MYTILIDiE. 
379 
able species of Cytlierea. In Fig. 172 we have the elegantly pencilled 
shell of Cytlierea yeoyraphica, together with the animal in its natural 
Acephales renferme. The 
kind of life of these molluscs is most singular. Not only do they bury 
themselves in the sand, as those do of which we have been speaking 
— they even excavate a dwelling for themselves in the solid rock of 
hardest stone, and even in wood. They may be called mining or 
boring molluscs— their labour, incessant, obstinate, slow, silent, and 
hidden, often causing terrible ravages in the constructions ol man. 
The Solens, or Kazor-fisli, are easily recognised by their elongated 
shell gaping at both extremities. These molluscs live bulled vertically 
in the sand, a short distance from the shore ; the hole which they 
have hollowed, and which they never quit, sometimes attains as much 
as two yards in depth ; by means of their foot, which is large, conical, 
swollen in the middle, and pointed at its extremity, they raise them- 
selves with great agility to the entrance of their hole. They bury 
themselves rapidly, and disappear on the slightest approach of danger. 
When the sea retires, the presence of the Solen is mdicated by a 
small orifice in the sand, whence escape at intervals bubbles ot air. 
In order to attract them to the surface, the fishermen throw into the 
hole a pinch of salt ; immediately the sand becomes stirred, and the 
animal presents itself just above the point of its shell. It must be 
seized at once, for it disappears again very quickly, and no renewed 
efforts will bring it to the surface a second time. 
This shell has by some been compared to a knife-handle ; by others 
to a razor, which has become its popular name. It is a thin, trans- 
parent, long and slender equivalved bivalve, with parallel edges, gaping 
and truncated at both extremities. The tints are rose-coloured, bluish 
grey, and violet ; the valves slightly covered with an epidermis of a 
greenish brown. 
connection. 
The last sections of 
Acephalous Molluscs 
which we shall notice are 
the Solens, Pholades, and 
Teredos, which have re- 
ceived from Cuvier the 
common designation of 
