COMPENDIUM OF GENERIC DISTINCTIONS. 
AXPLANATION OF SIGNS AND TERMS. 
TEETH, 
TIncisors.—These are the teeth which are placed in the 
front of the jaw. They are inserted in the premaxillary 
bones, and in the corresponding portion of the lower jaw. 
They are termed “incisors,” or cutting teeth, from the Latin 
word incidere, which signifies “to eut,” even though their 
edges should not be formed for cutting. 
JANINES.—These teeth are situated next to the incisors, 
and are inserted at or close to the suture of the premaxillary 
bones in the upper jaw. In the lower jaw, the canines are 
set opposite to those of the upper jaw, and when the mouth 
is closed pass in front of the crowns of the upper canines. 
They are called ‘‘canines,” from the Latin word canis, a dog, 
because they are largely developed in the dogs. 
PR#MOLARS.—These teeth are situated behind the ca- 
nines, and next to the true molars. The word “‘ molar” is 
derived from the Latin mola, a mill, because these teeth 
serve to grind the food. Popularly they are called “grinders.” 
In human subjects the premolars are sometimes termed the 
“‘bicuspids,” on account of the double cusp on their sur- 
faces. 
| 
Mo.ars.—These teeth are permanent, and are situated 
behind all the others. They are often not developed until 
comparatively late in life. 
The DENTAL FORMULA is a concise mode of describing the 
number and positions of the various teeth, and is easily com- 
prehended, The accompanying formula is that of Man :- 
12=2 ¢ J) p 22 w 83 2 32 
ei 0 aes 
In these formulas the upper figures refer to the teeth of the 
upper jaw, and the lower line to those of the lower jaw, 
while the short hyphen — serves to separate the right from 
the left side. In man, therefore, there are two incisor teeth 
| on each side of the upper jaw, and the same in the under 
jaw; one canine on each side of the upper jaw, and the same 
in the lower jaw ; two premolars on each side of the upper 
jaw, and the same in the lower; three molars on each side 
of the upper jaw, and the same in the lower: in all, thirty- 
two in number. The dentition is always presumed to be 
| that of the adult animal, 
CLASS IL—MAMMALIA. 
ANIMALS possessed of vertebree ; breathing atmospheric 
air by lungs; heart with two auricles and two ventricles ; 
blood warm and red; producing living young; nurturing 
them by milk, which is secreted in the ‘mammary glands ;” 
skin coyered with hair, spines or scales. 
Order.—BIMANA. 
Hands and feet five-fingered, the nails all flat and broad. 
All the teeth even and close to each other, the molars 
equally enamelled. In this order there is but one species, 
namely Man,—Homo sapiens. 
2-2 1 
Teeth.—I. poe Oa 
Order.—_QUADRUMANA. 
Hinder feet five-toed, the thumb opposable to the others ; 
fore-feet sometimes four-fingered, the thumb being absent. 
Molar-teeth equally enamelled; with one exception, the 
Cheiromys, they possess incisor, canine, premolar, and 
molar teeth. Skin covered with hair, with the exception 
of the palms of the hand, the face, and the callosities of 
the hinder quarters. Mammi placed on the breast. 
Family. SIMtad%, 
Teeth.—Molars, a the false molars being tuberculate. 
Nails rather flat or slightly rounded, and not pointed like 
claws. Fore-feet almost always five-toed. ‘Thumb opposable. 
Tail never prehensile. 
Genus.—Troglodftes. 
2 
T} 
Teeth.—I. 
2 ool -p 22 y 338 
2 3 
Il’ "2-2 *3 
Canines slightly elongated, and placed close to the in- 
cisors. 
Head.—Muzzle rather short—Cheek-pouches none—Ears 
large and projecting. 
Tail.—None. 
Huabitat.—Western Africa. 
32, 
