( ^^41 ) 



XIX. — Further Exjperiments on Feeding Insects with the Curved 

 or " Comma " Bacillus. 



By E. L. Maddox, M.D., Hon. F.R.M.S. 



iReud lidi October, 1885.) 



The following details are but an extension of the former paper on 

 the same subject which I had the honour of bringing before the 

 Fellows on the 13th of May last.* It is more incomplete than 

 I deshe, but I think it will be found to extend the views previously 

 announced, that the comma bacillus from cultures can pass in a 

 living state through the digestive tracts of the insects experimented 

 upon, and that under these conditions the insects become possible 

 carriers of contagion, and may infect food by their dejections. Of 

 course I am only supposing, not affirming, that Koch's views in 

 reference to this particular microbe, and the part it plays in cholera, 

 are correct. 



Dr. Grassi, of Eovellasca, in the summer of 1883 published f the 

 results of some interesting observations he had made, and contended 

 that insects, especially flies, may be considered as veritable authors 

 of epidemics and agents in infectious maladies. He put on a plate 

 in his laboiatory some ova of the Trichocejjhahis, and found they 

 had been deposited with the excreta on bits of white paper placed 

 in the kitchen, some little distance away. He captured some of 

 the flies, and discovered the digestive tube full of masses of feculent 

 matter abounding with the ova. Then he remarks on the danger the 

 entire family were exposed to, if the ova could be afterwards 

 developed. He also put segments of tape-worm, Tsenia solium, 

 that had been for some time preserved in alcohol, into water, some 

 of the ova remained suspended, the flies drank of the fluid, and in 

 less than one hour he found the ova in their intestines and also 

 emitted in then* dejections, and says, had they been living the family 

 might have been infected. Flies, he states, can also transmit the 

 ova of the small thread- worm, Oxyuris. He moistened sugar with 

 Lyco2)odium, and allowed flies to feed on this, and also ofi" the blood 

 of frogs and toads, and then found the spores and the blood-cor- 

 puscles in their intestines. Ho therefore thinks, as the buccal 

 passages permit of the transit of these large bodies, they could the 

 more easily transmit the ^chizomycetes. He let flies feed off some 

 mildewed cream, and then found the Oidium lactis within them, 

 and flies feeding ofi" silk-worms dead of muscardine, after a short 

 time, passed in their dejections the spores of the Botrytis, the cause 



* See thiB Journal, ante, p. G02. 



t Arch. Ital. Biol., iv. (1883) pp. 205-8. Bull. Soc. Entomol. Ital., xv. (1883) 

 pp. 348-9. See this Journal, iv. ''1881) p. 550'. 



