192 PROCEEDINGS OF THE AMERICAN ACADEMY. 



which dorsal roots are wanting." He refers, however, to the fact that 

 an indication of a dorsal root for the first spinal was found by Kingsley 

 ('92, p. 678) in Amphiuma and by Mrs. Gage ('93, p. 275) in the larva 

 of Diemyctylus. 



In Spelerpes the two roots of the second spinal nerve unite into a 

 ganglion, from which were traced a dorsal {rm. d. spi.^) and a ventral 

 branch (h^gls.). The former has been represented as entirely motor, 

 because no general cutaneous fibres were actually demonstrated, although 

 the nerve could always be followed to the narrow space between the 

 dorsal muscles and the overlying skin. The ventral branch is the hypo- 

 glossus nerve, which runs cephalad and supplies m. sternohyoideus and 

 m. genio-hyoideus. 



Von Plessen und Rabinovicz ('91, p. 20) describe the hypoglossus in 

 Salamandra as a branch of the first cervical. No dorsal root was found, 

 but they describe and figure a ganglion connected with the dorsal branch. 

 Kingsley ('92, p. 678) mentions the persistence of the dorsal ganglion 

 as a noticeable feature in connection with the twelfth nerve. 



