IRREGULARITIES OF THE DENTAL APPARATUS. 753 



The horse does not always place himself in the same conditions in 

 order to crib : he takes or does not take a point of contact. In the latter 

 case, it is said that he cribs in the air, or that he is a wind-sucker. We 

 will not occupy ourselves with this here. (See Viciom Habits.) 



When the horse cribs by taking a point of contact with his teeth, it 

 is evident that the latter should present abnormal characters which 

 vary in a very great degree, according to the mode of cribbing and 

 the nature and form of the bodies which are seized between the 

 jaws. 



Sometimes, in fact, the animal chooses the bottom of the trough, 

 the free border of the manger, the internal edge of this border, the 

 lower cross-piece of the hay-rick, the strap or rope to which he is 

 fastened ; at other times it is the window-sill, the border of the stall, 

 if he be loose in the stable ; the end of the shafts, that o the pole of 

 the wagon, the harness of a neighboring horse, or any other body in 

 his reach, if he be harnessed to a wagon. 



More rarely, he cribs upon himself, upon one of his members, for 

 example ; or, again, he cribs by contact and in the air alternately ; 

 finally, sometimes, the point of contact is simply taken by the lips or 

 by the tuft of the chin ; in this case the teeth will, of course, not show 

 any abnormal wear. 



But, whatever may be the mode of contact, or the incisors upon 

 which it is effected, this wear is constant in all cases in which the jaws 

 are in contact with bodies of wood, leather, metals, stone, etc., capable 

 of cutting them in consequence of the repeated frictions. 



After having fixed the jaws, the animal makes a guttural "clucking" 

 sound more or less strong, which many persons liken .to that caused by 

 belching, but which to us appears to be exclusively a grunt or sound 

 occasioned by effort : immediately after this the air descends towards the 

 stomach. Our researches upon this point, as well as the analyses of the 

 gas in the digestive apparatus, induce us to believe that, in the generality 

 of cases, the subjects actually swallow the air. Many persons, on the 

 contrary, think that there is an eructation of gas through the mouth, 

 consequently true belching. We have not been able to verify this 

 latter fact, although we have spent entire days with cribbing horses. 



However this may be, it follows from our special observations of 

 cribbing, 1 that the varieties of wear which result from it can be classed 

 in one of the five following categories : 



1 Goubaux et Barrier, Des irregularity's dentaires resultant de 1'usure produite par le tic ; in 

 Bulletin de la Socie'te' centrale de me'decine v6terinaire, seance du 10 Novembre, 1881, et Archives 

 v6terinaires, 1882, p 13. 



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