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XXI. A Contribution to the Life History of Agriades escheri, 

 Hb. By T. A. Chapman, M.D. 



[Read October 6th, 1915.] 



Plates LXXXIII-CIII. 



My interest in Agriades escheri arises from the investigations 

 about Agriades thersites, since it appeared that thersites was, 

 notwithstanding its close resemblance to P. icarus, not at 

 all nearly related to that species, but was in many respects 

 so similar to A. escheri as to suggest that escheri and thersites 

 were quite recent derivations of a form very close to escheri. 



There seemed, however, to be no published life-history 

 of A. escheri, nor, so far as I have been able to learn, any 

 figure of the larva, though its food-plant is referred to by 

 several authorities, the original information apparently 

 being from Saporta for Astragalus incamis, and Donzel for 

 Astragalus monspessidamis, though I have not found where 

 they published these facts. It curiously happens that in 

 the Bulletin of the Entomological Society of France (1915, 

 No. 8) there is reported " Notes on Lycaenid larvae by 

 Monsieur P. Chretien," read 28th April, 1915, amongst 

 which is a fuller account of the life-history, running to 

 a page of the Bulletin, than had previously appeared 

 anywhere. 



He also has notes on L. orbitulus and L. eros whose larvae 

 he appears to have known for some time. 



It appeared desirable, therefore, to learn something of 

 the Hfe-history of A. escheri. I failed, however, in 1913 to 

 obtain any ova, and so the observations had to be postponed 

 to 1914. ' 



On the 28th April, as noted in Trans. Ent. Soc, 1914, 

 p. 482, I visited the locality on the way to Berisal, where 

 Astragalus exscapus grows freely, in order to find the larva 

 of A. escheri, since the butterfly is not uncommon there, 

 and this Astragalus seems to be the only probable food that 

 grows in the locality. I found two larvae that I took to 

 be escheri, but, as I failed to rear either, could not be sure, 

 until this year I reared the larva from the egg, and so satis- 

 fied myself that the Berisal larvae were the same as those 

 that were, of course, certainly A. escheri. 



trans, ent. soc. lond. 1915. — parts III, IV. (june) 



