THE GENUS OPORABIA. 283 



thinner, especially near the tip, the incisions between the members 

 much less deep than in nebulata, the ciliation somewhat weaker, etc. 

 But Zeller {I'ijd. v. Ent., xiii., 247) says he does not find these dis- 

 tinctions substantiated in other specimens ; and Mr. Nicholson and I 

 coui])ared several examples of each species under the microscope, 

 without finding any considerable difference, though the incisions do 

 seem a little deeper in nebulata. There is, however, a mystery about 

 this question of the antennaB. Mr. Pierce has mounted several for me, 

 and wrote that here we had " a very important character," though it 

 is necessary to add that in a subsequent iettej: he wrote that "it does 

 not seem very reliable." I should perhaps hardly have mentioned 

 this note of Speyer's but for the coincidence that both Weaver and 

 Gregson lay some stress on the more slender antennae of their 

 antumnaria as distinguishing it from nebulata. (6) Thanks to the 

 kind help of Mr. J. E. E. Allen, of Bolton, I have been able to 

 examine the eggs side by side, and tonnd/Hiniaiinnaria slightly larger, 

 much more regularly shaped (true oval), less glossy, and ret/nUuiij 

 pitted tltrouijhout ; eggs of nebulata were smooth and shining, and only 

 pitted at the blunt end. (7) The newly-hatched larv* are extremely 

 similar, but ray JJli(/raniinaria were considerably larger — nearly in the 

 proportion of 4 : 8. (8) In the second, third and fourth skins, the 

 colour oi filii/raiiiinaria larvjB is more or less dark grey-green or blue- 

 green, quite distinct from the bright green of nebulata. The larvffi of 

 the latter also continued, until the final stage, very weakly marked, 

 practically unicolorous ; while filiyraiiDiiaria (as already pointed out 

 by Mr. Moberly in Ent. Rec, viii., p. 41) becomes by degrees quite a 

 striking larva, through the conspicuous yellow subdorsal lines, etc. 

 The shape and gait otjilii/raiiiiuaria IsiVvse also remind me rather more 

 of (J. bruiiiata than of (J. nebulata. The head, scutellum and anal 

 plate continue darker in /77////Y/H(;//.(/;7'rt than in nebulata at corresponding- 

 stages. The latter larva id stouter, with more pronounced segmental 

 incisions. (9) The different habits of the two species seem to be 

 sufficiently marked to add another distinguishing character of some 

 importance ; the matter of dates, localities, etc., however, remaining 

 somewhat obscure until the tree-feeding variety (or species) autuinnaria, 

 Weaver, has been more thoroughly worked out ; for if this is a variety 

 oi Jiligraminai'ia, it upsets our ideas by appearing (in Delamere Forest) 

 at the same period as nebulata, and in the same locality. 



The principal forms of O. filif/raimnaria have been discussed in 

 Mr. Clark's article, already referred to {Ent. Rec., vii., p. 289), which 

 is readily accessible. I will only say for the clearing up of the 

 synonymy, that I fell into error in accepting Guenee's citation of 

 jinlata, Westw., to the autuinnaria form. Polata, Westw. (««•. Hb.), 

 is the small Manchester and Arran form, i.e. = typicsiljiliij ram ni aria. 



As regards the distribution of filit/raiinnaria and its varieties (or 

 allies) outside the British Islands, much remains to be discovered, as 

 Continental authors do not appear capable of differentiating them from 

 nebulata. Staudinger adds "Northern Lapland, etc." with query. 

 Meves {Ent. Tidnkrift, v., p. 72) adds it to the Swedish list on the 

 authority of some specimens determined by Homeyer, and Lampa 

 retains it in his catalogue in the following volume of the same 

 Tidskrift ; but the determination seems dubious, as the distinctions 

 specified (" the reticulated markings on the almost transparent wings") 



