No. 22.] HYMENOPTERA OF CONNECTICUT. 47I 



ment shorter than third, the following segments subequal. Male : 

 length 1.8-2 mm.; differs from the female chiefly as follows: 

 abdomen oblong, sometimes with a yellowish spot at base, second 

 segment about half as long as the abdomen, third segment only 

 half as long as the first, fourth and fifth scarcely half as long 

 as the third. 



Bred from Chlamys plicata. 



Pteromalus Swederus. 

 °P. puparum Linnaeus. Scudder, Butterflies of New Eng- 

 land, Vol. iii, PI. 89, Figs, i, 2. 



Female: length 1.3-4 mm.; head a little broader than the 

 abdomen, transverse, greenish bronze, closely punctate, slightly 

 narrower behind the eyes, vertex emarginate in the middle, ocelli 

 equidistant from each other or nearly so, face rather flat, antennal 

 grooves inconspicuous, cheeks convex, slightly compressed, eyes 

 subovate, subconvex, clypeus emarginate at apex in the middle, 

 mandibles with four acute teeth, the apical one distinctly sinuate, 

 antennae thread-like, inserted in the middle of the face close to- 

 gether, brown or fuscous, scape, however, linear and yellow, 

 second joint oblong, third distinct, fourth a little larger than 

 third, fifth to tenth joints equal in width but subequal in 

 length, club in the form of an elongate cone ; thorax slightly con- 

 vex above, almost smooth, with adjoining umbilicate punctures, 

 metanotum punctate, without a median carina but with arcuate 

 lateral folds, spiracles suboval, and in the spiracular sutwre ; 

 wings hyaline, subcostal cell broad, marginal vein longer than 

 stigmal and a little shorter than post-stigmal ; coxae green, femora 

 fuscous bronze, tibiae occasionally concolorous; mesopleurae deli- 

 cately puncate; abdomen ovate, flat above, convex beneath, its 

 sides rounded, a little shorter than the thorax, considerably 

 broader, its first segment dark blue and hidden. Male: differs 

 from female chiefly in its thinner, more pilose antennae, oblong 

 abdomen, which is golden above, green head, which is broader 

 than the thorax, and femora and tibiae which are always yellow. 



This species is most beneficial, inasmuch as it may destroy as 

 many as ninety per cent, of the injurious common cabbage worm 

 or cabbage butterfly, (Pieris) Pontia rapes. It is on record as 

 having been bred also from the following: {Vanessa) Euvanessa 



