IDENTIFICATION OP ACIDALIA DILUTABIA, HB. 125 



on either of the wings " ; in many the spot is faint, in a few, again, it is 

 quite distinct, though I think always more minute than in the allied 

 species ; some specimens have a slight tendency to darkening on the costa, 

 though it is never at all pronounced ; but two or three have fine dark 

 outer mavf/ins, such as I never before saw in any of the three species in 

 question ; and one has all the transverse lines strikingly distinct and 

 dark, yet the transitions are so gradual that it would be impossible to 

 make separate species of them, even if they had not been taken at the 

 same time and in the same locality. The dark outer margin and the 

 dark transverse lines are especially important as helping to fix the 

 identity of Hiibner's dilntarla ; they are two of the chief par- 

 ticulars in which it seemed so hard to reconcile his figure with 

 interjectaria, Bdv. ; but still more, the differently shaped wing in the 

 said figure, with its prolonged apex, gave it a totally different aspect, 

 but finds its counterpart in some of Mr. Tutt's series of holoserieata. 



It is by no means a new discovery that the last-named species has a 

 variety with distinct central spots ; Guenee made the discovery while 

 his work was in progress, and records it in his addenda (Ur. ct Phcd., 

 ii., p. 543). But he probably did not again refer to Hiibner's figure 

 100, which he had already made up his mind was his interjectaria. 

 Specimens in the series from the Zeller collection, labelled Bergiin, 

 Preth and Raibl, have also perceptible central spots. 



The six characters which Guenee specifies, whereby holoserieata 

 may be distinguished from its allies are : the perfectly rounded wings, 

 the fore-wings more prolonged at the apex, the more clayey colour, the 

 lines nearly equidistant, the concolorous costa, the absence of the 

 discoidal spot. The fourth and sixth of these are found to be incon- 

 stant ; the second and fifth certainly agree entirely with Hiibner's 

 figure of (liliitaria ; the colour of Hiibner's figure is not good, and is 

 partly responsible for my never even dreaming of associating it with 

 holoserieata ; but I find that after all it really diflers but very little from 

 the two palest in Mr. Tutt's series. 



In fine, with this series and Hiibner's figure side by side before me, 

 the conclusion is absolutely irresistible that they are specifically 

 identical, the figure representing the extreme form with dark trans- 

 verse lines, dark outer margin and distinct central spots. 



Perhaps it may be well to add that oiw British A. holoserieata, so far 

 as I know it, appears to be a somewhat specialised local race, and to 

 vary very little, if at all. I do not recollect ever to have seen it with 

 the central spots more than very faintly traceable, and certainly never 

 with the outer margin darkened. I fancy the tone of colour is also 

 slightly more yellowish or brownish than in some of the Continental 

 examples. 



It would, I am afraid, be useless to endeavour to get the name 

 dilutaria, Hb., restored to the right species ; but there ought to be no 

 great difficulty, in this country at any rate, in restoring the correct 

 name interjectaria, Bdv. (which is still used by some Biitish entomolo- 

 gists), to our much enduring " Bone Wave," ignoring altogether the 

 name of dilutaria. But, to my mind, there is not the slightest doubt 

 that the correct course would be to alter the name of Imlosericata, 

 Dup., and let it stand thus : — dilutaria, Hb., fig. 100 {nee al. auct.) ; 

 straiiientata, Ev., Bull. Mosc, 1842, iii., p. 56G (with central spots) : a. 

 ab. holoserieata, Dup. (without central spots) . 



