TEMPORARY DENTITION 



395 



indicate the age of one year. The corner incisors, completing the number 

 of six, begin to protrude through the gum, as does also the fourth molar 

 behind the three pre-molars, and at the age of one year the front and back 

 of the mouth will present the appearance of the drawings (figs. 605, 606). 



So far as the appearance of the incisor teeth is concerned, it will be 

 noticed that it closely coincides with that of the mouth of the horse at five 



Fig. 606.— Molar Teeth of Colt at one year 



years old (fig. 613). The prominent difference, however, is that all the teeth 

 are temporary in the one case and permanent in the other. The presence 

 of the tusks, or in their absence the existence of six permanent molars, 

 in the five-year-old horse, will prevent any mistake being made as to the 

 animal's age. It has already been stated that in the case of forest ponies 

 an error in regard to the animal's age is quite possible unless the difi'erence 

 between temporary and permanent teeth is recognized. 



Fig. 607. — Molars of Colt at two years 



Between one year and two years of age the only change in the incisor teeth 

 is that which is naturally consequent on growth of the teeth and the wear 

 of the upper surfaces by attrition. At the full age of two years the upper 

 surfaces of all the incisor teeth are worn flat, and the tables, which is the 

 name given to the worn surface, are fully formed, which means that there is 

 a complete line of wear running round the central cavity (infundibulum or 

 mark). Occasionally there is an exception in the posterior or inner edge of 

 the corner tooth, the wear of which is not quite complete. 



