THE NERVUS TEEMINALIS (NERVE OF PINKUS) 

 m THE FROG. 



BY 



C. JUDSON HERRICK. 



From the Anatomical Laboratory of the JJnircrsitij of Chicuyo. 



With Ten Figures. 



A ganglionated nerve connected with the forebrain and inti- 

 mately associated with l^he nerviis olfactorins has been described 

 in nearly all gronps of fishes. The first clear description of snch 

 a nerve is that of Pinkns ('04) for Protopterus. It was termed 

 the nervus tcrmhialis by Locy, in 1905, and accurately described 

 in twenty genera (27 species) of selachians, and it was mentioned by 

 Allis ('97) as occurring in Amia, Brookover ('08) has described 

 it more fully in Amia and Lepidosteus and at the meeting of the 

 Association of American Anatomists in Baltimore, December, 1908, 

 Brookover and Sheldon reported the presence of a similar nerve 

 in the teleosts. Further literature on the subject is cited by the 

 authors mentioned. 



Ernst de Vries ('05) described a transitory ganglion on the 

 vomeronasal nerve of mammals and suggested that the nerve of 

 the organon vomeronasale (Jacobson's organ) of higher vertebrates 

 is homologous with the nervus terminalis of fishes. Since, however, 

 the organon vomeronasale of mammals is lined with sensory epi- 

 thelium of the same type as the undoubted olfactory parts of the 

 nose and gives rise to nerve fibers indistinguishable from other 

 fila olfactoria (Read, '08), it is probable that its innervation does 

 not differ from that of the other parts of the olfactory organ. In 

 this case it is difficult to see how the nerve of the organon vomero- 

 nasale can be compared with the nervus terminalis of fishes, for 

 the latter fibers are not known to connect with the specific cells of 

 The Journal of Compaiiative Neukolouy and rsYCHOLooy. — Vol. XIX, No. 2. 



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