THE MUSCLES 99 



the hind-limb as well as the arm, as also does that of Sieglbaur ( 1 904). 

 McMurrich (1904) made a study of the phylogeny of the crural 

 flexors and their nerves, and, while he does not deal expressly with 

 Salamandra, his work is of sufficiently general nature to have a bear- 

 ing on the problems involved. Most of his observations were made 

 on serial sections, and this has caused him to draw one or two con- 

 clusions which scarcely seem justified when viewed in the light of 

 actual dissections. These conclusions are criticized by Ribbing 

 (1909) and will be referred to again later. Ribbing's work is very 

 sound and has the advantage that the results are correlated with those 

 obtained for the fore-limb. More recently a phylogenetic study of 

 the muscles and nerves of the post-axial region of the tetrapod 

 thigh has been undertaken by Appleton (1928), who describes the 

 condition found in the Salamander, while Low (1926—9) has studied 

 the development of the pelvic girdle and its muscles in a number of 

 Urodeles (but not Salamandra) and throws some light on the 

 phylogeny of certain muscles. 



2. Muscles of the Pelvis and Thigh (PI. VIII, figs. 48 and 49). 



On removing the skin from the ventral surface of the pelvis and 

 the base of the tail the following three muscles may be observed. 

 They are grouped together by Appleton as the Caput ventrale^ M. 

 flexor cruris. 



M. pubo-ischio-tibialis (m.p.i.t.). de Man (1873); Osawa (1902); 

 Low (1926). 



Rectus ........ Funk (1827) 



Gracilis cruris flexor (35) ..... Carus (1828) 



Zweiter Beuger Meckel (1828) 



Sous-ischio-tibial ....... Duges (1834) 



Flexores abducentes ..... Stannius (1854-6) 



Depressor and Adductor of the pelvic limb . . Owen (1866) 



Gracilis Mivart (1869) 



Superficial stratum of Plantar muscles of Thigh (Gracilis +Semitendino- 

 sus+Semimembranosus) .... Humphry (1872) 



Pubo-ischio-tibialis (Semitendinosus) . . Hoffmann (1873-8) 



Flechisseur du tibia (i lo-i i) ..... Perrin (1892) 

 Rectus femoris ....... Eisler (1895) 



This is the most superficial muscle of the pelvis as seen from the 

 ventral side. It arises just lateral to the pubo-ischiadic symphysis 

 and covers the M. pubo-ischio-femoralis externus with the exception 

 of a narrow strip anteriorly. It passes right down the ventral surface 

 of the thigh and is inserted on the tibia. It is wide and thin at its 



