The air-pump which is described in the present paper was designed in order to replace the rubber double-bellows type of inflator supplied with apparatus for use in the preservation of larvae. In the tropics, the life of articles manufactured from rubber is a comparatively short one, since rubber perishes if frequently handled, or even if stored, in spite of being packed in French chalk. The only rubber article necessary for use with this pump is tubing, which is easily replaceable. In Malaya, it has been found that the double-bellows type of inflator is unsatisfactory, owing to its rapid deterioration.