NATURAL ENEMIES. 66 
Described from many male and female specimens, only three of the latter being 
winged. All bred from final larva of the Hessian fly collected at Cadet, Mo., by 
J. G. Barlow, and issuing through tin; coarctate larva shell. 
Distinguished from other described species by tin- contrasting antenna? in the - 
and by the ovate abdomen which, when fresh, has no flattened dorsal surface. 
This species is probably, next to destructor, the most important of the 
Hessian fly parasites. Indeed, Dr. Riley has stated that t he relative 
abundance of this and the preceding species is probably a question of 
latitude or location, and this species has been bred much more com- 
monly than destructor from infested wheat from Missouri. The winged 
and wingless individuals are considered as certainly belonging to tin- 
same species, and the proportion of winged to wingless individuals is 
said to vary at different seasons of the year. '-Thus, from a lot of 
puparia of the Hessian fly, received in the summer of 1883 from Mis- 
souri, there issued 31 wingless males, 28 wingless females, and 3 winged 
females. Of these about one-third issued from the straw in August. 
1883, and the rest, including all the winged individuals, hibernated in 
the straw and issued in April and May, 18S4."' 
From this it would appear that we may have much the same retarda- 
tion of development in the parasite as in the host, and that the appear- 
ance of adults in autumn or in the following spring may be a matter of 
conditions. 
Pteromalus pallipes Forbes. 
A short, thick species, with the head broader than the thorax, the abdomen ovate 
and obtuse. Head and thorax bronzed black, thickly set everywhere with punctures 
of medium size. The occiput and the dorsum of the thorax with a lew scattered 
appressed hairs. The front of the head is vertically grooved for the long, first joints 
of the antenna'. Eyes pale red, month-parts brown. The antennse are about as 
long as the head and the thorax, thirteen jointed, the first joint pale j ellow, second 
joint dusky, the remaining joints black. The first joint is about equal in length to 
the lour following, the third short, that and the fourth together shorter than the 
second and about equal to the fifth, the joints widening from the first to the fifth 
(except the third, which is not wider than the second), the following joints, to the 
eleventh, of about equal diameter, thence tape) ing rapidly, the last three not being 
clearly distinguished. The first joint is nearly smooth, the second somewhat hairy, 
all the others black pubescent, each with a transverse ring of long appressed yellow 
bristles. The mesoscutellum is broadly rounded behind, the sides with an irregular 
excavation, the met ascutellum with an elevated margin and an evident median 
carina. The sides of the mctathorax are densely clothed with long black hairs. 
Wings transparent, veins dusky yellowish, the post-costal and stigmal of equal 
length, about two-thirds as long as the costal. Wing membrane sparsely pubescent, 
the veins with a row of still', erect black hairs. Patagia dusky yellowish. 
The legs are pale yellow throughout, except t he coxa-, which are of t he body color. 
The abdomen is smooth and shining, except the under sides of the three posterior 
segments, which are pubescent. It is black above and piceous beneath, the i 
of the segments being somewhat tinged with brown. 
Length, 2.o nun.; head, 0.95 mm. wide; thorax, 0.7 by 1.06 mm. Long; antennse, 
1.23 mm. ; wing, 1 .!» mm. 
6086— No, 10 :.S 
