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XIX. Descriptions of Jive British Species of the Genus Terehella 

 of LinnL By the late George Montagu, Esq. F.L.S. Commu- 

 nicated by William Elford Leach, M.D. F.R.S. and L.S. 



Read March 4, 1817. 



TEREBELLA. 



Gen. Char. Body long and annulated, furnished on each side 

 ■with pedunculated feet terminated with bristles, which are 

 retractile : head with numerous long simple capillary appen- 

 dages : three small ramified branchiae on each side behind 

 the head. 



The animals of this genus either prepare a sheath from the te- 

 nacious secretion of their bodies mixed with adventitious matter, 

 or reside in prepared perforations at the bottom of the sea. The 

 tubes which are prepared by them are in general so extremely 

 delicate, that they are very easily destroyed, and they are then 

 found lurking beneath stones, or forming a new habitation by 

 connecting together sand or mud with the slimy secretion of their 

 bodies. Some species form a tube in old shells or stones, to 

 which they adhere by the whole length; others fix a tube per- 

 pendicularly in the sand, with two or three inches projecting 

 above the surface. Many are gregarious, and so numerous, that 

 we have seen the shore covered with the fragments of their tubes 



after 



