Presents. [Nov. 17, 



the motion will be stable unless the wave-length of the disturbance 

 lies between about 9/11 and 6/5 of a centimetre. This result satis- 

 factorily explains the effect of oil in calming stormy water. 



III. " On the Colour of the Leaves of Plants and their Autumnal 

 Changes." By ARTHUR HILL HASSALL, M.D. Lond. Com- 

 municated by the Rt. Hon. Professor HUXLEY, F.R.S. 

 Received June 21, 1892. 



IV. " Observations on the Earthquake Shocks which occurred 

 in the British Isles and France during the month of August, 

 1892." By EDWARD HULL, F.R.S., F.G.S., Professor of 

 Geology in the Royal College of Science. Received 

 October 5, 1892. 



Presents , November 17, 1892. 

 Transactions. 



Adelaide : Royal Society of South Australia. Transactions. 

 Vol. XV. Part 1. 8vo. Adelaide 1892. The Society. 



Amsterdam : Koninklijke Akademie van Wetenschappen. Ver- 

 handelingen. Deel XXIX. 4to. Amsterdam 1892 ; Verhande- 

 lingen (Afd. Letterkunde). Deel XX. 4bo. Amsterdam 1891 ; 

 Verslagen en Mededeelingen (Afd. Natuurkunde) . Deel VIII. 

 8vo. Amsterdam 1891 ; (Afd. Letterkunde) Deel VIII. 8vo. 

 Amsterdam 1892 ; Catalogus van de Boekerij. Eerste Vervolg. 

 8vo. Amsterdam 1891 ; Jaarboek. 1891. 8vo. Amsterdam. 



The Academy. 



Baltimore : Johns Hopkins University. Circular. No. 100. 4to. 

 Baltimore 1892 ; Studies. Nos. 49. 8vo. Baltimore 1892. 



The University. 

 Peabody Institute. Report. 1892. 8vo. Baltimore. 



The Institute. 



Batavia: Koninklijke Natuurkundige Vereeniging. Xatuur- 



kundig Tijdschrift voor Nederlandsch-Indie. Deel LI. 8vo. 



Batavia 1892. The Association. 



Berlin : Gesellschaft fur Erdkunde. Zeitschrift. Bd. XXVII. 



Nos. 23. 8vo. Berlin 1892. The Society. 



K. Akademie der Wissenschaften. Abhandlungen. 1891. 4to. 



Berlin 1892; Sitzungsberichte. Heft 140. 8vo. Berlin 



1892. The Academy. 



