1916.] NATURAL SCIENCES OF PHILADELPHIA. 375 



6. Very small, less than ."> mm. long, tarsi yellowish farticornis Ckll. 

 Larger, at least over 5 mm. long 7. 



7. Tarsi black spenceri Ckll. 



Tarsi red or yellow 8. 



8. Stigma ferruginous; head broad and massive....pachycephalus Ckll. 

 Stigma fuscous 9. 



9. Mesothorax shining dolichocerus Ckll. 



Mesothorax dull hcematopus Ckll. 



10. Small, hardly 5.5 mm. long semipolitus expulsus Ckll. 



Larger .11. 



11. Disc of mesothorax with scattered punctures of different size, 



supralucens Ckll. 

 Disc of mesothorax well punctured, the punctures uniform 12. 



12. Fourth abdominal segment, except broad apical margin, densely 



covered with pale felt-like hair lanariellus Ckll 



Fourth segment not so 13. 



13. Hind margins of abdominal segments reddened; area of meta- 



thorax with irregular sculpture pulvitedus Ckll. 



Hind margins of abdominal segments black; area of metathorax 

 with fine definite longitudinal plicse 1-4. 



14. Stigma ferruginous; area of metathorax shorter confusi llus Ckll. 



Stigma piceous; area of metathorax longer imitans Ckll. 



