195 



as the weather gets colder, bed-coverings, in which hce thrive and 

 multiply, are brought into use. Apparently there is a distinct con- 

 nection between the prevalence of the disease and personal habits, 

 though all classes may sufEer. In the upper classes cases generally 

 occur in children, who probably become infected with lice while at 

 play. Lice can always be found in infected households and there 

 appears to be a distinct relation between the numbers of these para- 

 sites and the severity of the infection. The way in which the disease 

 is confined to families is most marked. All the families in the houses 

 surrounding a certain courtyard may be infected, while the dwellers 

 in a neighbouring one, separated only by a partition wall, will be 

 entirely free. The source of infection is almost always traceable, and 

 there is generally a history of a visit of a few days to a village where 

 there have been cases of fevec and the visitor on his return tails sick, 

 the disease then spreading to his family. In infected villages there are 

 no biting insects other than lice sufficiently common to account for 

 the great prevalence of the disease. Despite diligent search, the 

 author failed in a large number of cases to find a single bug and he 

 suggests that the reason is that the beds are placed daily in the sun 

 and are used as chairs in the courtyards. Ticks and spiders found in 

 the houses were examined for spirochaetes with negative results. 

 The author states that his experiments show that the bites of infected 

 lice are innocuous and he has himself been bitten on three occasions 

 without result, but direct infection may easily take place through 

 the finger tip in the act of crushing the lice between the nails. 



Among the preventive measures suggested is a general crusade 

 against lice, and this is considered very feasible, because the headmen 

 of villages are put to great inconvenience when their village is infected 

 owing to the immediate scarcity of labour. Lice are easily killed 

 by placing infested blankets or cotton quilts out in the sun, death 

 occurring in a few hours. Many of the fatal cases are apparently due 

 to the local belief that sick persons should not be fed. 



Bentley (C. a.). Note on Experiments to determine the Reaction o{ 

 Mosquitos to Artificial Light. — Proc. Third All-India Sanitary 

 Conf., Luchiow, January 19th-27th 1914, v, pp. 9-11, Suppmt. 

 to Ind. Jl. Med. Research. [Received 6th November 1914.] 



A brief account is given of experiments on the attraction which 

 artificial light has for mosquitos, the general result obtained being 

 that the insects are responsive to light from artificial sources and that 

 therefore its use serves to attract them to the immediate vicinity of 

 man. This possibly affords an explanation of the fact observed by 

 Fry and others in Bengal, that in some malarious districts the growth 

 of very dense vegetation in villages is associated with a much lower 

 spleen index than that found in villages possessing a more moderate 

 amount of vegetation ; it also explains the view held by King that 

 a screen of trees shuts out malaria and mosquitos. It is suggested 

 that the brilliantly lit bungalows of Europeans often serve as a means 

 of attracting Anopheles from a very wide area, and the fact that 

 mosquitos are thus attracted should be remembered in constructing 

 mosquito-proof houses, especially in known malarious locaHties. 



