246 



WHALES 



b 



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Figure i2y. Classification of a number ofCetacea and other mammals according to (a) total 

 weight of brain; {b) ratio of brain to body weight; (c) ratio of brain to brain-stem weight 



( Wirz's system) . 



brain of Bottlenose Whales (6-6 lb.), Pilot Whales (4-5113.), Belugas 

 (4-2 lb.), Bottlenose Dolphins (41b.), Narwhals (3-1 lb.) are bigger than 

 that of man, while that of the Common Dolphin (about 2-2 lb.) and the 

 porpoise (about i -2 lb.) is smaller. 



Clearly mere weight of brain can tell us little about an animal's mental 

 capacities, for otherwise an elephant would be more than three times as 

 intelligent as man, and a Rorqual would have an unheard-of I. Q. If we 

 look instead at the ratio of brain to body weight, we find that the brain of 



