SHARKS' TEETH AND CETACEAN BONES. 



181 



bnriiil. It sliould be stated tliat in the great majority of the "Challenger" 

 teeth, all that remains is the hard dentine or enamel, the root and whole 

 of the vasodentine having been dissolved away. 



During the years 1887-1889 extensive deep-sea dredging operations were 

 carried on in the Indian Ocean by English and French hydrographers, the 

 scientific results of which were discussed by Dr. Murray in two communi- 

 cations published in the Scottish Geographical Magazine.' Among the 

 more striking features of these investigations was the discovery by Captain 

 Pelham Aid rich in H. M. S. "Egeria" of semi-fossil teeth of sharks and ear- 

 bones of whales, all more or less encrusted with peroxide of manganese, as 

 had already been observed by the "Challenger" in similar areas of the 

 Atlantic and Pacific. The author again calls attention to the fact that two 

 of these species, Carchwodon vicgdludon and Oxyrhina liastUis, are charac- 

 teristic of the middle Tertiaries, and, so far cas known, are not now existing. 



The most recent and only othe'* source from which this cliiss of organic 

 remains has been derived is the "Albatross" Expedition of 1899-1900, 

 which forms the basis of the present report. During this cruise vertebrate 

 material was dredged from five stations in the Pacific, whose positions, depths, 

 and Ijottom characters are given in the following table:'" 



Li.sT OF " Alb.\tros.s" Stations yielding Sharks' Tektu and Cetacean Bones. 



' On .some Recent Deei>Sea Observations in the Indian Ocean ; Scottish Geog. Mag., Vol. HI. 

 (1887), pp. r).'3:J-567. On Marine Deposits in tlie Indian, Southern, and Antarctic Oceans; Ibid., Vol. 

 V. (1889), pp. 40.5-13G. Cf. also Geol. Mag. [3], Vol. VI. (1889), pp. 5Il-ol7, Figs. 1-1. 



- Agassiz. A , Preliminary Report and List of Stations, with Remarks on the Deep-Sea Deposits 

 by Sir John Murray; Mem. Miis. Comp. Zool., Vol. X.KVI. (1902), pp. 1-114. Cf. also 7'ownaeml, 

 C. H., Dredging and other Records of tlie United States Fish Commission Steamer " Albatross," 

 U. S. Fish Com. Itept. for 1900 (1901), pp. 387-502. 



