AMERICAN HYMENOPTERA. 295 



iceous, yellowish pubescence; tip of antennae hooked and acute ; meta- 

 thorax with a large yellow spot on each side at base; pleura and uieta- 

 thorax silvery; second segment of abdomen with a short, transverse, 

 sometimes uneven, line on each side, instead of a band as in 9 5 tte- 

 neath, the second segment has a large reniform mark at tip, sometimes 

 with a median fuscous spot; otherwise as in 9 • Length G lines. 

 Two specimens. (Coll. Am. Ent. Soc. and Dr. J. Gundlach, No. 444.) 



Agapostemon obscurata, n. sp. 



$. — Differs fvom /emoralis % only by the head and thorax being- 

 opaque black, with a more or less distinct purplish tinge, especially ob- 

 vious on the face; the tip of clypeus and labrum are yellow, as in /em- 

 oralis. Length 4 — 4' lines. 



Eight specimens. (Coll. Am. Ent. Soc. and Dr. J. Gundlach, No. 

 261). I at first supposed this to be a variety of fcmoralis (see Proc. 

 Ent. Soc. Phil, iv, p. 171), but now think, with Dr. Gundlach, that it 

 is a distinct species. 

 Megacilissa? nigrescens, n. sp. 



% . — Black; eyes large, almost meeting in the vertex, brown ; cheeks, 

 vertex and face, clothed with yellowish-white pubescence, slightly mix- 

 ed with black; behind the ocelli the pubescence is black ; third joint 

 of antennae long and slender, knobbed at the apex, sutures of remain- 

 ing joints indistinctly defined, and palish beneath, the extreme tip slight- 

 ly fulvous ; thorax covered with a very dense, short, brown-black pu- 

 bescence, a transverse band on the anterior margin, another between 

 the wings, a stripe over the tegul^e, a mark on each side of the breast, 

 behind the anterior femora, of whitish pubescence ; metathorax with 

 longer brown-black pubescence, and mixed with white posteriorly; teg- 

 ulse piceous ; wings yellowish-hyaline, the neuration same as given by 

 Smith (^Brit. Mus. Cat. Ili/m. I, pi. iv, fig. 21) as that of Mrgacilissa ; 

 legs slender, brown, the femora reddish-brown behind, the pubescence 

 short and pale brownish, the coxas and base of femora with long dark 

 pubescence, mixed with whitish; posterior legs slender, their tibiae 

 slightly curved downward; first joint of tarsi flat and as long as the 

 remaining joints together; claws cleft; abdomen shaped much as in 

 Apis, the first, fifth and following segments with long pubescence, that 

 on the former mostly white, on the latter blackish; remaining segments 

 almost nude, having a very short black pubescence, brownish when view- 

 ed in certain lights, their apical margins with a narrow fascia of pure 

 white pubescence ; venter flattened, piceous, paler at base, thinly pu- 

 bescent. Length 7 lines. 



One specimen. (Coll. Dr. J. Gundlach, No. 293.) 



