LEPREA LAPIDARIA. 165 



Genus CLI. — Leprea, Malmgren, 1865. 



Heteroterebella, De Quatrefages ; Terebella, Hessle. 



Cephalic plate with a well-marked dorsal collar which joins the highly arched supra- 

 oral fold on each side. Ocular points conspicuous. Body typical, with setigerous 

 processes throughout. Twelve ventral scutes followed by a median glandular stripe. 

 Branchias three pairs, the first the largest ; each with a short stem, the terminal branches 

 both dichotomously and pinnately divided. Bristles commence on the fourth segment 

 and continue to the end of the body, have distinct wings minutely serrated; the tip 

 after tapering ends in a translucent knife-blade which again diminishes to a fine hair-like 

 extremity. Setigerous processes closely associated with the ridges for the hooks, which 

 commence at the first bristle-tuft. Hook has a large main fang and three teeth above it. 

 Anterior nephridia with long tubes ; the posterior nephridia are shorter and open into a 

 long canal terminating blindly posteriorly. 



1. Leprea lapidaria, Linnseus, 1767 (1754 Kdhler). Plate OXIII, figs. 3 and 3a — body; 



Plate CXXVI, figs. 8—8 b— bristles and hook. 



Specific Characters. — Cephalic plate produced anteriorly, thin, with eyes behind 

 dorsal collar. Tentacles pale yellow. Body 30 — 45 mm. long ; 100 — 124 segments, with 

 narrow rings and tessellated dorsally in front. Twelve ventral scutes followed by a 

 deep groove with a median raised line to the tail. Three branchia3 on the second, third 

 and fourth segments, first largest, each arising from a short stem which divides dicho- 

 tomously ; terminal processes dichotomously and pinnately divided, forming a finely ramose 

 bush. Setigerous processes with bristles on every segment from the fourth backward. 

 Small papilla (not always distinct) under each between the fourth and the tenth (eight in 

 all). Bristles in the anterior segments (11 — 15) with long, finely striated shafts and 

 winged tips, at the end of which is a slight spur or thickening followed by a finely 

 serrated blade which tapers to a hair-like point. The posterior bristles have very slender 

 shafts, no wings, and the tip appears as if bifid, since the two spurs are longer than in 

 front and support a serrated web, broad at the base and having no hair-like tip. 



Hooks in a single row in front, double row from the eleventh, and again in a single 

 row posteriorly (about twenty-five to forty segments, Marenzeller). 1 Each hook has three 

 teeth above the main fang. Colour reddish brown, inclining to purplish or violet on the 

 dorsum. Ventral shields and glandular plates red ; tentacles yellowish. Posteriorly the 

 body is orange or brownish orange. 



Synonyms. 



1 754. Eine neue Art Wasserpolypen, Kahler. Der K. Schwed. Akad. d. Wiss., etc., Aus d. Schwed. 



iibers. v. Kastaner, Bd. xvi, p. 143, Tab. hi, figs. A — f. 

 1767. Terebella lapidaria, Linnaeus. Syst. nat., edit, xii, t. i, pt. ii, p. 1092. 

 1806. „ „ Turton's Linn., p. 83. 



1 Lo Bianco states hooks commence on the fifth segment. 



