POLYCH^TA— BENHAM. 21 



The median prostomial tentacles in the present specimens have 16amiiili; the 

 laterals 12 ; the dorsal peristomial cirri present 17-18 ; the ventrals 15 (Ehlers found in 

 a specimen from the Chatham Islands as many as 21-23 respectively). 



The dorsal cirri have a spindle-shape outline, which is characteristic for the 

 species ; the cirri of the anterior six to eight segments are longer than the rest ; their 

 length is greater than the breadth of the body here ; the sixth being the longest ; it 

 has 20 annuli. 



The remainder of the dorsal cirri are fairly uniform in length, but not absolutely 

 so ; though this seems to me due to inequality in contraction. 



The length of these cirri over tlie greater part of the body is rather less than the 

 breadth of the body ; I find 12-13 annuli in most of them. Ehlers gives 8-11, usually 

 the latter, and in specimens from the Chatham Islands as many as 21. Fauvel gives 

 10-15 for Red Sea specimens. 



I find (fig. 1) that each parapod is supported by 3 or even 4 acicula, which lie 

 close to one another above the bundle of chaeta\ The end of each aciculum is dilated 

 just below the blunt tip, which is obliquely truncated and projects from the surface, 

 (fig. 2). In some individuals, however, there is no dilatation, and the apex is 

 symmetrically pointed. 



The pharynx commences in the 4th chaetigerous segment, as is seen in a specimen 

 mounted entire in glycerine ; it extends back to the tenth segment, where it enters the 

 " stomach" (or " ventriculus " ) which occupies segments 11-18; the intestine at first 

 passes forwards from this point, and then bends backwards. It is from the former 

 region that the pair of long cylindrical caeca are given off, one of which reaches forwards 

 into the 14th, the other only as far as the 15th segment. 



Epitokous Phases. 



A male and a female occur amongst the material gathered at Boat Harboiu: at 

 3i fathoms. 



They measure 12 nun. in length, with a width of 1 mm., and contain about 

 32 segments. The eyes are large and red. They agree generally with the account 

 and figmres given by Ehlers. 



I note, however, that four eyes are present in both sexes, one pair on the dorsal, 

 the other pair on the ventral surface. Ehlers figure shows the male to be bUnd. 



The prostomial tentacles of the male are longer than in the female, but are not 

 moniliform in either sex. 



The male is entire, and possesses two long moniliform anal cirri, longer than the 

 dorsal cirri of that region. In the male the long modified chseta conunence in the 

 third chtct'gerous ssgment. in t'le female in the sej'ond. ' ■ • 



Ehlers notes that the spawning time occurs in December and January. These 

 were gathered in the former month. 



