73 
Reports to various Correspondents. 
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 firmly 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 larvae 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 
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. 
Fig. 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. 
