DEATH FEIGNING IN CONOTRACHELUS NENUPHAR 
HERBST. 
WILson P. GEE and F. H. LATHROP. 
Peculiarities in behavior of insects have many times been 
used with distinct advantage in the control of injurious forms. 
The heliotropic reaction of moths—that is, their tendency to 
fly towards the light—has given rise to the trap lantern; and 
a knowledge of the nocturnal habits of the malarial and yellow 
fever mosquitoes has made it possible for the diseases caused 
by these insects to be avoided by housing oneself during their 
period of activity. One of the most striking cases of the direct 
economic application of an instinct in insects is that of death 
feigning or ‘“‘playing possum” in the plum curculio, Cono- 
trachelus nenuphar, Herbst. 
It is true that the introduction of arsenical sprays marks 
an epoch in the control of the curculio, and quite deservedly 
has caused the old method of “‘jarring”’ to be largely superseded 
by the newer one of spraying. The practice of “‘jarring’’, 
however, is still in vogue in sections where the spray pump has 
not come into general use. Therefore, a study of the features 
of the instinct is of interest, not only from the biological point 
of view, but also due to the fact that at a not remote time it 
provided the most effective measure of control for the plum 
curculio. 
In speaking of the preventive measures for lessening the 
injury of this pest, Johnson and Girault (8: 1906), of the Bureau 
of Entomology, U. S. Department of Agricultute, have the fol- 
lowing to say: ‘“‘Among these jarring is the method which is 
perhaps in most general use in protecting plums and peaches, 
and by many orchardists it is believed to give the best results. 
Early observations upon the plum curculio showed that this 
insect has a habit of falling to the ground and “‘playing possum”’ 
when disturbed. A knowledge of this habit has led to the 
capture of the beetles on sheets, held or spread beneath the 
trees, the trees being jarred by a sudden forceful blow struck 
with a padded pole or mallet in order to dislodge the beetles.”’ 
A field test of the efficiency of the method made by these same 
men in a Georgia orchard showed “that the amount of the 
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