294 
Hominoxious Arthropods 
ii. Proboscis extending beyond the palpi. 
j. Wing with cell M3 closed. Tropic America . 
. ( = Diclisa ) Scione Wlk. 
jj. Cell M3 open; ocelli present or absent. Two or three 
eastern species; many south and west. . Pangonia Rdi. 
ff. Third segment of the antenna with five divisions; ocelli present, 
g. First and second segments of the antenna short, the second only 
half as long as the first, three western species. . . .Silvius Rdi. 
gg. First and second segments of the antenna long, the second 
distinctly over half as long as the first. Deer flies. Many 
species, widely distributed . Chrysops Meig. 
ee. Hind tibia without spurs; ocelli absent. 
f. Third segment of antenna with four divisions, no tooth or angula¬ 
tion; wings marked with rings and circles of darker coloring; 
front of the female very wide. Widely distributed. H. ameri- 
cana, H. punctulata .Hasmatopota Meig. 
ff. Third segment of the antenna with five divisions (fig. 161b). 
g. Third segment of the antenna not furnished with a tooth or 
distinct angular projection. 
h. Body covered with metallic scales; front of female of normal 
width; front and middle tibiae greatly dilated. L. 
lepidota . Lepidoselaga Macq. 
hh. Body without metallic scales; antennae not very long, the 
third segment not cylindrical, not situated on a projecting 
tubercle; front of the female narrow. South. D. 
ferrugatus . ( =Diabasis) Diachlorus 0 . S. 
gg. Third segment of the antenna furnished with a tooth or a 
distinct angular projection. 
h. Hind tibiae ciliate with long hairs. S. W. and tropics. 
. Snowiella and Stibasoma. 
hh. Hind tibiae not ciliate. 
i. Species of slender build, usually with a banded thorax and 
abdomen; third segment of the antenna slender, the 
basal prominence long; wings mostly with brownish 
markings. Tropic America . Dichelacera Macq. 
ii. Species of a stouter build; third segment of the antenna 
stout, its basal process short (fig. 161b). Many species, 
widely distributed.Tabanus L. 
dd. With another group of characters. 
e. Squamae small, antennae variable, thinly pilose or nearly bare species, 
without distinct bristles; wing veins not crowded anteriorly, R4 and 
R5 both present, basal cells large; middle tibiae at least with spurs 
. LEPTIDjE 
f. Flagellum of the antenna more or less elongated, composed of 
numerous more or less distinct divisions . 
. Xylophagin/E and Arthkoceratin.e. 
ff. Antennae short, third segment simple, with arista or style; face 
small, proboscis short .. Leptin.® 
