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bulletin: museum of comparative zoology. 



digits. This divides into four tendons, two large and two small ; the 

 two large ones, after passing through the sheaths formed by the perfora- 

 tus, are inserted into the ungual phalanges of digits three and four ; the 

 two smaller tendons are attached similarly to the second and fifth digits. 

 As regards the innervation of the normal manus, we need concern our- 

 selves with the condition of the median nerve only, by which the digits 



-fix. jicrf/ 



.rHx.perf. 



Fig. I. — Left normal manus of pip, showing flexor muscles, fix. ptrf., tendons of 

 flexor perforatus; fix,, ptrf ., flexor perforans. i natural size. 



are chiefly supplied. The trunk of the median nerve (Fig. J, n.m.) 

 passes between the two flexor muscles at the carpfil joint ; nearly at a level 

 with the proximal ends of metacarpals ii and v it gives off two lateral 

 branches (2, 5) to supply these digits. The main nerve, continuing dis- 

 tally, soon separates into two large branches (3, 4), ■which pass 

 together along the region between digits in and iv, to which they 

 are distributed. The lateral branches (2, 5) before pa-ssing to their 



