SUBFAMILY ACRIDINAE 93 
great loss, especially in those parts of the State where the culture 
of cereals is the rule. It is too generally known as the two-striped 
locust to demand much description, but we may say briefly that it is a 
large locust with two light-colored dorsal stripes and a general 
coloration of fusco-testaceous, or occasionally a dark brownish or even 
drab tone. The furcula of the male is present though very short and its 
forks are indicated as broad triangular teeth projecting from the last 
dorsal segment and rather widely separated at the base; the cerci 
are very stout, large and broad, laminate, externally more or less 
convex, the basal half narrowing gently; beyond the middle rather 
abruptly expanding into two lobes, the upper much larger and nearly 
the length of the basal half of the cercus, while the lower is brief 
and triangular ; subgenital rather narrow, subequal and at apex slightly 
elevated and somewhat prolonged. This species is common in all 
parts of the State and at times abnormally so. In Lowa this insect 
matures about June 10, and in Minnesota about a week later. Mating 
occurs here early in July and the earliest oviposition we have noted 
in the field was August 8. The female of this species, as in others of 
this genus, deposits egg masses more than once during the season. In 
cages we have taken three egg masses from the same female. The 
insect does not appear at all particular as to the kind of soil in which 
the eggs are placed, since it has been observed drilling and ovi- 
positing in such varied places as hard packed roadbeds, sod, gravel, 
railway embankments, sandbars, stubble fields and soft soil far out in 
fields of corn or potatoes. The number of eggs per pod varies greatly 
as pods have been taken which contained from 39 to 82 eggs. The 
freshly moulted insects are often of a beautiful light green tint, with 
the light dorsal lines faintly indicated but the color soon darkens to 
normal. The nymphs are to be found in varying colors and, in fact, 
at times the individual nymphs vary in different instars. 
Like most species of this genus this insect is subject to attacks 
from a large number of enemies, including not only insects and fungus 
diseases but also birds, mammals, reptiles, and even batrachians and 
these varied natural controls serve to reduce its numbers greatly. 
M. femoratus Burm. is identical with M. bivittatus in size, general 
appearance and form of cerci and furcula, but differs mainly in the 
fact that the posterior tibiae are red (Plate II, 5,6, and 7). It 
can: but be considered as a mere color form of this species by one 
observing the two in the field. It has no more basis for specific 
distinction than have two other color forms which we have occasionally 
taken—one in which the hind tibiae are clear yellow throughout, and 
the other having the hind tibiae entirely and almost uniformly dark 
rose purple. All of these color forms, including the one termed 
