2. Note on the Occasional Occurrence of the Musculus Rectus Thoracis in Man

Extract

During the last winter session, I communicated to the Society a paper on the “Musculus Sternalis,” in which I argued that the longitudinally arranged muscle, occasionally found superficial to the sternal fibres of origin of the pectoralis major, was not, as anatomists have usually described it, homologous with the anterior or thoracic fibres of the mammalian rectus, but belonged to another group of muscles.

Since that time I have met with two subjects in the dissecting-room, in each of which a longitudinal muscle occurred, lying in contact with the outer surface of the anterior extremities of the upper true ribs, and beneath the fibres of the pectoral muscle, which is, from the position, direction, and connection of its fibres, I believe to be regarded as homologous with the thoracic end of the mammalian rectus.