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College of Forestry 
4, Prepacrous MoLuvsks. 
Lymnea stagnalis lillianew Baker. Lallian’s Pond-snail. 
In the previous pages reference has been made to the 
use of Planorbis campanulatus by this snail as food. No 
other records have been observed, excepting that of Cooke 
(1895, p. 34) who remarks that Lymnea stagnalis feeds on 
Dytiscus larvee, snails and minnows. Other Lymnzeas possi- 
bly eat mollusks to some extent. 
5. AMPHIBIAN ENEMIES oF MoLuusks. 
Aquatic amphibians, frogs, newts and salamanders, feed 
to a greater or less degree upon mollusks. Some of the 
records are very satisfactory as regards detail, but others are 
very general. 
Rana catesbiana Shaw. Bullfrog. 
Needham (1901, p. 401) records the food of one adult 
bullfrog to be 7 full grown snails, Physa heterostropha, 7 in- 
sects, I small bullfrog tadpole, 1 entomostracan. Expressed 
in percentages, the molluscan content amounts to about 40 
per cent. Hay (1892, p. 479) gives the food as crawfish, 
insects, worms, small fish, snails, mice, and its own species. 
Two specimens, collected on the shore of Oneida Lake, 
October 9, 1914, were dissected, but no mollusks were found 
in their stomachs. The data for these appears below (field 
No. 4): 
No. 1. Stomach filled with small seeds of plants. 
No. 2. Stomach contents. 
Repbilia. | 2ortion on a snakerre. 4h eeee ade 75 per cent. 
Plants. Fragments of leaves and stems...... 25 per cent. 
Rana pipiens Shreber. Leopard Frog. 
Drake (1914, page 263) gives the mollusean food of this 
common frog as 3 per cent. The stomachs of 209 frogs were 
examined and Mollusca-were found in 10 per cent. of the 
stomachs examined. Insects made up about 60 per cent of 
the total food. The mollusks identified were Zonites 
