164 EVENINGS AT THE MICROSCOPE. 



The mode in which they are arranged is in a short spiral, 

 which makes about forty-five whorls or turns about the 

 axis ; at least in the branches which are situated about 

 the middle of the antenna ; for these diminish in length 

 towards the extremity, bringing the feather to a rather 

 abrupt point. 



The entire surface of the branch gleams under reflected 

 light with metallic hues, chiefly yellows and bronzy 

 greens ; which appear to depend on very minute and 

 closely-applied scales that overlap each other. The main 

 stem of the feather, — that is, the primary rod or axis, — is 

 somewhat sparsely clothed with- scales of another kind, 

 thin, oblong, flat plates, notched at the end, and very 

 slightly attached by means of a minute stem at the base, — 

 the common clothing-scales of the Lepidoptera, — speci- 

 mens of whieh we have before examined. 



PORTION OP ANTENNA OP OAK EGGEI1 MOTH. 



We may acquire some glimpse of a notion why this 

 remarkable development of antenna? is bestowed upon the 

 male sex of this moth, by an acquaintance with its habits. 

 It has long been a practice with entomologists, when they 

 have reared a female moth from the chrysalis, to avail 

 themselves of the instincts of the species to capture the 



