CHARACTERISTIC DEEP-SEA TYPES. CRUSTACEA. 



51 



uncommon West Indian type from the globigerina ooze : it be- 

 longs to the group having no peduncle. 



As has been noticed by Hoek, the presence of Scalpellum and 

 Verruca in the great depths of the ocean coincides in a strik- 

 ing manner with the palseontological history of these genera. 

 They are found in the secondary deposits, yet the genus Pol- 

 licipes, another of the pedunculated cirripeds, dating back to the 

 oolite, is only a littoral genus in our seas. 



The ostracods are minute crustaceans, the dead tests of which 

 occur in nearly all the bottom deposits. They are very abundant 

 fossils, but the deep-sea dredgings have not as yet revealed 

 any type of 



im- 



portance. Many of 

 the ostracods (Fig. 

 259) are pelagic ; 

 only a compara- 

 tively small num- 

 ber live at any 

 considerable depth 

 moderate depths. 



Fig. 259. Cypris. Greatly magnified. 



they are denizens of shallow water or of 



