BEETLES WHICH DESTROY ALETIA. 



95^ 



( After 



Liun., P. pe7isylvanica, Liiin., and Priononyx thomcVj Fabr., are often 

 found in the cotton fields, and certain of tbem have been observed feed- 

 ing on the worms. Mr. Trelease has ob- 

 served PoUsfes helUcosa searching the 

 leaves for worms, and relying on the 

 tactile sense of the antennaj rather than 

 on sight to find them. The instant a worm 

 was touched, recognizing its enemy, it 

 would throw itself from the leaf, the Pol- 

 istes quickly springing after it. One wasp 

 was observed thus to spring eight times „ ,.^ ^ ,. , ^ „. 



^ ^ '^ Fig. 12.—Polistes belhcosa. 



unsuccessfully, the ninth time catching and Comstock.) 

 devouring the worm. Both species of Polistes were several times seen 

 flying about with dead caterpillars, having previously reduced them to a 

 pulpy mass with their mandibles. 



OoLEOPTERA, OR BEETLES. — Of this Order numerous species belong- 

 ing to the families of Tiger-beetles (Cicindelidw) and Ground-beetles ( Car- 

 ahidce) have been observed to prey upon the worms, each species being 

 represented by but a very small number of speci- 

 mens when compared with the ants. These beetles 

 9,re nevertheless among the most voracious insects 

 known to us. Most of them are nocturnal in their 

 habits, and are thus more apt to escape the attacks 

 of birds. They devour their prey bodily, and as 

 they are frequently met with in cotton fields very 

 remote from their hiding places, they are probably 

 attracted by the smell attending the worms. The 

 following is a list of the species actually observed ^i<^i3—Te«rac7iaiir^inica. 

 feeding thereon: Tetraclia Carolina (Linn.), T. virginica (Linn.), Cicin- 

 dela sperata Lee, Cicindela punctulata Fabr., Calosoma sayi Dej., Relluo- 

 morpha laticornis (Dej.), H, texana 

 Lee, Galerita atripes Lee, Bracli- 

 inus sp., Aphelogenia furcata (Lee), 

 Callida decora (Fabr.), Loxandrus 

 lucens Chaud., L. crenatus Lee, 

 Pterostichus sayi Brull., and Selen- 

 opliorns Icesus Lee The number of 

 Cicindela holes in the cotton fields 

 is astonishingly great, the most 

 abundant species being Cicindela s^!:^i(Z^1t^S!S!''^^Sti^2i:^^'''^^''' 

 pnnctulata. The larvae drag into their holes every Cotton Worm which 

 chances to crawl over the mouth, and many are thus destroyed during 

 the migration of the worms, towards the end of the season. Ordinarily, 

 however, the number of worms captured by these Tiger-beetles is very 

 small. The accompanying cut (Fig. 14) of Cicindela splendida from the 

 first report of the Commission will indicate the character of these tiger- 



