44 Belladonna Leaf- Miner 



1. Introduction. 



The first record that we have of Pegomyia hyoscyami Panz. dates 

 back over a century when Panzer described it in 1809 from Central 

 Europe, including it in the genus Musca. Previous to this however 

 Reaumur in the year 1737 gave an admirable account of the behaviour 

 of the larva, with a few structural details, which he found mining the 

 leaves of henbane, Hyoscyamus niger. He figured the larva, and drew 

 attention to the resemblance that exists between it and the larva which 

 he found mining in the leaves of the beet. No mention is made of the 

 adult insect, a fact which Vallot noted in 1849, in dealing with the 

 " Pegomyie de la jusquiame." This latter also observes that Reaumur's 

 expectation that the larvae which mine the leaves of the pear would 

 be identical with those found in the leaves of henbane failed in its reali- 

 sation, for he showed that the adult insects belong to two different genera 

 of Diptera. 



This fly has been treated of by various authors and much confusion 

 exists in the literature on the species, due to the fact that it has a fairly 

 large number of food plants. This has led many authors astray, so that 

 it has been described several times under various names, and in one or 

 two cases the same author has described it under two different specific 

 names. There does indeed seem to exist a distinct variety, namely that 

 which attacks beet and mangolds, described first by Curtis in 1847. 

 Much damage is done periodically to these crops both in this country 

 and in Europe as well as in America. In fact so much so is this the case 

 that it often constitutes itself a serious menace to their successful culti- 

 vation. In England and in Ireland Curtis and Ormerod recorded damage 

 from various parts of the country, and Carpenter more recently lias 

 notified its ravages from Ireland, as also Farsky on the continent and 

 Chittenden in America. 



It was with the idea of verifying some points in the life-history of 

 the species and also of unravelling the tangled skein of the nomenclature 

 that I took the opportunity presented to me of rearing the species on 

 Atropa belladonna, the Deadly Nightshade, which I believe to be the 

 first record of its being l)ip{l fiom tiiis plant. By moans of facilities 

 offered at Holmes Chapel Agricultural College Earin, I was enai)led to 

 compare it with the var. hcfac which was obtained from the mangold 

 crop tlieie, and 1 am also indebted to Professor Carpenter of the Royal 

 C-ollege of Science foi- Ireland for several specimens kindly given to me. 

 In addition I took the opportunity of nuiking a comparison of the larval 



