THE STRUCTURE OF THE TEETH G5 



portion pressed upon gradually disappears ; it is absorbed, 

 taken up, and carried away by numerous little vessels, 

 whose office it is to ^et rid of the worn-out or useless parts 

 of the system. This absorption continues to proceed as the 

 second teeth grow and press upon their predecessors, until 

 the whole of the fang is gone, and the crown of the tooth, 

 or that part of it which was above the gum, having no 

 longer firm hold, drops out, and the second teeth appear, 

 larger and stronger, and permanent. In a few instances, 

 however, the second teeth do not rise immediately under 

 the temporary or milk-teeth, but somewhat by their side ; 

 and then, instead of this gradual process of absorption and 

 disappearance from the point of the root upwards, the root 

 being compressed sideways, diminishes throughout its whole 

 bulk ; the crown of the tooth diminishes with the root, and 

 the whole is pushed out of its place, to the forepart of the 

 first grinder, and remains for a considerable time, under 

 the name of a wolf's tooth ; causing swelling and soreness 

 of the gums, and frequently wounding the cheeks. These 

 would be gradually quite absorbed, but the process might 

 be slow and the annoj^ance would be great ; therefore it 

 is proper to get rid of these diminutive teeth, either by 

 punching them out or drawing them as soon as they are 

 perceived. 



Three Years Old. — At three years old the two centre horse- 

 teeth are so defined in their appearance — indeed, so well- 

 grown — as to be unmistakable. The superior length and 

 squareness over the colt or milk-teeth is manifest ; outside, 

 too, they are darker in colour, the new coating of the stony 

 covering (crusta petrosa) being only partially removed at 

 the front edges. At "three off " the side milk-teeth are 

 shed, and horse-teeth take their places. In our drawing 

 of a three-year-old mouth this has not yet occurred ; 

 but the inflammation of the gums, visible, though it 

 does not appear painful to the animal, shows itself. 

 The milk-teeth are finally shed about the seventh 

 month after the completion of the third year, those 

 of the lower jaw coming out fir.^t. It is often asked, 

 Cannot this mouth be given to a forward two-year-old ? 

 We are told so ; and here is the process, which we insert 

 for what it is worth. The central nippers are punched or 

 drawn out, and the others appear three or four months 

 earlier than they otherwise would (?). In the natural 



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