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THE MOLLUSKS 
SUMMARY 
The parts of mollusks are not arranged in segments 
like the earthworms or crustaceans. The usual presence 
of a shell and mantle and the fact that the soft body is 
not divided into segments helps to distinguish a mollusk 
from any other animal. The microscopic food of the 
clam is caught in the mucus and carried by cilia to the 
mouth. The clams and oysters are valuable for food but 
should not be eaten if taken from water contaminated by 
disease germs. Mollusk beds should be protected from 
such contamination. 
QUESTIONS 
What are some of the common mollusks? Where do they live? 
How do they get their food? What ones are used for food by man? 
REFERENCES 
Brooks, The Oyster. 
Cambridge Natural History, Vol. III. 
Kellogg, The Shellfish Industries. 
Linville and Kelly, Zoology. 
