SCOUTING FOR GIRLS 
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SNAILS AND THEIR TRACKS ON THE SEA-BEACH 
of structure than there is between a horse and a hum- 
mingbird. The principal groups are: 
1. The Protozoa, or one-celled animals (nearly all 
microscopic). 
2. The Sponges. 
3. The Jellyfishes, Sea-anemones, and Corals. 
4. Worms of several groups. 
5. Starfishes, Sea-urchins, and Sea-cucumbers. 
6. Segmented Worms. 
7. Crabs, Lobsters, etc. 
8. Oysters, Snails, and Octopi. 
9. Insects and Spiders. 
Seashore Life 
Because of their connection with our industries or 
our food supply, some of the Invertebrates are familiar 
