MEXICAN BEAN BEETLE IN THE SOUTHEAST. 1. 
from Colorado were planted with a legume collection on the experi- 
mental plats. Careful counts showed that more than twice as many 
adults were present on the pinto beans, and they were destroyed 
sooner than a collection of six of the most popular varieties of garden 
bush beans. In 1922 tepary beans were decidedly preferred to 11 
varieties of the commonest pole and bush beans, although the leaves 
were small and the insect was exposed to the sun. These facts 
support the statement that the bean beetle was introduced from the 
western part of the United States, for these varieties are grown 
extensively there. 
HIBERNATION. 
Knowledge of the hibernation habits of the Mexican bean beetle 
previous to the winter of 1921-22 was based on the collection of 
very few specimens during the fall and winter. The greater portion 
of the life cycle of many important injurious insects, especially in 
the Temperate Zones, is passed in a dormant state during winter, 
but in many instances little is known about this stage. Attack on 
insects during this period has been found successful in notable cases, 
such as the clean-up practices recommended in some localities against 
the chinch bug, Blissus leucopterus Say, and the planting of wheat 
to take advantage of the seasonal life history and hibernation habits 
of the Hessian fly. Other outstanding examples might be mentioned. 
The adult of the bean beetle is the only stage which survives the 
winter. In 1921 emergence from hibernation was first noted March 
_ 22, when four adults were collected on early beans. An egg mass 
was also collected, indicating that emergence had occurred a few 
days before. In field observations emergence and spring migration 
lasted until the middle of May, the greatest number having emerged 
_ by late April and early May. 
__ Restlessness of adults in the field was noted in August, 1921, and 
_ from that time until late October migrations occurred. Beetles were 
_ exceedingly numerous until that time, but had almost disappeared 
_ from the field by November 4, when a heavy frost occurred. <A few 
_ specimens were observed up to November 25, 1921, on parts of bean 
foliage which had not been killed by frost. 
_ Adults of the Mexican bean beetle have been found hibernating 
/ under various conditions. They have been collected in old stumps 
near a garden, in cracks of old fence posts, in débris about an old 
fence, in stone piles near a garden, under leaves and plant remains 
in the garden, under a woodpile, and in well-drained woodlands 
_ near bean fields. 
__ Experience gained in California in investigating the hibernation of 
' beneficial coccinellids led J. E. Graf to believe that the Mexican bean 
beetle, which is a coccinellid, hibernates similarly. Therefore, a 
_ large area surrounding the Birmingham trucking district in the East 
Lake section was carefully searched for the beetle during the winter 
| of 1921-22. The results are given in Table 4.4 
_ This area comprised approximately 12 square miles and the same 
territory was searched again in the winter of 1922-23. These results 
are shown in Table 5. 
4M. P. Foshee, D. M. Dowdell, Jr., and others assisted in this work. 
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