MIMICRY IN BUTTERFLIES FOR PROTECTION. 



169 



Mr. Hume lays some stress on the fact that the eggs sent to him 

 ? oy Colonel Legge are much smaller than European specimens usually 

 are ; but if, as seems certain, only yearling birds breed with or near 

 us, then their eggs, being under the average, need, not excite surprise. 

 The eggs of JEyialitis cantiana, taken by Dr. Scully in Eastern 

 Turkestan, are about the same size. Below I append a table giving 

 the dimensions of the two eggs in Mr. Hume's possession, of four 

 with Colonel Legge, three of Dr. Scully, and one sent me by 

 Mr. Cumming. The first eggs of many domesticated birds are often 

 abnormally small, as every housewife knows, and I have a crow's 

 egg, taken from the nest, not much larger than a sparrow's egg. 



I have very carefully compared one of the eggs taken by 

 Mr. Cumming (which he kindly lent me) with European eggs, and 

 I find that, except in size, it does not differ: the groundcolour and 

 the markings are exactly similar, but on the other hand it differs 

 considerably from eggs of .zZ?. ■minutas, Pall {Jerdoni), of which I 

 took a large number at Neemuch. The difference is hard to explain 

 in words ; but when the eggs are placed side by side it is very notice- 

 able. The markings of the egg of minutus being more speckly and 

 scratchy and not so distinct as in eggs of cantianus, I am myself 

 quite convinced of the authenticity of these eggs. 



Dimension of Eggs of JEgialitis cantianus. 



ON MIMICRY IN BUTTERFLIES FOR PROTECTION. 



By Col. Chas. Swinhoe, f.l.s., p.z.s., f.e.s. 



That butterflies are to be found all over the world, clothed in colours 

 and patterns closely resembling their surroundings, has been lonp- 



