RILEY NOTES ON NORTH AMERICAN MICROGASTERS. 313 



to transform, tliough some transform while lying on the surface."* 

 The silk is spread out upon the leaf about the caterpillar in an 

 inegular mass and no definite cocoons are visible. 



Apanteles PALEACRiT.E, n. sp. — Length 2i-3 mm. c??. Black; la- 

 brum, mandibles and antennae piceous, palpi whitish; legs red, anterior 

 coxa- piceous, posterior black, the posterior femora at tip, the apical half 

 of posterior tibiie and the posterior tarsi excepting the base of the joints, 

 black; wings hyaline, tegulse piceous, nervures testaceous, stigma darker; 

 lateral edges of the basal joints of the abdomen and the sides of these 

 joints beneath piceous or testaceous. Mesothorax densely punctured ; meta- 

 thorax sparsely punctured, without median ridge. First and second joints 

 of the abdomen rugose, the second joint with two distinct oblique grooves 

 (in the Canadian specimens the middle of the joints almost smooth) ; 

 remaining joints smooth. Ovipositor concealed. The radial vein arises 

 beyond the middle of stigma and passes into the basal vein of the areolet 

 quite evenly. 



Described from 3 $ s, i d", bred from the larva of Paleacrita 

 vernata found at Villa Ridge, Southern Illinois, the flies appear- 

 ing May 20th, and from 2 $s bred from Canker-worm larvae, 

 probably of the same species, received from Mr. J. Pettit, Canada 

 West. The greenish-white cocoons are spun singly on the under 

 side of a leaf. The flies difler from congregatus in the oblique 

 grooves on second joint of abdomen and in the dark posterior 

 tibiae and tarsi. 



LIST OF NORTH AMERICAN SPECIES HERETOFORE DESCRIBED. 



All the species following have been described under the generic 

 name Microgaster, that term being employed indiscriminately 

 for the three genera treated of in this article, and it may be noted 

 that all specific names should have been feminine. The original 

 spelling is here quoted because the names of such species as may 

 be referred to Microplitis or Apanteles will retain or take a 

 masculine form. It may ultimately be found that mellipes Say, 

 bistigmata Say, and possibly some of the other described species, 

 do not really belong among the Microgasters. 



UNITED STATES. 



calliptcra Say, Bost. Journ. Nat. Hist., i. 264 (1S36). Probably a 



\^Microplitis. 



* Second Report on the Insects of Missouri, 1870, p. 120. 



