1896.] NATURAL SCIENCES OF PHILADELPHIA. 59 



C. (1). Larger, clypeus higher, siipraclypeal mark absent, lateral 



marks notched within, . . . odomaculata 9 . 



(2), Smaller, clypeus lower, siipraclypeal mark present, lateral 



marks not notched within. . . ^nevadensis 9 . 



Species found east of the 95th meridian. 

 10. Perdita obscurata Cr., Tr. Am. Ent. Soc, 1878, p. 70. cf ? (Hab., Georgia). 



One male and one female were found by Morrison. I have made 

 the following description from the female ; the student will observe 

 that in some points it disagrees with that of Cresson, notwithstand- 

 ing that it is from the same specimen. 



$ . — Head and thorax dark bluish -green. Clypeus broad, not 

 much attenuate at sides, reaching base of mandibles. Face-mark- 

 ings pale yellow, lateral marks very narrow, inversely club-shaped, 

 reaching as far as level of insertion of antennae. Clypeus without 

 marks, except a very distinct central one, shaped like an inverted 

 egg-cup with the egg in it, the base at posterior clypeal border, the 

 apex not reaching anterior border of clypeus. Mandibles except 

 tips pale yellow. Mesothorax shiny. Tubercles rather pale brown- 

 ish. Hind margin of prothorax with two small yellow spots. Wings 

 hyaline, stigma very large, pale yellowish, veins colorless. Mar- 

 ginal cell with the substigmatal portion a little longer than the post- 

 stigmatal. First submarginal very long, longer than marginal. 

 Second submarginal short, suboval and high, narrowed about one- 

 half to marginal. On one side there is a small petiolate submarginal 

 •cell between normal 1st and 2d submarginals, it receives the first 

 recurrent nervure, and is approximately an equilateral triangle. 

 Third discoidal distinct. The broadly interrupted narrow fascise 

 on abdomen are not obscure or suffused, but clean-cut and distinct. 

 It differs from the 9 of affinis by the lateral face-marks being 

 pointed above, the clypeus dark marked with light, the mesothorax 

 shiny, the nervures colorless, and the abdominal marks yellowish. 



The $ I have not seen ; Mr. Fox has kindly sent me a sketch of 

 the face-markings, showing the face entirely yellow below the level 

 of the antennae, the yellow not extending upward at all in the 

 median line, but obliquely extending upward at the sides from the 

 antennal socket to the orbital margin, where it ends at an angle of 

 about 50°. The cheeks, Mr. Fox informs me, are not armed. 



Mr. Charles Robertson tells me that at Orlando, Florida, on March 

 16th, he captured a $ obscurata on lowers of Sydrocotyle icmbellata. 



