182 EXPEDITION OF THE "ALBATROSS," 1899-190(1. 



Comparison of Vertebrate Kemains Dredged by the " Albatross " 

 and "Challenger" Expeditions. 



As the line run by the "Albatross" from San Francisco to Tahiti con- 

 verges toward that run by the " Challenger " from the Hawaiian Islands to 

 Tahiti, where the two cross, it is interesting to compare the results of deep- 

 sea dredging accomplished on these voyages. On the run from San Francisco 

 to Tahiti the " Albatross " made eleven deep-sea dredgings, four of which 

 brought np sharks' teeth, as shown in the above table. On the course west- 

 ward to the Fiji Islands, and thence northwesterly to Japan, three such deep- 

 sea hauls were made, one of which (at Station 183, between Cook Islands 

 and Tonga) yielded vertebrate remains. 



Following the track of the "Challenger" from Yokohama, Japan, due 

 east to the meridian passing through the Hawaiian Islands, and thence south 

 to Tahiti, we find that eight stations are distributed along this route which 

 yielded the same class of organic remains ; but on the run from Tahiti to 

 Valparaiso material of like nature was dredged at, but one locality to the 

 eastward of the Paumotu group, namely, at Station 293. The comparative 

 paucity of vertebrate remains on the ocean-floor for a distance of 4,000 miles 

 between parallels 30° and 40° of south latitude, as contrasted with their wide 

 distribution and abundance elsewhere in the Pacific, is probably to be 

 accounted for by the fact that this belt lies outside the south equatorial 

 current, and that it has not been frequented by large sharks and Cetaceans 

 since Tertiary times, or. even longer. During the Tertiary, however, Car- 

 charodons of enormous size ranged along the western coast of America from 

 California to Patagonia, as is shown by their fossil remains. 



Numerous Cetacean bones were dredged by the "Challenger" from the 

 red clay in the vicinity of Tahiti (Stations 276-285), and it is regarded by 

 Sir John Murray as rather surprising that none were in the material from 

 the "Albatross" Station 173, which lies within the same area. 1 However, it 

 is well known that the percentage of Mammalian remains brought up in the 

 great majority of the " Challenger's " deep-sea dredgings was very small, 

 and that, as Dr. Murray has himself stated, 2 "in all the terrigenous deposits 



1 Mem. Mas. Comp. Zool, Vol. XXVI. (1902), p. 110. 



2 Report on the Deep-Sea Deposits; Sclent. Results " Chall." Exp. (1891), p. 270. 



