IV. 



The Teeth of the Horse. 



ONE of the most interesting of the recent additions to Sir William 

 Flower's instructive " Index Collection " in the entrance hall of 

 the Natural History Museum is a series of jaws of the horse 

 prepared to show the salient features of the dentition at different 

 ages. The series consists of seventeen preparations, ranging from 

 jaws of a half-grown foetus to those of a very old horse of probably 

 not less than thirty-five years. The skulls from which these speci- 

 mens were prepared were collected and presented to the Museum by 



Mr. Thos. Goodall, F.R.C.V.S., an enthusiastic veterinary surgeon, 

 of Christchurch, Hampshire. 



The teeth of the right side of the head are exposed so as to 

 show the whole of their outer surfaces ; but are left in sitil in the jaws, 

 which are widely separated by a space. In this space the teeth of 

 the left side are so placed as to present their grinding surfaces to the 

 observer, the cheek teeth being in most cases shortened by the 

 removal of a part of the root, so as to bring the grinding surfaces 

 down to the level of the external face of the teeth of the right side. 

 In those cases where the milk-molars have not been shed, the under- 

 lying premolars of the left side are placed by the side of their corre- 



