LEPTONEREIS GLAUCA CLPDE. AND GENUS LEPTONEREIS KINBERG. 247 



think that the papillae must have escaped observation in the other 

 cases. 



Their presence, of course, rather upsets the characterisation of the 

 genus, which has hitherto been based solely on the total absence of 

 paragnaths or papillae ! 



A remarkable feature was exhibited by a number of specimens col- 

 lected on 20th March. These bore on the proboscis four patches of a 

 jet-black colour, radiating outwards from the bases of the jaws, in the 

 everted proboscis, towards the areas where groups II and IV of the 

 paragnaths would, if present, occur. These black marks appeared to 

 consist of a deposit of opaque pigment beneath the cuticle. Fig. 1 is 

 taken from a typical specimen, and shows the two dorsal patches. Of 

 twelve specimens collected on this date, eight showed these patches 

 strongly developed, while the remainder exhibited no trace of them. 



The black marks were still present when the specimens were re-examined 

 after lying for some weeks in alcohol and formol, but by October, 1913, 

 all traces of them had disappeared. Fortunately, however, one specimen 

 had been mounted in balsam at the earlier date, and in this (the specimen 

 figured) the black is perfectly preserved. Further investigation of its 

 nature is desirable. The only other specimens which I examined in a 

 fresh state had the proboscis inverted ; the rest of the material had been 

 lying in spirit for some months.* 



The parapodia of Leptonereis have been described in detail by St, 

 Joseph, but I have thought it useful to figure these again, as they are 

 the chief means of identification. (St. Joseph's figures are rather 

 grotesque. f) They do not differ from the typical nereis-form of parapod 

 except in that their noto- and neuropodia are more deeply and widely 

 separated than usual. They are approximately similar from end to end 

 of the body. The noto-cirri are rather short, usually slightly over- 

 reaching the ligule ; a slight increase in relative length of the cirri 

 usually takes place in the posterior half of the body. 



The setae, which have been figured by Claparede, St. Joseph, and 

 Mcintosh, have the typical nereid arrangement, thus : — 



Notopodial bundle, homogomph spinigers. 



TT T ,1 Ti f homogomph spinigers (above). 



Upper neuropodial bundle! . ^ " i r , • \ , 



[heterogomph talcigers (below). 



, T , 1 n fheterogomph spinigers (above). 



Lower neuropodial bundle-^ . , <• i • ,\ , 



[heterogomph talcigers (below). 



* The everted probosces of more than a dozen of the living specimens received in 

 December, 1913, showed on examination no trace of these black patches, 

 t Claparede's single figure of a parapod is also unnatural. 



