G98 



THE VOYAGE OF H.M.S. CHALLENGER. 



IV. "TRITON" EXPEDITION. 



(1.) Littoral Zone. 



Species found in depths which extend from the Shore to 150 fathoms. 



(2.) Continental Zone. 

 ■■ Species found in depths between 150 fathoms and 500 fathoms. 



(3.) Abyssal Zone. 

 Species found in depths greater than 500 fathoms. 



