145 

 prepared ; but with all care the unfortunate animal 

 becomes emaciated, and is speedily consigned to the 

 knacker. Fortunately, however, the molars are not 

 often irregular in their growth. In fact, most ir- 

 regularities of the teeth must be carefully sought for, 

 but one form which is not rare by any means ought 

 to be always observed. In certain animals the lower 

 jaw is so short, that the creatures cannot place the 

 incisors together or in apposition : the consequence 

 is, that the lower incisors being active instruments, 

 have to perform their functions at considerable dis- 

 advantage ; but, nevertheless, they act and receive 

 wear. The upper incisors, however, are, in such 

 mouths, subjected to little attrition ; the corner, and 

 a portion of the lateral nippers alone, meeting each 

 other; hence the central nippers, which grow more 

 forward than they ought, at length project down- 

 wards, and overhang those of the lower jaw. This 

 arrangement of the incisors constitutes what is called 

 a " parrot mouth," because of the resemblance which 

 the teeth bear to the bill of the bird. Most old 

 horses are more or less parrot-mouthed ; but young 

 horses also occasionally exhibit mouths of this des- 

 cription, and in these last it is certainly a defect, for 



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