THE INFRA-ORBITAL TRUNK. 187 



of this point and of the edge of the lower lip, to the 



extreme tip of the mandible. 



Terminal buds are abundant near the mandibular teeth 



and mesally of them, but not laterally of them in the 



regions supplied by the fibres of this nerve, and I believe 



that none of these fibres are destined for these sense 



organs but that they are all of a general cutaneous nature. 



One branch, however, enters the alveolar canal of the 



dentary bone. Here it turns mesad and a part, if not all, 



of its fibres emerge again to supply the skin of the tip of 



the mandible near the middle line. It is probable that 



none of them innervate the tooth pulps, as these have a 



separate innervation from the r. mandibularis intemus 



VII. 



5. — The M. Adductor Mandibul(E. 



This muscle is innervated in Menidia by several 

 branches of the r. mandibularis V in the way typical for 

 teleosts. The only exceptions to this arrangement known 

 to me are Esox, as described by Vetter ('78, p. 496) and 

 Lota, as described by Goronowitsch ('96, p. 41), who find 

 that this muscle receives in addition to these fibres a small 

 twig from the r. mandibularis VII. This needs confirm- 

 ation and I may add that an attempt to trace by dissection 

 a cutaneous nerve like luy first twig of the r. mandibularis 

 VII for the sense organ 0.6 might easily lead to such a 

 conclusion, for the fibres pursue a tortuous and often 

 branched course through the m. adductor mandibulae and 

 might easily be lost by the dissector before their emer- 

 gence upon the skin. 



6. — The Dorsal Division. 



The dorsal division of the infra-orbital trunk contains 

 all of the r. maxillaris V and a portion of the r. buccalis 



