vii:\v> <»i N.virui: ( on ij;asti;i). 17 



has ludirisheil tlic body, a vnitriclc sends it to bo vivilicd 

 by tho oxy;;cn in tin- water, whieb UKjistens tlic ^ill liia- 

 nionts ; from the ^^ills it eonnncnccs in a dorsal vessel a 

 lonj^; course tbroui^b the body, before a;^ain returning to the 

 heart. The bbuxl in the ectaeeans is warm, in tlie lishes it 

 is called cold. Tin dillercnccs which do exist have been 

 generally exair.m'J'ated. however, and I only mention them 

 because so much importance is j)0|>ularly attached to them. 

 The important orj^ans we have been last con.siderinii — 

 tho heart antl tho lungs — are inclosed in a special cavity of 

 tlu' chest, and separated by a partition or diaphragm from 

 the other viscera, alike in the whales and other mammals. 

 Heart and air bladder or lungs arc far apart, and separated 

 by — not iVom — other viscera in the fishes, and there is notli- 

 ing like a diaphragm to partition off a special cavity for 

 them. 



We will next consider the brains of a whale and of a 

 fish. They are entirely dissimilar. The brain of a whale 

 is essentially the same as that of a man. and extremely 

 dift'erent from that of a iish. 1 exhibit the brains of a 

 porpoise and a man. and you can contrast them with the 

 enlarged figure of the brain of a salmon. 



These illustrations will give an adequate idea — at least so 

 far as we are at present concerned — of tho structure of all 

 i)rains in the two widely separated classes comprising man 

 and the whales on one hand, and the fishes on the other. 

 Not only are the first two superficially essentially the same, 

 but all the ])arts are readily comparable, and tho closer you 

 examine the more you will be struck by theii" similarity 

 rather than their dillerence. when you taki' into account 

 the diffenMices in the form of the body. lint compare with 

 the brain of that, or any other cetacean, the brain of a Iish, 

 and the differences are very marked. 



In the mammal brain the optic lobes arc represented by 

 sntall tubercles or lobe, while in the Iish they are of |)re- 

 ponderating development. The olfactory lobes and nerves 

 are entirely concealed by the cerebrum and even almost 

 wanting in the cataceans, l)ut they are very large, and ad- 



