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and these were dealt with by Paris Green. Several fallow rice fields were searched on the left bank of the Shing Mun opposite the site of the Dam but all were found dry. Searches were made in the upper part of B above the access road but no wet fallow rice fields were met with until a considerable distance had been covered.
Above the P.W.D. Dam breeding places were found along stream J and along stream K, and the right bank of the Shing Mun as far as Ho Pui after several searches; first and second time of searching being without result, as if the A. jeyporiensis were retreating up the valley as its breeding places were being dealt with. In December temporary drainage of these additional places was asked for. Towards the end of the year a larval survey was done in the branches of the Shing Mun between Pineapple Pass and the P.W.D. Dam but comparatively few larvae of A. minimus were found in the streams investigated—hence no clearing was asked for.
At the end of October surveys done by the Inspectors in the terraced rice fields along B1 resulted in the finding of A. hyrcanus, A. minimus and A. jeyporiensis. Similar results were obtained about the same time from investigations of the rice fields on the right bank of B opposite stream B3 and above B1. The water was reported to be draining off the plots. In the previous month surveys done in the terraced rice fields adjoining Wo Li Hop had yielded only A. hyrcanus.
Anti-larval measures within the 4" circle were only completed by the end of the year. The Shing Mun stream, B and its branches, and other streams had been cleared and were under oiling. Rice fields adjoining Wo Li Hop, those along stream B1 and those along the right bank of B at the 4" circle had been cleared by the Labour Force of the Engineering staff and treated by the oiling gang. The remaining rice fields between the 3" and 4" circles had been ditched by the oiling gang. Anti-larval measures directed against A. jeyporiensis were in operation along the Shing Mun from P.W.D. Dam to Pineapple Pass and along stream B1 as far as the access road.
The amount of oil used in December was 418 gallons and over 16 miles of streams of varying breadth were under oiling as well as the trenches in the cultivated areas.
During the year works of a permanent nature were done in the rice swamps (indicated by shaded areas) within the 2" circle and along stream Al outside it. Drainage pipes and rubble, surmounted by concrete drains were placed in the narrow rocky bedded streams C, D, and part of E. Permanent work was done on that portion of the ravine which runs from Pineapple Pass to Wo Li Hop and in the breeding places of A.