38 



THE FAUNA OF THE DEEP SEA 



posed of carbonate of lime. The remaining five per 

 cent, is composed of sulphate and phosphate of lime, 

 carbonate of ammonia, the oxides of iron and 

 manganese, and argillaceous matters. The oxides of 

 iron and manganese are probably of meteoric origin ; 

 the argillaceous matter may be due to the trituration 



Fig. 3. — Globigerina ooze. (After Agassiz.) 



of lumps of pumice stone and to the deposits caused 

 by dust storms. 



Globigerina ooze may be found on the floor of 

 the ocean at depths ranging from 500 to 2,800 

 fathoms of water in equatorial and temperate lati- 

 tudes. The reason that it is not found in Arctic 

 seas may be that the cold surface waters of these 

 regions do net bear such an abundant fauna of Fora- 



