no 



in horses. Of various remedies tried against screw-worms ( Cochliomyia 

 macellana), gasoline has proved the best, but is not entirely satisfactory. 

 The laboratory work on dips and disinfectants has followed the 

 same general lines as in previous years. 



Abbott (W. S.). Results of Experiments with Miscellaneous Sub- 

 stances against Chicken Lice and the Dog Flea. — U.S. Dept. 

 Agric, Washington, B.C., Bull. 888, 13th October 1920, 15 pp., 

 7 tables. [Received 27th April 1921.] 



As the result of experiments with various substances for the destruc- 

 tion of lice in fowls, oil mixtures were found to be effective when 

 lightly sprayed on the birds, but dipping in the same substance or 

 rubbing it into the feathers proved fatal. As a spray for the roosts 

 and interiors of chicken-houses they proved useless. Oil emulsions 

 were not effective at a greater dilution than 1 to 100. Fumigation 

 with oils, by placing the bird in a sprayed or painted box for at least 

 30 minutes, although effective against the lice, is not advocated owing 

 to the injury caused to the fowls. Mercurial ointment was effective 

 when applied around or just below the vent of the fowl, but vaseline 

 and paraffin were useless applied in the same way. The information 

 in connection with naphthaline has already been noticed [R.A.E., 

 B, viii, 13]. Powders containing nicotine, naphthaline and sulphur 

 were effective when added to the dust bath. Nicotine powders cannot 

 be relied upon at lower strengths than 1-15 or 1-25 per cent., and 

 even then require very careful application. Pyrethrum powder killed 

 all lice within 24 hours, and even when diluted to 5 per cent, it was 

 effective if thoroughly applied, though powdered pyrethrum stems 

 were of no value. 



Against Ctenocephalus cams, Curt, (dog flea) pyrethrum powder 

 alone, or when forming not less than 50 per cent, of the mixture, proved 

 effective. Pure naphthaline was effective when well rubbed into the 

 hair. The various lice powders are effective in proportion to the 

 amount of active ingredients present and the fineness of the powder ; 

 thus 18 per cent, of sassafras oil was effective, but 10 per cent, and 

 less was of no value ; even 4-56 per cent, tobacco powder was not 

 completely effective. Emulsified disinfectants were effective at the 

 rate of 1 to 64 of water when used as sprays and as dips at 1 to 130. 

 Several liquids were effective as fumigants. 



KiNGHORNE (J. W.) & Green (D. M.). Lice, Mites and Cleanliness. 

 — U.S. Dept. Agric, Washington, D.C., Farmers' Bull. 1110, 

 September 1920, 10 pp., 1 fig. [Received 27th April 1921.]. 



Much of the information on parasites of fowls contained in this 

 popular bulletin has been previously noticed[ R.A.E., B, vi, 14]. 



Hall (M. C). Parasites and Parasitic Diseases of Sheep. — U.S. Dept. 

 Agric, Washington, D.C., Farmers' Bull. 1150, December 1920, 

 53 pp., 34 figs. [Received 10th April 1921.] 



This bulletin includes a brief description of the life-histories of and 

 remedial measures for the following insect parasites of sheep : — 

 the lice, Haematopiniis ovillus, Linognathiis pedalis and Trichodectes 

 avis ; the Hippoboscid, Melophagus ovinus ; the mite, Psoroptes 

 communis ovis ; the tick, Ornithodoros megnini ; and the flies, Cochlio- 

 myia macellaria, Phormia regina, Lucilia sericata and Oestrus ovis. 



