OPOEABIA AUTUMNATA. 59 



The fourth female from which any specimens were bred was 

 the one figured on Plate I. fig. 12 (ab. tyjnca, Clark), but as only 

 three emerged it would be rash to generalise from them ; all the 

 three agree pretty well together, being rather weakly marked, 

 and rather paler than the parent, which they do not in any 

 respect incline to follow at all closely. 



The very fine large male figured on Plate I. fig. 6 was taken 

 at Eannoch in 1897 ; those who hesitate to acknowledge fili- 

 grammaria as a form worth keeping distinct from aiUnmnata 

 should consider such specimens as this before deciding to 

 abandon the latter name. It would only increase the confusion 

 which already exists to begin to write of these great woodland 

 forms as " jUigi-ammaria.'" There is an unnamed Oporabia 

 species from Esquimalt in our National Collection, of which this 

 specimen much reminds me in the rugged appearance of its 

 markings. 



The examples of filigrammaria and of dilutata figured on 

 Plate 11. may to a large extent be left to speak for themselves. 

 Figs. 3, 5, and 6 were all bred by me from the same female, 

 from Bolton ; fig. 6 is Herrich-Schsfier's type form of Jili- 

 grammaria, fig. 4 a female aberration ; figs. 3 and 5 (the latter 

 bred by me in 1899 from Huddersfield ova) represent two fairly 

 representative males, and may be useful for comparison with 

 some of the autumnata males. 



Figs. 7 and 8 show the male and female of a form of dilutata 

 which has interested me immensely, and for which I have pro- 

 posed (Ent. Eec. xi. p. 122) the name of ab. (?var.) christyi. 

 Mr. Christy brought ten of the form (eight males, two females) 

 from a birch wood at Eannoch in 1897, including the male which 

 is figured ; and eight more (four males, four females) in 1898, 

 including the figured female. Except that four of the 1897 

 specimens (three males, one female) were slightly infuscated, the 

 form hardly varies appreciably, and it is in many respects so 

 closely parallel to duenee's autumnata (var. gueneata, mihi), 

 especially to his figure (Atlas, pi. 18, fig. 7), that for a long 

 while it greatly mystified me. The respects in which it agrees 

 with autumnata var. gueneata are: — 



1st. The comparative absence of sexual dimorphism, and the 

 approximately equal size of the sexes. 



2nd. The weakness of the markings, except at the costa and 

 on the nervures. 



3rd. The tendency to angulation of the "elbowed line" 

 (extremely rare in ordinary dilutata). 



4th. Its attachment to birch. 



The proofs, however, that it is not a form of autumnata are : — 



1st. The male genitalia agree with those of dilutata. 



2nd. The ground colour has somewhat of the dirty yellowish 

 tinge which is wanting in autumnata. 



