328 THE OCEAN WORLD. 
effected by the simple mechanical action of the “ hydraulic apparatus, 
rasp, and syringe.” : 
“If you examine the living molluscs,” says Gosse, “you will see 
that the fore part of the shell, where the foot protrudes, is set with 
stony points arranged in transverse and longitudinal rows, the former 
being the result of elevated ridges, radiating from the hinge, the latter 
that of the edges of successive growths of the shell. These points 
have the most accurate resemblance to those set on a steel rasp in a 
blacksmith’s shop. The animal,” Gosse adds, “turns in its burrow 
from side to side when at work, adhering to the interior by the foot, 
and therefore only partially rotating to and fro. The substance is 
Fig. 132.—Pholas papyracea (Solander). Fig. 133.—Pholas melanoura (Sowerby). 
abraded in the form of a fine powder, which is gradually ejected from 
the mouth of the hole by contraction of the efferent siphon.” 
The Pholads are met with on every sea-shore, and are plentiful 
in the Channel; on the French coast they are called Dazls, and 
sought for for their fine flavour. As examples of the genus, we may 
quote Pholas dactylus (Fig. 130); Pholas candida, found in the 
Channel and in the Atlantic Ocean, which lives buried in the mud 
or in decayed wood ; Pholas crispata (Fig. 131), also found in the 
Channel; Pholas iapyracea (Fig. 132); and Pholas melanoura 
(Fig. 133). 
The bodies of many genera of Mollusca have the property of 
shining in the dark, but none emit a light more brilliant than that of 
the Pholads. Those who eat the Pholads in an uncooked state 
(which is by no means rare, for the flavour of the mollusc does not 
