192 



fortnight. Cold manure which has finished fermenting does not 

 attract adult house-flies and does not afford nourishment for their 

 larvae, although larvae of other species have been successfully reared 

 from it. Experiments with creosote oil, which are described, show 

 that 4 gals, to the ton proved effective, but the minimum efiective 

 cjuantity was not determined. Incremental treatment proved superior 

 to surface treatment as the larvae of M. domestica are able to live 

 between the sprayed layer and the extreme heat at the bottom of the 

 heap. A description is given of the technique employed to ascertain 

 the depth at which larvae-infested material may be safely buried and 

 the results show that a depth of 4 ft. is not sufficient to kill the larvae 

 and 90% of them climb to within a foot of the surface prior to pupation. 

 The species used for this experiment was Calliphora erythrocephala. 



Page (G. B.). Experiments with Insectox (a Substance for the 

 Destruction of Flies).— JL R.N.M.S., London, v, no. 4, October 

 1919, pp. 432-436, 1 fig. 



To test the toxic effect of " Insectox " on house-flies air-tight boxes 

 were constructed into which a solution was sprayed at a dilution of 

 1 part Insectox to 20 of water. The experiments described show that 

 a concentration of about 1^ pints per 1,000 cub. ft. is sufficient to kill 

 all insect life in a room exposed to it for about half an hour. Higher 

 concentrations will kill in a shorter time. If the spray is applied 

 direct to the flies and their haunts, a lower concentration should prove 

 effective, but when used as a vapour in the room, flies were apparently 

 moribund after thirty minutes, but recovered after 24 hours exposure 

 to fresh air. Insectox does not damage furniture or ornaments 

 or affect food. In some camps it has been used to spray raw meat 

 in the same way that dilute formalin is sometimes used. Spraying 

 should be commenced early, as soon as the first flies appear, though 

 these methods should only be considered supplementary to the 

 destruction of breeding-places etc. Blow-flies, mosquitos and other 

 small flies are even more susceptible than house-flies to this substance. 



FouLERTON (A. G. R.). The Rat as a Carrier of Diseases transmissible 

 to Man and to other Lower Animals.— JZ. Camp. Path. Therapeut., 

 London, xxxii, no. 3, September 1919, pp. 182-191. 



In the course of this account of the rat as a carrier of transmissible 

 diseases it is stated that among a series of 98 individuals of Mus 

 decmnanus (brown rat) examined in London, 41 were carriers of 

 Trypanosotna lewisi, 3 were carriers of Spirochaeta iderohaemorrhagiae, 

 and one carried both of these parasites. The first-named has never 

 been found as a natural parasite of any other animal than the rat, and 

 shows very little pathogenic activity for other animals ; S. ictero- 

 haetnorrkagiae is the cause of spirochaetal jaundice or Weil's disease ; 

 while S. morsus-miiris, a common parasite of the rat, produces rat-bite 

 fever in man. 



The association of epidemic prevalence of bubonic plague in man 

 with rat plague is well known ; a preliminary outbreak among rats 

 and mice seems to be the invariable precedent to any serious human 

 epidemic. While there h no doubt as to the dissemination of plague 



