19 



Mr. J. T. Cunningham, M.A., F.Z.S., read a paper on the 

 resemblance in form and markings of the plates of paraffin-wax 

 originally obtained by Prof. Kappers, of Amsterdam, to the shells 

 of Molluscs. Examples of these structures had been exhibited 

 at a previous meeting by Mr. R. H. Burne, Y.P.Z.S. Mr. 

 Cunningham found that the forms were produced by pouring 

 molten paraffin-wax on to the surface of cold water, and he had 

 no doubt that Prof. Kappers's specimens were produced in the 

 same way by the molten wax running over on to a vessel filled 

 with water. The surface-layer of the wax was cooled by contact 

 with the water, then the flowing wax was piled up on the cooled 

 film till the surface-tension gave way and the wax flowed over, 

 and being cooled in its turn formed an additional zone of wax 

 beyond the original edge, and so on in succession. Thus the 

 parallel lines of increment seen on the underside of the wax 

 plate were produced, just as the parallel lines on Mollusc shells 

 are produced by periodical increments of growth. The author 

 concluded that the form and markings were not in, either case 

 in any way due to effects of crystallization as Prof. Kappers 

 supposed. By causing the water to rotate spiral forms were 

 produced, and either right- or left-handed spirals could be pro- 

 duced at will according as the water was stirred to the right or 

 left. The author concluded with a demonstration, pouring 

 molten wax on to a dish of water and showing the shell-like 

 appearance of the cooled plate of wax. 



The next Meeting of the Society for Scientific Business will be 

 held on Tuesday, April 13th, 1915, at half-past Five o'clock p.m., 

 when the following communications will be made : — 



G. A. Boulenger, F.R.S., F.Z.S . 



A List of the Snakes of the Belgian and Portuguese Congo, 

 Northern Rhodesia, and Angola. 



R. Broom, M.D., D.Sc, C.M.Z.S. 



1. On some new Carnivorous Therapsids in the Collection of 

 the British Museum. 



2. On the Organ of Jacobson and its Relations in the 

 " Insectivora." 



