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EN TOMOLOGY 
cumstances. Thus, one gaudy caterpillar is refused by a cer- 
tain bird, at once, or else after being tasted, but another and 
equally showy caterpillar is eaten without hesitation. Or, an 
insect at first rejected may at length be accepted under stress 
of hunger; or a warningly colored form disregarded by some 
animals is accepted by others. Moreover, some of the experi- 
ments with captive insectivorous animals are open to objection 
on the score of artificiality. 
Nevertheless, from the data now accumulated, there emerge 
some conclusions of definite value. Frank Finn, whose con- 
clusions are quoted beyond, has found in India that the con- 
spicucus colors of some butterflies (Danaine, Acrea viole, 
Deltas eucharis, Papilio aristolochi@) are probably effective 
as “warning” colors. Marshall found in South Africa that 
mantids, which would devour most kinds of butterflies, includ- 
ing warningly colored species, refused Acrea, which appeared 
to be not only distasteful but even unwholesome; Acrea is 
eaten, however, by the predaceous Asilidze, which feed indis- 
criminately upon insects—for example, beetles, dragon flies and 
even stinging Hymenoptera. The masterly studies of Mar- 
shall and Poulton strongly support the general theory of warn- 
ing coloration. 
In this country, much important evidence upon the subject 
has been obtained by Dr. Judd from an extensive examination 
of the stomach-contents of birds, supplemented by experiments 
and field observations. Judd says that Murgantia histrionica 
and other large showy bugs are usually avoided by birds; that 
the showy, ill-flavored Coccinellidee, and Chrysomelidz such 
as the elm leaf beetle, Diabrotica, and Leptinotarsa (Dory- 
phora), possess comparative immunity from birds; and that 
Macrodactylus, Chauliognathus and Cyllene are highly exempt 
from attack. Such cases, he adds, are comparatively few 
among insects, however, and in general, warning colors are 
effective against some enemies but ineffective against others. 
Generally speaking, hairs, stings and other protective de- 
vices are accompanied by conspicuous colors—though there 
