TEREBELLIFORMIA 



329 



teen gland shields are red, and continuous from segment to seg- 

 ment. The gill is shown in Fig. 176, C. North Sea, Atlantic, 

 and Mediterranean. 



Nicolea venustula Mont, has only two pairs of equal, arbor- 

 escent gills (Fig. 176, D); the tentacles are comparatively few. 

 The animal, which is about an inch in length, is cinnamon- 

 yellow with white spots, and has seventeen gland shields. 20 

 fathoms, North Sea and Mediterranean. Pista cristata MulL is 

 readily recognised by the shape of the gills (Fig. 176, E), of 

 which there are only two pairs. Each consists of a long peduncle, 



FIG. 176. Gills of various TerebellitLs. x 4. A, AmphitrUe johnstoni Mgrn. ; B, 

 Terebdla nebulosa Mont. ; C, T. conchilega Pall. ; D, Nicolea Mgrn. (the finer 

 branches are not indicated) ; E, Pista Mgrn. ; F, Terebellides Sars (after Mahu- 

 gren). g, Gill ; m, mouth ; t, tentacles. 



bearing a number of dichotomously dividing, rather spirally- 

 arranged branches, the whole having the appearance of a " bottle- 

 brush." The worm is 2 to 4 inches long, of greyish-red to yellow 

 colour. Atlantic east and west (even at the mouth of the Congo), 

 and Mediterranean. Thelepus cincinnatiis Fabr. is about the same 

 length, pale red in colour, marked on its back with clear areas, 

 giving the appearance of lacework. The gills are represented by 

 numerous unbranched filaments arising separately in two trans- 

 verse rows. The tube, which is adherent to shells, etc., along its 

 whole length, is of thin, transparent, and flexible material like 

 mica, covered with foreign bodies, and even with Polyzoa and 

 Hydrozoa. 30 fathoms, Atlantic and Mediterranean. 



