85 



if the adults were fed daily, they could be kept alive for a period of 

 30 to 40 days. 



The scarcity of fleas on a large number of rats obtained at Massa- 

 chusetts was investigated, and it was proved that the fleas, after 

 feeding on their natural host, went into hiding. Rats gather in nests 

 under stable floors in the winter, and it is in such places as these that 

 the life-cycle of the flea continues throughout the year. If the beds 

 of household animals are kept dry and cleaned every few days, there 

 is little chance of the larvae maturing, but in a wet season if the 

 animals are out of doors there is sufficient moisture to complete the 

 life-cycle. Wild fleas removed from their natural host and fed on 

 monkeys, rabbits and guinea-pigs died in about five days, but reared 

 specimens placed on an unnatural host could be kept alive for 

 30-40 days. 



Wallis (T. E.). Moths as Pests in the Pharmacy. — Reprint from 

 Pharmaceutical Jl. & Pharmacist [London]^ 17th December 1921, 

 8 pp., 5 figs. 



Stocks of stored drugs are often infested with such pests as Sitodrepa 

 panicea, Ephestia kiihniella and Tyroglyphid mites. Larvae of 

 Corcyra cephalonica, Staint., are reported to have been found in various 

 substances such as starch, poppy heads, whole and crushed linseed, 

 etc., and in various chemicals. This moth has been frequently found 

 in flour and grain, especially rice. A complete description of this 

 insect and its life-history, as well as that of E. kiihniella, is given 

 [cf. R.A.E., A, i, 292, etc.]. 



The author found large numbers of Borkhausenia pseudospretella, 

 Staint., in valerian root. This moth is a common inhabitant of houses, 

 the larvae feeding on dried plants, skins and seeds. It has also been 

 found in the starch and poppy heads mentioned above. It appears 

 to have been introduced from x^merica about 1840 and prefers cool 

 climates. A full description is given of the larvae and adults. 



The oldest remedial measure against these pests is the apphcation of 

 heat for a sufficient length of time. Experiments have proved that 

 the maintenance of a temperature of 140° F. for a quarter of an hour 

 kills all the eggs, larvae and adults. Larvae of E. kuhniclla are killed 

 by exposure to 120° F. for twenty minutes. When moths attack large 

 bags of commodities, it is necessary to continue the heating until the 

 required temperature is reached in the centre of the bags. In the case 

 of cocoa this can be done by keeping a store heated by air driven over 

 steam-heated pipes for a period of two or three days. A less satis- 

 factory method is fumigation with carbon bisulphide in a closed vessel, 

 but eggs are not killed by this process and only 50 per cent, of the 

 larvae. Formaldehyde, carbon tetrachloride and trichlorethylene 

 have been tried with indifferent success. Sulphur dioxide and hydro- 

 cyanic acid might be useful if they were not objectionable from other 

 points of view. Cold delays the development of the eggs and larvae, 

 but does not kill them. 



MacArthur (W. p.). a Holotrichous Ciliate pathogenic to Theohaldia 

 annulata, Schrank. — //. R. A.M.C., London, xxxviii, no. 2, 

 February 1922, pp. 83-92, 5 figs. 



The ciliate here described as infesting Theobaldia annulata, Schr., 

 taken from a field dyke near Blackpool, is thought by Wenyon to 

 belong to the genus Cyclidium or Pleuronema. 



