PART III. 

 BRAIN OF ELEPHANT SEAL AND OF WALRUS. 



The Brain has been examined and described in only a few species of the Pinnipedia. 

 As might naturally be expected, the brain of the Common Harbour Seal, Phoca vitulina, 

 is the one which has most frequently attracted attention, and descriptions, often 

 undoubtedly very brief, but in many cases illustrated by figures, have been given by 

 Tiedemann, Vrolik, Daubenton, Cuvier, Leuret, Bellingeri, Owen, Broca, Krueg, Mivart, 

 and Theodor. Rosenthal has written a short description of the brain of Halichcerus 

 grypus. Mivart has made a few observations on some of the convolutions of the brain of 

 Cystophora cristata. Murie has written an elaborate description and figured the brain of 

 Otaria jubata, and Mivart has figured and described some of the convolutions of Otaria 

 (Eumetopias) gillespii. The only observation on the brain of the Walrus to which I can 

 find a reference is by Sir Richard Owen, who states, in the course of an account of the 

 dissection of a female Walrus which died in the Zoological Gardens, " the brain weighed 

 1 lb. 9 oz. avoirdupois ; its convolutions and structure were described," but no further 

 statement is made regarding them. 



Numerous anatomists have, however, described in more or less detail the brains of 

 various Carnivora, more especially the Dogs, Cats, and Bears ; and through their researches 

 the plan of construction of the Carnivorous brain and the arrangement of the convolutions 

 have been worked out with considerable detail. The convolutions and sulci have also 

 received names, though not unfrecmently confusion has arisen both through different 

 parts being similarly named and through the same part being differently named by 

 investigators. The affinity between the Pinnipedia and the proper Carnivora is shown 

 by certain resemblances in brain-structure and arrangement, and as in the study of the 

 brain in the Seals and Walrus the anatomist finds it necessary to refer frecpiently to 

 the brain of the Dog, Cat, &c, it may be useful to give in this place references to the 

 principal sources of information on the brain of this order of mammals. 



(zool. chall. exp. — paet Lxvin. — 1888.) Yyy 12 



