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Wisconsin Academy of Sciences, Arts, and Letters. 
THE AMOUNT OF FOOD EATEN BY THE SPIDER, 
ARANEA SERICATA 
Catherine Elizabeth Nebel. 
Introduction 
Though the kind of food that many animals eat has been ob¬ 
served, little is known in general concerning the quantity 
necessary for metabolism. This is true more or less of all in¬ 
vertebrates and of most vertebrates except the domesticated 
animals. It is therefore desirable that data be accumulated 
which will give accurate information on food requirements. 
This paper relates to the amount of food eaten by seven 
spiders (Aranea sericata McCook) and the amount gained or 
lost in weight by the same spiders from October 1, 1915 to Jan¬ 
uary 26, 1916. The spiders were collected in the green-house 
of the Biology building, University of Wisconsin, on Septem¬ 
ber 30, 1915. The food consisted of fruit flies {Drosophila 
ampelophila) raised on over-ripe bananas, and the spiders were 
fed daily. The experiments were performed in a north room 
of the biology building at a fairly constant temperature. 
Spiders were weighed once a week. 
According to McCook (’89) spiders usually seize their prey 
with the claws of the two fore pairs of legs. These are so long 
that they can be stretched out well in front of the body and 
grasp the insect without much danger in case the captured 
animal attempts to defend itself. 
Emerton (’83, 32-38) states that spiders sometimes chew an 
insect for hours until it becomes a round lump of skin, with 
all the juices extracted from it. It is then thrown away, the 
spider only swallowing such bits as may happen to be sucked 
in with the liquid portions. 
