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RouBAUD (E,). Les Conaitions de Nutrition des Anopheles en France 

 (Anopheles maculipennis) et le Role du Betail dans la Prophylaxie 

 du Paludisme.— Jww. Inst. Pasteur, Paris, xxxiv, no. 4, April 1920, 

 pp. 181-228. 



This paper is a sequel to the author's previous work on the infective 

 power of the Anophehues occurring in France [R.A.E., B, vi, 230], 

 which left certain problems concerning malaria in the hypothetical 

 stage. The existence of Anophehnes without malaria,, and the obvious 

 and spontaneous diminution of malaria in many of the previously- 

 infested regions of western Europe and in particular in France, are 

 questions that have required further study. It has been shown 

 [loc. cit.] that the explanation does not lie in any acquisition of immunity 

 on the part of A. maculipennis. It has been a cause of surprise, also, 

 that the expected recrudescences of the disease consequent upon the 

 return of malarial troops from abroad after the War have been insig- 

 nificant. The indications were that A. maculipennis, the most 

 abundant and widespread Anophehne in France, is not highly patho- 

 genic in that country owing to some peculiarity in its biology that 

 restrains its activities with regard to man. 



Former records of the occurrence of this mosquito in France have 

 always been based upon the finding of larvae, and conclusions have 

 been drawn on this basis regarding its pathogenicity in a given region, 

 although its appearance in the adult form may not have been observed 

 nor the habits of flight and nutrition of the adults studied. In this 

 connection it may be mentioned that various Enghsh writers, 

 commenting upon the occurrence of Anophehnes in England, have- 

 remarked that they have never known them to bite, and the same may 

 be said of some of the most heavily infested regions in France. 



It has generally been understood that A. maculipennis shows a 

 decided preference for the blood of animals, the attraction being 

 generally in proportion to the size of the host. It has also been 

 remarked that A. maculipennis, while almost domesticated in Algeria 

 and in the Vendee region in France, rarely approaches man in the 

 neighbourhood of Paris. The explanation has been said to lie in the 

 climate. It is admitted that climate is probably one factor, but 

 malaria has raged, and does still, in various regions of northern 

 Europe w^here the temperature is much lower than that of la Vendee. 



The author has studied at great length the relative value of man 

 and animals in the nutrition of Anophehnes and beheves that this 

 is the key to the problem. His areas of investigation have been the 

 marshes of the Vendee region and the environs of Paris. The 

 topography of the country in la Vendee and the nature of the 

 inhabitants and their buildings are described. The houses are of 

 the most primitive type, low and frequently heavily thatched, and the 

 cattle, the rearing of which is the chief industry, are frequently housed 

 under the same roof. While the marshy region of la Vendee is 

 probably more densely populated with Anophehnes than any other 

 part of the world, and in spite of the conditions of hfe of the inhabitants, 

 malaria is rapidly disappearing throughout the region, and there has 

 been no recrudescence in spite of the return of many malarial subjects 

 from the War. A striking feature of the Anophehne incidence is that 

 on the great marshes, where adults occur with particular density, 



