precisely the kind 
which might have been expected to be found with these remains, 
such as the Sargus ovis and an unknown species of Sparus (?). 
The strong pavement of palatal teeth which these fish possess 
enables them to feed on the T'estacea in question, whose shells 
they crush with facility. Besides these, species of Perea, Breme, 
There are also considerable quantities of drifted alluvium, logs, 
&c., which have been discovered at various depths, both in the 
recent and more ancient alluvial deposits. But these lead to no 
very definite conclusion. And the subjacent sands and clays, so 
far as observed through the whole series, bordering upon the 
Water courses, even to the outcropping of the white limestone, 
are equally destitute of organic distinctions. It is however very 
