556 SUMMARY OP CURRENT RESEARCHES RELATING TO 



Dangers from the Excrement of Flies.* — B. Grassi describes 

 experiments which show that flies are agents in the diffusion of 

 infectious maladies, epidemics, and even parasitic diseases. 



On a plate on the table of his laboratory he placed a large number 

 of the eggs of a human Nematode parasite (TrichocepJialus). After a 

 few hours he found, on some white sheets of paper hanging in the 

 kitchen, the well-known spots produced by the excreta of the flies, and 

 on a microscopical examination of these spots, several of the eggs of the 

 parasite were found in them. Some flies coming into the kitchen were 

 now caught, and their intestinal tract was found quite filled with an 

 enormous mass of faecal matter, in which the presence of eggs of 

 Trichocephali were detected. As it was practically impossible to keep 

 all alimentary substances from contact with these flies, it follows that 

 the chances of Dr. Grassi and his family being infected with Tricho- 

 cephali were very great. As a matter of fact, the experiment was 

 tried with non- segmented eggs of this worm. Another experiment 

 was in the same direction. Dr. Grassi took the ripe segments of 

 a Tcenia solium (which had been in spirits of wine) and broke 

 them up in water, so that a great number of the tapeworm's eggs 

 remained suspended in the fluid. The flies came to the mixture, 

 attracted by the sugar, and in about half an hour the ova of the tape- 

 worms were to be found in their intestines and in the spots. Had 

 these eggs been in a recent and living state, they would doubtless 

 have been just as easily transported. To those who care to try these 

 experiments, it is suggested that lycopod powder mixed with sugar and 

 water is a good material, as the lycopod spores are easily detected. 



It is self-evident that if the mouth-apparatus of the fly will admit 

 of the introduction of such objects as have been above noted, that there 

 will be no difficulty in its admitting scores of the spores of many 

 parasitic fungi, and above all of those belonging to the Schizomycetes, 

 the possible cause of so much disease. Already Dr. Grassi has detected 

 in fly excrement the spores of Oidium lactis, and the spores of a Botrytis, 

 this latter taken from the bodies of silkworms dead of muscardine. 



There arises, of course, the question of how far the active 

 digestion of the intestines of the flies may not destroy the vitality of 

 germs or spores thus taken in, but it would seem probable that in 

 many instances the larger bodies swallowed may not serve as objects 

 for assimilation, but may be got rid of as foreign bodies, and it will 

 be borne in mind that the flies themselves fall victims to the growth 

 of a parasitic fungus (Empusa muscoe Cohn), which is probably taken 

 first into their own stomachs. 



)3. Myriopoda. 

 Nerve - terminations on Antennae of Chilognatha.t — A pre- 

 liminary note upon these structures is contributed by 0. Biitschli ; 

 the results were worked out by Dr. B. Sacepine in conjunction with 

 Dr. Biitschli, but having been left in an incomplete condition, a brief 

 resume of the more important new facts seemed desirable. 



* Arch. Ital. Biol., iv. (1883). See Natiare, xxix. (1884) pp. 482-3. 

 t Biol. Centralbl., iv. (1884) pp. 113-6 (2 figs.). 



