I20 OHIO BIOLOGICAL SURVEY 



EXPLANATION OF PLATE X. 



Fig. 2or Microdon juscipennis, scutellum, showing the ornamental spines. 



Fig. 202 Microdon tristis, scutellum, showing the ornamental spines. 



Fig. 203 Chalcomyia aerea, female, large, sub-rectangular scutellum. 



Fig. 204 Microdon fuscipennis, antenna. 



Fig. 205 Microdon tristis, antenna. 



Fig. 206 Microdon fuscipennis, male, hind tarsus. 



Fig. 207 Microdon tristis, male, hind tarsus. 



Fig. 208 Pipiza pisticoides, female, face from the side. 



Fig. 209 Chrysogaster nigripes, female, face from the side. 



Fig. 210 Chrysogaster nitida, female, head from in front with antennae removed, 

 showing the wrinkling of front and face and the color markings on the 

 eyes. 



Fig. 211 Chrysogaster pictipennis, female, wing. 



Fig. 212 Chalcomyia aerea, hind leg showing distinctly thickened femur. 



Fig. 213 Mesogramma geminata, female, vertex and part of the front, showing 

 ocelli remote from the vertex. 



Fig. 214 Platychirus hyperboreus, male, front tibia and tarsus. 



Fig. 215 Platychirus peltatus, male, front femur, tibia and tarsus. 



Fig. 216 Platychirus quadratus, male, front tibia and tarsus. 



Fig. 217 Baccha clavata, male, distinctly clubbed abdomen. 



Fig. 218 Helophilus similis, male, dorsal view of head with antennae removed, 

 showing shape of front in a dichoptic male. 



Fig 219 Helophilus similis, female, dorsal view of head. 



Fig. 220 Chilosia rvillistonii, female, antero-lateral view of a part of the head to 

 show the orbital groove (b); a, facial orbit. 



Fig. 221 Eristalis flavipes, female, antenna with a pubescent arista. 



Fig. 222 Volucella evecta, female, antenna with a plumose arista. 



Fig. 223 Xanthogramma felix, female, lateral view of head showing the face re- 

 ceding below. 



Fig. 224 Ocyptamus fuscipennis, female, antero-dorsal view of head showing the 

 long front much narrowed above. 



Fig. 225 Rleiapioidus villosns, lateral view of antenna, showing the peculiar shape 

 of the third joint. 



Fig. 226 Dorsal view of the same. 



Fig. 227 Rhingia nasica, lateral view of the head showing the long porrect snout. 



Fig. 228 Spilomyia hamifera, female, hind femur and tibia. 



Fig. 229 Tropidia quadrata, female, antero-dorsal view of part of the head showing 

 the carinate protuberant face, antennae removed; a, the carina or long- 

 itudinal ridge. 



Fig. 230 IMicrodon fuscipennis, wing showing venation; the color pattern is not 

 shown. 



