DIPTERA. 337 



1. Femora largely black 2. 



Femora yellow or but little infuscated 5. 



2. First part of costa greatly thickened in male, perceptibly 



in female Paraclius albonotatus, Loew. 



Costa not noticeably thickened 3. 



3. Fore femora yellow Paraclius femoratus, sp. n. 



Fore femora black 4. 



4. Tibiae of male wholly black Pelastoneurus hamatus, sp. n. 



Tibiae of male largely yellow Paraclius humeralis, sp. n. 



5. Wings with numerous brown spots Pelastoneurus punctipennis , Say. 



Wings not spotted, or with one or two spots on the veins . 6. 



Wings of male with a rounded apical brown spot . . . Pelastoneurus bigeminatus, sp. n. 



6. Inner claw of male fore tarsus enlarged and bent backward 



to form a small grasping-organ Pelastoneurus unguiculatus, Aldr. 



Claw not specially modified ' '• 



7. Cilia of inferior orbit black 8. 



Cilia of inferior orbit white 9. 



8. Middle and hind coxae yellow Sarcionus flavicoxa, sp. n. 



Middle and hind coxae mainly black Pelastoneurus lugubris, Loew. 



9. Face of male with a brown stripe in the middle; sides 



greyish-white Pelastoneurus cognatus, Loew. 



Face of male not so marked • • 10- 



10. Fore coxae infuscated beyond the middle Pelastoneurus vagans, Loew. 



Fore coxae not or scarcely infuscated 11- 



11. Dorsum with a distinct median stripe Sarcionus lineatus, Aldr. 



Dorsum without stripe 12. 



12. Upper part of face brilliant green Pelastoneurus argentiferus, Aldr. 



Upper part of face not green Paraclius venustus, sp. n. 



1. Pelastoneurus unguiculatus. 



Pcecilobothrus unguiculatus, Aldrich, Trans. Ent. Soc. Lond. 1896, p. 310, 1. 11. fig. 101, t. 12. fig. 116'. 

 Hab. Mexico, Atoyac in Vera Cruz (H. II. Smith).— Antilles, St. Vincent l . 



Eleven specimens, including both sexes. One of the most difficult species to locate 

 generically. The face is narrow for Pelastoneurus, but too wide for PoecUobotkrm, 

 while the plumose arista throws it out of Paraclius. 



2. Pelastoneurus lugubris. 



Pelastoneurus lugubris, Loew, Neue Beitr. viii. p. 38 l ; Mon. N. A. Dipt. ii. p. 105 \ 



Hab. Noeth Amekica, Trenton Falls, New York 1 2 .— Mexico, Vera Cruz (H. H. 

 Smith). 



Five specimens. 

 biol. cente.-amee., Dipt., December 1901. 2 x 



