THE TEREBELLA. 423 



more rapidly, and as if they had some purpose to fulfill. In the 

 evening the worm is in full work ; and as Professor Rymer Jones 

 has given a clear and graphic description of its proceedings, I can 

 not do better than transfer his account to these pages. After re- 

 marking on the general habits of the creature, and describing the 

 tentacles, he proceeds as follows : 



" They," i. e., the tentacles, " are now spread out from the orifice 

 of the tube like so many slender cords. Each seizes on one or 

 more grains of sand, and drags its burden to the summit of the 

 tube, there to be employed according to the service required. 

 Should any of the tentacula slip, the same organs are again em- 

 ployed to search eagerly for the lost portion of sand, which is 

 again seized and dragged toward its destination. 



" Such operations are protracted during several hours, though 

 so gradually as to be apparently of little effect; nevertheless, on 

 resuming inspection next morning, a surprising elongation of the 

 tube will be discovered ; or, perhaps, instead of a simple accession 

 to its walls, the orifice will be surrounded by forking threads of 

 sandy particles agglutinated together. 



"The architect has now retired to repose; but, as evening 

 comes, its activity is renewed, and again at sunrise a farther pro- 

 longation has augmented the extent of its dwelling. 



" At first sight the numerous tentacula seem only so many long, 

 cylindrical, fleshy threads of infinite flexibility. 



" On examining them, however, more attentively, we see that 

 in exercising their special function, the surface which is applied to 

 the foreign objects becomes flattened into twice or thrice its ordi- 

 nary diameter; and while conveying the sandy materials to the 

 tube, these are seized and retained in a deep groove, which almost 

 resembles a slit; in fact, the tentaculum becomes a flat, narrow 

 ribbon, folding longitudinally in different places to hold the par- 

 ticles securely. 



"Although these organs, when contracted, are collected into a 

 brush scarcely double the thickness of the animal's body, so enor- 

 mous is their extensibility that they can be stretched out to the 

 length of four inches, or half the length of the body, thus sweep- 

 ing the area of a circle eight inches in diameter. 



"A thin internal coating, resembling silk, lines the whole tube, 

 and at the same time serves as a real cement to unite and strength- 

 en its innumerable parts. This silk-like material is derived from 

 a glutinous slime, which exudes from the surface of the body of 

 the Terebella. 



