68 BRAIN AND BODY OF FISH 



■granular layer of the acustico-lateralis lobe ; this section also shows 

 the cerebellum lying more dorsally and the stratum granulosum 

 joining the above-mentioned granular area. The details of the 

 facial lobe are not very clear in my sections but the motor nucleus 

 of the vagal is well marked. The section also shows the leaf -like 

 structure of the calvula which seems to be almost unique in the 

 neurological world and one is left in wonder at the artistic beauty 

 of the design and the inner hidden meaning of its elaborate arcliitec- 

 ture. 



From the point of view of my argument, we have here a clear 

 relation of the very definite auditory organ with a central acoustic 

 lobe ; as regards the functional significance of the valvula one can 

 only throw out the suggestion that this is a central correlation organ 

 associated with the acoustic, lateralis and olfactory lobes, which 

 appear to be the most important sense organs in the hunting equip- 

 ment of this fish. 



As regards the feeding of Mormyrus there is very little said by 

 the various authorities. But Mr. Michael Graham tells me that 

 Mormyrus kannume on Lake Victoria apparently feeds entirely 

 on insect larvse of 45/45 stomachs containing any food, thirty-three 

 contained blood-worms and there was one record oligochaete ; and 

 one caddis. Its habitat surprisingly included rock and stony 

 bottoms. It is interesting to note that Worthington's observations 

 in Lake Albert and Kioga and elsewhere are similar to those of 

 Graham. 



