ANNELIDS OF FAMILY NEREIDAE HARTMAN 



473 



Description. — Prostomium (fig. 49, a) narrowest anteriorly, widest 

 in posterior third; provided with four black or brownish eyes dis- 

 posed on widened posterior portion of prostomium. 



Antennae two-thirds as long as prostomium, proximally separated 

 by distance equal to diameter of their bases, diverging distally, and 

 extending to a point between distal end of palpode and its style. 



Palpi compressed-cylindrical, attached to prostomium so as to 

 leave a free area almost equal to width of prostomium between 

 ectal bases of antennae; palpode thickened in basal third, tapering 

 distally and terminating in a spherical palpostyle (fig. 49, a). 



Figure 49. — Nereis (Nereis) eakini, new species : a. Anterior end in dorsal view, X 13 ; 

 h, tenth parapodium in anterior view, X 40; c, posterior parapodiiim in posterior 

 view, X 40 ; d, faleigerous heterogompb neuroseta, X 333 ; e, articulation of pointed 

 heterogomph neuroseta, X 333 ; f, faleigerous homogompli notoseta, X 333. 



Peristomium (fig. 49, a) dorsally seven-fifths as long as, and some- 

 what narrower than, or equally as wide as, segment 2; produced 

 ventrally into a smooth lower lip, which extends slightly into second 

 segment at the middle. 



Paragnaths very numerous, dark or medium brown; area I with 

 two to four small teeth in tandem; II with many round low cones, 

 forming a longitudinal crescent between jaws; III with four to six 

 teeth in a small transverse mass; IV with a large diagonal area 

 of many round low teeth ; V-VIII with a continuous band of many 

 distinct, low, round cones of unequal sizes, completely covering basal 

 half of oral ring, the largest cones on area VI, the smallest on the 

 side of the oral opening. 



Jaws deep, horny brown, with only three or four shallow teeth, 

 which do not project from concave edge of jaw. 



