EASTMAN : sharks' TEETH AND CETACEAN BONES. 83 



shall do well at this time to devote a larger share of attention to the 

 deep-sea Mammalian remains. 



Cetacea. 



Cetacean remains were dredged in greater abundance, and from more 

 numerous localities, during the "Alljatross " Expedition of 1904-1905 

 than on the previous cruise of this vessel in the tropical Pacific. The 

 Expedition of 1904-1905 was also successful in bringing up Cetacean 

 teeth for the first time from great depths, two such l)eing contained in 

 the collection. On the other hand, no indications of Mystacocete whales 

 were observed, and it is regarded as quite remarkable that neither tlie 

 *' Albatross " nor " Challenger " Expeditions encountered any traces of 

 the great sperm whale (Physeter macrocephalu^), notwithstanding that 

 numerous hauls were made within the usual habitat of this animal. 

 Remains* of the closely allied pygmy sperm whale, however, occurred at 

 several localities. Ear-bones of Dolphins constitute tlie greater part of 

 the material, as might be expected, although apparently not more than 

 one or two species are represented. Next in order of abundance are the 

 Cxar-bones of Hyperooilon, whose habits are gregarious. Several speci- 

 mens belonging to this genus are scarcely discolored, and present an 

 exceedingly fresh appearance. 



The state of preservation of tlie remains as a whole differs in no 

 respect from that wliich has been previously observed, and is described 

 by Professor Sir William Turner in following language : ^ 



The preservation of the ear-bones and of the fragments of tlie beaks of zipliioid 

 whales is accounted for by tlie extreme density of these portions of the skeleton. 

 Some of the bones were in a much better state of preservation than others. In 

 some the manganese coating was extremely thin, and but little liad entered into the 

 Haversian canals and lacunae, so that a fractured surface was greyish-white (Mr. 

 Murray's PI. X. Figs la, \h, 2n, 4a). Otliers again were not only thickly encrusted 

 with the mineral, but the Haversian canals and lacunae were infiltrated with it, so 

 that a fractured surface was dark brown or black, and the bones were e.xtremely 

 brittle. The chemical composition of these bones was thus entirely altered, and 

 this was more especially the case with the fragments of the flat bones, and others 

 of a more porous texture which formed the nuclei of so many of the manganese and 

 iron nodules. ... It Is to be noted that the bones obtained did not present any evi- 

 dence of having been rolled or rubbed They had evidently rested quietly in the 

 spots where they had been deposited, and in many cases the tympanic and petrous 

 bones were still attached to each other, although they could be separated by the 

 exercise of but little force. 



I Turner, W., Report on Bones of the Cetacea. Sci. Results Chall. Exped. Zool. 

 vol. 1, 1880, p. 41. 



