123 



€as?s one species succeeds and replaces the other accordmg to the season 

 of the year. In May and June 1918, larvae of A. bifurcatus were 

 abund nt in Perigord in certain pools and ditches while the water was 

 fresh and frequently renewed, but when it became stagnant and warm 

 puring a long spell of summer weather, only larvae of A. macidipennis 

 were found by the month of August. The two species can also exist in 

 adjacent spots, each in its own environment. A striking example of 

 this is seen near Pau where two roads cross at right-angles, one running 

 east and west, the other north and south. A ditch runs along the 

 south side of the one and continues along the east side of the other. 

 In its east-west portion the ditch, shaded from the sun throughout 

 the year by heavy foliage, harbours only A. bifurcatus, while in the 

 north-south portion, upon which the sun shines during the greater part 

 of the day, and which is much less cool, only larvae of A. maculipennis 

 are to be found. 



It seems evident from these observations that although the two 

 species of Anopheles commonly found in France sometimes co-exist 

 in the same water, then normal habitats are decidedly different, their 

 distribution being influenced chiefly by the temperatm'e of the water 

 in which they breed, A. maculipennis being adapted to warm water, 

 and A. bifurcatus to cold. This would explain the earlier development 

 of the latter species m the spring, noticed in various regions, and its 

 extension into mountainous districts such as the Alps and the Pyrenees. 



Sergent (Et.). A Propos de Pyretophorus chaudoyei. — Bull. Soc. Path. 

 Exot, Paris, xii, no. 4, 9th April 1919, pp. 182-184. 



The presence of Anopheles (Pyretophorus) chaudoyei in the Tell Valley 

 of Kabylia was recorded in 1904 by H. Gros on the determination of 

 F. V. Theobald, but doubt is now expressed as to the correctness of 

 this. The species that has been constantly foimd in that region is 

 A. turkhudi (P-. my zomyi fades), which also occurs in the Sahara with 

 A. chaudoyei and A. (P.) sergenfi. The author of the present paper has 

 found A. chaudoyei in the Sahara only, where several investigators 

 have studied it, and its occurrence outside this region requires further 

 confirmation. 



BucHHOLTz (M.). Trench Fever: A Summary from the Literature. — 



U.S. Public Health Repts., Washington, D.C., xxxiv, no. 14, 4th 

 April 1919, pp. 677-681. 



This is a general account of trench fever summarised from literature 

 much of which has been previously dealt mth in this Revietv. 



Marchand (W.). Collecting the Larvae of Tabanus and Chrysops 

 (Dip.). — Entom. News, Philadelphia, Pa., xxx, no. 5, May 1919, 

 pp. 131-137. 



Sortie particulars are given of the habitat of Tabanid larvae, which 

 are chiefly found in the soft mud immediately adjoining water. The 

 best means of collecting them is to place a lump of mud in an ordinary 

 kitchen strainer with a medium-sized mesh ; this should be gently 

 shaken and immersed in water, when the larvae can be easily separated 

 from the mud. Full particulars are given with regard to treatment 

 of larvae to be dispatched for scientific investigation. 



