324 
W. BATESOX ON- SOME VARIATIONS OF CARDIUM EDTJLE 
The Seventh Terrace. 
Shells Varying in Leng-th between 21 mm. and 16 mm. 
Measurements of shells in millimetres. 
Average breadth of shells having the same length. 
Ratio of length to 
breadth. 
Length. 
Breadth. 
Length. 
Average 
br adth. 
Mumber of 
shells. 
21 
15 
21 
15 
1 
1:0-71 
20-5 
15 
20-5 
15 
1 
-73 
20 
15(3), 14.5, 14(3) 
20 
14-5 
1 
•72 
19-5 
13-5 
19-5 
13-5 
1 
•69 
19 
14-5, 14(2), 13 
19 
13-8 
4 
•72 
18-5 
13 
18-5 
13 
1 
•70 
18 
14(2), 13-5(3), 12 
18 
13-4 
5 
•74 
17-5 
13, 12 
17-5 
12-5 
2 
•71 
17 
13(2), 12(^) 
17 
12-3 
6 
•72 
16 
13, 12 
16 
12-5 
2 
•78 
Average ratio of lengtt to breadth in 30 shells varying in length between 21 mm. and 16 mm. 
is 1:0-725. 
Table III. — Jaksi Klich. 
Shells of the Outer Dei'yosits Varying in Length between 22 mm. and 17 mm. 
Measurements of shells in millimetres. 
Average breadth of shells having 
the same length. 
Ratio of length | 
to breadth. 
1 
Length. 
Breadth. 
Length. 
Average 
breadto. 
Xurnber of 
shells. 
22 
16(3) 
22 
16 
0 
0 
1:0-72 i 
21 
16(3), 15.5^ 15(3^ 
21 
15-7 
7 
•74 
20 
15(7), 14-.5, 14 
20 
14-8 
9 
•74 
19-5 
14(2) 
19-5 
14 
2 
•71 
19 
15, 14 
19 
14-5 
2 
•76 
18-5 
14(2) 
18-5 
14 
2 
•75 
18 
14, 13(2) 
18 
13-3 
3 
•73 
17-5 
13-5 
17-5 
13-5 
1 
•77 
17 
14 
17 
14 
1 
•82 
Average ratio of length to breadth in 30 shells varying in length between 22 mm. and 17 mm. 
is 1 : 0-740. 
