IOWA ACADEMY OF SCIENCES. 
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costa, which it joins abont two-thirds the distance from pteros- 
tigma to tip of wing. First cubitus only slightly curved toward 
costal margin, the second strongly curved. First furcal short, 
almost straight, and meets the anal margin at a slight angle 
about one-fourth the distance from tip of clavus to tip of wing. 
Second furcal a little over three times as long as the first, 
strongly curved towards costal margin, and meets anal margin 
very obliquely. Third and fourth furcals straight, third almost 
parallel to the first, fourth about one-half longer than the third, 
and meets the marginal vein just at tip or a very short distance 
in front of it. Usually, however, the tip is acutely rounded 
and may be said to be between third and fourth furcals. The 
costal margin is in the form of a gentle curve from base 
to tip, only the curve becoming slightly stronger in the distal* 
half. Anal margin almost straight from base of anal cell 
to first furcal. Tip of clavus distinct. On anal margin near 
center of first marginal, cubital, and second marginal cells is a 
darker, somewhat triangular spot as in Trioza trvpunctota, only 
not so distinct. Greatest width of wing at union of first furcal 
with the anal margin. Wings, as a whole, very transparent, 
all the nerves very distinct, light colored, slightly tinged with 
yellow. Posterior wfings very delicate, costal margin shaped 
as usual; deeply curved at tip of clavus, broadly rounded at end 
of second furcal, strongly ascending from them to tip, which is 
comparatively rounded and between the two longitudinal veins; 
nerves all quite indistinct. The hind wings are more whitish 
than the first pair. (This appearance is probably due to a fine 
whitish pubescens.) 
Abdomen a little shorter than the thorax, dorsal portion of 
the segments dark, sides and ventral portion usually light 
green. Ovipositor very short, hardly as long as preceding 
ventral segment, roundish, furnished with numerous hairs. 
Dorsal plate the largest, its tip black. 
In the male the genital organs small and difficult to examine. 
The claspers exceed the ventral plate in length, curve towmrd 
each other, are slender, acute at tip, and furnished with numer- 
ous hairs. 
Some important variations in color, not previously given, 
must be noticed, especially the markings of the head. We can 
arrange a gradual series of specimens so that the head will be 
darker and darker until almost jet black. The same is true of 
the antennae, all being black except the basal joints and part of 
