AMPHITRITE OSTREARIA. 305 



used for fastening this web, are at all obvious. This 

 is, however, plainly a work of some exertion, as the 

 threads, sometimes amounting to fifty, are fixed to 

 the side of the vessel as high above the bottom as 

 equals the length of the ' ' Weaver" or more, and they 

 also extend below, there to be secured. Thus it is 

 evidently an artificial work, and it receives successive 

 additions. 



Such a web, however, seems only to be constructed 

 during the month of May, and appears specially 

 destined to the reception of the eggs, which about 

 this time are deposited. 



AMPHITRITE OSTREARIA. " The Oyster Amphitrite." 



The word Terebella, literally translated, would seem 

 to signify a creature endowed with the faculty of per- 

 forating rocks and other hard substances, a name by 

 no means applicable to the animals we have been de- 

 scribing under that appellation. Nevertheless, there is 

 one exception to be found in a very small Annelidan, 

 bearing some remote kindred to the Terebella, which 

 seems to have the power of excavating a burrow for its 

 own lodgement, even in so hard a substance as shell. 



While inspecting the exterior of old oyster-shells, 

 the observer may sometimes see several slender, 

 brownish tentacular organs playing around a fixed 

 point, and occasionally withdrawing themselves from 

 view. On separation of the laminae and breaking 

 down the shell, an Annelide, from which they pro- 

 ceeded, is discovered lurking in a cavity in the midst 

 of its solid substance. 



