206 



York, Albany, February 11, April 13, and June 2; Lyceum of 

 Natural History, New York, February 25, and June 24 ;.Verein fiir 

 Naturkunde in Nassau, Wiesbaden, March 5 5 Real Academia de 

 Ciencias, Madrid, March 30 ; President of Bowdoin College, April 

 13 ; acknowledging the receipt of the Society's publications. From 

 the Societe Royale des Sciences de Liege, July 12, 1860 ; Academie 

 Royale des Sciences de Stockholm, November 18, 1860; Royal Geo- 

 graphical Society, London, January 18, 1861 ; K. Preussische Akade- 

 mie, February 28, 1861 ; Verein fiir Naturkunde in Nassau, Wies- 

 baden, March 5, 1861 ; K. Akademie der Wissenschaften, Wien, 

 February 26 and April, 16, 1861, and Gustav Griibner, Leipzig, 

 March 28, 1861, presenting various publications. From the Acade- 

 mia delle Scienze dell' Istituto di Bologna, September 4, 1860 ; K. 

 Preussische Akademie der Wissenschaften, Berlin, October 18, 1860 ; 

 Societe de Physique et d'Histoire Naturelle de Geneve, November 1, 

 1860; K. Gesellschaft der Wissenschaften, Gottingen, February 21, 

 1861, acknowledging the receipt of the Society's pubHcations and 

 presenting their own. From the Geological Survey of India, Cal- 

 cutta, November, 1860 ; K. Physikalisch.-oekonomische Gesellschaft, 

 Konigsberg in Pr., November 13, 1860 and May 6, I86I ; Naturfors- 

 chende Gesellschaft zu Bamberg (Bayern), December 15, 1860; 

 Verein zUr Beforderung des Gartcnbaues, Berlin, February 18, 

 1861 ; Dublin University Zoological and Botanical Association ; 

 Botanical Society of Canada, August 9, 1861, presenting their 

 various publications and desiring an exchange. K. Hof-und Staats- 

 Bibliothek, Miinchen, December 20, 1860 ; Royal Society of London, 

 March 18, 1861, acknowledging the receipt of the Society's pubHca- 

 tions, and asking that deficiencies may be supplied, and presenting 

 various publications. K. Bayerisch. Akademie der Wissenschaften, 

 Miinchen, December 20, 1860, acknowledging the receipt of the So- 

 ciety's publications, and asking that missing numbers may be supplied. 



September 18, 1861. 



The President in the Chair. 



Dr. Bacon exhibited five specimens of siliceous calculi 



from the urinary organs of animals ; four from the ox, and 



one from the sheep ; and read the following account of these 



and other cases : — 



Siliceous Ukinary Calculi. By John Bacon, m.d. 

 Genuine siHceous calcuH are so extremely rare that the following 

 list includes all tlie cases which I have been able to find on record o^ 



