The appendicular muscles of Necturns maculosus. 403 



two portions (fu') is very short; its fibers run obliquely outwards- 

 and wrap themselves about the olecranon, inserting into the side 

 of this process and upon the shaft of the ulna beneatli it. 



The second or raain portion (fu) is somewhat fnsiform, and is 

 longitudinal in direction. It lies along the outer edge of the entire 

 shaft of the ulna and tapers down into a terete tendon, which termi- 

 nates on the outer, or marginal, aspect of carpale 4 + 5, but seems 

 to be also prolonged along the margin of the carpus, to a further 

 insertion into the ulnare-intermedium. 



M. flexor radialis (fr). This muscle forms, upon the other 

 side of the antebrachium , the counterpart of the preceding; like 

 the latter, it determines a part of the contour of the forearm, yet 

 is a somewhat shorter muscle. It arises from the medial condyle 

 of the numerus upon its radial side and inserts by fleshy fibers into 

 a broacl area which includes both the distal end of the radius and 

 the radial half of the radiale. 



M. pronator (pr). The fibers of this broad muscle run obli- 

 quely across the antebrachium from a more proximal ulnar to a 

 more distal radial Position. It is thus directly coincident with the 

 supinator of the other side; that is. if the paw were semi-transpa- 

 rent, and were held up to the light, the two muscles would be 

 superimposed one upon the other. The pronator arises from the 

 middle of the shaft of the ulna by a narrow line, running lengthwise 

 and just within (radial to) the lines of origin of the ulnaricarpalis 

 and the inner half of the palmaris profundus. It inserts by two 

 slips, the one into the proximal side of carpale 2, the other into the 

 radial side of the base of metacarpale II. Corresponding tho these 

 two insertions the muscle is incompletely divided into two sheets, 

 of which the deeper one is inuch the smaller, and makes its inser- 

 tion into the carpale, while the bulk of the muscle inserts into the 

 metacarpal, and forms an abductor of digit II in precisely the same 

 way as does the supinator on the extensor side. 



Mm. flexores breves superficiales (fbs). These are a 

 series of short fleshy bundles, covering the metacarpals of the sepa- 

 rate digits; after the removal of the skin they are seen in part 

 upon either side of the digital slips of the palmar fascia, They are 

 capable of Separation into distinct elements mainly through their 

 insertions, so that the mass supplied to each digit is a bündle of 

 more or less separate slips rather than a Single muscle. They all 

 arise from the dorsal (inner) surface of the palmar fascia, partly 



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