APPARENTLY CORRELATED TO THE CONDITIONS OF LIFE. 
:P2l 
(6.) Shells Varying in Length between 26 mm. and 20 mm. 
Measurements of shells in millimetres. 
Average breadth of shells having the same length. 
Ratio of length to 
breadth. 
Length. 
Breadth. 
Length. 
Average 
breadth. 
Number of 
shells. 
26 
20 
26 
20 
1 
1 : 0-76 
25 
19(2), 18-5 
25 
18-8 
3 
•75 
24-5 
19 
24-5 
19 
1 
! -77 
24 
19, 18(2) 
24 
18-3 
3 
1 -'7 
23 
17(2) 
23 
17 
2 
‘ -73 
22 
18(^), 17-5(2), 17(2) 
22 
17-5 
8 
1 -79 
21 
17, 16 
21 
16-5 
2 
•78 
20-5 
16 
20-5 
16 
1 
•78 
20 
16, 15-5, 15(2) 
20 
15-3 
4 
•76 
10-5 
15-5, 15 
19-5 
15-2 
2 
•75 
19 
15-5(3), 15 
19 
15-3 
3 
•80 
Average ratio of lengtli to breadth in 30 shells varying in length between 26 mm. and 20 mm. 
is 1 : 0'770. 
The Third Terrace, 
1 Measurements of shells in millimetres. 
i 
Average breadth of shells having 
the same length. 
Ratio of length to 
breadih. 
1 Length. 
Breadth. 
Length. 
Average 
breadth. 
Number of 
shells. 
1 22 
17, 16 (i) 
22 
16-2 
5 
1 : 0-73 
j 21-5 
16-5, 16(i), 15 
21-5 
15-9 
6 
•74 
; 21 
16-5, 16(3), -L5 
21 
15-9 
5 
•75 
20 
16(2), 15(3) 
20 
15-4 
5 
•77 
1 19-5 
15 
19-5 
15 
1 
•76 
i 19 
15 ( 2 ), 14-5^ 14(2) 
19 
14-5 
5 
•76 
i 18 
1 
1 
14-5, 14, 13 
18 
13-8 
3 
•76 
Average ratio of length to breadth in 30 shells varying in length between 22 mm. and IG mm. 
is 1: 0'751. 
•) 
MHCCCLXXXIX.—B. 
T 
