Dunn, Innervation of tJie Thigh in the Frog. 225 



1. Alterations in nomenclature. 



The nomenclature of the muscles has been subject to many 

 changes due to the increase in our knowledge of the general 

 anatomy of the frog, and to the advances in comparative anat- 

 omy. These changes are clearly shown in Table II. 



The division (in Gaupp's edition, Part II, p. 156) of the 

 former M. adductor brevis into three distinct muscles is worthy 

 oi note. The anatomical lines of demarcation are not easily 

 discernible, but the innervation from three distinct sources 

 marks the developmental individuality of the muscles. 



2. Alterations in the account of the innervation. 



In the earlier editions the study of muscle innervation is 

 not at all complete. In the earliest, the edition of 1864, the 

 innervation of the M. sartorius, the M. rectus internus major, 

 the M. glutaeus, and the M. pectineus, is not given. 



In the same edition, p. 45, the innervation of the M. ad- 

 ductor brevis is credited to the crural nerve, v/hile the branches 

 to the M. obturator and the M, quadratus femoris are said to 

 rise together. Haslam, in his revision of 1889, p. 189, repeats 

 these errors. 



Ecker, 1864, in his list of nerve branches, p. 49, does not 

 mention the first branch of the sciatic nerve, the one to the 

 plexus ischio-coccygeus. Haslam's revision, p. 192, supplies 

 this omission, but does not mention the branch to the M. pyra- 

 midahs which Ecker does mention. 



Gaupp, Abtheilung II, Nervensystem, 1897, furnishes in his 

 text no description of the innervation of the M. ileo-fibularis, cor- 

 responding to the descriptions of the branches to the other 

 muscles. In the figure on page 195, the branch in question is 

 represented as the most distal branch of the sciatic nerve, and 

 in the description of the M. ileo-fibularis, Gaupp's edition, Ab- 

 theilung I, Skelet und Muskelsystem, p. 183, the innervation is 

 credited to the sciatic nerve. 



As the thigh of the frog is a most excellent place to prac- 

 tice accurate dissection, it has seemed worth while to give the 

 foregoing description of the nerves and muscles in one of the 



