À Contribution to the Aiifitomy of Siren lacertinà. (577 



the two main branches — Ramus jugula ris and Ramus m a n- 

 d i b u 1 a r i s. 



Anterior trunk. This trunk is given off after the blending 

 of its ganglion with the Gasserian and consequently contains elements 

 derived from both. It issues from the skull by a comparatively small 

 opening in the petrosal, almost covered by the quadrate and comes 

 out at the floor of the skull, near the edge of the parasphenoid. 

 Almost immediately after its exit it divides into Ramus palatin us 

 anterior and R. alveolar is. 



I. Ramus jugular is. Several muscular branches to the di- 

 gastricus are given oft" from this nerve where first without the cranium. 

 It then passes downwards between digastricus and pterygo-maxillaris, 

 running at first somewhat backward and then directly forward. After 

 passing in a curve around the latter muscle it divides into two branches 

 which spread over the surface of interraaxillaris posterior, supplying 

 it with nervous impulse. 



II. Ramusmandibularis. This branch is wholly sensory. It 

 passes behind and around the quadrate bone to the side of the mandible, 

 where, in company with R. maxillae inferioris V, it runs as far as the 

 symphysis. It supplies sensation (in part) to the lower lip. 



III. Ramus palatin us anterior. This nerve, also sensory, 

 is small in Siren and simple in its course. Having at its origin 

 attained the outer edge of the parasphenoid, it remains in the same 

 relation to this bone, running directly forward immediately beneath the 

 palatal mucous membrane, until it reaches the posterior end of the 

 nasal capsule. It then curves around the parasphenoid and lies at 

 the base of the capsule, just beneath N. nasalis internus. 



IV. Ramus alveolaris. This nerve, shortly after its sepa- 

 ration from the preceding Ramus, divides into two nearly equal 

 branches. One of these runs backward, supplying the palate in this 

 region. As it is nearly as large as the R. palatinus anterior and 

 similar in function, it certainly merits the name of Ramus pala- 

 tinus posterior. The other of the two branches runs forward as 

 R. alveolaris proprius. This runs forwards and downwards 

 across the articulation and reaches the inner side of the mandible. 

 In spite of the definite statement of Fischer to the eftect that it 

 enters a foramen in the mandible, I have been able, neither by dis- 

 section nor by serial sections, to demonstrate such a course. On the 



