\ 



^ 156 SEDENTARIJE. 



f 



attenuated behind, with many aimulated segments ; and a single 

 row of setiferous papiiiae.bristles subulate, fasciculateand hooked 

 setae ; branchiae in slender finger-shaped fasciculi, disposed like 

 a fan, and spreading into a disk •, two short subulate filaments 

 inserted at the internal base of the branchioe, between which is 

 a terminal mouth ; tube elongated, cylindrical, tapering towards 

 the base, membranous or coriaceous and generally naked. 



Amphitrite ventilahrum. — The Fan Amphitrite. Plate 

 XIX. fig. 19. Tube tapering, incurved, and smooth ; of a 

 cream yellow colour. Inhabits the Mediterranean sea. 



Genus 7.— TEREBELL A.— Lamarc/f. 



Generic Character.— Body tubicular, elongated, cylindrically 

 depressed, attenuated posteriorly, segments transverse, and sub- 

 annulated ; having a row of nodulous and setiferous papillae on 

 each side; with numerous filiform, twisted tentacula surround- 

 ing the mouth, and terminating in front of it ; two rows of 

 ramose branchiae placed in a single row beneath the tentacula ;; 

 tube elongated, cylindrical, attenuated and pointed at the base, 

 membranous, consisting of agglutinated grains of sand and frag- 

 ments of shells. 



Terebella conchilega. — The Shelly Terebella. Plate 

 XIX. fig. 21. Tube covered with numerous fragments of 

 broken shells agglutinated together ; with three branchiae on 

 each side. Inhabits the coasts of Holland. 



** With short branchiaj ; tentacula short or awanting. 



Genus 8.-SABELLARIA.— ZamarcA'. 



Generic Character. — Body tubicular, subcylindrical, attenua- 

 ted behind ; with fasciculi of subulate bristles in a single row on 

 each side, and spatulous bristles and transverse laminae, armed 

 with hooked setse ; anterior extremity obliquely truncated, ellip- 

 tical, surmounted by six rows of brilliant spangles, three rows 

 on either side ; mouth elongated, cleft, with two lips, the 

 under one short and internal ; with smaK branchiae placed near 

 the mouth ; tubes numerous, congregated in a common mass, 



