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NEW YORK STATE MUSEUM 



very likely that they may render some service in checking the work of 

 injurious species in such situations. 



Another group of predaceous insects which is of considerable impor- 

 tance, is the dipterous family of fiower flies, Syrphidae. This contains a 

 large number of species and some are known to be exceedingly valuable 

 on account of their larvae preying on plant lice. The eggs are laid by 

 the female among prosperous colonies of these little insects and the young 

 hatching therefrom proceed to devour their victims, and when the flies are 

 at all abundant, the little pests are soon reduced to harmless numbers. 



Certain Hemiptera belonging to the family Pentatomidae, are well 

 known because of their fondness for other insects. The species of Podisus 

 and Euschistus, popularly known as soldier bugs, are sometimes present in 

 considerable numbers and undoubtedly render material aid in controlling 

 some injurious forms. The writer has observed Podisus placidus 

 Uhl., numerous in and about the nests of the apple tent caterpillar, 

 Malacosoma americana Fabr. These little bugs were seen to 

 attack caterpillars five times their size and slay them. As many as six or 

 seven were found within one nest and a number in the near vicinity. The 

 presence of this or related species in such large numbers means the 

 destruction of a great many caterpillars. 



There are some other predaceous insects in the north of less impor- 

 tance than those mentioned above. A number of species belonging to 

 the Hemipterous family Reduviidae are well known on account of their 

 living on other insects, and several members of this family have come into 

 prominence because of occasional bites inflicted on man. Several mem- 

 bers of the grasshopper order, Orthoptera, are beneficial on account of their 

 destroying various insects. The white flower crickets are common mem- 

 bers of this family and while the adults are injurious because of the punc- 

 tures they make in canes and small twigs, and holes in certain fruits, they 

 possess the valuable habit of devouring a great many small insects. 



The southern praying mantis. Stag mo mantis Carolina Linn., is 

 a well known southern species which preys on a great many insects, and the 



