94 THE SALAMANDER 



is inserted. It is quite distinct from the M. intertransversarius 



capitis superior. 



The M. intertransversarius capitis inferior (Gaupp, in the Frog) is 

 really the direct continuation of the subvertebral musculature and 

 arises from the transverse process of the second vertebra. It is 

 inserted over the ventral surface of the occipital region of the skull, 

 and is separated from the superior portion of the intertransversarius 

 muscle by the first spinal nerve, and is necessarily antagonistic to it. 



Innervation: In general the dorsal trunk muscles are innervated 

 from the dorsal rami of the spinal nerves. 



Function : Their general function is to produce a lateral flexion of 

 the spine by alternate contraction on either side. The portions of the 

 muscle attached to the skull similarly turn the head from side to side. 



3. Ventral Trunk Muscles. 



The muscles on the ventral side of the sulcus lateralis comprise two 

 distinct series, the one — the rectus group — with fibres running 

 parallel with the body axis, and the other — the oblique muscles — 

 whose fibres are at an angle with this direction. 



It is not easy to give synonyms for these muscles, since there 

 is some variation among the different genera of Urodeles in which 

 they have been investigated. The reader should, therefore, refer to 

 Maurer's paper for a detailed comparison, but the following may be 

 quoted as applying to Salamandra. 



Funk (1827) calls the whole rectus muscle, including the M. 

 rectus cervicis, the M. hyoideo-ypsiloideus. Carus (1828) dis- 

 tinguishes the superficial from the deep portion and calls the former 

 abdominis musculus rectus (8), and the latter M. epischio-hyoideus (7). 

 He does not distinguish the 'cervical' from the 'abdominal' portions. 

 Rymer Jones (1852) refers to the superficial portion as the Rectus 

 abdominis and to the profundus portion as the M. pubo-hyoideus. 

 He also does not separate the rectus cervicis and rectus abdominis 

 muscles. Owen (1866) also calls the deep portion the M. pubo- 

 hyoideus, while Hoffmann (1873-8) describes a muscle as the M. 

 pubo-thoracicus (Rectus abdominis) which appears to represent the 

 superficial portion of the muscle only, the profundus portion being 

 undescribed. Hoffmann further distinguishes the M. ypsiloideus 

 posterior as the M. pyramidalis. 



M. rectus abdominis superficialis (m.r.ab'.). Maurer (i 892). 



This portion of the rectus muscle forms a large flat sheet covering 



the ventral parietes of the abdomen, the right and left halves being 



