TEREBELLA. 185 
suits, where an hour's interval may produce an absolute deformity of 
what has been beheld as beautiful and symmetrical. Description is a 
very unsatisfactory substitute for representation, as all who study nature 
in her own garb will agree. Nor can any system be useful, abounding 
in conviction throughout, intelligible and agreeable, unless accompanied 
by figures of the subjects as beheld in their ordinary form. 
The two genera more commonly confounded are the Terebella and 
Amphitrite, though corresponding somewhat in general character, are 
radically distinct in themselves. It would be difficult to point out the 
grossest errors of recent authors or editors in this respect, themselves 
utterly to blame, while attempting to blame their more correct fellows. 
§ 1. TEREBELLA LITTORALIS, SEU ARENARIA— The Sand Mason.—Plate XXVI. 
Figs. 1, 2, 3, 4, 5, 6, 7. 
Between half-tide and low-water mark numerous cylindrical tubes 
may be observed projecting from among the rocks and stones of the 
shore, especially amidst sandy patches. Some terminate ina tuft, like the 
oozing end of a hempen cord, and on a search being made in the neigh- 
bourhood, another of corresponding appearance, or the orifice of a plane, 
hollow, sandy cylinder, will be frequently found within a short distance. 
Here is the dwelling of the Terebella, an edifice constructed by itself. 
If the finder endeavours to pull forth the tube with its tenant, it ruptures 
in his hand, and the animal retreats below, but on tracing its direction, as 
it winds a foot or more among the sand, or descending under one of the 
firmest stones in the vicinity, he may discover the orifice rising on the 
opposite side. 
Now it may be removed along with the architect, which meantime 
has contracted within the smallest possible space. The naturalist must 
never forget the importance of obtaining every subject entire and unmuti- 
lated, which will cost him much time and patience on many occasions. 
But the first consequence of this oversight would probably be the vitia- 
tion of the water, from the decomposition of the injured parts or por- 
tions, and the death of the remainder. 
