100 



Seguy (E.). UAedes jugomm, VilL, et les Larves de Moustiques ^ 

 Branchies tr^s dev61oppees. — Bull. Soc. Path. Exot., Paris, xv, 

 no. 1, 11th January 1922, pp. 25-28, 1 fig. 



The highly developed gills discussed in this paper appear to be 

 the characteristic of mosquito larvae that are non-predacious and 

 have a rapid development. They are found in small collections of 

 water that evaporate rapidly or else in water containing a large amount 

 of decomposing matter. 



The mosquitos coming within this group include Aedes argenteus, 

 Poiret, A. alpinns, L. {nigripes, Zett.), A. genictdatus, Oliv., A. 

 echinus, Edw., and A. jugorum, Vill. The last named occurs in the 

 mountains of central and western Europe. Recently A. gallii, Mart., 

 has been considered synonymous with it, but examination of the 

 larva of A. jugortim, a description of which is given, renders the 

 identity of these two species doubtful. 



Sergent (Edm. & Et.), Parrot (L.) & Foley (H.). L'Armature 

 maxillaire des Anopheles macidipennis en Pays paludeen. — 



Bidl. Soc. Path. Exot., Paris, xv, no. 1, 11th January 1922, 



pp. 29-30, 1 fig. 

 In view of Roubaud's statement [R. A.E., B, x, 53] that the number 

 of teeth on the maxillae of mosquitos has a relation to the intensity 

 of malaria, observations have been carried out in Algeria which, how- 

 ever, do not support this theory. Of 1,222 individuals examined, 

 the proportion of AnopheUnes bearing more than 14 " teeth " was 

 46-4 per cent., the general average number of teeth being 14-4. The 

 number of teeth on the two maxillae varied in about half the females 

 of Anopheles macidipennis examined, the number differing by as 

 many as three in some cases. 



Langeron (M). Sur L'Anoph61isme et le Paludisme en France. — 



Bidl. Soc. Path. Exot., Paris, xv, no. 1, 11th January 1922, 

 pp. 30-36. 

 Various theories have been propounded in explanation of the 

 regression of malaria in France, The theory that Anopheles maculi- 

 Pennis has gradually acquired a preference for the blood of animals 

 to that of man is not considered to be sulhciently definitely established. 

 The numbers on which the theory is based are not large enough to 

 eliminate the factor of individual variations. The reason why 

 mosquitos are found in large numbers in stables, etc., is probably 

 because these places afford the necessary dark and hygrometric 

 conditions, whereas human habitations may be too dry and well 

 ventilated ; this, however, does not necessarily mean that they do 

 not attack man. With reference to the attraction for Anophelines 

 attributed to rabbits, no individuals were found where these animals 

 were kept in wooden hutches in a high stable well lighted and ventilated. 

 It is thought that such an adaptation of the dentition as suggested 

 by Roubaud [R.A.E., B, x, 53] is hardly possible in such short a 

 period, the regression having begun before 1897, whereas between 

 1828 and 1860 the conditions were very bad. By supplying an abun- 

 dance of food in the form of animal blood, oviposition and the consequent 

 increase in numbers of mosquitos is stimulated. The regression of 

 malaria is considered to be chiefly due to the systematic draining of 

 deep ponds, the establishment of better roads, the more hygienic 

 manner of housing, as well as an abundance of suitable food including 



