183] HEAD OF DIPTERA—PETERSOX 13 



Diopsiclae.— Sphyracephala bicornis (Fig. 52. 94, 190, 293, 338, 450, 



451, and 585). 

 Ephydridae.— Ochthera mantis (Fig. 56, 101, 187, 237, 297, 336, 



444, 445, 483, and 574—577), Paraliinna appendiculata, and 



Parydra bituberculata. 

 Oscinidae.— Chloropisca glabra (Fig. 51, 132, 189, 306, 345, 430, 431, 



555, and 556), Siphonella abdoniinalis, and Hippelates flavipes. 

 Drosopliilidae. — Drosopliila ampelophila (Fig. 45, 125, 172, 238, 291, 



343, 454,455, 563, and 564). 

 Geomyzidae.— Chyromya concolor (Fig. 50, 122, 179, 233, 299, 333, 



411, 412, 568, and 569). 

 Agromyzidae.— Desmometopa latipes (Fig. 47, 129, 185, 228, 303, 



330, 404, 405, 578, and 579). 



Suborder Eproboseidea 



Hippoboscidae.— Olfersia ardeae (Fig. 57, 139, 198, 249, 358, 488, 

 and 606), and Melophagus ovinus. 



Orthoptera 



Periplaneta orientalis (Fig. 514). 

 IMelanoplus differentialis (Fig. 515). 

 Grj'llus pennsylvanicus (Fig. 516). 



Hypothetical and typical figures (Fig. 1, 73, 140, 141, 199h, 256h, 

 257, 362, 363, and 493). 



FIXED PARTS OF THE HEAD 



A hypothetical head-capsule of Diptera (Fig. 1) has a dorso-ventral 

 extension. The epicranial suture (e. s) is present on the meson, and 

 extends from the occipital foramen (o. f ) to a point on the cephalic 

 aspect ventrad of the antennae. At this point it bifurcates and the two 

 arms continue to the invaginations of the anterior arms of the tentorium 

 (i. a), which are situated at the dorso-lateral angles of the clypeus (c). 

 The three unpaired sclerites included within, or ventrad of, the fork of 

 the epicranial suture are the front (fr), clypeus (c), and labnim (1). 

 The fronto-elypeal suture is represented by a dotted line in the figure. 

 The vertex (v) includes all of the dorsal and cephalic aspects of the 

 epicranium except the front (fr), while the genae (ge) are the regions 

 of the vertex ventrad and mesad of the compound ej'es. Two large 

 compound eyes (c.e) cover the lateral portions of the cephalic aspect. 

 Three ocelli (oc) are situated on the vertex. The occiput (occ) and 

 postgenae (po) constitute the caudal aspect of the head-capsule. 



