PllOTECTIVE MIMICRY. 203 



two of these species cannot fail to impress the reader with 

 their bee-like form. 



These resemblances, undoabtedly striking though they are, 

 must be discounted by the fact that the whole family of Glear- 

 wings have a general resemblance to Hymenoptei'a.* 



Dr. Seitz has published from a diary kept in Brazil a number 

 of interesting cases of mimicry among Lepidoptera. 



A species of Trichiura closely resembles an ichneumon fly ; 

 the ichneumon in question has brownish wings, with a yellow 

 spot on each ; the wings are kept folded against the body 

 when the insect is settling upon a leaf ; the Lepidopteron gets 

 the same appearance by an altogether different method, which 



Fig. 25.— Hornet Clearwiug. 



is most remarkable, and exceedingly suggestive of purely 

 adaptive mimicry. The wings are nearly transparent, but while 

 they are kept closely pressed against the body they appear 

 brownish (the colour of the body), and a yellow spot upon the 

 abdomen is seen through the transparent wings, and thus pro- 

 duces a precisely similar effect to a spot upon the wing, which 

 occurs in the mimicked ichneumon. The ichneumon has, of 

 coiu'se, its long ovipositor with two sheaths, or rather the two 

 halves of the sheath ; these are imitated by three j)rocesses in 



* Mimicry has even been the cause of mistakes in entomology, the 

 mimicking species having been occasionally confounded with the mimicked. 



