122 



It was found that G. mellonella may easily be infected by injecting 

 an emulsion of the cholera vibrio, but infection is not produced by 

 ingestion. The course of the disease produced depends on the virulence 

 of the culture injected, the same results being obtained with dysentery 

 bacilli of varying virulence. Immunity is easily acquired in from three 

 to twenty-four hours, according to the virulence of the culture, the more 

 virulent strains requiring the longer time. After immunity all cellular 

 reactions become more marked and rapid, phagocytosis, the formation 

 of giant cells, etc., all occurring more quickly. Immunity is the result 

 of complicated involuntary reactions of various cells, these reactions 

 being specific for each micro-organism. 



Lake (G. C.) &: Francis (E.). Tularaemia Francis 1921, VII. Six Cases 

 oJ Tularaemia occurring in Laboratory Workers.^Pzf&. Health 

 Repts., Washington, D.C., xxxvii, no. 8, 24th February 1922, 

 pp. 392-413. 



The entire personnel of the laboratory that has been investigating 

 tularaemia in rodents, caused by Bacterium tularense, under the United 

 States Public Health Service, has become infected with a fever lasting 

 about three weeks. The diagnosis in each of these cases rests upon the 

 occurrence of a febrile period lasting about three weeks, positive serum 

 reactions for agglutination and complement fixation to antigens 

 composed of B. tularense, and the absence of febrile attacks in 100 other 

 persons in the laboratory coming in casual contact with infected rodents. 

 The skin of the hands must be considered as a possible means of entry 

 of the infection in the laboratory workers, even in the absence of a local 

 lesion or lymphadenitis. 



Unrecognised cases of tularaemia probably occur in the known foci of 

 infection in the United States, and routine serological tests would 

 probably not only detect cases in known foci of infection, but would 

 also reveal unknown foci. Light might also be thrown upon the 

 etiology of some fevers of undetermined origin. 



Wells (R. W.). Bishop (F. C.) & Laake (E. W.). U.S. Bur. Ent. 

 Derris as a promising Insecticide. — //. Econ. Ent., Geneva, N. Y., 

 XV, no. 1, February 1922, pp. 90-95. 



That derris promises to be of value both as a contact and a stomach 

 poison has already been pointed out [R.A.E., A, vii, 496]. In this 

 paper, experiments are described in which powdered roots of Degiielia 

 {Derris) elliptica were used against Mallophaga, including Trichodectes 

 seal arts on cattle ; Anoplura, including Linognathus vituH, L., and 

 Solenopotes capillatus. End., on cattle, and L. setosus, Olf., on dogs; 

 and the fleas. Ctenocephalus canis, Curtis, and C. felis, Bch., on dogs 

 and cats, and Echidnophaga gallinacea, Westw., on dogs. 



The minimum dose required per animal to kill all fleas on various 

 breeds of dogs was found to be • 87 gm. of a mixture of equal parts 

 of derris and maize starch. One treatment proved to be sufficient 

 to kill all stages of Anoplura on cattle and dogs ; against Mallophaga 

 on chickens and cattle it also proved very efficient, but not quite as 

 effective on cattle as sodium fluoride. An ointment consisting of one 

 part derris and two parts vaseline was applied to the apertures due 

 to the presence of larvae of Hypoderma lineatum in the backs of cattle. 

 Five days after application all larvae were killed, and the condition 



