ANIMALS CLASSIFIED 3 
In the following pages directions are given for the 
laboratory study of the activities, as well as of the 
structure of the animals mentioned below. 
A paramectum, belonging to Protozoa. 
A sponge, belonging to Porifera. 
A hydra and a hydroid colony, belonging to Celen- 
terata. : 
A starfish and a sea-urchin, belonging to Echino- 
dermata. 
An earthworm, belonging to Vermes. 
A grasshopper, a butterfly, a house-fly, a potato- 
beetle, a spider, a centipede, and a crayfish or a lobster, 
belonging to Arthropoda. 
A mussel, a slug, and a snail, belonging to Mollusca. 
A fish, a frog, and a bird, belonging to Chordata. 
Directions for a short study of some domestic animals 
related to man are also given. 
