Hienrnm Day. 
The Cockle. 
Structure.Mouth and stomach, foot, siphons, 
gills, manner of feeding and breathing; male and female 
cockles. 
Food of cockle—tThe cockle like the mussel 
and oyster feeds by “suction.” It gets its food from the 
diatoms and other microscopic life which are present in 
the water sucked into the shell by the action of the gills. 
These diatoms, &c., are to be seen in the intestine of the 
cockle, mixed with a great quantity of sand and mud. 
Exhalent 
2 = a 
ZY S 
*=74 Inhale 
ee Siphon 
Diagram of the structure of a Cockle. 
The Oyster. 
Structure of oyster 
heart. 
Manner of feeding and breathing. 
mouth, palps, gills, stomach, 
Male, female and hermaphrodite oysters. 
Different kinds of oysters—Deep-sea oysters, 
American oysters, Portuguese oysters. 
Tropical oysters, pearl oysters, pearls and pear! shells. 
Pearls in the common mussel. The parasite which 
is the cause of the pearls. 
Artificial cultivation of oysters in France. 
