NATURAL SCIENCES OF PHILADELPHIA. 107 



Rather large, slender ; scutellmn rather flat, white, sides abrupt ; 

 mesothorax opaque, with white spot on each side over tegula^ ; 

 metathorax with long acute spines, and with a broad black T 



mark above 65. rixosus. 



Body metallic blue-green ; legs ferruginous ; antenna black, with white 

 annulus ; scutellum flat above with white spot, carinate la- 

 terally, sides abrupt 64. virescens. 



Body black ; apex of abdomen and legs, except apex of posterior femora 

 and tibia3, yellow ; antenn.ie black with white annulus ; scu- 

 tellum flat in 9 , convex in % 1. couicus. 



Body dull-black, opaque ; orbits, scutellum, two stripes on metathorax, 

 and narrow band on two or three basal segments of abdomen, 

 white ; costal margin of anterior Avings fuscous. 



17. opaculus. 

 Body deep black ; abdomen long and subcylindrical ; with apical margin 



of first and second segments white 18. junceus. 



Body black, marked with white or yellowish ; abdomen with white or 

 yellow and black bands on all the segments: 

 Metathorax without prominent lateral tubercles : 

 Mesothorax with a white or yellow discal spot : 



Line on posterior femora above and their tibise except tips, black, 



their tarsi yellow 37. Cholula. 



Apex of posterior femora and tibiae, and their tarsi black. 



53. amecus. 

 Mesothorax with discal lines abbreviated : 

 Abdomen long, parallel, coarsely sculptured, gastrocoeli large and 



very deep 36. prolixus. 



Abdomen shorter, finely and densely punctured, gastrocoeli small, 

 deep ; pleura yellow, with a longitudinal black stripe. 



19. zapotecus. 

 Abdomen polished, with second segment finely and densely punc- 

 tured ; gastrocoeli small, punctiform ; thorax with three large 



lateral white spots 23. tepanecus. 



Abdomen entirely polished, impunctured ; gastrocoeli subobsolete ; 

 thorax with two large lateral white marks, the anterior one 



larger and oblique 31. zacatecus. 



Abdomen long, rather slender, granulated, gastrocoeli large, deep : 



Posterior thighs black above and within 40. Toluca. 



Posterior thighs entirely honey-yellow 41. Chalco. 



Abdomen elongate, depressed ; metathorax except basal suture or 



a basal median black spot, yellow 53. paraudus. 



Mesothorax with discal lines entire : 

 Metathorax with a central black stripe and slender lateral line. 



59. centrosu3. 



Metathorax with a central black stripe and a lateral sub-basal Mack 



spot 58. decorosus. 



