CRANIAL NERVES OF SILURUS AND MORMYRUS 41 
VII nucleus is due to the small development of the secondary 
taste system. 
The ventro-lateral migration of the frontal cells sf the IX 
column (containing probably VII and IX cells) is more pro- 
nounced than in most other teleosts. 
Regarding the sensory roots, I may emphasize the fact that 
Silurus glanis, like the North American siluroid fishes examined 
by C. J. Herrick, exhibits a considerable hypertrophy of the 
sensory branchial system, especially of the sensory VII, which 
by means of the ramus recurrens facialis innervates the taste 
buds of the body. In contrast with cyprinoids, the sensory 
system of the [X and X nerves is not so much hypertrophied. 
According to Herrick this is chiefly due to the absence of the 
palatal organ, which in cyprinoids contains an enormous number 
of vagal taste buds. 
In Mormyrus, contrary to the statements made by Sanders 
and Franz, the sensory system of the branchial nerves is very 
poorly developed; but the lateralis nerves, especially the posterior 
ones, attain a size which is much more conspicuous than in siluroids. 
The development of the lateralis system has given rise to the 
formation of what Sanders has called the tuberculum impar 
faciale and the vagal lobes (loc. cit., p. 51), but which really are 
the lateralis lobes of both sides fused in the dorsal mid-line. 
The conclusion which Herrick (who had no material of Mormyrus 
at his disposal) has drawn from the erroneous statements pub- 
lished by Sanders (viz., that the hypertrophy of the lateral lobes 
of the valvula cerebelli in Mormyrus are due to their relations with 
the centers of taste) consequently has to be discarded.* 
It seems to me that Herrick’s own researches already made 
this supposition improbable. The sharp delimitation of the 
visceral and somatic sensory centers, so often demonstrated by 
Herrick himself, holds also good for the brain of Mormyrus, in 
43 The argument used by this author, that the fishes here under consideration, 
unlike most other vertebrates, make somatic movements in response to cutaneous 
gustatory stimulation, does not seem convincing to me, and moreover has not 
been proved for Mormyrus. 
