220 AMPHITRITE. 



sive internal lining of gluten, much resembling the same that is used in 

 the arts, and capable of resisting rude external impressions. Its obvious 

 origin is an animal secretion, combined with mud or earthy matter. 

 After several months preservation in a dry state, a portion of the tube cuts 

 like very soft horn ; and the glutinous lining, half a line thick, yields in 

 combustion the odour of burning horn, accompanied by slight foetor. 



It is evident that the edifice can advance only when the entire 

 plume with the mechanical organization rises free above the orifice. The 

 bottom of the funnel requires to be about twice the diameter of the tube 

 above its edge, whence the tongue or scoop is always elevated for per- 

 forming its functions. Perhaps this organ and the trowels may be found 

 integral parts of the same apparatus. 



The office of the antennular prismatic spines in the centre of the 

 funnel is obscure. Rising erect, and apparently for some peculiar func- 

 tion during fabrication of the tube, particles of matter seem ascending in 

 contact with them, and sometimes pouring like a stream from their 

 points. 



The tenant seems totally dependent on the presence of mud for en- 

 larging its habitation, and it is surprising how speedily a quantity ac- 

 cumulates in the centre of the funnel previous to commencing its revo- 

 lution, demitting the preparation between the trowels, and pasting it 

 around the orifice. 



Surely the presence of the suspended muddy matter is very grateful 

 and inviting. It seems to arouse the dormant faculties of the humble 

 artists, and to excite their energy while lurking for a season within their 

 tubes in languid quiescence. No sooner is the water rendered turbid, 

 than they issue forth and begin their architectural preparations. 



Perhaps some secret necessity urges constant prolongation of the 

 dwelling, whether for security, or for advancing increment. Should the 

 animal be alarmed during its preliminary collections, it vanishes in a 

 moment ; the muddy aggregate discharged by collapse of the branchiae fall 

 useless among the surrounding element. But if a feather, now dipped 

 in mud, be first plunged among the water of another vessel, to separate 

 the grosser parts, and afterwards in that which contains the Amphitrite, 



