282 THE AQUARIAN NATURALIST. 



fans, towards the trowels ; while another organ, per- 

 haps the mouth, is also occupied, it may be, in com- 

 pounding the preparation with adhesive matter. As 

 the bulk of the muddy mass diminishes, the activity 

 of the worm abates ; it is soon succeeded by repose, 

 and then the tube is found to have received evident 

 prolongation. 



From the observations of Sir John Dalyell, it ap- 

 pears that the branchial fans of the Amphitrite, when 

 lost or mutilated, are, notwithstanding their com- 

 plicated structure, speedily reproduced and rendered 

 again efficient. 



AMPHITRITE BOMBYX. The Silk-worm Amphitrite. 



The general structure of this Annelidan resembles 

 that of the Amphitrite last described, both in the 

 worm-like organization of its body, and in the luxu- 

 riant plume of branchiae affixed to its anterior extre- 

 mity, as also in the circumstance of its inhabiting a 

 sheath or tube. This sheath, however, instead of 

 being constructed of foreign materials, is entirely 

 made up of an animal gluten, resembling silk, with- 

 out any earthy particles being incorporated in its 

 substance. The total length of this Amphitrite is 

 about 3 inches, whereof the plume, composed of about 

 sixty branchiie, constitutes a third, while the body 

 consists of sixty or seventy segments (PL V. fig. 8). 



The plume is proportionately larger and more luxu- 

 riant than that of the Amphitrite ventilabrum ; it is 

 finely variegated with different shades of brown and 

 yellow orpiment orange is the colour which pre- 



