PARAONIDAE 



151 



when seen from above, is triangular in outline and ends in a sharp point, which I take 



to represent the terminal tentacle mentioned by Mesnil and Caullery. There is only a 



single achaetous segment, the buccal segment, behind the prostomium (Fig. 58, a). 



I can find no dorsal cirrus on the ist chaetiger and the upper and lower bristle bundles 



issue directly from the body wall without any parapodial lobes. In the 2nd and following 



chaetigers there is a small papilliform dorsal cirrus. Mesnil and Caullery state that the 



first three chaetigers are clearly smaller than those that follow. My specimens do not 



show this. 



•lTnm.1 



6 mm. 



•2min 



lo 



O-L 



0^ 



-T'lmxrL 



-LQ 



a 



Fig. 58. Paraoiiis gracilis. "■ 



Anterior end. (The feet are not shown behind the 5th chaetiger.) b. Capillary bristle. 

 c. Hook. d. Dorsal view of foot and genital papilla. 



The gills begin on the 6th-7th chaetiger and continue to the i8th-20th chaetiger. 

 They are simple strap-like structures, arching over the back. The gill-bearing region 

 of the body is flattened dorsally and rounded ventrally and the limits of the segments 

 are clearly marked. Behind this region the body is cylindrical and the limits of the 

 segments are almost impossible to distinguish. From the distance apart of the chaetal 

 bundles it can be seen that the segments are about twice as long as in the anterior region. 

 The posterior region of the body looks much more like a fragment of some microdrilid 

 Oligochaete, such as Nais, than part of a Polychaete. 



