QUEKETT MICROSCOPICAL CLUB. 339 



at the close of the paper, and many of those present bore testi- 

 mony to the interesting and valuable character of the communi- 

 cation. Mr. Bryce said that he had spent some time with 

 Mr. Harris, and was much struck with the richness of the neigh- 

 bourhood in all kinds of life. He had found his time quite taken 

 up with the Rotifera (his own special field), of which there was 

 abundance. Mr. J. AVilson, one of those mentioned by Mr. 

 Harris, said those who had not experienced it could hardly 

 realise the tremendous amount of work entailed by such a paper. 

 He had great pleasure in proposing a hearty vote of thanks 

 to the writer. This was seconded and dulv carried. 



At the 524: th Ordinary Meeting of the Club, held on April 24th, 

 1917, the President, Dr. A. B. Rendle, F.R.S., in the chair, the 

 minutes of the meeting held on March 27th were read and con- 

 firmed. 



Messrs. Charles H. Smith, Charles F. Sonntag, and William 

 R. Chappie were balloted for, and duly elected members of the 

 Club. 



Dr. J. Rudd Leeson, F.R.M.S., then gave a lectm'e '' On the 

 House Fly, Musca domestica, with Special Reference to its Danger 

 to Health." This was illustrated by sixty lantern slides, and a 

 selection of preparations which were exhibited under micro- 

 scopes on the table. In his address which accompanied the 

 lantern views Dr. Leeson said : "It was not till 1882 that flies 

 were known to be the bearers of disease — then malaria was 

 traced to the mosquito. Nothing was known about the house 

 fly in relation to disease till 1905. Of all creatures it is the one 

 most commonly associated with man — everjrvvhere, from the 

 Polar regions to the Tropics. It is now known to be the carrier 

 of the microbes of anthrax, infantile diarrhoea, cholera (10,000 

 colonies were obtained from one fly), typhoid (the microbes have 

 been found in its intestines twenty- three days after ingestion), 

 ophthalmia, tuberculosis, diphtheria, pneumonia, etc. A 

 house fly was allowed to walk over a plate of sterilised gelatine 

 and a few hours later 46,000,000 germs of typhoid, diphtheria, 

 tubercle and pneumonia were counted." 



Of 414 flies examined, the average number of pathogenic 

 organisms upon each was a million. The fly has therefore been 



JouRN. Q. M. C. Series II.— No. 81. 26 



