62 COMPARATIVE ZOOLOGY. 
they are the chief organs of prehension ; in the carnivo- 
rous tribes they are thin and retractile; wlile in the 
Whale the upper lip falls down like a curtain, overlap- 
ping the lower jaw several feet. Asa rule, the mouth is 
terminal; but in the Elephant, Taptr, Hog, and Shrew, 
the upper lip blends with the nose to form a proboscis, or 
snout. The mouth is comparatively small in the Elephant 
and in gnawing animals like the 
Squirrel, wide in the Carnivores, 
short in the Sloth, and long in 
the Ant-eater. Teeth are usual- 
ly present, but vary in form and 
number with the habits of the 
The Ant-eater is tooth- 
less, and the Greenland Whale 
has a sieve made of horny plates. 
The tongue conforms in size and 
shape with the lower jaw, and is 
animal. 
a muscular, sensitive organ, which 
ee 
her 
Fie. 25.—Human Tongue and ad- 
jacent parts: a, lingual papillee ; 
b, papille forming V-shaped 
lines; d, fungiform papille; e, 
filiform papille; g, epiglottis; 
m, wvula, or conical process, 
hanging from the soft palate, 
n; o, hard palate; 7, palatine 
glands, the mucous membrane 
being removed; v, section of the 
lower jaw. 
lines with mathematical precision. 
serves Inany purposes, assisting 1n 
the prehension, mastication, and 
swallowing of food, besides be- 
ing an organ of taste, touch, and 
speech. Its surface is covered 
with minute prominences, called 
papille, which are arranged in 
In the Cats, these are 
developed into recurved spines, which the animal uses in 
cleaning bones and combing its fur. 
occur on the roof and sides of the mouth of the Ox and 
other Ruminants. The tongue is remarkably long in the 
Ant-eater and Giraffe, and almost immovable in the Gnaw- 
ers, Elephants, and Whales. 
8. The Teeth of Animals.—Nearly all animals have 
certain hard parts within the mouth for the prehension or 
Similar papillee 
