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Experiments relating to the Compound Eyes of Insects." The 

 paper, which would be illustrated by lantern slides prepared from 

 tli, President's photographs, dealt with the familiar subject of 

 the •• Multiple Image," and would, he thought, prove highly 

 interesting, inasmuch as Dr. Spitta's observations had led him to 

 reject I he accept* d theory of the formation of the multiple image, 

 and to attempt to substitute a new theory of his own to account 

 for the phenomena observed. 



Mr. James Burton then read a paper " On an Easy Method of 

 Si .lining and Mounting Micro-Algae and Fungi," illustrated by 

 i number of specimens displayed under microscopes. Mr. Burton 

 said that in exhibiting micro-objects to friends who were not 

 particularly well acquainted with natural history, it was always 

 not iceable that they showed most interest in "common objects." 

 A fly's foot or scales from a butterfly's wing drew more attention 

 and gave more pleasure than rarer objects which were not 

 understood. Among the objects suitable for popular exhibition, 

 nothing could be more beautiful, when properly displayed, than 

 the very common " moulds," which were universally familiar, 

 and, indeed, only too often more familiar than welcome. But 

 there was considerable difficult} 7 in mounting them, or even in 

 preparing them for exhibition as temporary mounts for trans- 

 mitted light. This was due partly to the fact that the spores 

 were very readily shed, and the whole plant disorganised, in 

 the dry air of a room, and partly to the difficulty of getting 

 water to effectually penetrate it. Some years ago a friend had 

 sent him a bottle of fluid and some specimens of micro-algae 

 preserved in dilute spirit, with the directions, "Wash out the 

 spirit and mount in the fluid." The result was very satisfactory, 

 staining and permanent preservation being effected at the same 

 time, with only one medium. The method was found to answer 

 equally well with fungi, the only difficulty lying in the pre- 

 liminary process. The fluid consisted of glycerine, to which an 

 alcoholic solution of Hoffman's blue was added in sufficient 

 quantity to obtain the desired tint. It was essential that the 

 blue should be of the best quality if permanent results were 

 wanted. Methylen-blue could be used as a substitute, but the 

 colour faded quickly. The method of mounting is as follows: 

 \ drop of alcohol of strength 80 per cent, to 90 per cent, is 

 placed upon a glass slip. A small portion of the fungus is 



