176 



whether or not this will be necessary — the logical method is to destroy 

 the habitat. This may be costly and prolonged, and perhaps pro- 

 hibitive where large numbers of bayous, ponds, cut-offs, etc., exist. 

 If AnopheHnes alone are to be controlled, spraying with a phenol-resin 

 soap emulsion every six days will probably be all that is necessary. 

 This may even be effective against T. titillans, against which, owing 

 to the oxygen produced by the Pistia, ordinary oiling is as ineffective 

 as in the case of Mansonioides africanus [R.A.E., B, v, 57]. 



SWELLENGEEBEL (N. H.) & SWELLENGREBEL DE GrAAF (J. M. H.). 



List of the Anophelines of the Malay Archipelago with Special 

 Reference to Adults and Larvae of new or incompletely described 

 Species or Varieties. — Bull. Entom. Res., London, xi, no. 1, 

 August 1920, pp. 77-92, 11 figs. 



The bulk of the information contained in. this paper has been dealt 

 with elsewhere [R.A.E., B, vi, 53 ; vii, 183 ; viii, 136]. To prevent 

 confusion, Theobald's nomenclature is mainly adhered to. 



In an editorial note it is stated that Anopheles {Myzomyia) flava, 

 Swellengr. [loc. cit. vi, 214] and A. immacvlatus, Theo., are conspecific, 

 the latter name having priority. 



Macdonald (A.). On the Relation of Temperature to Malaria in 

 England.— J^. R.A.M.C., London, xxxv, no. 2, August 1920, 

 pp. 99-119. 



The low average of temperature m England is apparently responsible 

 for the periodical dying out and reappearance of malaria. The 

 presence of carriers and mosquitos may produce little or no mdigenous 

 infection unless a suitable temperature coincides with carrier 

 importation. The temperature directly influences the distribution and 

 incidence of malaria, as a mean temperature of about 59° F. to 60° F. 

 over a period of at least sixteen days is required for the complete 

 development of the plasmodium within the mosquito. It is evident 

 that elevation of temperature alone without extent and continuity is 

 not sufficient for the propagation of the organism. According to the 

 records a brief period suitable for propagation is presented in most 

 years in a certain area of England mainly south of the Humber, but it 

 cannot take place normally under natural conditions in Scotland ; in 

 Ireland the postulated temperature is attained for a brief period of the 

 year in Dublin. 



The natural inference to be drawn from the study of the facts in 

 relation to the occurrences of malaria in 1856-1860 and 1917-1919 is 

 that in England the elevation of temperature necessary for the 

 propagation of malaria does not occur with the certain regularity 

 of extent and continuity required to maintam. endemicity ; and that 

 mdigenous occurrence depends on carrier importation, which _ in 

 suJSicient volume, in the presence of an abnormal extent of high 

 temperature, may engender epidemics and initiate a temporary 

 endemicity, limited in area and years. 



The occurrence of malaria of undoubted indigenous origin in the 

 sprmg months of 1918 is thought to be probably a result of plasmodial 

 development brought about by incubation at the mdoor temperature 

 of occupied and artificially heated rooms. 



