TRIFIDJE. 333 



Another form of very dark purple-brown colouring, but the 

 transverse lines and stigmata all yellowish, and the former 

 rather spread and clouded, was known as A. clubia. A still 

 more extreme form in which the yellowish colour runs in 

 slender longitudinal lines is probably what was known as 

 A. Marshallana, though this is not so certain ; but the 

 identity of all as one species has long been recognised, 

 and all are so inextricably blended together by every shade 

 of intermediate variation, that even as varietal names the 

 value of these designations is doubtful. The last named 

 appears to be the most rare. I have taken it on the 

 Norfolk coast. Typical specimens of nearly all these 

 forms with the original names attached, from the Haworth 

 collection, still exist in that of Dr. P. B. Mason, at Burton- 

 on-Trent. Mr. F. J. Han bury possesses a specimen having 

 the purplish front margin of the fore wings as in A. rcwida 

 which it curiously resembles ; and another which has before 

 the hind margin a distinct row of short, black wedges. A 

 beautiful specimen taken at Howth, near Dublin, by Mr. G. V. 

 Hart, is of a rich deep black, with the reniform stigma 

 edged with yellowish, but the other markings very indistinct ; 

 its hind wings are not unusually dark. The more brightly 

 marked forms seem to preponderate in the Cambridge Fen 

 district, but in most localities the dull and obscurely marked 

 varieties are in an immense majority. 



On the wing in the latter part of July and in August. 



Larva when full grown an inch and a half long, smooth 

 and cylindrical. The colour of the back ochreous-brown 

 and in some individuals very bright ochreous ; a thin grey 

 dorsal line margined with blackish, and running throuo-h a 

 series of blackish-brown triangular and diamond shapes is 

 well defined in some individuals, though obscure in others. 

 Subdorsal line greenish-black, in some varieties quite black, 

 and edged below with a narrow line of dirty whitish-green, 

 then a broad stripe of blackish-green, followed by another 



