402 



ending considerably below the extreme apex of the wing; small cross vein straight 

 and nearly ou a line with the second vein ; anterior fork of the third vein (the true 

 fifth vein, since the third and fourth are absent), nearly twice as long as the posterior 

 branch. 



Female. — Same as the <? with these exceptions : AntenuiP only one-fourth longer 

 than the body, joints 3 to 14 subcyliudrical, slightly constricted at the middle, con- 

 siderably narrowed at the apex of each, this portion of the sixth joint equaling 

 one-half of the thickened part of the joint, but on the foui'teenth joint it is only one- 

 eighth as long as the thickened part; each joint from 3 to 14 bears on the thickened 

 jiortion a basal and an apical whorl of rather long bristly hairs. 



Leugtii, 1 to l.S™"". Four iriales and iifteen females. 



AN INJURIOUS PARASITE. 



By L. O. Howard. 



Tig. i^.—Lcucodesmia typica : female, Txith. head of male below at right— greatly enlarged (original). 



It is a pity tliat the energetic parasites of tlie fauaily Olialcididtv do 

 not confiue tlieir attacks to iujurioiis insects. The great majority of 

 the species are parasitic upon injurious forms. Many, however, lay 

 their eggs in beneficial insects, and thus become injurious species them- 

 selves. It is an example of this class which we shall describe in this 

 note. 



In 1879 Prof. J. H. Coinstock called attention for the first time to 

 the good which was occasionally done by the i)redaceous larva of a 

 lepidopterous insect, which he described in the North American Ento- 

 mologist as Dalcruma coccidirora, by feeding upon our larger scale 

 insects. The first specimens observed by Comstock were feeding upon 

 the cottony maple scale {Pidvinaria innumerahilis) at Washington. So 



