COLORADO POTATO-BEETLE. 65 



• Of these insects, the first five are ground beetles, and are pre- 

 daceous both in the larva and perfect states, and they devour the 

 Potato-beetles and their larvae, mostly on the ground or whilst 

 undergoing their transformation beneath the surface. 



The next three attack them on the vines. 

 ■ The next four belong to the family of Lady-bugs and help to 

 destroy the Potato-bugs by eating their eggs. 



The four Hemipterous insects are all predacious. They attack 

 the Potato-bugs wherever they can find them and kill them by 

 puncturing them with their beaks and extracting their juices. 



No. 17 is a large, savage two-winged fly, which, it would 

 seem, attacks almost any insect that comes in its way. Its specific 

 name means bee-eating, and it is the same insect which has been 

 called the Nebraska Bee-killer. It also kills Horse-flies, and now 

 it is proved to add the Potato-beetle to its indiscriminate bill of 

 fare. I received a pair of these insects from Mr. A. R. Whitney, 

 of Franklin Grove, who caught them in the act of seizing and 

 carrying ofl' the mature beetles. These ferocious insects resemble 

 the hawk in their mode of dealing with their prey. They seize 

 it, fly ofi" with it for a short distance and then alight and devour 

 it at their leisure. Whilst so engaged they allow themselves to 

 be approached quite nearly, and are easily captured. Mr. Whit- 

 ney followed a number of them, and got possession of the beetles, 

 which he always found dead by the time he could reach them. 



No. 18 is a parasitic fly, belonging to the family of TachinidcB 

 the larvae of which live in the bodies of the Potato-bugs, and thus 

 destroy them. It was actually bred by Mr. Riley from the infested 

 insects, and I have several times seen this fly or another similar 

 species alight upon the vines in the midst of the beetles and their 

 larvte. 



No. 19 is commonly known as the Daddy-Long legs, and I place 

 it in the list of Colorado Potato-bug destroyers on the authority of 

 Mr. Arthur Bryant, as given in the Transactions of the Illinois 

 Horticultural Society, Yol. I, page 102. To this list may be added, 

 though with some doubt, the Little-lined, or Tarnish Plant-bug 

 {Capsus linearis). Early in the season, I received a letter from 

 Mr. James Taylor, of Somonauk, in which, amongst other matters, 

 he spoke of a small insect which pierced with its beak and de- 

 stroyed the eggs of the Colorado Potato- beetle. As I could not 

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