MUSCLES OF THE ANTEI7T0Ii EXTREMITY. 93 



95. j\I. extensor diy. Ill pro/jrius. 



Dugès, sus-luno-phalangettien du médius, n. 12 2. 



This muscle has two heads of orig-in, from the os naviculare and 

 lunatum. These form one musenlar belly, which rapidly diminishes 

 and passes into a tendon ; this, after receiving- a few muscular 

 fibres from the second metacarpal, runs to the outer part of the 

 dorsal surface of this fing-er as far as the terminal phalanx, where it 

 is inserted. 



96. il/, extenmr (Jig. IV xiropriuH. 



Dugès, sus-pyro-phalangettien de l'annulaire, n. 128. 

 By a somewhat broad base, this muscle arises from the oh navi- 

 culare and hmattmi. The tendon receives fibres from the fourth 

 metacai-pal and runs on the outer half of the dorsal surface of this 

 fing-er as far as the middle phalanx, where it is inserted. 



(III.) MM. inferosHei. 



97. 98. [a.] MM. IranHversi mctacarpi (Ecker), (Fig. 78 I, t' , a(h). 

 These lie transversely between the metacarpals. There are three ; 



the first has been already described as ni. addnclor (VkjUI 11 (n. 73); 

 the second is stretched between the third and fourth metacarpals, 

 and the third between those of the fourth and fifth fing-ers. 



99, 100. 101. [b.] M3I. intero-^Hei volareK. 



One may reg-ard as such, four long-, thin muscles, which take 

 orig-in near one another on the palmar surface of the carpal bones, 

 and diverg-e from this towards the second and fifth fing-ers. 



1. The first of these muscles (Fig-. 78/^2') has already been 

 described above as the m. flexor digiii 11 tert'ms (n. 72). 



1. The second (Fig-. 78 ^3) passes from the orig-in already de- 

 scribed to the palmar surface of the basal phalanx of the third 

 fing-er. 



3. The third (Fig-. 78 iâ^) runs, in like manner, to the fourth 

 finger. 



4. The fifth (Fig. 78 is) to the fifth finger 1. 



102 to 108. MM. interossei dorsalen. 

 These arise in common from the metacai-pals, and are inserted 

 into the basal phalanx of the corresponding surface on the finger. 



' Whether these muscles may be regarded as mm. interosi'ei is open to discussion, 

 .as they appear to act more as mm. opponente-i. 



