430 
THE STUDY OF INSECTS. 
long (Fig. 502). This family includes the larger members 
of that series of flies in which the antennae are thread-like; 
but it also includes some species that are not larger than 
certain mosquitoes. The most distinctive feature of crane- 
flies is the presence of a transverse V-shaped suture on 
the dorsal side of the mesothorax (Fig. 503). 
Fig. 502.—A crane-fly. 
Fig. 503.—Tho¬ 
rax of a crane- 
fly showing 
the V-shaped 
suture. 
The wings are long and narrow. In a few genera vein 
III is five-branched, and the branches separate near the 
middle of the wing (Fig. 504); but usually the number of 
11 
Fig. 504. —Wing of Proloplasa Jitchii. (After Osten Sacken.) 
branches is reduced to three or four; and those that remain 
distinct separate near the apex of the wing (Fig. 505). Cell 
V, is divided into two parts by a cross-vein ; the branches of 
vein VII like those of vein III separate near the distal end 
of the wing; and the margin of the wing is strengthened by 
an ambient vein. 
