366 TEREDO NAVALIS IN KOVA SCOTIA — MURfHY. 



great losses are sometimes caused in this way. Complaints of 

 such ravages in the Navy Yard at Portsmouth, New Hampshire, 

 have been made, and they also occur at the Charlestown Navy 7 

 Yard, and in the piles of the wharves at Boston. Probably the 

 wharves and other submerged wood-work in all our sea ports, 

 from New York northward, are more or less injured by this crea- 

 ture, and if it could be accurately estimated, the damage would 

 be found surprisingly great. 



" Unlike the Teredo, this creature is a vegetarian, and eats the 

 wood which it excavates, so that its boring operations provide it- 

 with both food and shelter. The burrows are made by means of 

 its stout mandibles or jaws. It is capable of swimming quite 

 rapidly, and can leap backward suddenly by means of its tail. 

 It can creep both forward and backward. Its legs are short and 

 better adapted for moving up and down in its burrow than else- 

 where, and its body is rounded, with parallel sides, and well 

 adapted to its mode of life. When disturbed it will roll itself 

 into a ball. The female carries seven to nine eggs or young in 

 the incubatory pouch at one time. 



" The destructive habits of this species were first brought pro- 

 minently to notice in 1811, by the celebrated Robert Stephenson, 

 who found it rapidly destroying the wood work at the Bell Rock 

 light house, erected by him on the coast of Scotland. Since that 

 time it has been investigated, and its ravages have been described 

 by numerous European writers. It is very destructive on the 

 coasts of Great Britain, where it is known as the " gribble." 



If we contrast the destructive powers of the two most remark- 

 able wood borers inhabiting our shores we find a great diversity 

 in size, form, mode of operation, mode of existence and attack. 



The Teredo, as we find it, is from four to six inches long, and 

 about £ to \ inch in diameter. The Limnoria is about 1-16 to 

 1-8 of an inch in length, and about one half that thickness. The 

 Teredo is long and vermiform ; the Limnoria is short and ovate. 

 The Teredo bores to make itself a house. The Limnoria bores for 

 existence. The Teredo lives on the infusoria of the water : 

 the Limnoria on the substance of the wood itself. 



The Teredo attacks from the outside, and penetrates into the 



