PLATE CXLV, 



Dentalium testa metnbranacea cylindracea, ligno inserta. Linn. Fn. 



Snec. I. p. 3&O.No. 1329. 

 Serpula testa cylindracea flexuosa, lignum perforans. Teredo. Da 



Costa. Brit. Conch, p. 21. sp. II. 



Sellius Hist. Nat. Tered. B aster , Phil, trans. 61. 

 Teredo navalis. Ship-worm. Penn. Brit. Zool. 4. No. 160. 



This destructive creature is supposed to have been originally a, 

 native of the East-Indies, and from thence introduced into the Eu- 

 ropean seas : at present it may be considered with propriety as a 

 naturalized British species ; and it is a fortunate circumstance that it 

 does not thrive so well with us as in warmer climates. 



The animal, a soft and almost shapeless gelatinous body, is fur- 

 nished with a calcareous process, or augur, at the head, with which 

 it bores with the utmost facility into the stoutest oaken plank, as it 

 lies in the water ; and where a number of them attack the same piece 

 of wood, will in a few days entirely destroy it : hence the ravages 

 of these animals in the bottoms of ships are fraught with the greatest 

 danger; and notwithstanding all the precaution of sheathing the 

 bottoms of ships with copper, they insinuate themselves through the 

 smallest cavities, and lodge themselves securely in the timbers. 

 Where the work of the animal first commences, the shell is obtusely 

 rounded and closed, and as it proceeds it continues to lengthen its 

 shell till, as Gmelin says, it becomes from four to six inches in 

 length ; — we have seen one of them whose progress through the solid 

 plank had not been interrupted, that had grown nearly to the length 

 of eighteen inches. It is said that sheets of paper dipped in tar, and 

 applied to the ship's bottom, will prove a more effectual preservative 



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