44 PROCEEDINGS OF THE NATIONAL MUSEUM vol.73 



the animals dissected by me. But in some instances the above 

 authorities — especially the former — omitted reference to certain 

 muscles, or grouj^s of muscles, and in other cases the descriptions 

 were so involved as to be obscure. All details of differences are not 

 given, of course, but only those of sufficient degree of quality to be 

 deemed of some importance. The differences in origin and insertion 

 of a muscle in the two animals are not always as great as indicated in 

 the osteological drawings. Thus one investigator might consider that 

 the vastus profundus (fig. 12) arises in Zalophus from only the 

 proximal part of the femur, and in Phoca, in which animal there is 

 slightly more tenacious attachment, that the origin is from the entire 

 shaft, although in reality the muscular difference is very slight 

 indeed. 



As previously mentioned the Zalophus dissected was a juvenile 

 and excessively lean, but its condition of preservation was excellent. 

 The Phoca, on the contrary, was very fat and its condition poor, due 

 in part to rupture of some of the blood vessels, especially about the 

 shoulders, and consequent infiltration t)etween the muscles of blood, 

 the caked condition of which made dissection difficult at times. The 

 coloration of the muscular tissue in these preserved specimens was 

 about the same as in the usual fissiped, but it is common knowledge 

 that the flesh of a freshly-killed pinniped, as well as of the Catacea, 

 is unusually dark. As the flesh of the horse is of a similar color, 

 however, this is not necessarily connected with aquatic specialization. 



It may not be out of place here to mention that the musculature of 

 the Pinnipedia does not differ as greatly from that typical of the 

 terrestrial Carnivora as one might expect from the osteology, and 

 there were but few times when I experienced any difficulty in readily 

 homologizing the musculature to my satisfaction. 



MUSCLES OF THE HEAD 



1. SUPERFICIAL FACIAL MUSCULATURE 



For the reason that Ernst Huber is making a separate study of the 

 facial musculature of both specimens which I dissected, there will 

 be but four of this group mentioned in the present report, this for 

 the reason that they are intimately concerned with functions which 

 it is wished to discuss. 



M. platysma (fig. 15) was extensive in both Zalophus and Phoca but 

 was not otherwise peculiar. 



M. naso-labialis arose mediad of the anterior orbit and near the 

 middorsum of the rostrum, diverging slightly fanwise, and inserting 

 into the mystacial pad. 



M. maxillo-naso-labialis (figs. 4, 5) arose from the zygomatic process 

 of the maxilla caudad of the infraorbital foramen. In the Zalophus 

 there was no osteological indication of origin, but in the Phoca the 



