152 



Washburn (F. L.). The Malarial Mosquito Harmless in Minnesota. — 



Minnesota Insect Life, St. Anthony Park, iii, no. 10, 1st July 

 1916, p. 3. 



Control measures against Anophelines are being successfully carried 

 out in a localised area in Minnesota. Experiments on the feeding 

 habits of the species present have shown that they do not carry malaria 

 in this State. 



King (W. V.). Experiments on the development of malaria parasites 

 in three American species of Anopheles. — Jl. Experim. Med.,. 

 Baltimore, xxiii, no. 6, 1st June 1916, pp. 703-716, 8 plates. 



Experiments have shown Anopheles punctipennis to be an efficient 

 host of the organisms of tertian and aestivo-autumnal malaria and 

 A. crucians of aestivo-autumnal malaria at least. Information has 

 also been obtained as to the relative susceptibility of these two species; 

 and of A. quadrimaculatus, which has been considered to be the 

 principal species concerned in the transmission of malaria in the 

 United States. 



With A. punctipennis, developmental forms of the exogenous or 

 sporogenic cycle of Plasmodium vivax were demonstrated in six (85 per 

 cent.) of the seven mosquitos dissected, and the development of 

 P. falciparum in four (20 per cent.) of twenty specimens. As these 

 four infections occurred in a series of thirteen specimens fed on one 

 person, the percentage was actually 33. With A. crucians, oocysts or 

 sporozoites or both oocysts and sporozoites of Plasmodium falciparum 

 were found in nine (75 per cent.) of the twelve specimens dissected. 

 No tests were made wdth this series and P. vivax. A. quadrimaculatus 

 was employed as a control species in the experiments and became 

 infected in the following ratio : Eight (66 per cent.) of twelve specimens, 

 with P. vivax, and three (15 per cent.) of nineteen specimens with 

 P. falciparum. 



In determining the relative susceptibility of the three species only 

 those individuals which had been fed upon the same gamete carriers 

 are considered. The number of mosquitos from which the percentages, 

 are computed is too smaU to make the results entirely conclusive, but 

 the indications are that A. punctipennis and A. quadrimacidatits are 

 equally susceptible to infection mth P. vivax, 85 per cent, of each 

 species under the same conditions being positive. With P. falciparum,. 

 A. crucians showed the highest percentage of infection (75 per cent.),. 

 A. punctijjennis second (33 per cent.) and A. qicadrimacidatus third 

 (23 per cent.). 



Beetolio (S.) & Mariani (A.). Contributo sperimentale alio studio 

 della profilassi anti-anofelica. [An experimental contribution to- 

 the study of mosquito-destruction.] — Morgagni, Milan, Ivii, 

 Part 1, no. 7, July 1915, pp. 259-265. [Received 24th July 1916.] 



Owing to the high price of petrol, experiments were made with 

 heavy oil of a density of 0'925, such as is used in Diesel engines, as a 

 lar\'icide in anti-mosquito work. A mixture of nine parts of such oil 

 mth one of petrol proved satisfactory. It should be poured upon the 



