as indicative of the Age of the Animal. 
351 
of size adapts its cusps to fit between those of the upper molar 
teeth. 
Fig. -IV.* 
Fig. 48.t 
At three months two more temporary incisors are added to 
mch jaw, making, exclusive of the fecial corner teeth, four in the 
loicer jaw, as represented in fig. 48, wherp these teeth are marked 
L. I., signifying lateral incisors. The full number of temporary in- 
cisors is now complete, and the jaws 
when examined seem to be fairly filled 
■with teeth. The middle incisors, as 
well as the foetal corner teeth, and also 
the temporary tushes and molars, are 
by this time sufficiently grown, and the 
young animal can be safely left to 
" shift for himself." No difficulty can 
exist in judging of the age of the pig at 
this date : ' first dentition,' as it has 
been called in medical language, being 
perfected. 
From three to six months the size 
of the teeth increases with increasing 
age. At about six months the temporary 
incisors of the lower jaw, which are always longer but nai-rower 
than those in the upper jaw (see fig. 45), will likewise have at- 
tained their greatest length. After this period the incisors will 
begin sensibly to diminish in length from daily attrition. The 
* Fig. 47. Skull of the pig, one month old, showing, in addition to the foetal 
teeth H. I., the middle incisors ; and t. m,, the temporary molars. 
t Fig. 48. The anterior part of the lower jaw of a three months' old pig, 
showing the fcetal and the temporary teeth. M. i., middle ; L. I., lateral incisors, 
2 A 2 
