THE AMERICAN MUSEUM JOURNAL 



some blue markings below. The male was a very yotmg one, 

 onlv 1 6 feet long, but closely resembled the female, wliich evi- 

 dently was its mother. The fact that the skeleton was incom- 

 pletely ossified indicated the immature condition of the animal. 

 The hard parts of both whales were obtained and cached for 

 future attention. 



These individuals belong to the group of whalebone whales 

 and to the genus Balccnopicra. Probably they are specimens of 

 B. imiscuhts, which is the most common whale of temperate cli- 

 mates. Whalers know this species as the "Firmer" or '"Fin- 

 back," and do not prize it, on account of the small amount of 

 blubber and the small size of the whalebone which it carries. In 

 the large specimen here mentioned the longest plate of whale- 

 bone was only 2 feet long, while in the Right Whale it is often 1 2 

 feet in length. 



Whales, probably, are descendants of terrestrial mammals 

 which have assumed an aquatic existence, a change of life which 

 has been accompanied by remarkable modifications in the struc- 

 ttue of the animals. Some organs have become highly special- 

 ized, while others have completely degenerated. Teeth, which 

 are a characteristic feature of land mammals, are entirely lacking 

 in the adult Fin-back, their place being taken in part by the 

 whalebone. The forelimbs have ceased to be appendages of 

 locomotion and have become mainly balancing organs. They 

 resemble the pectoral fins of fish, although they still retain the 

 structural plan of the mammalian forelimb. The hindlimbs and 

 pelvis have disappeared entirely externally, and internally are 

 represented only by two nodules of bone. The whale, in fact, is 

 one of the best examples known illustrating the influence of 

 environment in the modification of structure. 



RECEXT PUBLICATIONS. 



The following articles of Vol. XVI (1902) of the Museum 

 "Bulletin" have been issued since April 23, completing the 

 volume : 



10 



