dingily colored surfaces. But many kinds are too promiscuous in their perch- 

 ing habits to profit by highly specialized coloration. Some have transverse, 

 opaque, obliterative bands of dark brown on their fair, transparent wings, 

 which would otherwise often be made conspicuous by their unbroken glisten- 

 ing. So also these flies' big, composite eyes are sometimes richly iridescent, 

 and therefore, amid appropriate surroundings, well 'obliterated.' 



The slender-bodied Diptera, such as gnats, mosquitoes, 1 long-legged dad- 

 dies,' etc., show few or no very remarkable developments of protective color- 

 ation. Being perchers on tree trunks, branches, and the dead-leaf covered 

 ground, rather than on flowers and green leaves, they are usually dull colored- 

 brown or grayish. Few have noteworthy body-markings, but many are 

 obliteratively shaded. Their transparent (and often daintily iridescent) wings 

 are sometimes marked with obliterative spots or transverse bands of dusky— 

 as in some of the well-known and well-hated Anopheles mosquitoes, and some 

 of the 'long-legged daddies' or crane-flies {Tipulidce)— while in others the wings 

 are dusky brown with various opaque white markings. In fact, with a good 

 many dipterous insects obliterative wing markings largely take the place of 

 body markings, and the two broad wings when flatly folded amply mask the 

 body, from a top view. 



Wingless Hymenoptera, or ants in their apterous phases, largely lack not- 

 able obliterative or mimetic (?) devices, apparently relying for defense on their 

 strong biting jaws and sharp acid excretions, as well as their extreme bodily 

 toughness,— and passing much of their time in dark retreats of their own 

 making. Their prevailing color is black or dusky brown, without obliterative 

 shading. But some are tawny yellowish, some rust-brown, and some wear two 

 or three of these earth-colors (including black), in clearly defined, unflecked 

 'ruptive' patches. Despite the sharply pungent acids they contain— doubt- 

 less effective against some predators, ants are a favorite prey (sometimes even 

 the sole (?) diet) of certain birds and beasts, and it is somewhat curious that 

 they have not more highly developed disguises. Protective coloration would 

 not avail them, however, against the most greedily and exclusively f ormicivorine 



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