AET. 15 ANATOMY OF THE EARED AND EARLESS SEALS HOWELL 93 



The much simpler adductors of Phoca may be termed as follows : 



Adductor anticus (figs. 11, 12, 24) was a small muscle next caudad to 

 the pectineus and of about the same size. Origin was from the border 

 of the pubis and insertion was mediad to that of the pectineus upon 

 the shaft of the femur, but there was no appreciable osteological 

 indication of the fact. 



Adductor posticus (figs. 11, 12, 17, 24) was a very broad sheet of 

 muscle arising from the caudal half of the pubic border and over 

 the lateral surface of all of the ischium save the more caudal por- 

 tion. It converged to an insertion that was largely tendinous upon 

 the prominence upon the femur just laterad of the trochanteric fossa. 



Murie indicated that there were six adductors in Emne.topias. As 

 already mentioned, his adductor brevis primus is the true pectineus, 

 and what he termed pectineus is my adductor 5. I am unable to 

 determine the exact number of adductor divisions in Arctocephalus 

 but judge that conditions were ver}^ similar to those in my Zalophus. 

 ^liller wrote that the adductors are absent in Phoca, but it is evi- 

 dent that he mistook the two adductors for the obturator externus 

 and did not dissect deeply enough to encounter the latter muscle, 

 restricted as it is in this genus. 



MUSCLES OF THE LEU 



M. gastrocnemius (figs. 12, 26, 27, 28) was single in the Zalophus and 

 arose from the well-defined ridge upon the medial epicondyle of the 

 femur and the capsule of tlie joint. It crossed to the outer side of 

 the shank and developed a tendon (first upon its medial border) 

 which was inserted upon the calcaneum. In the Phoca this muscle 

 was double. The iiiedialis was very heavy, w^ith fleshy origin from 

 the caudal surface of the well developed medial epicondyle. An 

 internal tendon developed upon which the fibers from both bellies 

 of the muscle inserted. The tendon narrowed and was attached 

 to the calcaneum. The lateralis was not one-tenth the size of the 

 medial division. It arose by a slender tendon from the lateral epi- 

 condyle of the femur, and joined the tendon of the medial division 

 distad of the muscular part. 



M. plantaris (figs. 12, 25, 27, 28) in the Zalophus was about one-third 

 the size of the gastrocnemius. It arose from the lateral epicondyle 

 of the femur in very intimate relation wdth, and between, the popli- 

 (eus and peroneus longus. It passed deep to the tendon of the gas- 

 trocnemius, over the groove upon the medial calcaneum, and thence 

 to the plantar fascia. With care two layers of this w-ere dissected 

 free. The more superficial divided into four tendons between the 

 five digits, and each of these again divided, the branches running 

 to the borders of the adjoining digits. The deeper layer also sepa- 

 rated into four branches, these constitutinjr sheaths for the flexor 



