Further observations on the medulla oblongata of cyprinoids ; and a comparative study of the medulla of clupeoids and cyprinoids with special reference to the acoustic tubercles

In a previous paper (Evans, 1931) an endeavour was made to correlate the feeding habits of Cyprinoids with the conformation of the medulla oblongata, and it was concluded that the Cyprinoids can be divided into three main groups. It was found:- (1) That the vagal lobes are large in the Carps, the Goldfish and the Bream and that these are all mud feeders. (2)That the vagal lobes and the facial lobe are small in the Roach, the Rudd, the chub and the Dace, all of which take a fly and feed largely by sight. (3)That the facial lobe is large in the Gudgeon, the Barbel and the Tench. The Facial nerve in this group, all of which possess barbles, divides into two branches after entering the medulla oblongata. The Gudgeon and the Barbel grope and grub for their food and never take a fly.