184 MARINE INVERTEBRATES 



the first and the last three segments are bare, the rest have short bristles 

 above and hooks below; head has a prominent convex plate with a 

 raised border ; worm pale red, with bright-red bands around the seg- 

 ments, sometimes brownish. It constructs nearly straight tubes of pure 

 sand close to low- water mark in sheltered coves, and ranges from New 

 Jersey northward. 



GENUS Maldane 



M. elongata. Six to eight inches long, one eighth to one quarter 

 of an inch in diameter ; body cylindrical, cut obliquely at both ends ; 

 head bordered by a slight fold ; color brown, with red blood showing 

 through. Found in sandy mud at low-water mark, in firm, deep tubes 

 of fine mud, on the New England coast. 



FAMILY ARENICOUDJE 



GENUS Arenicola 



A. marina. Five to ten inches long; brownish-green; body cylin- 

 trical, thickest on the anterior end ; anterior and posterior ends without 

 ihaetae ; twelve to thirteen pairs of branched red gills on the central seg- 

 uents. It makes burrows eighteen to twenty-four inches deep on sandy 

 outhern shores, and can be traced by castings at the mouth of the bur- 

 bw. Commonly known as " lugworm," and used by fishermen for bait. 



FAMILY SABELLIDJE 



In this family the gills arise from two semicircular bases form- 

 ing the crown; the second lobe of the anterior extremity is 

 reversed like a collar; the gill-filaments have secondary pro- 

 cesses, and the tubes are flexible, composed of cemented mud or 

 sand. Found under stones, the tube passing around the stone 

 and opening upward. 



GENUS Sabella 



S. microplithalma. Length of tube one and a quarter inches, 

 diameter one eighth of an inch ; body olive-green, specked with white ; 

 wreath of tentacles half as long as the body ; tentacles pale yellowish 

 or flesh-colored, with transverse lines of darker color. It is found on 

 the southern New England coast. 



FAMILY SEEPUiiDa: 



This family forms white calcareous tubes. One of the dorsal 

 gill-filaments is flattened, forming an operculum, or cover, with 



