THE ORTHOPTERA OF MINNESOTA. 



47 



Fig. 19.—Harpalus herbivagus. 

 After Riley. 



Fig. 20. — Larva of 



Cryptohypnus bicolor. 



After Riley. 



Fig. 2OV2. 



Calosoma frigidum 



Natural size. 



Original. 



Still another coleopterous 

 larva is usually found in large 

 numbers; it is the larva of 

 Harpalus herbivagus Say, an 

 insect very abundant in fields 

 infested with locusts. It is 

 shown in Fig. 19. 



A verv interesting little cole- 

 opterous larva is also found 

 in considerable numbers inside 

 of the egg-pods of locusts. It 

 is shown in Fig. 20, and pro- 

 duces a small Click-beetle 

 [Cryptohypnus bicolor, Esch., 

 var. lacustris. 

 Numerous larvae of flies oc- 

 cur near the egg-masses, some of 

 which are known to be our friends. 



Very active and doing good work are 

 also the larvae of Calosoma frigidum 

 Kirby, and oiCalosomacalidum, Fab., 

 the former of which is only found near 

 edges of forests, while the latter oc- 

 curs everywhere in the prairies. The 

 mature beetles of these species feed al- 

 so upon the half-grown locusts. The adult 

 of Calosoma frigidum is shown in Fig. 20 V2. 

 This species possesses very different habits 

 from the other species of Calosoma, wath the 

 exception of scrutator. It climbs trees in 

 search of the caterpillars of Canker-worms, 

 and is as active in this work as the green 

 species, which, owing to its protective color, 

 is better equipped for such an arboreal 

 life. It would not be a bad idea to utilize 

 irio-idum in the war against the noxious 



