6 PEOCEEDlNCtS OE IHJil 



head Moth (Acherontia Atropos), and proved with a stethoscope that 

 the late Prof. Moseley was correct in stating that the sound comes 

 from the proboscis. He also showed that all sound ceased the 

 moment the tip of the straightened proboscis was dipped in water, 

 and could not be resumed until the organ was withdrawn; thus 

 supporting Prof. Moseley's opinion that the sound was produced by 

 forcing air through the proboscis. 



Prof. Po niton also exhibited projected photographs of Acrcea 

 unicolor var. alcippina, recently received from Sierra Leone by 

 Mr. Herbert Druce, F.L.S., together with specimens of Limnas 

 cJirysippus var. alcippus, which they closely resemble. He showed 

 that this Acra^a is represented in the South and East Central 

 regions of Africa by varieties which correspond to the respective 

 forms of L. chrysippus : that in fact the geographical coincidence 

 between the two is much closer than with the forms of the female 

 of Hypolimnas misippus and those of L. chrysippus. The former 

 is one example of Miillerian mimicry, both forms being inde- 

 pendently distasteful ; while the female Hypolimnas is generally 

 regarded as a Batesian mimic. 



In a discussion which ensued, Col. Swinhoe, Mr. Herbert Goss, 

 and Prof. Farmer took part. 



The following papers were read : — 



1. " On the Structure and Habits of the Ammocharidce" By 

 Arnold T. Watson, F.L.S. 



2. " On the Flora of Vavau, one of the Tonga Islands." By 

 I. H. BurkiU, F.L.S,, and C. S. Crosby, M.A. 



January 17th, 1901. 

 Prof. S. H. Vines, M.A., F.E.S., President, in the Chair. 

 The Minutes of the last Meeting were read and confirmed. 

 Mr. James Alfred Wheldon was elected a Fellow of the Society. 



The President announced that the " Bressa Prize," offered by the 

 '• Academic Eoyale des Sciences de Turin," would be awarded for 

 the most striking and useful discovery in physical and experimental 

 science, natural history, pure and applied mathematics, physiology, 

 not excluding geology, history, geography, and obstetrics. The 

 value of the prize offered is 9600 francs, or nearly .£400, and the 

 competition is open to experts and inventors of all nations, the com- 

 petition closing on the 31st Dec. 1902. 



The President also announced that the Imperial and Eoyal 

 Zoological and Botanical Society of Vienna would celebrate its 

 Jubilee Anniversary on the 30th March, 1901, to which represen- 

 tatives of other Scientific Societies were cordially invited. A 

 notification from those intending to be present is requested not 

 later than the middle of February. 



