498 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. '84 



I had several conversations with men who had served through the summer 

 campaign, and made a few notes of facts which they told me, as follows : 



In late August or about the first of September, a committee was appointed 

 by Doctor White, consisting of Prof. Rubert Boyce of the Liverpool School of 

 Tropical Medicine, Dr. Quitman Kohnke, the Health Officer of New Orleans, 

 Doctors Currie and Perkins of the Public Health and Marine-Hospital Service, 

 and Dr. H. A, Veazie of New Orleans. This committee conducted numerous 

 experiments, and it is hoped that a report will be published. 



Water closet tanks were found to be abundant breeding places of the yellow 

 fever mosquito, and Doctor White suggests that it will be an easy matter to 

 cover these tanks with wire gauze, and tliat such an arrangement should 

 be enforced. 



They have been found to breed in the accumulation of water in the drain- 

 traps of stationary washstands. 



The roof-gutters of New Orleans were especially noticed on a number of 

 occasions, where they sagged, to contain large numbers of breeding mosquitoes. 



Another interesting place where they were found breeding was in the urns in 

 the cemeteries. 



Doctor Richardson stated that at Laredo in 1903 they were found breeding 

 in the lye barrels where ashes were mixed with water for the purpose of 

 making lye. 



Doctor Richardson also noticed them in the same year in the holy-water fonts 

 at Laredo. In New Orleans they were also noticed in the holy-water fonts. 

 Here, however, they sui)stituted wet sponges. 



It may be stated by the way that a man describing himself as a " practical 

 Catholic " has invented, in Boston, a covered holy-water font for the purpose of 

 preventing the spread of disease. 



In New Orleans it is the custom to keep wine cool by placing it in the pools 

 of water accumulating under the water tanks. In these pools the yellow fever 

 mosquito was found to breed extensively. 



In some houses in the low quarter of the city water was found to accumulate 

 under the houses in places where it could not well be reached. In these saturated 

 solutions of copper sulphate were thrown with a hose as a spray, and proved 

 reasonably efficacious. 



THE PRACTICAL USE OF PREDATORY AND PARASITIC INSECTS 

 From very early times, writers have pointed out that some insects 

 feed upon others, and of course this was early a matter of common 

 observation among farmers, gardeners, and fruit-growers. Enlight- 

 ened gardeners, for example, very many years ago realized that the 

 little black and red beetles known as ladybirds were their friends, 

 and in early works on gardening it was advised that these little 

 beetles be placed upon plants, such as rose bushes, that were infested 

 by plant lice. 



The study of parasitic and predatory insects is old. Silvestri has 

 pointed out that Aldrovandi in 1602 was the first to notice the exit 

 of the larvae of Apantdes glomcratus from the common cabbage 

 caterpillar, and that Vallisnieri (1661-1730) was apparently the first 



