INTRODUCTORY REMARKS. 
At the present day there is considerable difference among systematic zoologists as to the 
characters of the primary divisions among the Mammals, and the points upon which their classi- 
fication should be based. For my present purposes, however, I adopt the following arrangement: 
A.—UNGUICULATA, (with claws.) 
1, TEETH OF THREE KINDS. 
a. Mamme two, on the breast. 
I. Quadrumana. Limbs free; hind feet acting as hands. 
II. Cheiroptera. Arms provided with a naked membrane for flying. 
b, Mamme more than two: on the belly. 
Ill. Rapacia. Mamme free. 
IV. Marsupialia. Mammez contained in a pouch. 
2. TEETH OF LESS THAN THREE KINDS. 
V. Rodentia. Canine teeth alone wanting. 
VI. Hdentata. Incisor teeth, sometimes canines and molars, wanting. 
B.—UNGULATA, (with hoofs.) 
VII. Solidungula. With one hoof. 
VIII. Pachydermaia. With two hoofs. 
IX. Ruminantia. With more than two hoofs. 
C.—PINNATA, (with fins.) 
X. Pinnipedia. With four fins, 
XI. Cetacea. With two fins. 
Of the above orders all are found in North America except the Quadruwmana; and although 
the Solidungula, represented by the horse, do not now exist as native animals, yet there are 
abundant evidences of the existence of the horse as an extinct genus, as well as of other forms 
of the order. 
Although large collections of Cheiroptera or bats were made by the surveys, I do not propose 
to work them up in the present report, owing to lack of time necessary to do it properly. The 
same may be said of the Pinnipedia and Cetacea. 
1L 
