Compare also with the oyster and sea clam.
Examine empty shells and notice the pearly layer of the shell, the action of the hinge, and the marks on the shell to which the muscles for closing the shell were attached.
State all the means of protection that you have discovered the animal to possess.
BIRD STUDY
(Consult Bulletin 218. Birds of Ontario in Relation to Agriculture, Nash. Department of Agriculture, free.)
If the lessons in bird study which are prescribed for Forms I, II, and III have been successful, the pupils of Form IV should have a fair acquaintance with the habits of the common birds.
A very interesting exercise is to hold a trial upon those birds which are viewed with suspicion or which are openly condemned as objectionable neighbours. A pupil is appointed to act as judge and other pupils give evidence. The evidence must be based upon the pupil's personal observations on the habits of the bird.
The following birds are named, and brief descriptions of their habits are given as suggestions for materials for bird trials:
Robin.—He steals small fruits, such as cherries, currants, etc. He is a cheerful, jolly neighbour, who sings sweetly. He eats great numbers of cutworms and white grubs.
Crow.—He robs the nests of other birds, and steals chickens, corn, and potatoes. He helps the farmer by killing cutworms, white grubs, grasshoppers, and other insects.