220 PROCEEDINGS OF THE ACADEMY OF [April, 



Eulalia quadrioculata sp. nov. Plate X, figs. 4-6. 



This description is based upon a single much contracted entire 

 specimen (type) and a fragment of the anterior end of another in every- 

 way similar. 



The type is 27 mm. long, the protruded proboscis 2 mm. additional, 

 the width without parapodia 2 mm., with parapodia 3 mm., the diameter 

 of the distal end of the proboscis 2.5 mm., and the number of segments 

 106. 



The evidently much contracted prostomium (fig. 4) is about two- 

 thirds as long as wide, scarcely emarginated in the median line pos- 

 teriorly, rather tumid in the posterior lateral part and then slightly 

 concave to a small truncate median anterior lobe. The usual pair of 

 eyes are transversely elliptical, situated on the dorsal surface of the 

 prostomium about three times their diameter apart, nearly twice their 

 diameter from the lateral margins of the head and not more than 

 their diameter from the posterior margin. They have distinct lenses. 

 In nearly the same transverse line or very slightly in advance and half 

 way between the dorsal eyes and the margin, or just within the nuchal 

 organs, is a second pair of eye-like spots of black pigment, but lenseless 

 and smaller and more irregular than the dorsal eyes. 



The four frontal tentacles are subequal, about as long as the head, 

 and rather thick, with acute tips. The ventral pair project somewhat 

 downwards, the dorsal directly outwards. From the middle of the 

 small lobe lying between the frontal tentacles a shallow longitudinal 

 groove passes to the median tentacle, which arises from a point just 

 anterior to the eyes. It equals the frontal tentacles in length, but is 

 slightly more slender in its distal part. The four tentacular cirri arise 

 in the positions usual in the genus from somites I, II and III, and are 

 short and subequal, being about twice the length of the prostomium. 



The segments are all well differentiated and dorsally are strongly 

 arched; anteriorly they are strictly simple smooth rings, but in the 

 posterior third become biannulate. Ventrally the body is marked by 

 a neural groove and lateral ridges bearing glandular areas ventral to 

 the parapodia. On this surface the biannulation extends nearly to the 

 anterior end. The anterior segments are contracted and extremely 

 short, farther back they become relatively longer, and toward the 

 posterior end the body is distinctly flattened. The pygidium, which 

 is provided with a thickened welt-like rim surrounding the anus, 

 bears on the ventral side a pair of prominent acuminate cirri resembling 

 the ventral cirri in size. 



Parapodia are located at the level of the ventral surface. That on 



