AMERICAN HYMENOPTERA. 129 



Pisonopsis birkmanni n. sp. 



Female. — -Length 6 mm.; length of anterior wing 4 mm. Robust. 

 Clypeus punctured like the front; produced in the middle into a 

 shining, acute triangular process. Front and vertex rather closely- 

 punctured with distinct punctures; cheeks and occiput shining, punc- 

 tured with smaller punctures. The distance between the eyes at the 

 vertex very little if any less than the distance at the clypeus; a little 

 below the middle distinctly, though not strongly so, emarginate. Third 

 and fourth joints of the antennae equal. Dorsulum and scutellum 

 punctured with rather large, well separated punctures, the punctures 

 about uniform throughout; suture between the scutellum and dosulum 

 strong; scutellum not impressed; mesopleuras punctured like the dor- 

 sulum in the middle, around the sides more densely so. Metanotum 

 with a depressed triangular area, which is transversely striated, some- 

 what obliquely so anteriorly. Rest of the metathorax is punctured 

 about as the front is, at some angles it appears finely striated. Pos- 

 terior face of the metathorax with a deep fovea at the upper middle. 

 Except the spurs the legs are unarmed. Longer spur of hind tibiae 

 almost as long as the basal joint of the hind tarsi. Tranv. med. n. 

 almost interstitial with the basal nervure, but placed just a little 

 before it; radial cell rounded at the apex, not appendiculate; third 

 cubital cell as wide on the rad. n. as on the cub. n. First abdominal 

 segment emarginate basally; first three abdominal segments constricted 

 apically, the third not so strongly so as the two preceeding; abdomen 

 shining, sparsely punctured. Pygidium apparently wanting 



Black, except the posterior margin of the tubercles, which are white. 

 Clypeus, cheeks, parts of the thorax, and sides of the first three abdom- 

 inal segments with sparse, white hair. Wings dusky hyaline; venation 

 dark brown. 



Habitat. — Lee Co., Texas, June, 1908 (G. Birkmann). 



This species has its nearest ally in P. triangularis Ashm. 

 (Colo.), but it may be separated from that species by having 

 the metathorax punctured instead of rugose, and not having 

 the ventral segments 2-5 testaceous along the apical margin. 



It is quite distinct from P. clypeata Fox (Nevada), easily 

 known by the different sculpture and the black abdomen. 



The last abdominal segment is slightly retracted, but as 

 far as I can see, there is no pygidium. In this it departs from 

 the genus. The eyes are not strongly emarginate and at first 

 one might take it for a Plenoculus , but there is no appendicula- 

 tion to the raidal cell, the eyes do not converge towards the 

 vertex and the pronotum reaches almost to the level of the 

 dorsulum. There are also other things which will exclude it 

 from Plenoculus. 



TRANS. AM. ENT. SOC, XXXV. (17) MARCH, 1909. 



