423 



pocket-lens did not fully appreciate its powers, and the man who 

 worked with the compound instrument often rather despised the 

 simple one. A series of photographs of extremely common 

 Diptera were shown, very similar in general appearance to the 

 unaided eye, but easily differentiated with a magnification of 

 three or four diameters. Studies of the head of a living blow- 

 fly as seen .through a Coddington lens were next exhibited. 

 Mr. Smith said that, although the actual examination of objects 

 under such a lens was so simple a process, the satisfactory 

 reproduction of the same effects with the camera was one of 

 the most diflicult branches of nature-photography he had come 

 in contact with. By the man at the farm, flies were generally 

 regarded as harmless nuisances — but altogether by reason of his 

 ignorance, for they are amongst his bitterest enemies. Usually, 

 however, their depredations are apparent when they are in the 

 larval stage, and the farmer does not recognise his foes in the 

 winged form. The Hessian-fly was mentioned, and also the 

 Crane-fly, the parent of the dreaded " leather-jackets." Con- 

 tinuing, the lecturer said that the medical man was now 

 beginning to regard the flies as a curse to humanity. The 

 mosquitoes undoubtedly were responsible for the transmission 

 of malaria and yellow fever ; and sleeping-sickness and the 

 dreaded nagana were carried by species of Gloss ina (tsetse- flies). 

 Even " blow-flies " and house-flies were now in bad odour, it 

 being believed that they were responsible for the dissemination of 

 "summer cholera." The "man in the street" regards the fly 

 simply as a nuisance, especially when it crawls over his bald 

 head. He reads awful accusations against it in the papers, but 

 declines to believe them. Feeling rather badly disposed towards 

 flies in general, the lecturer said that he rather enjoyed the 

 Anal view of the matter — a consideration of those creatures 

 which assisted in the destruction of superabundant flies. Wasps, 

 spiders of many kinds, geckoes, lizards, and tree-frogs were all 

 described and illustrated, and also the microscopic fungus which 

 plays such havoc with flies in the autumn. 



Before adjourning the meeting, the President said he had to 

 thank Messrs. Baker for the loan of the microscopes used in 



