368 F. L. LANDACRE 



ance of the taste buds seems much more in accordance with the 

 facts. 



A good deal of interest attaches to the dorsal extension of the 

 epibranchial ganglion. There is nothing in its composition or 

 mode of development to indicate that it is formed otherwise 

 than by the extension dorsally of the epibranchial placode. 

 If, however, there are lateral mass cells in this ganglion they must 

 enter into its composition at this point, and for this I find no evi- 

 dence. 



Herrick ('01) states that he finds no fibres derived from this 

 ganglion except gustatory or special visceral, and since there is no 

 evidence that cells other than those derived from the epibranchial 

 placode enter into its composition we are driven to the conclusion 

 that the epibranchial placode furnishes those cells which give rise 

 to gustatory fibres and that those cells which give rise to general 

 visceral fibres in the IXth ganglion of other species must come from 

 the lateral mass or from the neural crest. 



The evidence for the presence of general visceral fibres in the 

 IXth nerve is exactly like the evidence for the presence of lateral 

 mass cells in the ganglion. Neither has been detected. There 

 is a possibility of both having been overlooked, of course, but if 

 they should be found to be present it would not in my estimation 

 affect the conclusion drawn. It would simply fall short of a dem- 

 onstration. The fact that the Vllth, IXth and various portions 

 of the Xth ganglia possess gustatory fibres approximately in 

 proportion to the extent to which the epibranchial placodes con- 

 tribute cells to these ganglia materially strengthens the conclu- 

 sion. The geniculate ganglion of the Vllth has a well defined 

 lateral mass contingent, as was shown in describing this ganglion. 

 That portion of the visceral Xth from which arise the large visceral 

 rami is almost exclusively derived from the lateral mass, contain- 

 ing only small contingents from the reduced fifth and sixth epi- 

 branchial placodes. The number of gustatory fibres derived from 

 this ganglion is correspondingly small. 



The third and fourth epibranchial ganglia possibly contain 

 small constituents from the lateral mass. These ganglia, however, 



