2 



Prof. W. F. R. Weldon. Certain 



fMar. 3, 



Matthey, Edward, F.C.S. 



Miall, Professor Louis C. 



Newton, Edwin Tully, F.G.S. 



Notter, James Lane, Surgeon- 

 Lieut. -Col. 



Oliver, John Ryder, Major- General 

 R.A. 



Peach, Benjamin Neve, F.G.S. 

 Pedler, Professor Alexander, 

 F.C.S. 



Reade, Thomas Mellard, F.G.S. 

 Roberts, Ralph A., M.A. 

 Rutley, Frank, F.G-.S. 

 Sankey, M. H. P. R., Capt. R.E. 

 Saunders, Howard, F.Z.S. 

 Seebohm, Henry, F.L.S. 

 Sherrington, Charles Scott, M.B. 



Smith, Rev. Frederick John, M.A. 

 Stebbing, Rev. Thomas Roscoe 



Rede, M.A. 

 Stevenson, Thomas, M.D. 

 Stirling, Edward C, M.D. 

 Tuke, Daniel Hack, M.D. 

 Ulrich, Professor George Henry 



Frederic, F.G.S. 

 Veley, Victor Hubert, M.A. 

 Waller, Augustus D., M.D. 

 Waterhouse, James, Colonel. 

 Woodward, Horace Bolingbroke, 



F.G.S. 



Worthington, Professor Arthur 



Mason, M.A. 

 Young, Professor Sydney, D.Sc. 



The Right Hon. Spencer Compton Cavendish, Duke of Devonshire, 

 a Member of Her Majesty's Most Honourable Privy Council, whose 

 certificate had been suspended as required by the Statutes, was 

 balloted for and elected a Fellow of the Society. 



The following Papers were read 



I. " Certain Correlated Variations in Crangon vulgaris." By W. 

 F. R. Weldon, M.A., F.R.S., Fellow of St. John's College, 

 Cambridge, Professor of Zoology in University College, 

 London. Received February 11, 1892. 



The first successful attempt to find a constant relation between the 

 variations in size exhibited by one organ of an animal body and those 

 occurring in other organs was made some three years ago by Mr. 

 Galton ; and in a paper read before the Royal Society (' Roy. Soc. 

 Proc.,' vol. 45, p. 135) he determined this relation between several 

 organs of the human body. In what follows an attempt is made to 

 apply Mr. Galton's method to the measurement of the correlation 

 between four organs of the common shrimp. Before the details of 

 the measurement are discussed, a short summary of the method will 

 be given. 



Galton's starting point was the fact that each organ of a given race 

 of men varies about its mean size to an extent and with a frequency 



indicated by the probability equation (y = ^ e~ x ° z \ If two 

 variable organs are known to vary in this way, and if they are so 



