^^^^J Essenherg: New Species of Polynoidae 51 



widely overlapping elytra. The dorsal and ventral surfaces are eon- 

 vex and the thirty-seven segments are well marked. The length of 

 the body is 35 mm., and the width, including the setae is 14 mm. in 

 the widest part of the body between segments 15 and 16. From these 

 segments the body alternates very gradually towards both ends, more 

 strongly towards the posterior end. The width of the body, excluding 

 the setae and parapodia, is about one-third of the entire width, the 

 length of each parapodium including setae being equal to the width 

 of the body, or the parapodia and setae make up two-thirds of the 

 entire width of the body. 



The prostomium (pi. 2, fig. 12) is deep and broad; the length of 

 the prostomium being only about two-thirds of the width. It is 

 deeply fissured with acuminated anterior peaks. There are two pairs 

 of comparatively small and equal-sized eyes. The anterior eyes are 

 anterior to the widest part of the prostomium, while the posterior 

 pair are near the center of the prostomium, about two-thirds of the 

 distance from the anterior margin. The style of the median tentacle 

 is missing. The strongly developed cirratophore is deeply inserted 

 between the prostomial lobes. The lateral tentacles arise from 

 prominent cirratophores. The styles are very short, being only 

 slightly longer than the cirratophores. The length of the lateral 

 tentacles, including the styles and cirratophores is about one-third 

 of that of the prostomium. The palpi are stout and uniform in width 

 near the base attenuating very gradually toward the distal ends. 

 They are round and perfectly smooth without any papillae or cilia, 

 slightly longer than the peristomial cirri. 



The parapodia (pi. 2, fig. 14) are long, their length being equal 

 to the width of the body, biramous, each ramus terminating in a nar- 

 row, finger-like projection, and is supported by a strong dark brown 

 aciculum. The cirratophores of the dorsal cirri are very long, their 

 length being about one-third of that of the style. The latter decreases 

 very gradually in diameter toward the distal end, terminating in a 

 fine filamentous tip. The neurocirrus occurs on all segments and 

 consists of a strong cirratophore and a fusiform style. 



The setae are numerous, from 70-100 on each parapodium. They 

 are distinctly of three kinds, with gradations between, in size, as 

 well as in structure. They are longest towards the center, decreasing 

 in length ventrally and dorsally. The neurosetae (pi. 2, figs. 16 and 

 17) are long and slender, the longest neurosetae being equal in length 

 to that of the parapodium and are twice the length of the stout noto- 



