1892.] Correlated Variations in Crangon vulgaris. 15 



Table IX.^Mean Length of Post-spinous Portion for every observed 

 Value of Total Carapace Length. (Helder : 300 individuals.) 



M c = 251-38 ; Q, c = 4-36. M ps = 181-67 ; = 4*02. 



Length of e. 



Mean associated 

 length of ps. 



Lengtli of ps when 

 r = 0-83. 



Difference 

 observed, ps. 



Over 256 



187-98 



188 -28 



-0-30 



256 



183 '85 



185 -21 



-1-36 



255 



184 -09 



184 -44 



-0-36 



254 



185 '08 



183 -67 



+ 1-41 



253 



182 -56 



182 -90 



-0-34 



252 



181 -48 



182-13 



-0-65 



251 



179 -83 



181 -64 



-1-81 



250 



179 -87 



180-60 



-0-73 



249 



179 -42 



179 -83 



-0-41 



248 



178-37 



178 -93 



-0-56 



Under 248 



176 -11 



176-19 



+ 0-08 



Table X. — Mean Value of Total Carapace Length for every observed 

 Length of Post-spinons Portion. (Helder : 300 individuals.) 



Length of ps. 



Mean associated 

 length of c. 



Length of c when 

 r = 0-S3. 



Difference 

 observed, c. 



Over 187 



259 -97 



260-57 



-0-60 



187 



254-83 



256-19 



-1-36 



186 



255-92 



255 -18 



+ 0-74 



185 



255 -05 



254 -38 



+ 0-67 



184 



252-56 



253 -48 



-0-92 



183 



253 -28 



252 -57 



+ 0-71 



182 



251-78 



251 -66 



+ 0-12 



181 



250-63 



250-77 



-0-14 



180 



249 -92 



249 -86 



+ 0-06 



179 



247 -31 



248-99 



-1-68 



178 



248 -95 



248 -09 



+ 0-86 



Under 178 



247-00 



1 



243 -89 



+ 3-11 



