214 



must be renewed every two or three days. It is not necessary to 

 attempt to protect the entire animal but only those parts in- 

 accessible to its head and tail. The United States Bureau of 

 Entomology have extensively tried fish oil alone; fish oil mixed 

 with sulphur and carbolic acid; kerosene emulsion alone or with 

 tobacco water added, and in addition resin and oil of tar. In 

 certain parts of Texas the use of cattle dipping-vats, with suitable 

 insecticides, has been recommended, with very great success. The 

 author says that two distinguished German chemists have sug- 

 gested that potassium tellurate taken internally repels mosquitos, 

 flies and ticks. This was administered in the drinking w^ater of 

 9 horses and 1 cow ; 10 grams were used for each animal in doses 

 of 1-5 grams, but only negative results were obtained. Experi- 

 ments with oleum lauri as an insectifuge are said to have given 

 positive results. 



Hamer (W. H.). Seasonal Prevalence of Fleas. — A7in. Rept. of 

 the L.C.C. for 1912, London, 1913, p. 64, 1 chart. 



From the beginning of 1909 an attempt has been made to obtain 

 a detailed record of the seasonal prevalence of fleas in London 

 and the results are given for the years 1909, 1910, and 1911 in a 

 chart published in the Annual Report of the Council, Public 

 Health, vol. iii, 1911, page 62. 



The enquiry until 1911 had been limited to the observation of 

 flea prevalence in common lodging-houses, but towards the end of 

 1911 additional information was obtained on the examination of 

 elementary school children by counting the numbers flea-marked. 

 The Medical Officer of Health remarks that the number of flea- 

 marked children found in the last four months of 1912 agrees 

 very closely with the curve obtained from common lodging-houses. 

 The maximum appears to be reached in August and September 

 and the minimum in January. 



Insect Notes from the Seychelles. — Ann. Rept. on Agric. and Croion 

 Lands for the year 1912, Victoria, Seychelles, 1913, p. IT. 



In connection with mosquito larvae (mostly Stegomyia) an 

 experiment was made at Government House with the local small 

 fish called Goujon {Haplochilus j^layfuiri), which differs little in 

 habits from the celebrated " Millions " fish of Barbados (Girar- 

 dinus poeciloides). In a small basin where mosquito larvae were 

 teeming 50 goujons were introduced one afternoon, and the next 

 morning not a single larva was found and none has ever been 

 found since, while the small fish, after two months, started to 

 multiply considerably. This experiment may serve to show that 

 there is in the Seychelles an effective enemy of mosquitos, the fish 

 being able to live in the smallest pond. 



Laws (H. E.). How Ticks are Killed when Cattle are Dipped. — 



Agric. Jl. of the Union of S. Africa, Pretoria, vi, no. 1, 

 July 1913, pp. 49-54. 



In view of the importance of knowing exactly in what way ticks 

 on cattle are killed during dipping, further experiments have 



