of the Pelvic Plexus in Acanthias vulgaris. 



9 



II. Variations in the Number of the Post-girdle Nerves. 



A considerable amount of variation occurred under this head, and 

 the amount shown by the two sexes differs the number in the male 

 being greater than in the female. The results may be tabulated as 

 follows : 



Tabl III. 



From this table it appears that there is a greater caudal extension 

 of the fin innervation area in the male, which amounts to 1 39 meta- 

 mere. It has, however, already been seen that in the male the pelvic 

 girdle is on the average 82 metamere, more rostrally situated than 

 in the female. Consequently the nett caudal preponderance of the fin 

 innervation area in the male over that in female amounts to 1 39 - 

 0'82 = 0'57 metamere. 



III. Variations in the number of Nerves forming the Collector. 

 Table IV. 



This table shows that, whilst the number of the nerves forming th 

 collector is subject to a considerable amount of variation, there is a 

 striking agreement in the average number of collector nerves in the 

 two sexes. 



