113 



asserting that the occurrence of supernumerary molars in the horse 

 tribe is far from common; and that, therefore, no cases that are met 

 with should be allowed to go undescribed. On this account two 

 additional cases (for both of which I am indebted to my colleague, 

 Professor Dunstan) are made the subject of the present communi- 

 cation. It is much to be regretted that both specimens are fragmen- 

 tary, and consist of only part of the mandible in each case. But in 

 neither of them is the condition of the supernumerary teeth interfered 

 with in any way. Inasmuch as the mandibles are not accompanied 

 by the rest of the skull, it is impossible to say with absolute certainty 

 what the disposition of the upper teeth may have been. But it is 

 always possible to arrive at some conclusion as to the condition of 

 the teeth in an absent jaw, from an examination of the inequalities 

 of the wearing surface on the 

 teeth which are available for 

 inspection. And this is more 

 readily done in connection with 

 the cheek-teeth of the horse 

 than it is with the majority 

 of teeth; for on the equine 

 premolars and molars there are 

 definitely arranged transverse 

 ridges and grooves, from which 

 may be gathered information 

 regarding the number and size 

 of the opposed teeth. 



Case Ko, I (Fig. 1). This |.r 



specimen is in the form of part 

 of the mandible of a horse 

 from which the rami have been 

 cut off immediately posterior 

 to the last tooth. This muti- 

 lation does not, in any way, 

 detract from the value of the 

 specimen so far as the teeth 

 are concerned. On the right 

 side of the mandible the teeth oas, 



Fig. 1. 2)m^ second premolar. 

 m^ third molar (on the right side a, m.a.. 



portion has been broken off = *). ' '^-^ / '^ ^=-"''-^ '^ *• 



m* superniimei'ary molar. 



m, Ä 



Anat, Anz. XXIV. Aufsätze. 



