1893.] NATURAL SCIENCES OF PHILADELPHIA. 473 



Third antennal joint but slightly curved, in length not quite 

 equalling the space between the eyes at the clypeus, fourth joint 



slightly longer than the fifth californicus. 



14— Thorax black, with golden pubescence; dorsulum finely punctured 



.. tt xense. 



Thorax in part rufous; dorsulum very strongly punctured 



colli II a a i. 



15 — Abdomen with base of second and third segments reddish fulvous 



Johnsonii. 



Abdomen entirely black 16 



16 — Front with a Y-shaped carina; clypeus rounded carinatus. 



Front with a short, longitudinal carina; clypeus with a slight 

 medial tooth .fast it/ i um. 



MALES. 



1 — Metanotum not trisuleate 2 



Metanotum trisuleate 13 



2 — Abdomen not banded with reddish 3 



Abdomen banded with reddish 8 



3 — Metanotum punctured or very finely striated 4 



Metanotum striated or rugose 5 



4 — Wings blue black; second ventral abdominal segment with a 



strong hook or spine neglectum. 



Wings with the anterior pair fuscous, posteriors hyaline except 



apex; thorax with pale pubescence albipilosum. 



Wings hyaline, their apical margins and the marginal cell fus- 

 cous; thorax with silvery pile excavatum. 



5 — Posterior trochanters armed with a spine clavatum. 



Posterior trochanters unarmed 6 



6 — Metanotum armed with two stout projections at apex; front with 



a strong projection .projection . 



Metanotum without any such projections 7 



7 — Apical antennal joint much shorter than the three preceding 



joints .frigidum. 



Apical joint of antenna? fully as long, if not longer than the three 



preceding joints united bidentatum. 



8 — Posterior trochanters unarmed 9 



Posterior trochanters armed with a spine 10 



9 — Metanotum punctate; base of second segment reddish 



rubrocinctum. 



Metanotum striated, with two strong projections at apex 



tridentatuiii. 



10 — Antennae entirely black 11 



Antenna? more or less reddish VI 



11 — Clypeus emarginate medially; legs black, the hind tarsi whitish 

 medially rufozonale. 



31 - 



