328 
MR, W. BATESON ON SOME VARIATIONS OF CARDIUM EDULE 
Table VII. — Shells from the Shore of Abu Kir. 
Measurements of shells in millimetres. 
Average breadth of shells having the same length. 
Eatio of length to 
breadth. 
Length. 
Breadth. 
Length. 
Average 
breadth. 
N umber of 
shells. 
24 
17-5, 17 
24 
17-2 
2 
1 : 0-71 
23 
17, 16, 15-5 
23 
16 
3 
•69 
22-5 
17-5, 16-5, 15-5 
22-5 
16-5 
3 
•73 
22 
16, 1.5-5, 15 
22 
15-3 
3 
•69 
21-5 
15(5), 14 
21-5 
14-8 
6 
•68 
21 
16, 15-5, 15(2) 
21 
15-3 
4 
•72 
20-5 
15 
20-5 
15 
1 
•74 
20 
14-5, 14(5) 
20 
14 
6 
•70 
19-5 
14-5, 14 
19 
14-2 
2 
•75 
Average ratio of length to breadth in 30 shells varying in length between 24 mm. and I9'5 mm. 
is 1 : 0738. 
Table VIII. 
This Table gives the results of the previous Tables. The extremes of length of the 
shells measured for these averages are given in millimetres, and the average breadths 
are given in terms of the length, which is taken as 1. 
Locality. 
Level. 
Smaller samples. 
Larger samples. 
Extremes 
of length. 
Average 
breadth. 
Extremes 
of length. 
Average 
breadth. 
Shore of Ai-al Sea. 
22 -18-5 
0-761 
Shumisb Knl. 
First terrace . 
21 -17 
0-799 
Second terrace . 
21 -17 
0-782 
26-19 
o 
o 
Third terrace. 
22 -18 
0-751 
i 
Fourth terrace . 
21 -16 
0-735 
26-18 
0-730 
1 
Fifth terrace . 
21 -16 
0-743 
27-21 
0-731 
Seventh terrace . 
21 -16 
0-725 
Jaksi Klich. 
Upper deposit . 
22 -17 
0-740 
Lower deposit . 
25-5-19 
0-682 
30-25-5 
0-660 
Jaman Rlich. 
Lower dejiosit . 
•24 -16 
0-726 
Shore oE Mareoti.s. 
, . 
27-20 
0-6S0 
Ramleh Lake No. 2 (fresh-water). 
21 -17 
0-665 
29-16-5 
0-657 
Shore of Abu Kir. 
24 -19-5 
0-738 
1 
