142 TRANS. ST. LOUIS ACAD. SCIENCE. 



3. The 4 front legs are white, generally immaculate, but occasionally with 

 the femora tinged with rufous. In the hind legs both trochanters are 

 white; the femora have a distinct white knee preceded by a black annu- 

 lus; and the tibia; on their second J have only a short lateral black vitta. 



4. The wings are hyaline; veins black, radius whitish; stigma black, ba- 

 sally whitish. Radial area short, with a posterior angle of only iio" or 

 115°. Length cT •17--24 inch. Front wing rj!*. 15-- 18 inch. 



Four % ; $ unknown to me. Three % were taken Apr. 18 in 

 the window of a dwelling-house infested by carpet-moths {Tifiea 

 tapetzella^ Lin.), on which they had probably been preying. 

 Known easily from my ^ oiinquisitor by the oblong ist abdom- 

 inal joint, and from that % and all my other Pimpla ^ ? by the 

 short radial area and the elongate intermediate joints of the abdo- 

 men. The sides of the abdomen are parallel, and joint 2 is i 

 longer than wide, the succeeding joints each gradually shorter 

 till joint 5 is square. Hence, strictly speaking, it does not belong 

 to Pimpla as defined by authors, and it might be referred to 

 Ephialtes with almost equal propriety, though the tarsal claws 

 are simple. .1 refer it provisionally to Pimpla^ partly on account 

 of its having no tooth on the tarsal claws, partly on account of 

 its coloration, and especially that of its legs, agreeing so closely 

 with that of the species which precede it and being quite differ- 

 ent from that of any Ephialtes known to me, and partly on 

 account of the short radial area which is utterly abhorrent from 

 Ephialtes. For in most Ephialtes and in Pimpla melanocC' 

 phala the radial area is very elongate, while in all my other 

 Pimpla it is of medium length, its posterior angle being about a 

 quadrant and a half, or 135°. Indagatrix is in reality one of 

 those aberrant species which so often perplex and annoy syste- 

 matists and delight the souls of Lamarck and Darwin. 



Section 3. — AreoUt triangular. {Hind tibia as in Section 2, 



ttt-) 



Pimpla lllYestigatrLx, n. sp. — $ . — Differs from the normal inquisitor $ 

 only as follows : — i. The antennae are full \ as long as the body. 2. The 

 quadrangular white spot before the tegula is always prolonged in an acute 

 white line which generally reaches halfway to the tip of the humeral su- 

 ture. 3. The abdomen is much more coarsely, and although closely, yet 

 not confluently, punctate. 4. The ovipositor is bright rufous, sometimes 

 so pale as to be almost ochreous. 5. In the front legs both trochanters 

 are always white, but in the middle legs the 2d trochanter is never so. 

 6. The areolet is subpetiolated and triangular, the 2d recurrent vein 



