194 'Journal of Comparative Neurology and Psychology. 



distance lying partly enclosed by the tractus olfacto-lobaris medialis. 

 When the anterior commissure is reached, however, it turns ab- 

 ruptly mesad (Fig. 5) and largely decussates in the mid-line (Fig. 

 G) in the most rostral part of the commissure. Part of the 

 libers apparently do not cross but end on the same side. The exact 

 termination of the fibers could not be demonstrated. It is certain, 

 however, that they end close to the mid-line, without doubt in the 

 dense nucleus of small cells shown in Fig. 7. 



x\s was stated in the earlier report, it should be noted that the 

 connection between the central tract and the peripheral ganglion 

 with its fibers has not been established and cannot be except by for- 

 tunate Golgi or Cajal preparations. There can be little doubt, how- 

 ever, that this is the nervus terminalis for the following reasons. 

 The ganglion and peripheral distribution of the fibres are identical 

 with the condition found by Brookover in Amia and Lepidosteus 

 in connection with what is undoubtedly the nervus terminalis. It 

 is also similar to that described for Protopterus by Pinkus, for 

 Ceratodus by Sewertzoff and for selachians by Locy. The course 

 of the central tract' corresponds to that shown for the nervus ter- 

 minalis of selachians by Locy, who worked out the central termina- 

 tion in some detail. Still stronger support comes from the findings 

 of Herrick in the frog. In this form the neiwe takes the same 

 course through the brain, including the decussation. Peripherally, 

 however, the nerve leaves the brain to run in the meninges rostrad 

 past the formatio bulbaris so there can be no question as to its char- 

 acter. 



Summarizing: there is little doubt that there exists in the carp 

 a nerve comparable morphologically to the nerve of Pinkus or the 

 nervus terminalis of other fishes and the frog. 



Hull Laboratory of Anatomy, 

 The University of Chicago, January 18, 1909. 



