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MINNESOTA 
This is the fourth year that collections have been made in Minnesota. 
They were made in 1935, 1936, 1937, and 1938. During the past season, 
14,402 specimens were taken in 8 major environments. Of these 25.3 percent 
were immature forms of undetermined species. In the collections the dominant 
species was M, femur- rub rum in all of the habitats except flax, where M. 
mexicanus was most numerous. M. mexicanus is second in numbers and Ageneotettix 
deorum is third. This, however, does not speak the truth for the situation 
for the western part of the State and the Red River "Valley, into which 
enormous numbers of M. mexicanus migrated in July and August. Cannula 
pellucida and M. bivittatus were the two most important species in the 
State from 1932 to 1936, inclusive. Beginning about 1935, M. femur- rubrum 
has steadily increased in relative numbers and importance, M. mexicanus 
began in 1936 to increase its importance. Another outstanding fact was the 
increase in Li. diff erentiali s in the southwestern counties. No specimens 
of. this species are recorded in the 1935, 1936, and 1937 collections. In 
1938, there were 239 specimens taken, which is 1.66 percent of the total of 
14,402 specimens of all species collected in the State. It ranks third 
in corn and potatoes . reaching its greatest relative importance in corn at 
11" pehebn't and is sixth in the total numbers collected. 
Hatching began the second week in May and continued rains delayed 
and prolonged it throughout May and June. Nymphs of M* femur- rub rum were 
still, numerous in September, t Heavy baiting was done throughout July and 
August against the migrating swarms of M. mexicanus into the Red River Valley 
areas. Owing to these migrations, the grasshopper potential as found in 
the 1938 survey is over one and one-half times that of 1937. 
