78' 



and resulted in mishaps and losses. It is certain, however, that 

 Glossina can be kept and bred in Europe under such conditions as 

 make prolonged experiments possible. If the incubator is small, 

 it is necessary to provide for circulating air through it, otherwise 

 hatching is interfered with and the development of the adults is 

 suspended. G. morsitans being a xerophilous fly, humidity above 60 

 per cent, should be avoided. During the month of June 1914, some 

 of these flies were placed in the Jardin d' Acclimation at Paris. They 

 remained there for over a week at a temperature varying from 

 10°-27° C. [50°-80° F.]. It would therefore appear that the flies can 

 live in France at ordinary summer temperatures, though real acclima- 

 tisation is impossible. 



Carter (H. R.). Impounded Waters : Their Effect on the Prevalence 

 of Malaria — Survey at Blewets Falls. — Public Health Reports, 

 Washington, D.C., xxx, no. 1, 1st January 1915, pp. 15-33, 

 1 sketch map. 

 This survey was undertaken in order to determine the relations of 

 the pond of the power plant at Blewetts Falls, N.C., to the breeding 

 of Anopheles. In order to have an idea of the breeding places in the 

 normal river valley before the dam was built, a survey was made of 

 two sections of the valley — each a little less than a mile long — one 

 beginning a mile above a backwater and nmning about a mile up 

 stream, and the other beginning one-half mile below the dam and 

 running about a mile down stream. Both of these were surveyed 

 physically and biologically. Below the dam. Anopheles were breeding 

 freely over a wide extent of marshy flat used as a pasture, but were 

 scarcer above the pond. The creeks emptying into the pond were 

 found to be breeding Anopheles, and as the small streams which emptied 

 into the pond some distance from the dam practically all contained 

 mosquito larvae in that portion of their beds which would have been 

 submerged had the stream emptied into the river closer to the dam, 

 it is probable that those which did so empty into the river close to 

 the dam were formerly breeding places, though now covered by the 

 pond. The conclusion reached is that the valley now occupied by 

 this pond formerly bred Anopheles over a large area . A survey of 

 the pond was next undertaken. In this were included the backwater 

 of creeks and their branches, the pools left by the subsidence of the 

 pond, the pools and marshes which are not drained on account of the 

 existence of the pond, the side pools of creeks and branches filled because 

 they were backed up by the pond and left by its subsidence, and, in 

 short, every collection of water due to the existence of the pond either 

 directly or indirectly. The result aimed at was to estimate the total 

 effect of the pond in the production of collections of water, and hence 

 of Anopheles. The plant at the dam is partially shut down from 

 Saturday noon to Monday morning, and also partially every night. 

 This produces a regular change in the level of the pond, independent 

 of the rise of the river which supplies it. Besides the mosquito larvae, 

 the animal life foimd in the pond included fish, water-boatmen, Gyrinid 

 beetles, a water- spider, and the larvae of the mosquito Psorophora. The 

 two last-named were not common enough to be of probable importance 

 as preying on Anopheles larvae, though the others exercised some 

 control. The naked banks caused " floatage " (the small pieces of 



