4 PEOCEEDIlSrGS OF THE NATIONAL MUSEUM vol. 69 



of 4 mm, at the prostomiiim and more sharply to 2 mm. on the anal 

 somite. There are 28 somites. 



The caruncle (fig. 1) is divided longitudinally into a median and 

 two lateral sections, the three being in contact anteriorly and poste- 

 riorly but widely separated throughout the greater part of their 

 length. The median portion has a narrow central axis, with about 

 30 vertical lobes along either margin. Each lateral portion is a 

 vertical lamella, bent so as to form about 20 close loops. Posteriorly 

 the three sections unite to form a pointed end, just over the anterior 

 margin of somite 6, the posterior point of attachment of the caruncle 

 being on somite 4. Anteriorly the lateral portions merge into the 

 margins of the prostomium, while the median portion, which through- 

 out is higher than the others, is continued over the prostomium as 

 a crest, ending in a rounded smooth lobe at the level of the anterior 

 pair of eyes. 



The unpaired tentacle is attached near the anterior end of this 

 median division of the caruncle. It is slender and inconspicuous 

 and extends to the posterior margin of setigerous somite 2. There 

 are two pairs of prominent black eyes, the anterior ones slightly the 

 larger, and situated in front of, and anterior to, the end of the 

 caruncle. The posterior eyes are about as far from the anterior 

 ones as these are from one another. The dorsal paired tentacles are 

 similar in form and size to the median unpaired, and lie one on 

 either side just in front of the anterior eye. From the base of each 

 paired dorsal tentacle a ridge runs forward to merge with the 

 anterior border of the prostomium. These diverge a little from 

 one another so that the groove between them is widest at the anterior 

 end. They merge into the surface of the upper lip which has no 

 groove in its anterior margin. In the channels between these two 

 ridges, and in a similar depression on either side is an accumula- 

 tion of dark pigment, colored much like the eyes. The ventral 

 paired tentacles are similar in form to the dorsal and lie between 

 the anterior margin of the first setigerous somite and the pigmented 

 channel. Aside from the above-mentioned pigment, the only trace 

 of color is a narrow band on the anterior face of each notopodium 

 of anterior somites. These are darkest in the anterior somites, 

 become less intense farther back, and eventually disappear entirely 

 at about the middle of the body. 



On the ventral surface is a very shallow and broad median groove. 

 The anterior margin of the fourth somite bounds the mouth pos- 

 teriorly; anteriorly and laterally it is bounded by the narrow hoof- 

 shaped upper lip, which is formed by setigerous somites 1 and 2, 

 while its lateral margin on either side is formed by setigerous 

 somite 3. 



