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frequently and easily demonstrated. The thread could be 

 isolated by dissolving away the silica with hydrofluoric acid. 

 In the case of calcareous sponges, we should expect to find 

 similar structure j but there had been great uncertainty as to 

 the existence of such a filament. Indeed, it had been definitely 

 stated by eminent authorities that it did not exist. However, 

 he had recently been able to demonstrate the existence of this 

 filament, and a preparation was exhibited under a microscope 

 then on the table. The spicule had been decalcified and then 

 stained with nigrosine, induline, or picric or nitric acid and 

 nigrosine. As would be seen on inspection, the stain had not 

 only affected the known sheath, but also the central organic 

 filament. 



The thanks of the meeting were returned to the various 

 exhibitors, and also to Messrs. Baker for their kindness in 

 providing the microscopes used. 



Mr. F. Martin-Duncan, F.KP.S., gave a lecture, very fully 

 illustrated with lantern photographs, dealing with interesting- 

 points in Insect Life. He said that the study of insect life 

 was a branch of natural science which was growing very greatly 

 in importance. Referring to the photographs he was about to 

 show to the meeting, he said that he had tried all the three- 

 colour processes as they came out, and, while one could get very 

 good renderings of pure colours, one could not get at all satis- 

 factory results in dealing with subtle half-tones and gradation 

 of colours. But in the process brought out by Messrs. Lumiere, 

 of which he was about to show a few specimens, one did get 

 these delicate grades of colour well reproduced, at any rate, to 

 a very large degree. One very great drawback to the em- 

 ployment of the Autochrome plates was their extreme slow- 

 ness. Even in the field, the minimum exposures he had been 

 able to give were two or three seconds, and an insect, for 

 instance, can move considerably in that time. An interesting 

 set of photographs illustrating the fertilising of the early orchid 

 by the bee was shown, and fully described. Mr. Martin- 

 Duncan also told the meeting how a spider which has a 

 coloration very like a flower-bud takes up a position on the 

 upper part of the flower-stalk, and, on a bee alighting on one 

 of the opened flowers just below, springs down and secures its 

 victim, retiring among the lower flowers to enjoy its meal. 



