274 ZOOLOGY SECT, v 



Sub-Class II. Schizonemertea. 



Nemertinea in which there is a deep lateral longitudinal groove 

 on each side of the head and in which the proboscis is devoid of 

 stylets. 



Sub-Class III. Hoplonemertea. 



Nemertinea in which there are no deep lateral grooves on the 

 head and in which (except in Malacobdella} the proboscis is armed 

 with a stylet. 



The Nemerteans are almost exclusively marine, only a small 

 number of species living in fresh water or in damp localities on 

 land. None appear to be true parasites ; but a few are com- 

 mensals, living for the most part in the pharynx or atrial cavity of 

 Ascidians or Sea-Squirts. All are carnivorous, and either capture 

 living prey in the shape of small-bodied invertebrates uf various- 

 kinds, or feed on dead fragments. 



