174 



THE NERVOUS SYSTEM. 



[Gaskell has proved that this nerve contains both sympathetic and 

 vagal elements, and that it is therefore really a vago-sympathetic.] 



The branches 



Fig. 1 1 6. 



VN vn' 



Xl-8 



IV 



and communica- 

 tions of the pneu- 

 mogastric nerve 

 are : 



a. Communica- 

 tions between the 

 ganglion of the 

 pneumogastric and 

 the sympathetic 

 system (Fig. 1 1 1 

 Sp], which again 

 connect it with 

 the Gasserian gan- 

 glion of the tri- 

 eminal nerve 



Right half of skull of Rana e.iculenta, seen from within. 



// Optic nerve. 



/// Motor oculi nerve. 



IV Trochlear nerve. 



VN Hoot of the trigeminal nerve. 



Vp Gasserian ganglion. 



VS Sympathetic nerve. 



VI Abducens nerve. 



T//1 Facial nerve. 



VIII Auditory nerve. 



A"i-3 Pneumogastric and glossopliaryngeal nerves. / gee sympathetic 



system). 



b. [The Ramus cutaneiis dorsalis (Fischer) is considered by Stan- 

 nius and Fiirbringer to be the homologue of the Ramus atiricularis 

 it passes outwards between the digastricus and temporalis to be 

 distributed in the skin of the suprascapular region. This nerve 

 is the persistent portion of the N. lateralis nervi vagi of the 

 tadpole.] 



c. During its course over the petrokyoidei the vagus gives off a 

 few twigs (Fig. 114 pp], which form a fine plexus to supply these 

 muscles and the pharynx [also a twig to the trachea, according to 

 Hoffmann]. 



d. The Ramus accessories (Fiirbringer, Hoffmann, Ecker), (Fig. 

 114X7) is usually a single small nerve which runs between the 

 intertransversarii muscles and the trapezius : it supplies the under 

 surface of the latter muscle. 



e. The Ramus scapular is (Hoffmann) is a very slender nerve arising 

 near the Ramus accessor ius ; it passes along the under surface of 

 the trapezius to the inner surface of the interscapularis, which it 

 supplies. 



