DEEP-SEA FORMATIONS. 145 



others, dredged a few manatee ribs in the Straits of Florida. 

 Neither the Fish Commission nor the " Blake " has been equally 

 successful. The " Challenger," however, dredged thousands 

 of sharks' teeth and cetacean bones in 2,300 to 2,800 fathoms. 

 They were f>rincipally found in restricted areas, far removed 

 from land, in the abyssal red-clay regions, where the rate of ac- 

 cumulation is very slow, and where such bones are not likely to 

 be buried by detritus coming from the shores, or by the more 

 rapid deposition going on along continental shelves. These 

 deposits may be analogous to the bone beds of the corniferous, 

 or 23erhaps to the phosphate beds of South Carolina, or the 

 Cambridge coprolite beds. On the east coast of the United 

 States, and in the Gulf of Mexico and the Caribbean, sharks' 

 teeth have been dredged, but rarely. Either the sharks of 

 former times were much more numerous, or, as has been sug- 

 gested by Professor Verrill, their remains, as well as those of 

 fishes ^ and other vertebrates, were not immediately devoured 

 by other inhabitants of the deep sea. One would also exj^ect 

 that the bones of porpoises would be common in localities 

 where they are often seen sporting by hundreds, as along the 

 Windward Islands. Yet none were dredged by the " Blake." 



An examination of the fossils from many of the raised sea- 

 beaches reveals types Avhich the late explorations have shown 

 to be deep-sea forms. Seguenza was the first, in studying the 

 pliocene deposits of southern Italy, to show that some of them 

 were deposited in deep water. He suggested that the forami- 

 niferous, bryozoan, coral, and radiolarian beds were deposits 

 which must have been laid down at considerable depths ; he was 

 led to this conclusion by a comparison of their fossils with the 

 animals of the present day found at great depths. Before the 

 recent deep-sea investigations, geologists were misled by the 

 strange forms contained in many of the foraminiferal deep-sea 

 deposits of the tertiary period, and looked upon these deposits 

 as much older than they were in reality. 



Fuchs has also compared other beds of the tertiary, on account 

 of their characteristic fossils, with certain deep-sea dejaosits. The 



1 Otoliths of fishes occur not uufrequently in the fine niiuls of the Gulf of 

 Mexico. 



