220 " ENDEAVOUR " SCIENTIFIC RESULTS. 



The peristomium and nuchal segment together are broader 

 than their length, which is about equal to 2^ chsetigerous 

 segments. 



The peristomium is slightly excavated on the dorsal sur- 

 face ; the lower lip is not so deeply notched as it is in E. 

 pycnobranchiata, and its upper margin is not visible from 

 above (PI. xli., fig. 67). 



The nuchal cirri present 8 annulations ; they fail to reach 

 the anterior margin of the peristomium by a space about 

 equal to the length of the nuchal segment. 



The dorsal cirri are also distinctly moniliform, and re- 

 latively stout. Anteriorly, there are four dilations, the 

 terminal being elongated, and under a dissecting lens may 

 appear to be constricted, but in a preparation this is seen 

 to be only a, " bend," not really a constriction. 



As in the tentacles, the furrows are pigmented. 



After about the 6th segment, and throughout the rest 

 of the body, only three dilations exist, but there appears 

 to be some variation in this, for in some individuals, the feet 

 of which were mounted, four appear (PI. xli., fig. 70). The 

 anterior dorsal cirri are particularly stout. 



The ventral cirri of about the first half dozen feet are 

 short, rounded sub-spherical lobes ; further back this lobe 

 bears a short stout bluntly rounded conical appendage, 

 while over the greater part of the body the latter elongates 

 and the basal lobe decreases. 



The anal cirri, also moniliform, have a length equal to 

 the last 10-12 segments. 



The gills commence on the 6th chsetigerous segment (in 

 this and all the anterior ends available), and are continuoxis 

 to the posterior end of the animal. In this individual the 

 first gill has 4 filaments the maximum is 10 and this 

 number occurs over the segments 8-9, after which there is 

 a gradual and fairly regular decrease, with here and there 

 an occasional addition of one filament. Thus on segments 

 40-60 there are 4 filaments ; on 61 only 3 ; on 90 the number 

 is again 4, but on segment 100 the number once more scales to 

 3, and then to 2, and to 1 at the last few segments. 



This cannot be regarded as a " posterior enlargement ' 

 of gills, such as occurs in one or two other species (see below). 



As to the relation between the size of the gill, even at its 

 maximum stage of development, one cannot regard them as 



