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SUMMARY:The intestines of clothes moth larvae, Tineola bisselliella, examined usually contained very few micro-organisms; this may be related to the high pH values of the intestinal contents. It was concluded that bacteria play no part in the digestion of wool by these larvae.It was shown by Linderstram-Lang & Duspiva (1936) and by Waterhouse (1952) that the mid-gut of the clothes moth larva, Tineola bisselliella, has a reduction potential of c. -250 mV. at pH values near 10. These reducing conditions, thought to assist the digestion of keratin, might result from the metabolic processes of micro-organisms within the intestine. We therefore examined the intestinal microflora of the moth larvae. METHODSLarvae were obtained from laboratory cultures growing on unsterilized lactic casein powder (90-mesh) containing 10% dried yeast powder, and from naturally occurring colonies on greasy wool. Laboratory cultures on wool were obtained by transference of larvae or eggs from casein medium to greasy wool and incubation a t the optimal temperature of 28". Larval intestines were withdrawn aseptically after circular incision of the skin near the head and amputation of the tail tip.Emulsions of four to six intestines in 0.05 ml. peptone water were equally distributed on six plates of nutrient agar containing 1 yo (w/v) glucose and 0.5 yo (w/v) yeast extract adjusted to pH values 7.5, 8.5 and 9.5. Plates were incubated aerobically and anaerobically a t 28'.

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The efficiencies of bactericides in destroying bacteria on woollen blanket were investigated on a laboratory scale. The bactericides were not effective when tested with new blanket; this low efficiency was found to be related to the rapid adsorption of the bactericides by the wool. Pretreatment of the wool with concentrated solutions of bactericides depressed the rate of depletion of the bactericides from subsequent washing liquors with bactericides at customary concentrations, and led to more satisfactory rates of kill (inactivation factors about 106).The test organisms,Staphylococcus aureusandEscherichia coli, were applied to the blanket as a powder, and the relative densities of bacteria on the blanket were determined using a procedure based on maceration of the fabric. The bactericides, 4-chloro-3, 5-xylenol (P.C.M.X.), cetyl trimethyl ammonium bromide (C.T.A.B.) and bis-(4-chlorophenyl diguanido)-hexane diacetate (chlorhexidine diacetate) were tested in the presence of appropriate detergents.Cultures were kindly supplied by Dr Hildred Butler of the Royal Women's Hospital, Melbourne.