Reports to various Correspondents. 73 



The disc (Fig. 10) should be about three inches across with a star- 

 shaped hole in the centre (A) and a slit cut from this to one side (B). 

 The disc is then slipped around the stem and pressed iirmly on to 

 the soil so that the flies cannot crawl beneath. They are thus pre- 

 vented laying their eggs upon the roots, and the young larvpe cannot 

 crawl far, and so die. 



The next best method was found by Professor Slingerland to be 

 injecting bisulphide of carbon into the soil, but I think this would 

 be too costly a process to answer in this country. 



In gardens good has resulted from watering the plants with 



Pig. 10. 



stem of plant passing through card disc 

 lying close on "the ground. 



A, Star-shaped slit so as to allow stem 

 to pass through card ; B, slit to push 

 stem up to A. 



a mixture of carbolic and soft soap, and this was found to be a 

 successful preventive and remedy in Professor Slingerland's experi- 

 ments. 



The mixture is made as follows : 1 lb. hard soap, 1 qt. soft soap 

 dissolved in 1 gallon of boiling water, 1 pt. crude carbolic mixed 

 well together ; dilute with thirty times its bulk of water, and pour 

 with a can and rose around the plants. 



On the Continent a dressing of superphosphate of lime has been 

 found beneficial. Sand soaked in paraffin spread around each plant 

 will also keep the flies off for some little time and so prevent egg- 

 laying. 



