THE 



GARDENER'S MAGAZINE, 



JUNE, 1837. 



ORIGINAL COMMUNICATIONS. 



Art. I. A Series of Articles on the Insects most injurious to Culti- 

 vators. By J. O. Westwood, F.L.S., Secretary to the Entomolo- 

 gical Society of London. 



No, 4. The Onion Fly. 



Order, Diptera LhmcEus. (Two-winjied flies.) 



Division, Brachocera Macquart. (Having the antennae short, and furnished 



with a bristle above.) 

 Family, MuscidEe Leach. (So named from the Linnsean genus M(isc&.) 

 Subfamily, Anthomyzides Macquart. 

 Genus, Anthomyia Meigen. (So named from two Greek words : anthosy a 



flower, and muia, a fly ; expressive of the attachment of the insects, of which 



it is composed, to plants.) 

 Subgenus, E^glc Rob. Desv. Myod., p. 584. 

 Species, Anthomyia ceparum.* (Scatophaga ceparum Kirby and Spence Intr., 



vol. i. p. 192. note; Anthomyia ceparum Bouche Natiirg., p. 73., Gart. Ins., 



p. 129.) (Cepa, the Latin specific name of the onion; ceparum, gen, plur., 



of the onions.) 



During the summer months, and especially in June and July, 

 the cultivator of onions is annoyed by perceiving that, here and 

 there, in various parts of his beds of this vegetable, the plants 

 appear to be in a dying state, and the leaves fallen on the 

 ground. At first, this is observed in plants which are only just 

 above the surface of the soil, and which are not above the thick- 

 ness of a straw. These soon die, and then others, of a larger 

 size, are observed to decay in a similar manner ; this con- 

 tinues until the middle of July, and even until the onions are 



* Stephens gives this as synonymous with il/usca radicum of Linnaeus and 

 Meigen, Musca decore of Harris, and Anthomyia brassicae of Wiedemann. 

 Macquart gives il/usca radicum of Linnaeus as the E^gle vulgaris of Robineau 

 Desvoidy. The description of ilfusca radicum of Linnaeus will not agree with 

 the onion fly, having four black bands, and feeding upon the roots of i?apha- 

 nus. I should also suppose that it is distinct from Anthomyia brassicae. 

 Bouche has, in fact, described a distinct species of Anthomyia under that 

 name. (Gart. Ins., p. 131.) He has also described A. ceparum and A, radi- 

 cum as distinct. (Xatta-g. des Ins., p. 73. 75.) 



Vol. XHL — No. 87. r 



