VARIATION OF VANESSA URTIC^. 83 



from the Piz Europa, serve to bring out very strongly the diffe- 

 rences between the two species ; though they are as small as 

 the smallest varia, it would be almost impossible to confuse 

 them. The only females I have ever seen about which any 

 uncertainity could arise are the very light specimens taken by 

 Mr. A. H. Jones at Campfer, in the Engadine. 



(To be continued.) 



VAEIA.TION OF V. URTIC.F., L. 



By T. Eeuss. 



Since I began, in 1906, to pay some attention to the facial 

 changes possible in the Vanessidre, I have taken particular 

 interest in any variation exhibited by the normally dusky, plain- 

 hued under sides of urticce, io, polychloros, and others. As is 

 well known, the under sides of these imagines are undoubtedly 

 under certain conditions of protective value to their possessors, 

 by causing them to resemble bits of wood, dry clay, &c. Any 

 new departure in facial development, tending to paint bright 

 decorative colours into such under sides and thus to deprive 

 them of, or to lessen, their protective value, would naturally be 

 worth while to observe. 



Now though I have reared over twelve thousand larvas 

 of V. urticce and io* only three or four perfect individuals have 

 come to my notice, which plainly showed the tendency to 

 develop an under side facies with conspicuous colours in it. 



On September 13th last I bred the above aberration of V. urticce 

 from wild Hertforshire larvae, which is remarkable for the chain 

 of light bluish-grey lunules on the under side of the wings. 

 Groups of shining white scales in the lunules brighten them 

 and, in the live insect, the lunules looked very conspicuous and 



'•' A specimen of V. io (a heat-form) developed a few brilliant metallic 

 blue and green scales at the apex of the fore wings, just underneath one of 

 the white spots in the ocellus, and in the same place where such metallic 

 scales are to be found in the under side of Polygonia {Vanessa) c-albtcm. 



