io8 THE SALAMANDER 



tibial spine, passing between the MM. extensor digitorum com- 

 munis and extensor cruris tibialis in order to do so. Both sections 

 are narrow, oval in cross-section, and of medium strength. 



Authors have homologized this muscle in different ways. 

 Humphry and Mivart, in Cryptobranchus, and Noble in the 

 Salientia, regard it as composed of two distinct muscles. De Man, 

 in Triton, regards any separation into two sections as artificial. 

 Perrin, in Salamandra, describes it as one muscle with two heads, 

 while Appleton — whose name is adopted here — in his list of muscle 

 homologies (Part II, pp. 434-5) calls it M. extensor iliotibialis, and 

 distinguishes the two heads as pars anterior and pars posterior^ while 

 the same author in another place (Part I, p. 378, fig. 2) labels the 

 former section Ilio-tibialis, and the latter Ilio-extensorius, thus 

 following Noble. 



Innervation : From N. extensorius. 



Function : True extensor of the leg. 



M. ilio-fibularis (m.il.f.). de Man (1873); Sieglbaur (1904); Osawa 

 (1902); Appleton (1928). 



Semimembranosus ....... Funk (1827) 



Wadenbeinbeuger ..... 

 Ileo-peronien ..... 



Abductor fibularis primus 

 Ileo-peroneal ..... 



Biceps flexor cruris (outer or ilio-fibular sector) 

 Deducteur du fibula (i 13) 

 Ilio-femoro-fibularis .... 



. Meckel (1828} 



. Duges (1834), 



Stannius (1854-6), 



. Mivart (1869) 



Humphry (1872) 



Perrin (1892) 



Low (1926) 



Together with M. femoro-fibularis = 



Ileo-femoro-fibularis (biceps) .... Hoffmann (1873-8). 



Most authors regard this muscle as the long head of a biceps 

 femoris muscle. The validity of this is doubtful, and the question 

 will be discussed in detail after the description of what is regarded 

 by these authors as the short head, namely, the M. femoro- 

 fibularis. 



The M. ilio-fibularis arises from the external face of the ilium, 

 posterior to the M. extensor ilio-tibialis. It passes down the postero- 

 dorsal border of the thigh to its tendinous insertion on the proximal 

 end of the fibula. The N. peroneus passes over its dorsal edge at its 

 insertion. It is a relatively weak muscle. 



Innervation : From N. extensorius. 



Function: In conjunction with the M. extensor ilio-tibialis it 

 would tend to extend the leg, but acting with the M. pubo-tibialis 



