﻿OF THE STATE ENTOMOLOGIST. 17 



NATURxVL ENEMIES. 



It is not probable that any of the natural enemies which attack 

 this insect in Europe have been imported with it into this country; 

 but several of our indigenous species have learned to prey upon it. 

 Besides such indiscriminate feeders as ants and some of the cannibal 

 beetles which Mr. Saunders has observed to attack the worms when 

 they fall from the bushes, or are the least helpless or injured, it is 

 attacked while on the bushes and in vigorous health by a Half-wing 

 Bug, first noticed at this work by the same gentleman. This species 

 {Podisus placidus Uhler, Fig. 7, a, enlarged; 5, natural size) which 

 may be called the Placid Soldier-bug, is marked with yellowish-brown 

 [Fig. 7.] and dark brown, and attacks the worms in the same 



well known manner in which the Spined Soldier-bug 

 spears and sucks to death the larvas of the Colorado 

 Potato-beetle. Mr. Walsh bred from this Currant 

 worm a small Ichneumon-fly {BracJujpterus microp- 

 terus^ Say) which has such small wings that it much 

 resembles an ant. Mr. C. J. S. Bethune also reared 

 from its cocoon another Ichneumon-fly {Ilemiteles 

 nemativorus^ Walsh)* closely allied to that which 

 infests our common Bag Worm (Rep. I, p. 150.) This 

 Placid soldiee-bug: same fly was captured a number of years ago by Mr. 



a, enlarged ; h, natural 



size. Walsh around Rock Island, Illinois, " and as the Im- 



ported Currant Worm has not as yet been introduced into that region, 

 we must conclude that this Ichneumon-fly could not have been 

 imported into America from Europe along with this Currant Worm, 

 but that in all probability it is an indigenous species. Hence we have 

 additional proof that, under certain circumstances, native American 

 parasites can, and actually do, acquire the habit of preying upon 

 European insects when the latter are imported into America. It is 

 certain, however, that they will not do so in all cases without excep- 

 tion ; for although the Wheat Midge, or Red Weevil, as it is incorrectly 

 termed in the West, invaded our shores some forty or fifty years ago, 

 not a single parasite has yet been discovered to prey upon it in this 

 country, although there are no less than three that prey upon it in 

 Europe." 



Lastly, Mr. J. A. Lintner has discovered that even the eggs are 

 inhabited by a minute llymenopterous parasite which, I believe, 

 remains undescribed ; and he informs me that he has also bred a 

 Tachina-fly from the larva. 



* Can. Entomologist, II, x^ageO. 

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