196 



J. GRAHAM KERR. 



immediately beneath the skin, and just within and parallel to 

 the margin of the lower mandible. As the ganglion tapers off 

 into the commissure, it gives off numerous small and several 

 larger filaments to the skin-fold surrounding the mandibles. 



Fio. 4. 



ant.com 



^Phg 



buc.phar.con 



b.com 



ph.n 



Buccal nervous system of Nautilus pompilius. 



ph.g, pharyngeal ganglion; buc.g., buccal ganglion; c.e, cerebropharyngeal 

 connective; buc.phar.con, bucco-pharyngeal connective; pli.n, pharyngeal 

 nerves; b.com, buccal commissure; ant.com, anterior pharyngeal com- 



From the adoral part of the commissure also some very fine 

 strands pass off to the same structures. 



The internal angle of the pharyngeal ganglion is prolonged 

 towards the middle line into the posterior commissure, which 

 soon swells out slightly, forming the buccal ganglion (buc.g.), 



