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Insects. 



in advance in this matter ; at all events he has not told me of any. I should have 

 been much pleased if Mr. Doubleday had given us his opinion, for he received some 

 of the larvae of P. Agestis from me ; but again, Mr. Nevvman states that I leave un- 

 touched the evidence of the present year. In answer to this, I state that I have no 

 fresh evidence ; the larva; are the same, their food-plant is the same, and their manner 

 of feeding is as it was eight years ago. I expected to have the evidence of Mr. Newman 

 and others to prove that they were one and the same, but it now appears that lime, 

 that great unfolder of events, must decide the question. One word before closing 

 this subject, to Mr. Harpur Crewe ; he says he knows nothing of the larva of P. Ages- 

 tis, but thinks it ought to revel on the top of its food, as its brother P. Argiolus does, 

 and is at a loss to conceive why I have condemned it to so hard a fate. I hereby 

 inform Mr. Harpur Crewe that I had no hand in the matter, any more than he had in 

 condemning P. Argiolus to be exposed on the top of a holly-tree when its brother was 

 snugly ensconced under its food-plant; but it is such circumstances as these that 

 prove a difference of species. One word more: I hope that this subject will set others 

 on the look-out for the larvae of P. Agestis ; by this means we may arrive at the truth. — 

 //. J, Harding ; 1, York Street, Bethnal Green, October 14, 1858. 



The Distinclive Differences between Polyommatus Agestis and 

 P. Artaxerxes carefully considered. By G. Wailes, Esq.* 



Let us now consider the points of distinction relied on. They seem 

 to be, — -Jirst^ the marginal band of orange spots ; secondly^ the black 

 or white spot in the upper wings ; and, thirdly^ the ocellated or non- 

 ocellated white spots on the under side. As to the first, there is no 

 doubt that this band of orange spots is generally most fully developed 

 in the southern localities ; but the supposition, that it always decreases 

 as we proceed northwards, is certainly erroneous ; for some of the 

 finest and most brilliant specimens in this particular that I have seen 

 are from parts as far north as Liverpool, from our own district, and 

 from Edinburgh ; those from the two last localities bearing the white 

 spot of P. Artaxerxes. We may therefore, I think, safely dismiss this 

 band as any criterion of specific difference. 



Next, as to the black or white spot on the upper wings. It would 

 appear that throughout the continent of Europe, widely difi'used as I 

 shall hereafter show P. Agestis to be, not a single specimen has been 

 recorded as deviating from the type, even in latitudes much colder 

 than our own, whereas, in Britain, it extends northwards as far as our 

 most northern local habitat, Bamborough, mingled from Richmond, in 

 Yorkshire, with the Artaxerxes form. Even in the most southern 

 parts of our island we have a few examples recorded which link the 



* In ' Catalogue of the Lepidoptera of Northumberland and Durham/ p. 29. 



