i88i.] PARAFFIN-OIL A CURE FOR MEALY-BUG. 89 



also, in a former paper on the Ixora, advising the use of cold water, 

 applied with force from syringe or water-engine, as a means of exter- 

 minating mealy-bug from the plants. Such practices are now quite un- 

 necessary since the discovery of the paraffin-oil cure. Plants infested 

 with mealy-bug may be simply and safely cleansed by the judicious 

 application of paraffin. My own experience in connection with its 

 use has been mainly amongst indoor plants ; and in order to divest the 

 plants of the enemy, the course of procedure is as follows : First of all, 

 secure a shallow wooden tray or tub, into which put two gallons of 

 water, then add two wine - glassfuls of paraffin, which thoroughly 

 mix with the syringe ; then the liquid is ready to be applied. The 

 operation is generally performed in the house where the plants grow, 

 as this prevents the possibility of the enemy being carried to any other 

 place where it would be likely to come in contact with other plants not 

 affected. The water and paraffin being well mixed with the smart use 

 of the syringe until the mixture assumes a slightly whitish appearance, 

 the infested plants may then be taken from their positions in turn, one 

 man holding the plant over the tray or tub, while another applies the 

 mixture with the syringe. It is necessary to syringe every alternate 

 syringeful sharply into the tray, to keep the water and oil well mixed, 

 otherwise the cure will be worse than the disease. Plants of Ixoras, 

 Crotons, Gardenias, Eucharis, Stephanotis, Clerodendrons, Hoyas, 

 and others, have been thoroughly divested of the enemy by this means. 

 Dipladenias are more easily damaged by the oil than the foregoing 

 plants which I have mentioned, and I would advise half the quantity 

 of paraffin for them — viz., one wine-glassful to two gallons of water. 

 Dipladenias are also among the worst of stove subjects to cleanse 

 effectively, as dozens of the enemy will lodge securely under the loose 

 bark on the main stems while the deadly operation is being proceeded 

 with. To overcome this difficulty an extra strong dose should be pre- 

 pared and applied with a sponge — sponging carefully every part of the 

 stem where they would be likely to harbour. The Poinsettia is also 

 another plant that ought to be treated similarly to the Dipladenia. I 

 have also used this light mixture for Cucumbers with perfect success, 

 syringing them where they stood growing in beds in a Cucumber- 

 house. The dripping of the oil from the plants on to the bed did not 

 seem in any way to injure the roots of the Cucumbers; indeed, to con- 

 vince any reader of this, I may mention that one large plant of Croton 

 angustifolius was watered at the root with one wine - glassful of oil 

 well mixed in 1^ gallon of water, to exterminate worms, and another 

 plant of Alocasia macrorhiza received a similar dose for the same pur- 

 pose. The experiment was performed in spring. Both plants did 

 remarkably well the following summer, the Allocasia throwing up pro- 

 digious, beautifully variegated leaves : the Croton also grew well, — 

 the dose in no way affecting either the growth or colouring of these 

 plants. Dipping the plants overhead in the liquid is a dangerous 



