XL 



THE EGGS OF BUTTERFLIES 



The eggs of butterflies, except tliose of the 

 gigantic Ornithopteras, are no larger than a pin's 

 head, yet when examined under a lens, which is of 

 course required to see the structure of such minute 

 objects, we may look far before discovering any- 

 thing more graceful in form or delicate in sculp- 

 ture ; indeed, chancing to study some of our forms 

 during a winter spent in Egypt, I was greatly 

 struck by their singular resemblance to the trace- 

 ried domes of the famous Cairo mosques. They are 

 composed of a thin, elastic, and usually transpar- 

 ent pellicle — so elastic that they will bound like a 

 rubber ball when falling on a hard surface ; where 

 not transparent they are made opaque by cross- 

 lines or ribs, by a general reticulation, or in some 

 lower forms (Pamphilini) by a uniform density of 

 the whole integument. They are always circular 

 in cross-section, and in general are flattened on 

 the surface of rest; by their form they may be 



