The Ear 



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Fig. 37 B. 

 FiG.?37. Dermoid Cyst or "Ear Tooth" in Foal. 

 Indicating the method of the formation, from invagination of the epiderm. 

 O, Orifice of invaginated area. FW, Fibrous wall of invaginated canal. 

 EC, Epiblastic cavity. I), Tooth. vST, Squamous temporal bone. 

 ST', ST'^, Incarcerating outgrowths of squamousbone tending to isolate 

 EC from D. GD, Persistent fibrous cord connecting EC with the cap- 

 sule of D ; the epiblastic canal in this cord has been obliterated. PB, 

 Petrous temporal or ear bone, which constitutes a separate bone in 

 the horse. AM, Anditory meatus. MA, Maxillo-mandibular articula- 

 tion. 



