ElvISHA MITCHELL SCIENTIFIC SOCIETY. 13 



hiternal oblique. The muscle arises along- its ex- 

 ternal border from the superficial lumbar fascia, di- 

 rectly beneath the origin of the external ohlique\ and 

 from the ventral margin of the ilium. At its poste- 

 rior end the muscle arises from the pubis. 



The fibres run anteriorly and ventrally. At some 

 distance external to the rectus abdominis, they pass 

 into a thin aponeurosis, which throughout its anterior 

 extent is firmly attached to the underlying (/. e. dorsal) 

 trajisversalis abdonmiis, and is thus dorsal to the rec- 

 tus abdominis . Throughout its posterior extent the 

 aponeurosis extends ventrally over the rectus abdom- 

 inis, being- indisting-uishably united v^ith the aponeu- 

 rosis of the external oblique. 



At its anterior end, near the dorsal border, the mus- 

 cle is attached directly b\^ its fibres to the last rib. 

 The muscle may here be seen to be a continuation of 

 the layer formed by the interyial intercostals. The in- 

 ter7ial intercostal between the 12th and 13th ribs, is 

 in fact directly continuous with the internal obiique. 



Synonymy. Oblique-interne abdominal, S.-D., vol. 

 II, p. 315; internal oblique, M., p. 142; internal oblique. 

 G. & T., p. 29. 



Mivart is wrong- in stating the muscle to be "insert- 

 ed inside the cartilag-es of the last ribs." Gorham and 

 Tower inexactly state "the more anterior fibres to be 

 inserted on the cartilages of the ribsS' According- to 

 Strauss-Durckheim the relations of the aponeurosis of 

 the internal oblique to the rectus are quite the same as 

 in human anatomy, in that anteriorl}^ the aponeurosis 

 splits into two layers which ensheathe the rectus dor- 

 sally and ventrall}^ This ventral limb of the anterior 

 part of rectus sheath, if it ever is present, must con- 



