158 TEREDINIDvE. 



plentiful and of a large size. None of the other ports 

 in the Bristol Channel are troubled with that or any 

 other species. The dispersion of mollusca is so wonder- 

 fully rapid, that in all probability a vessel wrecked any- 

 where on our coast, but not driven ashore, or a newly 

 erected submarine woodwork, will sooner or later attract 

 the wandering fry of some Teredo, which must have a 

 suitable nidus or prematurely perish. Or, as the whole 

 ocean teems with life in various states of development, 

 the germs of invertebrate animals (like the seeds of some 

 plants) may remain dormant for a long period, and only 

 become vivified when placed in favourable circumstances. 

 8. Economical relations to man. The new Salvage 

 Act has somewhat interfered with the liberty of con- 

 chologists in searching the shore for Teredines. Mr. 

 Dennis was more than once baulked in his hopes of 

 examining a promising piece of driftwood, seen floating 

 towards Beachy Head, by the coastguard marking it 

 with the broad arrow directly it reached the shore. A 

 douceur is consequently necessary to secure the prize of 

 a honeycombed ,log. If Crabbe were a living poet, he 

 could not now say of the naturalist, 



" His is untaied and undisputed game." 



The destructive nature of the Teredo is notorious ; 

 but we can hardly realize the extent of the damage 

 which these obscure miners perpetrate, by their stealthy 

 and incessant operations, when they attack our piers 

 and other submarine wooden structures. Quatrefages 

 asks us to imagine what would become of our trees and 

 furniture, and of the beams, joists, and rafters of our 

 houses, if they were to be gnawed by grubs measuring 

 a foot or more in length. However, no evil is unmixed 

 or without compensation. Smeathman, in his "Ac- 



