as indicative of the Age of the Animal. 
347 
that many pigs have been objected to and excluded from com- 
peting for prizes for which they could have legitimately con- 
tended. Opinions of their age have been based almost entirely 
on the amount of the development of the tushes, and when these 
teeth have happened to be either large or early formed, the 
animals have been put aside as being above the age stated in the 
owner's certificate. 
The improvement of our several breeds of pigs has of late 
received very properly much attention, and the result has been 
that we now possess several breeds which not only vie with 
each other in the rapidity with which they arrive at maturity, 
but also in beauty of form, and aptitude for early fattening. 
We have therefore, as in cattle, to investigate these causes of im- 
provement, with a view to determine tlieir effects on the dentition 
of the pig — or rather, perhaps, to master the facts which apper- 
tain to the teething of our established breeds. There exists, as 
we have seen, amid great diversity of opinion, but little on which 
we can rely ; still, however, it is necessary to give the statements 
of other writers upon this interesting subject. 
The most lengthy description of the dentition of this animal 
with which I am acquainted — but nevertheless, from its numerous 
errors, a very unsatisfactory one — is the one given by Mr. 
Youatt. He says, in hjs work on 'The Pig,' quoting from 
Girard's ' Traite de I'Age du Cochon,' 
*' Tliat the hog is born with two molars on cacli side of the jaw. By the time 
he is three or four months old, he is provided with his incisive milk teeth and 
the tushes ; the sujiernumerary molars protrude between the fifth and seventh 
month, as does the first back molar; the second back molar is cut at the age 
of about ten months ; and the third generally not until the animal is three years 
old. The upper corner teeth are shed at about six or eight months, and the 
lower ones at about seven, nine, or ten months old, and replaced by the per- 
manent ones. The milk tushes are also shed and replaced between six and ten 
months old. The age of twenty months, and from that to two years, is 
denoted by the shedding and replacement of the middle incisors, ot pincers, in 
both jaws, and the formation of a black circle at the base of each of the tushes. 
At about two years and a half or three years ol' age, the adult middle teeth in 
both jaws protrude, and the pincers are becoming black and rounded at the 
ends. After three years the age may be computed by the grovi th of the tushes ; 
about four years, or rather before, the upper tushes begin to raise the lip ; 
at five i\\ey protrude through the lips ; at six years of age the tushes of the 
lower jaw begin to show themselves out of the mouth, and assume a s])iral form. 
These acquire a prodigious length in old animals, and particularly in uncastrated 
boars, and as they increase in size they become curved backwards and outwards, 
and at length arc so crooked as to interfere with the motion of the jaws to such 
a degree that it is necessary to cut oft" these projecting teeth, which is done 
with the file or with nippers." * 
Such is the history of the dentition of the pig in the principal 
work we possess on this animal, which with the opinions of 
* Youatt on the Pig, p. 71. 
