176 



Tliis much as regcards the mammals, which I have considered 

 somewhat more extensively as most, and to my mind the most 

 accurate, investigations have been done on them. 



1 can be brief about (he birds, reptiles, and amphibians. 



There does not seem to be much known about the N. Terminalis 

 in the birds. 



In the fro<j it was found in 1909 by C. Judson Herrick, 

 who also described its central termination more especially ; its 

 peripheral branches could not be traced accurately. This was also 

 the case in the Urodela, where the nerve was observed by Mr. Kibbkn 

 (1914), who could not however tind any ganglionic cells in it. Some 

 time later .Iohnston succeeded in this. He says "In Amblystoma the 

 nervus terminalis is ganglionated and supplies the vomeronasal organ, 

 as in reptiles and mammals", (.'oncerning the reptiles he says that 

 the j)eripheral termination takes place "in the turtle to a medial 

 diverticulum of the nasal sac, which presumably cori-espoiids to the 

 vomeronasal organ or a pai-t of it". 



We now come to the fislies wherein, setting aside an isolated 

 observation by G. Fritsch about one of the Selachii, the nei-ve was 

 (Irst found by Pinkus in Protopterus. His preliminary communication 

 appeared in 1894 in the "Anatomischer Anzeiger" and was followed 

 in 1895 by his elaborate treatise "Die Hirnnerven des Pi-otopterus 

 annectens" in the "Morphologische Arbeiten". Pinkus found that his 

 new nerve originates in the brain, places itself lostrally against the 

 most mesial bundle of the olfactory nerve, takes its course over the 

 nasal mucous membrane and is to be followed to the roof of the 

 anterior nasal o[)ening. The nerve consists of nonmedullated fibres 

 and has in its course a cellular swelling, which is undoidttedly the 

 Ganglion Terminale of later writers, although Pinkus could not 

 convince himself of the ganglionic nature of the cells. 



Skwkrtzokf (1902) found the nerve in embryos of Ceratodus. He 

 mentions the fact, of importance for the homologisation, that the 

 nerve does not branch in the olfactory mucous membrane and that 

 it terminates in the skin at the external nasal opening. Soon (1904 — 

 1905) BiNG and Buhckhardt described the nerve in the adult Cera- 

 todus also. 



Concerning the Selachii the treatise of Locy, which appeared in 

 the "Anatomischer Anzeiger" after several smaller publications, is 

 well known. In this treatise, which is accompanied by a large number 

 of handsome illustrations, he described the structure and development 

 of the nerve in Acanthias as seen in series of sections, as well as 

 its course as this is to be seen, by means of the dissecting microscope. 



