192 



Mosquito-borne Diseases in the Gilbert and Ellice Islands Protectorate. 

 Reports to the Colonial Office. [Received 14th September 1915.] 



The Senior Medical Officer of the Protectorate, Dr. B. C. N. O'Reilly, 

 reports that on a superficial examination of these islands, no species 

 of Anopheles have been found. Species of Stegomyia are, however, 

 abundant and generally distributed. In the Gilbert Islands, there 

 seem to be no endemic mosquito-borne diseases, whereas in the Ellice 

 group numerous cases of elephantiasis are to be found on every island. 

 As the conditions in the Gilbert Islands are everywhere favourable 

 to the establishment and spread of this terrible disease, it is urged that 

 immediate steps should be taken to prevent its introduction, and the 

 Medical Officer of the Ellice Islands recommends that no person should 

 be permitted to travel to or from the Ellice group without a medical 

 certificate that he or she is free from microfilaria. The Resident 

 Commissioner of the Protectorate states that there can be no doubt 

 that elephantiasis was brought into the Ellice Islands as a result of the 

 introduction of native pastors and teachers from Samoa. The London 

 Missionary Society is now beginning to send Samoan pastors to the 

 Southern Gilbert group, and it is pointed out that unless the landing 

 of Samoan and Ellice natives in the Gilberts is immediately controlled, 

 there is serious danger that it may soon prove too late to prevent the 

 establishment of elephantiasis in these islands. 



Cook (F. C), Hutchison (R. H.) & Scales (F. M.). Further 

 Experiments in the Destruction of Fly Larvae in Horse Manure. — 



V. S. Dept. Agric, Washington, B.C., Bull. no. 245, July 20th 

 1915, 22 pp. 



This is a continuation of work on the same subject by these authors 

 [see this Review, Ser. B, ii, pp. 178-179.] The general plan was the 

 same, but a few experiments were also made in concrete pits. In the 

 previous series the best results were obtained by applying the borax 

 in solution daily, but it was thought desirable to advise a restriction 

 of the amount of borax-treated manure to not more than 15 tons to 

 the acre, as the efiect of borax on crops is not yet sufficiently known. 

 The following chemicals were used and the apparent larvicidal effect 

 of each is indicated by the figure which signifies the percentage of the 

 control average. Arsenical dip full strength, 87 ; with an equal 

 volume of water, 89 ; with 3 volumes of water, 74 ; pyridine 1 per 

 cent., 99; para-dichlorobenzene, | lb. in 10 (U.S.) gallons water, 

 93 and 50 ; double this strength, 97 and 98. The effect on the per- 

 centage of water-soluble nitrogen was apparently negligible in all cases. 

 Chloride of lime at f lb., 1 J lb. and 3 lb. to each 8 bushels of manure 

 with 10 (U.S.) gallons water was tried ; the results were negative, 

 the damage to the manure obvious and the cost prohibitive. Epsom 

 salts and lime- sulphur had no apparent larvicidal effect ; sulphuric 

 acid at 1, 2 and 3 per cent, had practically no larvicidal action, but at 

 3 per cent., the total nitrogen of the manure was increased to three or 

 four times that of the control. Aniline was next tried, 1 in 50 gave 

 98 per cent, larvicidal action ; 1 in 100, 97 ; 1 in 20, 80 and in a 

 second case 99. Nitrobenzene, 1-67 lb. with 1/3 lb. fish oil in 10 (U.S.) 

 gals, of water, gave 99 and 100 ; the same mixture diluted with an 

 equal volume of water, 99. In a series of experiments in the open, the 



