1863.] 
175 
from Eock Island.— S % % imagOj 9 imago and 9 subimago from 
Chicago.— S imago from Eed Eiver of the North.—'S imago North 
Am.— 9 imago from St. Louis.— 9 subimago from Ohio (paler.) 
Besides the above, I have an abnormal S from Eock Island, which, 
after a careful examination, I believe to be a variety of this same spe¬ 
cies. Length 20 mill. Exp. 30 mill. Seta 32 mill. Ant. leg 101 
mill, (femur 3 mill, tib. 31, tarsus 4 mill.) It resembles the % of P. 
Umbata Walsh, but is of a deeper color, the yellow less bright, the 
brown stripes wider and of a deeper color; the front legs with the 
femur, tibia, the first joint of the tarsi, the tip of the three following, 
and the whole of the last, as well as the claws, black; the four hind 
legs of a bright yellow with only the last tarsal joint and its claws 
black. Wings hyaline, marginal band of the front wings of a deep 
brown, the hind wings not bordered with brown; all the veins and 
cross veins blackish, except at the base; some cross veins in the basal 
portion of the front wings not far from the costa, and some in the mid¬ 
dle of the hind wings, bordered with black. Setae pale brown, the in¬ 
cisures scarcely marked, with the base of a few of the joints yellow 
beneath; intermediate seta present but indistinct. 
It now remains to compare this abnormal % with P. hilineata Say, 
Walsh. I have before me, besides the % from Eock Island mentioned 
above, of which the dimensions are so great, 5 S • Three from Chicago 
are very much alike. Length 18—^20 mill. Exp. 38 mill. Seta 45 
mill. Wings a little fumose, hind wings with the exterior border black¬ 
ish. Ant. leg 14 mill; hind legs yellow, the tip of tarsal joints 2—4, 
black beneath or not black. Setae brown with the basal half of the 
joints yellow. Body of a deep color. Abdomen long^ with two yel¬ 
lowish or fulvous spots on each joint. One % from Eed Eiver of the 
North, (determined as hilineata Say, by Mr. Uhler,) resembles the three 
from Chicago, but the band at the tip of the hind wings is subobsolete. 
Finally, a % without any precise habitat, with the band of the hind 
wings altogether absent. I remark that the relative proportion of the 
tarsal joints is far from being constant; for I see that 3 is sometimes 
as long as 2, sometimes shorter, and even one-half shorter ( S Uhler.) 
The % from Eock Island is large, its setae and legs are longer and its 
wings more fumose. [Nee note 17.] 
It seems to me that the shortness of the front legs, in common with 
