DAVENPORT. — EVOLUTION OF PECTEN. 



159 



APPENDICES I, K. 



Correlation Surface : Ears and Antero-posterior Diameter. 



Irish Sea. Length of Ears. 



Anterior, millimetres. 

 M= 17.255 ± .040 ; o- = 1.375 + e .028. 



Posterior, millimetres. 

 Af = 14.821 ± .040 ; o- = 1.378 ± .028. 



o 



-H 



lO 



eg 



o 



-H 



00 



— 

 to 



8 9 10 11 12 13 14 15 16 17 



18 19 20 21 



1 2 4 12 2H S9 155 181 47 21 2 



7 9 10 1112 13 14 15 16 17 18 19 20 



= 541 1 2 5 7 8 42 139 162 138 30 4 3 



2 

 2 



4 

 3 

 1 

 5 



6 



8 



13 



12 



19 



28 



26 



34 



32 



27 



58 



43 



33 



36 



33 



32 



16 



17 



16 



10 



8 



3 



1 



3 



= 541 



