Proceedings. 93 



L. concentricus, also of Reeve, next which it must be placed. 

 This specimen, at present the only one known, formed part 

 of the collection of Sir David Barclay, Bart. I also 

 acquired, at the same opportunity, and from the same 

 collection, the fine type of Latirus {Leucoaonici) BelcJieri 

 (Ad.), and two varieties of L. rudis (Reeve), of a light 

 fawn colour, with darker shading at the channels of 

 the angles, which at first sight, seemed a distinct 

 species. Also two very extraordinary varieties of L. 

 nodatus, which Sir David Barclay valued highly, and 

 considered different from that species, though at present I 

 cannot see my way to separate them. They have the 

 umbilicus widely developed, which is not the case in 

 normal nodatus, but as I have before shown this trait varies, 

 in most of the known species, especially amongst the 

 larger kinds." 



Mr. Faraday described some phenomenal effects of 

 the recent and previous gales on buildings — windows and 

 walls being apparently drawn out in the teeth of the wind 

 instead of being blown in — and suggested that approximate 

 vacua, or great diminutions of external pressure, might result 

 from the swirling or other action of the wind when sweeping 

 round corners, or encountering obstructions, the result being 

 a kind of suction similar to what might be observed in the 

 eddies of streams. A discussion ensued, in which Professor 

 Osborne Reynolds, Mr. Harry Grimshaw, Mr. Francis 

 Nicholson, Mr. Gwyther, and others, took part, various 

 suggestions being made as to possible pressure of wind 

 entering by chimneys or doors on the inside of the windows 

 or walls of buildings. 



Mr. Alex. Hodgkinson, M.B., B.Sc, read a paper, 

 entitled " On Iridescent Colours and a Method of Examining 

 Iridescent Objects — Birds, Insects, and Minerals — so as to 

 ensure Uniformity of Description." 



