-15- 
« 
the outer two-thirds of this margin a second row of somewhat 
longer and more slender hairs. On the surface of the wing are two 
parallel longitudinal veins, set with stout spines, the median one 
extending the entire length of the wing. In a favorable light the 
posterior vein can be seen to arise from the anterior at about one- 
fourth of its length from the base. The entire surfaces of both 
wings are set with minute spines. The hind wing is heavily 
fringed along the posterior margin, and sparsely set with short cilia 
along the anterior margin, and there is a faint median nerve. 
The antenna [Fig. 12 a] appears to have but seven joints, even 
when viewed under a high power of the microscope. It is only 
with the most careful focusing and arrangement of the light that a 
possible minute eighth joint can be seen. In no case has it been as 
plainly seen as represented in the illustration. 
This insect differs from the original description of T. striatus■ 
by having two rows of spines on the anterior wings, and by having 
the row of spines on the costal margin of the wing continued to the 
base. The paired spines on t\\e last abdominal segnent [see I ig. 
12 c] would seem to us to put this insect in genus Lixiotltrips. 
Should the species prove to be new, we would suggest for it the- 
name Limothrips allii. 
There were certainly many hundreds, if not many thousands,, 
of this insect in all stages of development upon single onion plants 
in this vicinity the past two summers. The young are usually 
found most abundant in the axils of the leaves. 
Besides attacking the onion, this pest is common in various 
flowers, where it probably feeds upon the pollen or tender parts of 
the blossom. 
Cucumbers are sometimes severely attacked by Thripidse in 
this State, causing the leaves to turn white and die. From an ex¬ 
amination with a hand lens, the species doing this injury appeared 
identical with that on onions. 
(Coleothrips trifasciata Fitch.) 
i 
This insect also belongs in the family Tliripidx, but to a differ¬ 
ent genus ( Coleothrips ) from the preceding. It is black in color, and 
measures one-eighth of an inch in length. The name trifasciata 
was given it bv Dr. Fitch, because of the bands across the lore 
wings—one at the base, one at the tip, and one about midway be¬ 
tween these. This insect, which Dr. Fitch found common on wheat 
and in flowers of tanzy, we have found common upon onions in 
company with the preceding species. It is also common here in 
blossoms of alfalfa, wild sunflowers, and clover. 
