E. H. J. Schuster 



193 



TABLE II. 



Measitreinent No. 1. $. 



This measurement is greater in the shallow water forms by an amount about 

 twice as great as its j)n)bable error. 



TABLE III. 



Itiffht Chela Lemjth. ^. 



This measurement is greater in the shallow water forms by an amount between 

 three and four times as great as its probable error, and therefore is probably 

 significant. 



TABLE IV. 



Rigid Chela Length. ?. 



This measurement is greater in the deep water forms by an amount twice as 

 great as its probable error. 



To sum up with regard to the ab.solute measurements of the right chela; in 

 the male they are both significantly greater in the shallow water than in the deep 

 water forms ; while in the female Measurement No. 1 is greater in the shallow 

 water forms, Measurement No. 2 in the deep water forms, and in neither case is 

 the difference, thougli well marked, sufficiently great to be calied significant. 



Biometrika ii 25 



