The Lateral Liue System in Siluroids. 



545 



branch which proceeds into the suprascapula towards the shoulder- 

 girdle (branch to pore 7 in Clarias and Auchenaspis, 8 in Chaetostomus). 



Organ 9 in Auchenaspis corresponds to organ 20 in Amia and 

 in the former a branch proceeds medianly and backwards to 

 pore 8 and corresponds to the rudimentary canal re- 

 presented in Amia by the dorsal line of pit organs, 

 a complete canal in Polypterus. 



Comparing the mandibular line of Auchenaspis and Amia one can 

 only affirm that the 5 organs in the former generally represent the 

 10 in the latter. In the preoperculum organs 15 and 16 of Amia 

 are not represented in the Siluroids. 11 and 12 qï Amia are supplied 

 by one branch of the nerve and may correspond to 6 of Auchenaspis 

 and 13 and 14 of the former would then probably correspond to 

 7 and 8 of the latter. 



The canal of the interoperculum of Chaetostomus is not represented 

 in Amia, unless it can be regarded as the rudimentary proximal portion 

 of a canal represented in Amia by the gular line of pit organs. 



