Mr. Home on the Teredo Gigantea , &c. 277 
history of Sumatra, for further particulars respecting it. He 
introduced me to his friend Mr. Griffiths, who favoured Sir 
Joseph Banks with the account, which has already been laid 
before this learned Society, and also put into my possession a 
variety of specimens of the shell, to assist me in prosecuting 
the subject. 
There were no facts, by which the genus of the worm, to 
which this shell belongs, could be ascertained. Sir Joseph 
Banks, however, had no doubt of its being a teredo. This 
opinion rendered the subject still more interesting, since it 
does not, like other teredines, live in wood. The truth of Sir 
Joseph Banks’s opinion has been since established by the dis- 
covery of the two boring shells, and the two flattened oper- 
cula, which form the decided character of teredines ; these 
were found inclosed in one of the specimens. 
The internal structure and economy of teredines are so 
little known, and much of what is said of them by Sellius, the 
most classical author on that subject, is so vague, that it became 
necessary to acquire an accurate knowledge of the common 
teredo navalis, before any adequate idea could be formed of 
this new species, which may be called Teredo Gigantea. 
In this investigation the encouragement and assistance of 
Sir Joseph Banks were not wanting. By the kindness of Mr. 
Whitbey, Master Attendant at Woolwich Yard, and a Fellow 
of this Society, he procured pieces of wood from Sheerness, 
in which the animals were alive ; at his solicitation the Trus- 
tees of the British Museum permitted me, with their usual 
liberality, to examine a specimen of a teredo preserved in 
spirits of a very large size: and from the Hunterian 
