CG Avie Ti 1X 
INSECTS IN RELATION TO OTHER ANIMALS 
1. THE GENERAL SUBJECT 
On the one hand, insects may derive their food from other 
aninals, either living or dead; on the other hand, insects them- 
selves are food for other animals, especially fishes and birds, 
against which they protect themselves by various means, more 
or less effective. These topics form the principal subject of 
the present chapter. 
Predaceous Insects.—Innumerable aquatic insects feed 
largely or entirely upon microscopic Protozoa, Rotifera, Ento- 
mostraca, etc.; this is especially the case with culicid and chi- 
ronomid larve. Many aquatic Hemiptera and Coleoptera 
prey upon planarians, nematodes, annelids, molluscs and 
crustaceans; Belostoma sometimes pierces the bodies of tad- 
poles and small fishes; Dytiscus also kills young fishes occa- 
sionally and is distinctly carnivorous both as larva and imago. 
Among terrestrial insects, Carabidze are notably predaceous, 
preying not only upon other insects but also upon molluscs, 
myriopods, mites and spiders. Ants do not hesitate to attack all 
kinds of animals; in the tropics, the wandering ants (Eciton) 
attack lizards, rats and other vertebrates, and it is said that 
even huge serpents, when in a torpid condition, are sometimes 
killed by armies of these pugnacious insects. 
Mosquitoes affect not only mammals but also, though 
rarely, fishes and turtles. The gad flies (Tabanidz) torment 
horses and cattle by their punctures; and the black-flies, or 
buffalo gnats (Szmalitm), persecute horses, mules, cattle, 
fowls, and frequently become unendurable even to man. The 
notorious tsetse fly (Glossina morsitans) of South Africa 
spreads a deadly disease among horses, cattle and dogs, by 
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