38. Lysidice robusta. Body much thicker than is usual in the genus ; very 

 convex above, and flat below ; of a copper color. Rings very closely-set, about 

 one hundred and twenty in number. Head concealed, but provided with three 

 conspicuous, tri-articulate tentacula, and with two large rounded lobes below. 

 Proboscis very short ; jaws very strong, calcareous externally, corneous within. 

 Neck equalling the succeeding two rings together in size. Pinnae very small ; 

 superior cirrus large, inferior one short ; superior setae capillary, lanceolated but 

 tapering to a long hair-like extremity ; inferior ones falcate with short smooth 

 terminal joints ; acicle blunt, of a dark-brown color. Length, 2.8 inches ; 

 breadth, 0.15 inch. Found under stones near low-water mark. 



Hab. Australia, at Port Jackson. 



39. Nereis mendax. Small, rather slender, largest anteriorly, flattened pos- 

 teriorly. Head elongated, narrow, with the terminal tentacles well developed 

 and extending somewhat beyond the thick inferior ones ; tentacula cirri very 

 slender, variable in length, but usually reaching beyond the tentacles ; eyes very 

 conspicuous, the posterior ones largest and nearest to each other. Pinnse rather 

 large, anterior ones with pointed lingulae, and dorsal and ventral cirri ; in the 

 posterior pinnas the superior lingula loses its cirrus, and expands into a broad 

 lamella. Color variable ; pale red, or brownish, often farinaceous posteriorly ; 

 always with a dorsal line of flake-white, and a white spot between the eyes. 

 Length, 1.5 inches; breadth, 0.2 inch. It inhabits a tube. Common in the 

 circumlittoral zone. 



Hah. Cape of Good Hope, at False Bay. 



40. Nereis operta. Large, of an uniform dark sepia color above, paler be- 

 low and posteriorly. Head short, eyes nearly hidden under the integument ; in- 

 ferior tentacles extending beyond the others. Anterior pinnae with blunt lin- 

 gulae, large superior cirri, and very stout inferior setae. Posteriorly the cirri are 

 reduced, the superior lingula compressed and slightly expanded, bearing the cir- 

 rus upon its upper edge. Maxillae broad, little curved, and nearly smooth on their 

 inner edges. Length, 4 inches ; breadth, 0.35 inch. Found among rocks at 

 low-water mark. 



Hah. Cape of Good Hope, at Simon's Bay. 



41. Lepidonote semitecta. Scales about twelve in number on each side, so 

 small as to reach each other without overlapping and to leave the middle of the 

 back bare. Head quadrangular with four minute eyes ; and five tentacles, the 

 median largest, the exterior ones longer than the intermediates, but like those 

 aanulated with black. Lateral cirri short, each with a black ring near its tip. 

 Color greyish-crimson, with black dots along the middle of the back. Scales 

 bright crimson, except at their attachments where they are white. Length 1 

 inch ; breadth, 0.3 inch. Found at low-water mark, in the circumlittoral 

 zone. 



Hah. Cape of Good Hope, at Simon's Bay. 



CHORISTOPODA. 



42. Anthura polita. Cylindrical, smooth and shining; the seventh segment 

 nearly as large as the sixth. Head small, inferior antennae as long as the head, 

 somewhat larger than the superior ones and placed before them ; eyes very mi- 

 nute, black, placed rather on the sides of the head at the anterior corners. Legs 

 of the first pair very thick, the rest slender. Abdomen short and broad. Color 

 pale greyish, mottled. Length, 0.9 inch; breadth, 0.13 inch. Found at 

 the depth of two inches in sand, above half-tide. 



Hab. Coast of the United States, at Norfolk. 



43. Anthura punctata. Anterior segments elongated and slender, the sixth 

 broadest, the seventh very short, and bearing a much smaller pair of legs than 

 the others. Head scarcely narrower than the first thoracic segment, with a 

 slight rostrum, and large black eyes at the anterior corners ; the inferior an- 



