io8 First Report on Economic Zoology. 



bulb as you describe. Those I have kept attacked as many as ten 

 bulbs before becoming mature. When one bulb is destroyed they 

 crawl through the soil and enter the next one at its base. The grubs 

 seem to reach maturity during November, but some kept under 

 observation Lived until January. When full fed they form a cell in 

 the earth near the last bulb attacked and line this cell with silk, 

 forming a perceptible cocoon. The puparium is dark brown, oval in 

 form, and has two projecting processes in front. 



It is probable that this pest is constantly being imported from 

 the Continent. 



It is very desirable to lift all bulbs in a bed that is invaded 

 before October ends, even if it is not the year for theu^ removal. All 

 bulbs should be examined and any showing decay destroyed, or the 

 fly will go on increasing and may do endless harm. Where beds 

 have been invaded and the bulljs lifted, the ground should be deeply 

 dug and the top spit buried so as to prevent the flies emerging next 

 year. Mr. Leney informs me that on lifting the bulbs to ha^^e 

 them examined and to kill the larvae no more than two full-grown 

 larvse occurred in each bulb, but more frequently only one in a bulb ; 

 when, however, the larvre are in a younger stage and about half the 

 size of those sent (fully mature) he invariably found from seven to 

 eight in a single bulb. 



The Marguerite Fly and its Destruction. 



Specimens of Marguerite leaves tunnelled and generally damaged 

 were received from Great Staughton, near St. Neots, on the 4th of 

 June. The following reply was sent in answer to a request for 

 information in regard to destroying the culprits : — 



The white daisies that are attacked are being tunnelled by the httle 

 grubs of a small fly, the Marguerite Fly {Napomyza lateralis, Fall.). The 

 only thing one can do is to pick off all the diseased leaves, and if they 

 are"^very bad destroy (burn) the whole plant. There is no remedy, and if 

 left alone they go on spreading very rapidly. When the plants are young 

 spraying with paraffin emulsion will keep the fly away, but when it has 

 once laid its eggs on the leaf you can do nothing for it. 



The Carrot Fly {Psila rosce, Fabr.) and Aphides 



on Carrots. 



The Carrot Fly {Psila rosm) was veiy destructive during the 

 summer of 1902. One correspondent, Mr. Hammond, \\Titing from 

 Canterbmy, states as follows : " I have since looked at my neigh- 



