EXERCISE V. 
THE COCKLE (Chione stutchbury?). 
Sub-hkingdom—MO.Luusca. Class —LAMELLIBRANCHIATA. 
1. Hold the animal in the hand, and with a blow of a. 
hammer break one valve of the shell inte three or 
more pieces. Remove any portions of the shell that 
may be loose. With the handle of a knife detach 
the mantle from the broken valve; then cut the 
attachments of the adductor and pedal muscles close 
to their attachments to the broken valve, and remove 
all portions of the broken valve. In this operation, be 
particularly careful in cutting the anterior adductor 
muscle, not to cut into the mouth. Fix the unbroken 
valve to a cork by means of pins, and braces formed 
by bent pins, and, if the water contained in the shell 
has been spilt, fill up the valve with sait water. 
Turn it so that the hinge of the shell is away from 
you. 
2. Notice the mantle, or pallium, with its thickened 
border. The two siphons, margined with tentacles— 
the siphonal tentacles—at the posterior end of the — 
animal. They are formed by the produced border of 
the mantle, and are united together at their bases. 
The ventral siphon—.e., the one nearest you—is the 
inhalent, and the dorsal one is the exhalent siphon. 
3. Lift up the lobe of the mantle with a pair of forceps, 
and with the scissors cut it completely off, leaving 
