THE ANATOMY OF A HAMMERHEAD SHARK. 981 



The liyomandihular branch of the seventh nerve runs posterior 

 to the mandibular branch of the fifth and gives off an external 

 mandibular. 



The auditory nerve has already been described in relation to 

 the membranous labyrinth. 



Summary. 



The following are the important points dealt with in the 

 paper : — 



1. The skull, except the jaws, has been described in detail. 



2. The membranous labyrinth has been described and figured 

 for the first time. 



3. The existing accounts of the macroscopic structure of the 

 brain have been revised, and notes have been included on the 

 relationships of most of the cranial nerves. 



Literature. 



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1872. 



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Haia." Journ. Anat. & Physiol, vol. xvii., 1883. 

 13. Miklucho-Maclay^ — Beitrage z. vergl. Keur. d. Wirbelthiere. 

 I. Das Gehirn. d. Selachier. Leipzig, 1870. 



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 Proc. Zool. Soc— 1922, No. LXYI. 66 



