TEREDINA, 



Lmn» * 



TESTA crassa, fistulosa, antice sensim attenuata, 

 aperta, apertura clissepimento subdivisa, oper- 

 culo unico nonnunquam occlusa, postice omnino 

 clausa, valvis duabus (ut in Teredinibus con- 

 form atis) in extern o tubi pariete conferrumi- 

 natis, intus dente recurvo majore instructo ; 

 valva accessoria subquadrata umboni antice 

 superiinposita. 



A very singular Genus only known in a fossil state, be- 

 longing to the Tuhicolce of Lam. and approaching in its 

 characters to Teredo, In consequence of its general 

 resemblance to that genus, we were at first disposed to 

 have united them together, joining to them the Fistulana 

 gregata of Lam. ; but as the tube in Teredina never covers 

 the two valves, but appears to be soldered to them, as 

 in Aspergillum, we are constrained to regard it as a dis- 

 tinct Genus ; of which, however, we only know one species 

 at present, namely the T. per sonata of Lam, for we have 

 already ventured to express our opinion that the shell des- 

 cribed by Lam. under the name of T, Bacillum is not a Tere- 

 dina, but may more properly be considered as a Saxicava. 

 In many respects Teredina personata resembles the Pholas 

 papyracea of Turton, and in others the Ph, striata of Linn. ^ 

 from the latter, however, it differs in having a shelly tube 

 which that has not, and from the former in having aa 

 operculum to cover the posterior aperture of the tube. 



Shell consisting of a thick fistulous tube, smaller 

 at the posterior end, which is open, nearly divided into 

 two by a projection on each side within, and has an 

 operculum, as we are informed, though we have never 

 seen it, which covers the double opening : it is remark- 

 able that the posterior smaller portion of the tube is of 

 a very different substance and colour from the anterior 

 and larger termination 3 it resembles horn in appearance 



