SUBFAMILY OEDIPODINAE 35 
structurally and others are dimorphic, thus making the genus one of 
considerable confusion in separation of species. The following key, 
which is modified from Bruner’s more general key (Biologia Cent. 
Americana) will serve as a basis for specific separation : 
Frontal costa with subparallel sides, not sulcate or carinate, broadly truncate at 
vertex or continuous with the scutellum of vertex; median carina of pronotum 
variable 
Median carina of pronotum cristate and more or less arched 
Lateral foveolae of vertex elongate triangular; carina of pronotum high 
and strongly arched carinata 
Lateral foveolae of vertex four-sided; carina of pronotum lower and less 
arched xanthoptera 
Median carina of pronotum nearly straight, not cristate or strongly arched; 
wings deep red with curved band very broad and very dark pseudonietana 
Frontal costa narrowed above to half or less than half the width below the 
ocellus, sulcate and sometimes carinate above; median carina of pronotum 
generally straight and not greatly elevated 
Frontal costa truncate at apex; wing band incomplete, not attaining the costal 
margin 
Body unusually deep at thorax; pronotum rather long, finely rugose; median 
carina moderately elevated and gently arched; hind femora robust; disk 
of wing usually vermillion conspersa 
Body more slender; pronotum shorter, the rugae coarser; median carina 
less elevated and hind femora less robust; disk of wing usually yellow 
arcta 
Frontal costa convergent above, acuminate at vertex; foveolae of vertex 
broader than long sulphurea 
Arphia carinata Scudd. 
Arphia carinata is very similar to the following species but may 
be separated by the characters given in the key. It is dimorphic in 
coloration of the wings, being found in forms varying from deep 
yellow to orange red. The coloration of the body and tegmina is also 
extremely variable, forms occurring of every shade from rich glossy 
black to reddish tan. The species does not occur until rather late and 
is not abundant until July. It prefers dry open places, such as the 
edges of fields and along railway embankments and is often very 
abundant on sandy bars along streams. It has a very strong flight 
and, when it endeavors to escape, its flight usually describes an irregu- 
lar semicircle made up of numerous zigzags, the insect invariably 
alighting with the head toward the pursuer. During flight it stridu- 
lates freely, especially at the angles or zigzags, though when sud- 
denly startled its flight is swift and almost noiseless. It occurs through- 
out Iowa in sandy areas, and within Minnesota has been taken at 
Albert Lea, Pipestone, Redwood Falls, Mahtomedi, and Fergus Falls. 
Arphia xanthoptera Germ. 
In size, general appearance, and coloration Arphia xanthoptera 
is extremely like the preceding and is subject to the same variations 
