When the density of plant food, presented either as discs of lettuce Lactuca sativa, Potamogeton crispus, Groenlandia densa or as fronds of Lemna paucicostata was increased progressively from one to 16 or 32 units of weight, this was generally accompanied at each stage by an increase in the rates of ingestion, egestion, percentage assimilation and relative growth rates of the snails. Both net and
... [Show full abstract] gross production efficiencies showed converse trends. Although enhancement of snail growth with increase in food density is due in part to increased ingestion rate, exogenous plant factors are also implicated in promoting snail growth, at least in the case of lettuce.-from Authors