194 



Variation in " EnpaginniA Prideauxi" 



TABLE V. 

 Chela Index. ^. 



The chela index is greater in the deep water forms by an amount more than 

 13 times as big as its probable error, antl tberefore certainly significant. 



TABLE VI. 

 Chela Index. J. 



The chela index is greater in the deep water forms by an amount more than 

 six times as big as its probable error, and therefore almost certainly significant. 



Thiis Tables V. and VI. show that in the forms taken from deep water, both 

 male and fcmale, a greater proportion of the wholo length of the chela is taken iip 

 by the blade of the scissors thau in forms taken from shallow water. 



TABLE VII. 

 Carapace Length. ^. 



The mean carapace length in the deep water forms is greater than that of the 

 shallow water forms by an amount mnrp than twicc as great as its probable error. 



