THE 



Ohio Journal of Science 



VUBMSHKD BY THE 



Ohio Statk T'ntvkrsity Scientific vSociety 



Volume XVII DKCKMBER, 1916 No. 2 



TABLE OF C O N T E N T vS 



Okey— The Relation of the Profundus and Gasserian Ganglia in the Embryo 

 of the Urodele, Plcthodon glutinosus 25 



CoNDiT— A Shelf of Geologic Literature for the Small Library, with a Guide 

 to the More Important Reports on Ohio 52 



McCoRD— Government Documents and the Public Librarian 6S 



Smith — Boric Acid Occurring Naturally in Some Foods 66 



THE RELATION OF THE PROFUNDUS AND GASSERIAN 



GANGLIA IN THE EMBRYO OF THE URODELE, 



PLETHODON GLUTINOSUS. 



Katherine W. Okey, 

 Department of Anatomy, Ohio State University. 



Introduction. 



In such lower fishes as the Selachians both a profundus 

 and a Gasserian ganglion are present as separate ganglia in 

 the adult form. Many ganoids and all teleosts, with the 

 single recorded exception of Trigla, show modifications of the 

 condition in Selachians, by the apparent loss of the profundus 

 ganglion or by its fusion with the Gasserian in the adult. 

 (Allis. '97). Likewise in every adult form of Amphibia so far 

 described the Gasserian is the only ganglion on the trigeminus 

 nerve. No separate profundus ganglion is present, although 

 rami from the Gasserian ganglion are homologized with all or 

 portions of the ramus opthalmicus profundus found in 

 Selachians. 



The assumption has been made that the profundus ganglion 

 has in the Amphibia fused with the Gasserian to form what 

 Coghill ('02) calls "a fused ganglionic complex" in which 

 rami representing both of the ganglionic components have 

 their origin. Evidence for the proof of this specific assumption 



25 



