208 NEW YORK STATE MUSEUM 
distally, joining the margin at the apex of the wing; fifth vein sim- — 
ple, obsolete distally. Coxae, femora and tibiae fuscous yellowish, 
the tarsi tinged with red; claws rather long, evenly curved, simple, 
the pulvilli about half the length of the claws. Genitalia; basal 
clasp segment short, stout, obliquely truncate apically; terminal 
clasp segment short, stout, swollen subapically and with a heavy, 
chitinous spur at the internal distal angle; dorsal plate apparently 
short, triangularly emarginate, the lobes broadly rounded and 
sparsely setose; ventral plate apparently moderately long, stout, 
broadly rounded and sparsely setose apically; style short, stout, 
narrowly rounded distally. 
Life history. Reproduction by pedogenesis occurs in the fall and 
early spring, and under certain conditions apparently throughout 
warm weather, though adults are usually produced from the latter | 
part of May to August. Under favorable conditions it appears 
probable that pedogenesis may continue indefinitely. A larval gen- 
eration occupies about 3 to 3% weeks, much depending upon moist- 
ure, food and temperature. The transformations to the adult are 
preceded by the development of a distinct breastbone, this usually 
occurring in early May. The change is soon followed by the ap- 
pearance of the prepupa, characterized by a marked swelling and 
transparent condition of the anterior body segments of the larva, 
and in 2 or 3 days by the development of the pupa, a stage lasting 
about 6 days. The small midges appear in immense numbers during 
the late morning hours, namely from about 9 a. m. until noon, 
swarming over the sides of the jar and behaving much like minute 
ants. There is comparatively little tendency to take wing. The de- 
velopment of adults may continue for several days and the midges 
may appear in smaller numbers for a period of several weeks. The 
large eggs, well formed in the abdomen of recently transformed 
females, are presumably deposited shortly and another succession 
of larval generations begun. 
Natural enemies. Miastor is commonly preyed upon by the pink- 
ish larvae of Lestodiplosis, and it is probable that Itonida pug- 
ionis Felt has similar habits. The larger predaceous maggots of 
Lonchaea polita Loew and a species of Medetrus were 
commonly found in the vicinity of Miastor colonies and were not 
infrequently the only available evidence of the earlier presence of 
midge larvae. Pseudotephritis vau Say was repeatedly 
reared from bark infested by Miastor larvae. In some instances the 
Pseudotephritis larvae occurred in clusters. These larvae may be 
predaceous enemies of the smaller Miastors. 
