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Miss Dorothea M. A. Bate contributed a paper dealing with 

 a collection of vertebrate remains from the Har Dalam Cavern, 

 Malta. Birds are most numerously represented therein, and 

 include some bones of an Anserine bird showing a reduction in 

 its powers of flight. It is believed to be a hitherto-undescribed 

 species, and is referred to the genus Gygnus. A list is given of 

 all the species of vertebrates recorded from the Pleistocene cave 

 and fissu.re deposits of the island. 



Dr. J. 0. MoTTRABi read a paper entitled " An Experimental 

 Determination of the Factors which cause Patterns to appear 

 conspicuous in Nature." 



A series of experiments was carried out with artificial patterns 

 and backgrounds under controlled conditions of lighting, and a 

 large number of determining factors were discovered, both as 

 regards plain and patterned objects and backgrounds. Finally, 

 the experiments showed that the most conspicuous shape and 

 pattern which an object can have, when viewed against a series 

 of plain and patterned backgrounds, was presented by a circular 

 disc of black, with a central circular area of white. Having 

 arrived at this conclusion, the Indian diurnal Lepidoptei-a were 

 completely examined, in order to discover whether any species 

 presented patterns approaching this ideal conspicuous pattern. 

 It was found that a considerable number presented patterns 

 hardly removed from this ideal, and that a large proportion of 

 these insects are considered to be "protected " species presenting 

 " warniuij coloration," 



The next Meeting of the Society for Scientific Business will be 

 held on Tuesday, May 23rd, 1916, at half-past Five o'clock p.m., 

 when the following communications will be made : — 



E. G. BOULENGER, F.Z.S. 



Exhibition of living specimens of the African Lungfish 

 (^Protopterus annectens) and of their Cocoons. 



Lieut. R. Broom, M.D., C.M.Z.S., R.A.M.C. 



On the Structure of the Skull in Chrysocliloris. 



