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of the m. velo - quadratus, and the other to the lateral part of that 

 muscle and also to the m. velo-spinalis. 



After giving off this velar branch, the motor nerve continues later- 

 ally forward and downward along the ventro - mesial surface of the 

 pterygo - quadrate, there lying partly buried in the lateral surface of 

 the truncus maxillo-mandibularis. A large bundle of motor fibres is 

 here sent to the ramus mandibularis. After sending this bundle of 

 fibres to the ramus mandibularis the remaining part of the nerve joins 

 and accompanies the sensory part of the ramus maxillaris, lying at 

 first ventral and then ventro - mesial to it. This sensory part of the 

 nerve has already separated into two or three bundles of fibres, and 

 as they pass across the ventral surface of the palato - coronarius and 

 then forward along the lateral surface of that muscle, the motor nerve 

 either passes upward between them and the m. palato - coronarius or 

 pierces that muscle; in either case gradually acquiring, as the nerves 

 reach the anterior end of the palatine, a position dorsal and mesial 

 to the sensory nerves. In its course up to this point it sends one or 

 more branches to the m. copulo - quadratus profundus, which lies im- 

 mediately external to it, and others to the m. palato-coronarius, which 

 lies internal to or is traversed by it. It also sends a branch to the 

 m. copulo-palatinus, this branch having peculiar relations to the sen- 

 sory part of the nerve. In one of the two series of sections in which 

 it could be traced it ran outward between the branch destined to ten- 

 tacle 4 and the united branches destined to tentacle 1 and tentacle 3 , 

 lying dorsal to the former and ventral to the latter. It then turned 

 downward and forward external to the branch to tentacle 4 , and went 

 to the mesial surface of the muscle it innervates. In the other series 

 it had a similar general course, but it passed outward between the 

 two parts of the nerve to tentacle 4 . In both series the nerve might 

 be taken for a branch of the nerve to tentacle 4 , almost as well as for 

 a branch of the motor nerve. Müller says that the muscle is inner- 

 vated in B. heterotrema by the nerve that goes to what he calls the 

 2nd and 3rd tentacles. 



Having passed beyond the anterior end of the palatine, and there 

 lying between the cornual cartilage externally and the lateral labial 

 cartilage internally, the motor nerve sends a large branch upward in- 

 ternal to the cornual cartilage. This branch separates into several 

 branches and innervates the m. palato-ethmoidalis superficialis, the two 

 muscles that together form the m. palato-ethmoidalis profundus, the 

 m. tentacularis posterior and quite undoubtedly the m. nasalis also, 

 but the innervation of this last muscle could not be established 



18* 



