328 



in America and on the Continent, but not, apparently, in Britain. 

 Parallel instances of the appearance of sexuales in summer are rare, 

 but further study may prove it to be more frequent than has been 

 supposed, and the disappearance of some forms from a food-plant, 

 which has been attributed to migration to a difierent one, may be 

 simply the normal cycle after production of fertilised ova. Descrip- 

 tions of the male and oviparous female forms of A. saliceti are given. 



Paillot (A.). Sur une Reaction des Micronucleocytes des Chenilles 

 d'Euproctis chrysorrhea, contamin6es par le Bacillus melolonthae 

 liquefaciens \. — C.R. Soc. Biol., Paris, Ixxxiii, no. 15, 1st May 

 1920, pp.' 615-617. 



If a fresh culture of Bacillus melolonthae liquefaciens \ is inoculated 

 into the body cavity of larvae of Nygmia jphaeorrhoea {Euproctis chryso- 

 rrhoea), the micronucleocytes in the blood exhibit a marked protoplasmic 

 reaction, which most frequently begins within an hour of the inoculation. 



The direct cause of the reaction is a toxin secreted by the Bacillus. 

 If a drop of a concentrated emulsion of microbe culture is inoculated 

 into the body cavity of the caterpillars the reaction occurs, but is 

 neither so intense nor so complete as when hving bacilli are used ; the 

 majority of the micronucleocytes resist the action of the toxin and more 

 or less quickly regain their normal aspect. It would seem therefore 

 that the toxin developed within the blood of the larva is more active 

 than that formed in cultures on artificial media. This toxin is sus- 

 ceptible to the action of heat ; prolonged heating at 127°-131°F. 

 (53°-55°C.) destroys it almost entirely. 



Metalnikow^ (S.). B. dysenterique et bacteriophage de d'H6relIe chez 

 les Chenilles de Galleria meUonella. — C. R. Soc. Biol., Paris, Ixxxiii, 

 no. 16, 8th May 1920, pp. 667-668. 



It has previously been shown [R.A.E., A, viii, 163] that the larvae of 

 Galleria tndonella are very susceptible, not only to saprophytes but 

 also to the microbes of intestinal organisms such as Bacillus coli, and 

 the Bacillus of Shiga. The latter always produces a fatal infection, 

 1/80 c.c. of emulsion kilhng a larva in 15 to 25 hours. Phagocytosis 

 is almost entirely absent, and the bacilh reproduce with great rapidity, 

 so that in two to three hours after inoculation the whole body cavity 

 of the insect is full of microbes. 



The author has conducted a series of experiments to test whether 

 injections of d'Herelle'^ bacteria-destroying organism would confer 

 any immunity on the larvae. Five larvae inoculated with 1/50 c.c. 

 of a fairly strong emulsion of de Shiga's dysenteric bacillus were all 

 killed in 24 hours. Five others similarly treated, but receiving ten 

 minutes before an injection of a small dose of d'Herelle's organism, were 

 all hving after 24 hours. This immunity however does not last long. 

 It appears that d'Herelle's organism has no influence on the develop- 

 ment of the disease for the first two or three hours. After that the 

 number of microbes diminishes rapidly. Most of the bacilH swell up 



