Contents. vii 



May 12, 1890. page 



On the action of Nicotin upon the Fresh-water Crayfish. By J. N. 



Langley 75 



On a new species of Phymosoma. Arthur E. Shipley .... 77 

 On the action of the Papillary Muscles of the Heart. By J. George 



Adami 78 



On some living specimens of a Land-Planarian found in Cambridge. 



By S. F. Harmer 83 



May 26, 1890. 



On Solution and Crystallization. III. Rhombohedral and Hexagonal 



Crystals. By Professor Liveing 84 



On the Curvature of Prismatic Images, and on Amici's Prism Telescope. 



By J. Larmor 85 



On some theorems connected with Bicircular Quartics. By R. Lachlan 87 



October 27, 1890. 

 On some Compound Vibrating Systems. By C. Chree .... 94 



November 10, 1890. 



Note on the principle upon which Fahrenheit constructed his Therrno- 



metrical Scale. By Professor Arthur Gamgee . . . . .95 

 On Variations in the Floral Symmetry of certain Flowers having 



Irregular Corollas. By William Bateson and Miss Anna Bateson . 96 

 On the nature of the relation between the size of certain animals and 



the size and number of their sense-organs. By H. H. Brindley . 96 

 On the Oviposition of Agelena labyrinthica. By C. Warburton . . 97 

 Supplementary list of spiders taken in the neighbourhood of Cambridge. 



By C. Warburton 98 



November 24, 1890. 



On the beats in the vibrations of a revolving cylinder or bell. By 



G. H. Bryan 101 



On Liquid Jets. By H. J. Sharpe Ill 



Note on the Application of Quaternions to the Discussion of Laplace's 



Equation. By J. Brill 120 



On a simple model to illustrate certain facts in Astronomy, with a view 



to Navigation. By A. Sheridan Lea 125 



Note on a paper relating to the Theory of Functions. By W. Burnside 126 



