in ant-guards. It is necessary that the para-dichlorobenzene be used in powdered form and be well scattered in the guards. About two grams of powdered para-dichlorobenzene, or the same amount of camphor (either lump or powdered) was found very effective in preventing the breeding of yellow fever mosquitoes in flower vases and similar receptacles. It should be repeated every fifteen days, or each time the water is changed. For holy-water urns} especially in churches, lump camphor is recommended.

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... The use of these insecticides should be considered obligatory, and if, after due notice has been given, breeding is found, especially pupre, then the offender should be dealt with severely and to the full extent of the law, particularly so if yellow fever exists in the community. The central station of the sanitary corps should have these insecticides on hand and sell them to the public at, or nearly at cost.