10 THE ENTOMOLOGIST. 



mostly destroj'ed by grub." From Cheshire a correspondent, 

 writing on August 7th, reports that " Mangold is again suffering 

 from the maggot in the leaf.'' Mr. T. Duckham, M.P., says of 

 Herefordshire, "Mangold injured seriously by white grub in the 

 leaf." The most entomological report hails from North Wilts. 

 In the number for July 19th, W. P. J. A. writes, "Early sown 

 mangolds have grown well, but are much injured by the maggot 

 in the leaves, recently mentioned by 3'our correspondents ; nearly 

 every plant is attacked, and some of the leaves appear scorched 

 and shrivelled. I see several other large-leaved plants are 

 similarly affected, as fat-hen, burdock, and docks. The latter 

 plant has been liable to such attacks generally ; however, I have 

 noticed dock leaves affected in the same manner for thirty-five 

 to forty years. Last year parsnips and celery were destroyed by 

 this pest."' This is enough to show the general distribution of 

 the mangold-fly, and the noticeable injury it has everywhere 

 caused. Now to the destructive itself. 



The eggs are laid in little scattered heaps on the under side 

 of the mangold leaves, between the ribs, generally about the end 

 of May or early in June, and again in July or August. These are 

 elliptical in form and snowy white in colour, but 

 with a strong glass they show a honeycomb-like, 

 hexagonal pattern, as seen in the figure, which is 

 copied from Farsky. As is very general in Dip- 

 tera these eggs are attached together by means 

 of a gummy substance, more often longitudinally, 

 but not always ; this viscous nature also attaches them to the 

 leaf. Farsky found from four to eleven eggs in a batch, and as 

 many as four batches on a leaf; but this is probably exceptional. 

 Each egg is from ^ to f of a millimetre long, by about | mm. 

 broad. 



As soon as hatched the young maggot bores through the lower 

 cuticle of the leaf, and commences feeding on the pulp. It now 

 feeds very energetically, and grows accordingly. The whole 

 parenchyma of the leaf is often completely eaten, nothing but the 

 thick midrib stopping the course of the larva. The leaf then 

 presents a very bladdery or blotched and bleached appearance ; 

 it speedily withers up and dies, but does not drop oft'. The larvae 

 sometimes are found singly, but more often two or three feed in 

 the same blotch, and where there were as many as eleven eggs 



