82 N.S. ENTOMOLOGICAL SOCIETY. 



wasp.This, you will agree, is afar more wonderful a case of mimicry than 

 that of a butterfly mimicing another butterfly. 



The third figure does not, in itself, illustrate a case of mimicry, but 

 is drawn here simply as a representative of a large family of moths known 

 as sphinx or hawk moths. This particular sphinx moth, is sometimes 

 called the modest sphinx, from the fact that when at rest the sober col- 

 ored forewings lie above and hide the more beautiful hind wings. Most 

 of our hawk moths lie hidden during the day and come forth to hover over 

 our flowers in the dusk of evening. 



But here is a moth that is a true hawk moth, in development and struc- 

 ture, but which has forsaken the ancient customs of its family and flies 

 only by day in the brightest sunlight. You will see, too, it has departed 

 in appearance from the other members of its family and lost part of its 

 wing scales, and that it has developed both in shape and coloring a very 

 bumble-bee like appearance, so that to more than a casual observer, this 

 hawk-moth hovering over a clover bloom, is merely an ordinary bumble 

 bee. 



Perhaps one of the most remarkable cases of Protective Mimicry is 

 that mentioned by Thomas Belt, as occurring in Central America. He 

 mentions that certain ants use in their domestic economy fragments of 

 green leaves, and may often be seen carrying them in a vertical position 

 over thair backs, and he testifies that a certain hemipterous insect has 

 developed which closely resembles one of these ants carrying a leaf frag- 

 ment. 



There is one more principle of protective coloring that should not be 

 passed without remark. That of Signal Marking. 



It is quite obvious that for the perpetuation of any species of animal, 

 it is necessary that individuals of the same species should be able to re- 

 cognize each other. How this shall be possible without the individual be- 

 ing conspicuous to its enemies is a problem which nature has overcome 

 in many cases in this way. Many creatures are perfectly protected by 

 their coloring when at rest, but when in motion, and less easily caught by 

 their enemies, show some conspicuous marks by which they may be re- 

 cognized by their own species. 



This principle is illustrated by the insects of this plate. This tortoise- 

 shell butterfly, when resting on the trunk of a tree is simply a bit of bark 

 turned up, while in flight its upper wing surfaces are quite conspicuous. 



Again this locust when resting on the ground is only a chip of stone, 

 but on the wing shows black and yellow banners, and in addition has the 

 power to draw the attention of its friends by the loud crackling sound 

 which it is able to produce. 



