264 LEPTONEREIS VAILLANTI. 



(or soft papillae ?) ; form of foot altering by degrees, the superior branchiae (lamellae) 

 becoming large posteriorly— elongate and compressed; the dorsal cirri terminal; jointed 

 bristles both long and short. His single example L. Isevis came from a gulf beyond 

 Guayaquil. 



Claparede 1 thought that the changes in the feet of the three genera, Mcon, 

 L&ptonereis, and Nicomedes proposed by Kinberg under his family Niconidea, were of 

 secondary importance, and he united them all under Leptonereis. 



Grube 2 likewise minimised Kinberg's group Niconidea, and placed his example under 

 Nereis (Leptonereis). 



1. Leptonereis Vaillanti, Be St. Joseph, 1888. Plate LXXXVI, figs. 9 and 9 a — bristles. 



Specific Characters. — Head large, rounded in front, typical in regard to appendages; 

 four large eyes with lenses ; buccal segment twice the breadth of the others ; four pairs 

 of tentacular cirri, short, and appearing from above to be cephalic in position. Body 

 15 — 20 mm. long, segments forty-eight to sixty, tapering posteriorly, and ending in two 

 bluntly conical processes closely applied to each other, and two slender subulate cirri 

 above them. Anus in front and dorsal to these processes. Colour pale rose with darker 

 touches. 



Proboscis has only a pair of well-developed maxillae with twelve to fourteen teeth. 

 First two feet have dorsal cirri, a pointed lamella beneath devoid of spine and bristles, 

 whereas all the other feet are complete, viz., dorsal cirrus, upper lamella, rounded 

 setigerous lobe with a black spine and homogomph bristles, whilst the inferior division 

 has a double setigerous region of a triangular shape, with two groups of bristles and a 

 powerful black spine. Upper group of bristles homogomph with some falcate hetero- 

 gomph, lower group with homogomph and a large number of heterogomph. Beneath 

 is an inferior lamella and a small ventral cirrus. 



Synonyms. 



1888. Leptonereis Vaillanti, De St. Joseph. Ami. Sci. Nat., 7 e ser., t. v, p. 246, pi. x, f. 113—123 



pi. xi, f. 124. 

 1909. „ „ Elwes. Journ. M. B. A., n.s., vol. viii, p. 351. 



Habitat. — A male heteronereid was found between tide-marks in February at 

 Oddicombe, Devon, by Major Elwes. 



Shores of Dinard, France (De St. Joseph). 



Head (Fig. 64) in the ordinary form (female nereid), according to De St. Joseph, 

 is large, rounded in front, with four large violet eyes with lenses, the anterior pair 

 elliptical, the posterior rounded. The buccal segment is twice the breadth of the others, 

 and the four pairs of tentacular cirri are short and appear from above to be almost 

 cephalic in position. 



Body is from 15 to 30 mm. long, and has from forty-eight to sixty segments. 



1 l Annel. Chretop. Nap./ SuppL, p. 90, 1870. 



2 l Annulat. Semper./ p. 61, 1878. 



