VARIATIONS OF NYSSIA LAPPONARIA. 



249 



terminating in a cluster of much finer bristles ; the spiracles are 

 whitish and prominent. It remains from about ten to fourteen 

 days in the pupal state, according to temperature. 



The first imago emerged on Sept. 6th, the last on Sept. 18th, 

 1904. 



VARIATIONS OP NYSSIA LAPPONARIA. 

 By E. A. Cockayne. 



On looking over the males of Ni/ssia lapponaria which I 

 captured or bred at the beginning of the year, I find that, far 

 from being extremely constant, they show a considerable range 

 of variation. As a whole they appear to be paler than those 

 captured by Mr. Christy, though I have only been able to com- 

 pare them myself with the one in the Hope Collection at Oxford. 

 This corresponds to my darkest specimens, which form a small 

 proportion of the whole number. 



These darker individuals have three very distinct blackish lines 

 and a broad marginal band on the primaries, separated into two 



