172 THE ANNELIDA POLYCHAETA. 



often obscure. The edge below the lower tooth extends out into an obtuse angle, 

 above which it is finely, shortly setose. (Plate 21, fig. 2). The simple setae are 

 very fine and numerous, twenty or more in each group. 



Locality. Gilbert Islands, off Apaiang. Surface. Surface temp. 84° F. 

 3 January, 1900. One specimen taken at night by electric light. 



A strongly marked species characterized by the conspicuously enlarged 

 and flattened palpi at base extending back between eyes, in the presence of setae 

 on the second somite, and in the comparatively large number of somites in the 

 anterior division of the body. 



AUTOLYTUS TORQTJENS, Sp. nOV.^ 



Plate 19, fig. 5-7. 

 Pelagic Female (Sacconereis) . 



The general color is an opaque yellow, this being due to the dense mass of 

 eggs filling the body, the integument itself being transparent or translucent; 

 the tentacles and cirri are colorless, or nearly so, and translucent. 



The body in the type is nearly 15 mm. long, the precise length not being 

 ascertainable because of the strongly coiled state. The body is slender, widest 

 near beginning of the second third of length from where it narrows cephalad 

 and very gradually caudad, the posterior region becoming very slender. The 

 total number of somites is nearly one hundred. Of the setigerous somites the 

 first six belong to the anterior division of the body, in which only the short com- 

 posite setae are present. 



The prostomium is transversely oblong, with the anterior margin widely 

 angularly indented or evenly incurved at the middle between the paired ten- 

 tacles. Each paired tentacle situated on the anterior margin toward the ectal 

 end in front of the eye; short, tapered, very distinctly annulated. The median 

 tentacle is attached on the dorsal surface between the eyes and is somewhat 

 larger than the paired tentacles. The anterior eyes are much larger than the 

 posterior; each is situated on the anteroectal portion of the prostomium which 

 bulges out conspicuously, and its lens is directed nearly ectad. The posterior 

 eyes are much smaller; each is situated obhquely mesocaudad of the correspond- 

 ing anterior eye. 



The first somite is considerably raised above the level of the prostomium. 



 torquere, to twist or curl. 



