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flower, or sucked peacefully at the blossoms, a quiet species, almost 

 overlooked, at first, on account of its comparative rarity, was oc- 

 casionally to be noticed among the brilliant company. This proved 

 the most puzzling of all our numerous captures. The males, some- 

 what larger than an ordinary Z. lonicerce. had five crimson spots 

 and were in no way distinguishable, at a first glance, from speci- 

 mens of Z. atigelicce; but a more complete and thorough examination 

 revealed an ill-developed sixth spot, situated somewhat closely 

 underneath the upper well-developed spot near the apical portion 

 of the wing. On the underside this faintly-marked spot was rather 

 clearly developed. Paired with these were some very large females 

 which at first reminded us somewhat of Z. medicaginis, but the 

 presence of a small sixth spot, better developed than in the males, 

 but still much less well-developed than is ordinarily the case in 

 other six-spotted species, at once marked this comparatively rare 

 species off as quite distinct from anything else we met with in 

 our wanderings. The persistency and regularity with which this 

 small spot appeared, and the constancy of its ill-developed ap- 

 pearance were very remarkable. At first sight one got a very 

 decided impression that the insect belonged to a five ralher than 

 a six-spotted species. 



It is well-known that all the six-spotted species of Burnet moths 

 have a tendency to lose occasionally the lower spot of the outer 

 pair. Such aberrations are not at all rare and denote either (i) 

 an evolution towards a five-spotted form, if the five be a more 

 newly-developed form than the six-spotted, or (2) an evolution to- 

 wards a six-spotted form if the latter be of more recent develop- 

 ment. They occur rather frequently among typical specimens of 

 Z. filipendulce and Z. transalpina, but in no case do they appear 

 to occur except as occasional aberrations. 



I have pointed out, in my notes on Z. medicaginis, the proba- 

 bility of this six-spotted species having been mixed with that in 

 Staudinger's diagnosis under the name of var. dubia, but it may be 

 better to leave the final consideration of this point until later. 



Among various species sent to me as Zygcena filipendidcB var. 

 ochsenheimeri, have been some veritable filipendiilcB, together with 

 specimens of the form now under discussion. Although I have 

 probably one of the largest collections of British Zyggenidse (ex- 

 cepting, of course, that of Mr. W. H. B. Fletcher) and know 

 Zygcena fjipendulce well, it never struck me, when capturing and 

 observing the specimens that they had either the habits or general 

 appearance of Z. filipendulce, neither did Dr. Chapman connect it 

 in any way with that species. Much, as it would appear, in the way 

 that doubtful European species with five spots gradually slide into 

 what are usually considered vars. of Z. trifolii, so this species, 

 owing to its resemblance to occasional aberrations of Z. filipendulce, 

 has been merged into the latter. The constancy of position of the 

 ill-developed spot and the general appearance of the insect alive 



