189 
it appears that this species is definitely building up in the south-central 
part of South Dakota, where in 1931 it destroyed a large portion of the 
crop in 30,000 square miles* In the egg survey, egg pods numbered as high 
as 150 per square foot in some places along field margins. 
1.1 elano plus bi vi tt atus is an important species scattered throughout 
the G-rea.t Plains States, but most numerous in parts of South Dakota, Wyoming, 
Colorado, and Nebraska. 
II elano plus packardii was rated as second in importance in most places 
where II. meric anus was so numerous. Some of these may have been M. f oedus , 
which is hardly distinguishable from H. p ackardii . Both of these species 
are noticed profusely throughout the Great Plains States in environments 
typically II. mexicanus .' 
I.ielanoplus femur- rub rum is most prominent in parts of Iowa, Wisconsin, 
Minnesota, Wyoming, Idaho, Utah, and Washington. It is the dominant species 
in the irrigated alfalfa, of Idaho and Utah. Its distribution is very gen- 
eral. 
Camnula p ellucid a is very important in localized areas in Nevada, 
Oregon, Washington, and Michigan. In the fall of 1938 it reached its 
greatest abundance in Nevada, where 350 pods per square foot were recorded 
at 1 stop. 
Aeoloplus turnbulli i , a. common species, was recorded as dominant 
in foui’ or five counties in the extreme western ‘part of Kansas. It is an 
important species in sugar beets. Last spring it was found hatching in- 
considerable numbers along the edges of fields in the irrigated sections 
around Garden City, Kans. , and elsewhere. It is unusual for this species 
to be of such economic importance. 
There were other species, such as Aulocara, clliot ti, Agencotcttix 
deorum , Brachy stola m agna , Pi ssosteira Carolina , D. spurcata , Oedaleono tus 
enigma, , Schi stoccrca sp. , and others recorded as numerous and important but 
not to the extent of those already discussed. 
The map has its limitations, because the subject matter is presented 
in such a graphic manner. The 'dominant species is considered first in the 
distribution, and the second in importance is shown occasionally. Where two 
or more species are of equal importance they are shown by an equal number 
of each of their symbols. Rcla.tive abundance is but roughly indicated in 
tho numbers of each symbol and the nap should not bo taken too literally. 
Effect of weather on the 1938 nymphal population 
In all of the heavy rain areas of ca.stcrn Kansas and Nebraska, most 
of Missouri, Iowa, Illinois, and Wisconsin nymphal populations wore kept 
down during the whole of tho nymphal season because of rains. In many 
instances the infestations on the breeding grounds, which were mostly 
field margins, were reduced from 50 to 80 percent of tho original popula- 
tion. No movements into the adjoining fields were recorded at such places. 
