64 



Females of Anopheles are known to bite occasionally in winter and 

 therefore usually hibernate in stables where blood can be obtained, 

 while species of Aedes, which hibernate in cellars, seem not to bite 

 in winter even if brought into a heated room. The absence of 

 thermotropism would therefore be only an adaptation to the 

 conditions of hibernation, during which no blood food is taken, and 

 it is quite possible that A. sylvestris will be found to be thermotropic 

 during the biting season, unless in this genus other tropisms are 

 involved. 



PiCKELS (A.). Nigeria [Northern Provinces) Annual Medical & 

 Sanitary Report for the Year ending 31st December 1917, Lagos, 

 pp. 107-165. [Received 17th February 1919.] 



Malaria continues to attack large numbers of the younger and less 

 experienced members of the European community in the Nigerian 

 Northern Provinces though preventive measures against mosquitos are 

 general. An effective method of dealing with domestic mosquitos, 

 especially in mud huts with thatched roofs, is to drill about a dozen 

 holes in the bottom of a native pot, mount the pot on three stones, 

 hne the bottom ^vith stones and above the stones make a good 

 charcoal fire. Broken native tobacco is piled up on the fire and on 

 the top is laid a paper bag full of black, native pepper. This makes 

 a good fumigant, and must be left in the hut, which has previously 

 been made as air-tight as possible, for 24 hours. Upon opening the 

 hut, all insects, including mosquitos, flies, cockroaches, earwigs, etc., 

 have fallen to the floor, dead or stupefied, and can be swept up 

 and burnt. About 1,800 cubic ft. can be treated at once in this way. 



An outbreak of yellow fever occurred in one locality; nine 

 Europeans contracted the disease, but no case in a native was 

 observed. This is the first time the disease has assumed an epidemic 

 form in the Northern Provinces. 



Sleeping sickness is reported from time to time, the incidence 

 probably being twice as great among native as among European 

 communities. The precautions against Glossina are continually 

 practised and are only limited by the means available. Instances of 

 tsetse-fly being active by night are being reported with increasing 

 frequency ; this is perhaps owing to the more careful observation of 

 the insect's habits. Every year the belief in the efficacy of broad, 

 cleared roads as a preventive measure against these flies is being 

 confirmed, and this is a measure that is bound to progress, for every 

 indication points to the widely-spread exploitation of the country's 

 resources after the War. 



Parsons (Capt. A. C.) & Brook (Lce.-Corpl. G. R.). The Mosquito 

 Problem in Britain : Suggestions for a Winter Campaign against the 

 Important Mosquitos, with Notes on Insecticides. — Jl. R.A.M.C., 



London, xxxii, January 1919, pp. 1-23. 



As, the most prevalent of the malaria-carrying mosquitos in England, 

 namely, Anopheles inacttlipennis, and the most common Culicine, 

 Culex pipiens, both pass the winter as adults, the females generally 

 hibernating in cellars, cow- byres, pigsty s, stables and outhouses, it is 

 suggested that the winter would probably be the best time for dealing 



