[381] INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. S7 
The destructive habits of this species were first brought prominently 
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 investi- 
gated 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.” 
The remedies used to check its ravages are chiefly copper or other 
metallic sheathing; driving broad-headed iron nails, close together, 
into the part of the piles subject to their attacks; and applying coal- 
tar, creosote, or verdigris-paint, once a year or oftener. 
Another singular crustacean, common on the piles at Wood’s Hole, 
is the Tanais jfilum. This is a very slender, whitish species, almost 
thread-like in form, but has the first pair of legs much thickened, with 
very peculiar, stout claws, ovate in form; the rest of the anterior legs 
are very slender. The antenne are short and thick, the inner ones di- 
rected forward; the outer ones more slender, and curved outward and 
backward. This species lives among the adhering ascidians and hy- 
droids on the piles, and has also been found in deeper water, in the Bay 
of Fundy. Its habits are little known, but some of the allied species 
have been accused of boring in wood. 
Two species of barnacles are very common on the piles of the 
wharves. The common barnacle of the rocky shores, Balanus balanoides, 
(p. 305,) is also common on the piles of wharves and bridges, between 
tides, and also on the bottoms of vessels, &c. It never grows very 
large, although it may become so crowded together as to form a contin- 
uous crust. It is easily distinguished from the other species by its 
membranous base, which never forms a solid plate, like that of the 
other species. The “ivory-barnacle,” Balanus eburneus, is also common 
on all kinds of submerged wood-work, whether fixed or floating. . It 
is usually abundant on the piles and timbers of wharves, buoys, oyster- 
stakes, bottoms of vessels, &c. It is chiefly found below low-water 
mark if on fixed objects, and is even more common in the brackish 
waters of estuaries than in the purer waters outside, and it is capable 
of living even in pure fresh water, for Professor Jeffreys Wyman has 
sent me specimens collected, by himself, about sixty-five miles up the Saint 
John’s River, in Florida, where the water is not at all brackish. This 
species is sometimes found adhering to the carapax of crabs, the 
shell of Limulus, and various mollusks. It is easily distinguished from 
most species on account of its low, broad form and its smooth white 
exterior. It hasashelly base. The BL. crenatus, common on shells and 
stones in deep water, also occurs on vessels. Other species are often 
found on the bottoms of vessels that have come from warmer latitudes. 
Some of them are of large size. One of the most frequent of these is 
Balanus tintinabulum. 
Several species of “ goose-barnacles,” Lepas, are frequently found 
