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College of Forestry 



that the mollusks outnumber the associated animals forming 

 57 percent of the total population. In Lower South Bay the 

 relative proportions are reversed, the mollusks forming but 

 42 percent of the total population. The large preponderance 

 of mollusks on the sand flat or shoal between the two islands 

 is striking. 



In addition to the young, immature and adult animals listed, 

 there were vast numbers of the eggs of mollusks and asso- 

 ciated animals which covered the vegetation in almost all 

 localities. This is especially true of the mollusks Amnlcola, 

 Gillia, Physa, and Lymncca. The eggs of gyrinid beetles were 

 also very numerous on water-lily leaves. Bryozoans {Pluma- 

 tella) thickly covered the submerged plants and bottom debris 

 in many places and sponges abounded on stones, plants, and 

 large objects. The Bryozoans and sponges probably have 

 some food value although this feature has not been definitely 



Table No. 41. Char.\cteristic Bottom Animals 



