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FRUIT FLIES 
Through the use of traps set in the uncultivated lands of northern 
Mexico, data were accumulated during 1935-3^ which greatly strengthened 
the theory that Anastrepha ludens Loew is a rather migratory species. 
Flies were trapped in locations many miles from any lenown wild or culti- 
vated host and in an arid country that probably would not sustain a grow- 
ing fly population throughout the year. The recurring infestations in 
the Rio Grande Valley probably result from flie3 that have reached this 
area from Mexico. It is "believed that most of the flies trapped in 
northern Mexico and Texas originated in the heavily infeste-: area about 
125 miles south of the border. There is growing along the mountains of 
northern Mexico a favorite host, Sar.ientia gregli , which fruits in the 
summer. Apparently adults leave this host when the fruit is gone late 
in the summer and at least part of them migrate northward in search of 
food and fruit for oviposition. Some of them eventually reach the Rio 
Grande Valley. The same conditions, apparently, that cause the flies 
to immigrate into the valley during the fall also force them to emigrate 
during the spring. 7/hen the fruit is removed from the trees during the 
harvesting season, the flies seem to leave the harvested grove also, and 
when the host-free period is in effect no flies are trapped in the 
valley. The trend of migration seems to continue northward, as flies 
are regularly trapped in the brush north of the valley late in the season. 
BOLL WEEVIL 
The damage caused by the boll wo vil in 193& was probably less 
than it has ever been in any year since it became widely distributed 
over the Cotton Selt. The only areas that suffered more than normal 
damage were tho east- rn and southern parts of Texas. The light damage 
in 193^ was cause 1 by a combination of factors. The weevils entering 
hibernation in the fall of 1935 were more numerous than usual in South 
Carolina and eastern Texas but less so than usual in Mississippi, Loui- 
siana, and Oklahoma. The abnormally low winter temperatures caused a 
heavy mortality and the lowest survival in the hibernation cages ever 
recorded at Florence, S. C. , and no survival at Eufaula, Okla. Tho 
survival at Tallulah, La. , was also much less than normal but at Col- 
lege Station, Tex., it was several times higher than usual. The gen- 
erally low survival over most of the Cotton Belt was followed by a 
v ry dry spring, with extremely high temperatures in May and June, 
which further reduced the numb-r of we 'vils, except in east rn Texas. 
The drought was more prolonged in Oklahoma, wh-^re only 2.11 inches of 
rain foil in the 99 days from June S to September lU, and the weevil 
infestation was practically wiped out. At Tallulah, La., approximately 
90 percent of the grubs in the infested squares were killed by climatic 
conditions during the latter part of June. As a result of the low sur- 
vival and climatic control, the infestation did not build up to the 
