CAEBON BISULPHIDE. 69 



Hypera polygoni. — The larvae of this weevil attaches itself to the 

 stem of the poppy and forms a disease of that plant. Sorauer advises 

 the application to the stems of a soap emulsion, containing a little 

 carbon disulphide. 



Saperda Carcharias, L. (large poplar longicorn). — It is recom- 

 mended to inject carbon disulphide into the burrows occupied by the 

 larvae and to stop the holes at the base of the trunk with mastic. The 

 larvae of Lucanus cerinis (Cerf volant) in old oaks are destroyed in the 

 same way, as well as numerous capricorns, of which the following are 

 the principal : — 



Ceramhyx heros, F. (great Capricorn injurious to oaks) ; Cerambyx 

 dilatahis, Eatzeb. (maple Capricorn) ; Galeruca calmariensis (elm 

 galeruca). — The larvae pass through their first stage of metamorphosis 

 underground, in the neighbourhood of the trees, in the end of July, 

 and the perfect insects pass the winter in the same spot. It is 

 therefore at these two periods that it is possible to destroy them by 

 injecting into the soil 50 grammes of carbon disulphide per square 

 metre, spread all round the stock, in eight holes only 20 centimetres 

 (7'8 inches) deep. Watering of the soil before the application facilitates 

 the action of the sulphide on these insects lodged in the upper part 

 of the soil. Carbon disulphide has also been employed with equal 

 success against : — 



Gryllotalpa vulgaris (Courtiliere, Taupe, Grillon), (mole-cricket, 

 churr-worm, eve churr, or earth crab). — Soils are rendered immune 

 for ten years by carbon disulphide on condition, however, that there 

 is co-operation between the different proprietors of the neighbouring 

 cultivated fields. The total expense per hectare rises to 180-200 

 francs for ten years, say 20 francs (16s.) per hectare per annum (say 

 6s. 4"8d. per acre), which is trifling. The sulphide is employed at the 

 rate of 40 grammes per square metre if the soil is compact, and at 

 the rate of 30 grammes only when the soil is light. The latter type 

 of soil is always preferred by the insect. In Italy, near Nola, where 

 mole-crickets have caused serious ravages for twenty years, carbon 

 disulphide has been used over a great area, and has been recognized 

 as an infallible insecticide. Janin advises gardeners to use capsules 

 containing 3 grammes of sulphide, and to deposit them here and there 

 in their burrows, and afterwards to water the soil. It is preferable to 

 make injections in the burrows, by making numerous holes, in the 

 spring. 



Tipula oleracea (daddy longlegs), Tipula pratensis (the spotted 

 garden gnat). — Marechal got good results by injecting carbon disul- 

 phide. To free a lawn from the larvae of these insects 20 grammes of 

 carbon disulphide should be spread in three holes per square metre, 

 the grass trenched after a few days and sown with the seed. There 

 may be destroyed in the same way the Tijnda crocata and the Tipula 

 melanocera, injurious to young plantations of Abies balsamea and of 

 Pinus sylvestris. 



Spilographa cerasi, F. (cherry spilograph, cherry fly). — Besides 

 the process which consists in collecting all the wormy cherries, 

 Taschenberg recommends as an excellent means of destruction, to bore 



