106 ANNELIDA. 



antennae; two eyes. (Shield-plates concealed in 

 the British species by a sort of felt formed of the 

 dorsal bristles.) 



A. aculeata. Fig. 180 ; | n. s. 

 hystrix. 

 borealis. 



Animals of doubtful position, probably belonging to 



the Annelida. 



Tomopteris (Eschscholtz) =Johnstonella (Gosse). 

 Body long, excessively thin, transparent, cut into 

 many lobes on each side ; head furnished with 

 two greatly lengthened antennae directed back- 

 wards, and with two pointed processes in front 

 directed sideways ; eyes two ; proboscis evertile. 



T. scolopendra. Fig. 181 ; mag. -f-. 



Sagitta (Quoy and Gaimard). Body long, slender, 

 gelatinous, fish-like, with two pairs of lateral fins, 

 and an expanded triangular fin-like tail; head 

 large, with two eyes, and many pairs of expanding 

 hooked jaws. 



S. bipunctata (?). Fig. 182; mag. f. 



