274 
THE WASATCH FAUNA. 
head of this section. We observe that species of all the Vertebrate classes 
have been obtained, excepting the Batrachia* Of the Fishes and Reptiles, it 
may be summarily remarked that, with one exception, they do not present 
any marked difference from those at present inhabiting the warmer portions 
of the globe; six of the genera being still in existence. One only of the 
remaining genera belongs, so far as known, to an extinct family; most of 
them being nearly related to living genera. 
The only species of Bird, the Biatryma gigantea, is too little known to 
furnish comparison with living types; but that little indicates considerable 
difference from any of the latter. The Mammalian fauna is much more 
readily understood, and its peculiarities are many. 
The absence of the Carnivora^ Quadrumana, Proboscidean and Buminantian 
of the terrestrial Mammalia^iih large and convoluted brains, may be asserted. 
It is probable that no species of the order Artiodactyla has been found; it 
being exceedingly doubtful whether the only genus that bears a resemblance 
to the Hogs in its dentition ( Phenacodus) has any relationship to those ani¬ 
mals. Of small-brained Mammals, the orders Edentata and Chiroptera have 
not been obtained; in the case of the latter probably owing to the fragility 
of their remains. The distinction between the clawed and hoofed orders is 
generally well marked; three of the former and two of the latter being 
present. Some of the claws preserved present the subungulate character of 
certain existing Bodentia. 
Of the five Mammalian orders above enumerated as present in this fauna, 
but one, the Perissodactyla, belong-s to the large-brained series. This includes 
only ten species of the fifty-four. On the other hand, the remaining orders, 
both ungulate and unguiculate, agree in the very small size of the brain, in 
the relatively small size of the hemispheres to the whole, and in the absence 
or rudimental condition of the convolutions. I have verified this fact in the 
Creodont Oxycena and the Amblypod Coryplwdon in the preceding pages, 
and Professor Gervais has shown the same character in the Creodont Arc- 
tocyon of tlie French Suessonian. 
So far as these observations have gone, they coincide with those made 
* These have been discovered in beds of the Green River series in Wyoming by 
Hayden. 
