142 CAUSES, SYMPTOMS A>fD TREATMENT OF 



true of the molar teeth, those of the upper jaw being more widely 

 separated, and nearly square in shape. The molars generally have 

 two infundibulae. The cutting of teeth in the foal varies some, 

 with which the period of gestation has something to do. If the 

 foal is born sooner than natural they may not appear so soon, but 

 there are generally twelve molars and four incisors at birth, or if 

 not at birth they will appear in about fourteen days. The twelve 

 molars appear as temporary, the others as permanent teeth. The 

 teeth are divided thus : — The two occupying the centre are called 

 central, the two next — one on either side of these two— are called 

 the lateral, the last two on either side are called the corner. So at 

 birth the foal usually has two central incisors ; in about seven to 

 nine weeks the two lateral are cut ; in from seven to nine months 

 the third pair of incisors, and at one year the corner teeth are in 

 wear ; at twelve months the first permanent molar is up and in 

 wear, so we have them thus : 



Incisors. Molars. 



Age. Temporary. Permanent. Temporary. Permanent. 



At or soon) , ^ 2 



after birth/ ^ " ^^ " 



1 year 12 12 4 



2 years 12 12 8 



3 " 8 4 4 16 



4 " 4 8 24 



5 " 12 24 



In ponies you may mistake temporary for permanent teeth. At 

 about two years and nine months the central incisors appear; at 

 three, they are up and in wear ; at three and a half the lateral teeth 

 appear ; at four they are up and in wear. At four years old the 

 horse has a full mouth of permanent molars. It is a good plan for 

 you to recollect the time when the teeth make their appearance, 

 and become familiar with the difference between the milk and per- 

 manent teeth. The milk teeth are whiter, and present a pretty 

 distinct neck. 



The teeth are alongside of each other, forming an oblong or para- 

 bolic arch, and are designated the superior and inferior dental 

 archers, interrupted by the interdental spaces in the horse, but in 

 some animals the teeth are continuous. There are three classes of 

 teeth : incisors, canine and molars ; then there are two sets of teeth ; 

 temporary and permanent. All the incisors and twelve molars ap- 

 pear as temporary teeth. The body of the tooth has an encircling 

 ring of enamel, then dentine and then a central ring of enamel. In 

 this centre there is a black mark. The infundibulum disappears as 

 the animal grows older. It is usually filled with tartar or food, 

 and is surrounded by enamel. The teeth grows to a great extent 

 from tbe pulp. But after this is destroyed, they receive support 

 from the surrounding structures. In the molar teeth there are two 

 or three of these pulp cavities. At an early period of gestation the 

 teeth appear as a small depression in the mucous memljrane of the 

 gums, called the primitive dental groove. Then, in from twelve to 

 fifteen weeks (in the human being), a little prominence takes place, 

 and this is called the papillary stage ; then these papillae become 

 separated from each other and form along by the side of each other, 

 and prolongations pass across between the different papilla, and 

 they develop a follicle or bag ; this is called the follicular stage. 



