!30 



JOURNAL OF CONCHOI.OGY, VOL. l6, NO. 7, SEPTEMBER, I92I. 



THICKNESS ; mm. 



No. of Individuals. 



m, 



Z' 



o 



H, 

 X 



\ 







\ I 



• 



-Tl 



\ 







\ 1 



» 





\ 







\ 



* 



crq 



\ 







N I 



• 





\ 



\ 









^ 



-1^ 





\ 





c c 



CD 







\ 





< < 



P 







\ 





CD CD 



3 







\ 





H H 



H 







\ 





II II 











V 



CD^ 









\ 





Y* 



01 oi) 



13 





V 



N 



v'Ci 



ro 4i. 



CD 





/ 



\ 



▼L 



+ X 



W 





1 



\ 



R: 



. 2 r 



W 





c 



r 



\^ 



V 1" 







■D 







\ 



k I 







-a 



? 





^^*> 







CD 



CD 





\ • 







-3 







\A^^ 







H 



r 





^^^ 







0' 



3 





\ 



■> 



V^ 







No. of Individuals. 



WIDTH ; mm. 



WIDTH ; mm 



r r 



9 3 



cp 



X) 





CJI 



0' 







U) 



r 





IT 



m 





XI 



z 









t- 







