38 
127. Ridges of face bristly on at least the lower two-thirds (p. 120) Tachinopsis. 
Ridges bristly on less than the lowest third (p. 120) DcmoHcus. 
128. Lower front corner of the third antennal joint produced in the form of a sharp 
tooth (p. 115) Aoemyia. 
Lower front corner of the third antennal joint not produced in a tooth. 
Vibrissas on a level with the front edge of the oral margin. (p. 113) Masicera. 
Vibrissa* far above the level of front edge of oral margin.. (p. 81) Biomyia. 
129. Eyes bare or with indistinct short, sparse hairs 133. 
Eyes distinctly hairy, antenna' reaching at least to lowest fourth of the 
face 130. 
130. Frontal bristles not descending below base; of second antennal joint; abdomen 
largely or wholly opaque gray poll i nose 131. 
Frontal bristles descending below middle of second antennal joint 132. 
131. Cheeks nearly as broad as the eye height (p. 64) Hyalurgns. 
Cheeks less than one-third as broad as the eye height (p. 61) Mac<iuartia. 
132. Body shining, destitute of pollen (p. 61) Polidea. 
Body partly or wholly opaque pollinose (p. 63) Didyma. 
133. Frontal vitta opaque, abdomen of four segments besides the very short basal 
one 131. 
Frontal vitta shining black, abdomen of only three segments besides the very 
short basal one (p. 73) Hemyda. 
134. Apical cell op< n, or with a petiole less than one-half as long as the hind cross- 
vein 137. 
Apical cell closed, the petiole almost as long as the hind crossvein 135. 
Abdomen sub: -ylindi i< al. nearly twice as long as wide, the second and third 
segments destitute of discal macrochsetae 136. 
Abdomen siihhemispherical. only slightly longer than broad, the second and 
third segments bearing discal macrochsetae (p. 70) Hyalomyodes. 
136. The ocellar bristles curving backward, small crossvein before the tip of the 
tirst vein (p. 68) Leucostoma. 
The ocellar bristles directed obliquely forward, small crossvein far beyond the 
tip of the first vein . (p. 69) Sciasma. 
137. Palpi subcylindrical, less than one-half as wide as the proboscis 138. 
Palpi flattened and unusually dilated, wider than the proboscis, penultimate 
joint of arista almost one-half as long as the last one (p. 57) Lispidea. 
138. Penultimate joint of arista over 1 wice as long as broad 139. 
Penultimate joint of arista at most only slightly longer than broad 142. 
139. Third vein at most bearing four bristles near its base 140. 
Third vein bristly almost to the small crossvein (p. 57) Thryptoccra. 
140. Arista slender on apical half of the last joint, third antennal joint entire in 
both sexes 111. 
Arista thickened to the apex, third antennal joint in the male divided length- 
wise into two parts ( p. 55) Schizotachina. 
141. Hind crossvein nearer to bend of fourth vein than to the small. (p. 55) Medina. 
Hind crossvein nearer to the small than to bend of fourth vein . (p. 55) Claiuticella, 
112. Sides efface at narrowest part at most one-third as wide as the median depres- 
sion, fourth vein entire 143. 
Sides of face one-half as wide as the median depression, fourth vein obliterated 
beyond the bend (p. 66) Bacodineura. 
143. Head at the vibrissa' noticeably shorter than at base of antennas 144. 
Head at the vibrissas as long as at base of antenna' 149. 
144. Horizontal diameter of the occiput above the neck less than one-half as long as 
that of the eye 145. 
Horizontal diameter of occiput above the neck as long as that of the eye, antennae 
reaching at least to lowest fifth of the face, vibrissas on a level with front 
edge of the oral margin (p. 65) Pelatachina. 
