158 



It is stated that the rat flea [Xenopsylla cheopis] remains infective 

 ior human beings for 30 days or more, and that ordinances in San 

 Francisco are enforcing that all new buildings should be rat-proof in 

 construction. 



LoFTiN (U. C). Mosquitoes found about Gainesville, Fla. Part II. — 

 Traps for Mosquitoes. — Florida Buggist, Gainesville, iii, no. 4, 

 March 1920, pp. 53-59 & 67-71, 3 figs. [Received 14th July 1920.] 



The two previous instalments of this paper have already been noticed 

 IJR.A.E., B. viii, 58, 94]. In this part are recorded the results of experi- 

 ments with mosquito traps consisting of jars or boxes coloured black 

 inside or lined with dark cloth. They should be rather narrow and 

 deep, and should be placed in a well lighted room or porch which is 

 free from dark cupboards, etc. The mosquitos gather in them in 

 the early morning for shelter during the day, and the tops should 

 be closed before the sun shines directly on them. 



The greatest numbers were caught on warm, still nights. Baits did 

 not add to the attractiveness of the traps, and not all species were 

 equally attracted ; Culex fatigans (quinquefasciatus) made up over 98 

 per cent, of the total, Anophelines came next, and only two or three 

 Stegomyia and PsoropJwra were taken. The percentage of C. fatigans 

 is probably higher than is usually found outside the traps. 



These traps are not recommended to rid a place of mosquitos, but 

 if used with judgment will reduce their numbers. Such traps are 

 also useful for collecting specimens for demonstrations, tests or other 

 purposes. They were also used for testing repellants, one trap being 

 treated with a little of the substance, and another about a foot away 

 used as a control. The percentage of efficiency of Bombay Vapor, oil 

 of citronella and oil of tar varied from 92 '8 per cent, to 82 per cent, in 

 the order named. 



Pierce (W. D.). Hutchison (R. H.) & Moscowitz (A.). Government 

 Report on Laundry Machinery. Its Adaptability to various 

 Requirements of Disinfection and Disinsection, — National Laundry 

 Jl., Chicago, Ixxxi, no. 1, 1st January, 1919, pp. 4-14. [Received 

 14th July 1920.] 



The technique employed in obtaining eggs and individuals of 

 Pediculis humanus var. corporis (vestimenti) for these experiments 

 is described, as well as the process of washing and the various 

 observations made on the effects of different temperatures, live steam, 

 insecticidal soap, etc. , on lice. 



The results show that the modern laundry as now adopted for army 

 camps is a thoroughly adequate method of disinfection. A tempera- 

 ture from 140° F. to 158° F., if maintained in a closed vessel for twenty 

 minutes, is sufficient to destroy all pathogenic non-spore-bearing forms 

 of bacteria ; 131° F. will kill lice, and this temperature may be used 

 for woollen materials without causing undue shrinkage. The measures 

 advocated for sterilising woollens are washing for 15 minutes in heavy 

 suds at a temperature of 131° F., followed by 3 rinsings of 3 minutes 

 each at the same temperature ; the garments are then placed in a 

 drying tumbler for 15 minutes at a minimum temperature of 140° F. 



