THE AMERICAN LOBSTER. 
51 
determined either (a) on the basis of the number of eggs to the gram, or ( b ) by the weight 
of 1,000 eggs. The numbers obtained by the last two methods agree very closely, and 
it is plain that the dry method is the most reliable. The wet method gives a number 
which is from 3 to 4 per cent greater than that obtained by the dry method. There 
is probably a constant error of this amount in the wet method, 1 and this .slight error is 
due to the presence of the stalk of the secondary egg membrane, which has a tendency 
to keep the wet eggs apart, but which shrivels and cracks off when dry. It increases 
the buoyancy of the fresh eggs and is the cause of the bunching commonly observed. 
The excess due to the bunching of the eggs is about 0:3 per cent. This source of error 
was eliminated in No. 09 of the table, where the eggs were separated with needles 
before measuring. 
THE LAW OF PRODUCTION. 
4 
In table 15 I have reduced the results of a very large number of observations 
made upon lobsters varying from 8 to 19 inches in length. The total number examined 
is 4,045. Of these, 1,678 were taken on the ledges 15 miles southwest of No Man’s Land 
Island from April 20 to June 16, 1894. The remaining 2,967 were captured in Vineyard 
Sound and in the vicinity of the Elizabeth Islands from April to June, 1889-94. A 
smaller number were taken in February during the same years. The eggs went to 
supply the hatchery of the United States Fish Commission. 
Table 15 . — Production of eggs. 
Length of 
lobster. 
Smallest 
number 
of eggs. 
Largest 
number 
of eggs. 
Average 
number 
of eggs. 
Number of 
lobsters 
examined. 
Length of 
lobster. 
Smallest 
number 
of eggs. 
Largest 
number 
of eggs. 
Average 
number 
of eggs. 
Number of 
lobsters 
examined. 
8 inches 
3, 045 
9, 135 
4, 822 
6 
13 inches 
6, 090 
48, 720 
28, 610 
321 
8£ inches - . . . 
6, 090 
7. 612 
6,851 
2 
13J inches 
24, 360 
48, 720 
33, 495 
5 
8£ inches 
3, 045 
12, 180 
6, 935 
9 
13j inches 
6, 090 
54, 810 
32, 858 
146 
8§ inches 
6, 090 
9, 135 
7, 105 
3 
13| inches 
42, 630 
42, 630 
42, 630 
2 
9 inches 
3, 045 
18, 270 
7,902 
143 
14 inches 
6, 090 
85, 260 
36, 960 
426 
6 090 
12, 180 
9, 083 
35 
91 3 1 r» 
fiO 900 
49 908 
9A inches 
3,045 
20, 792 
9, 297 
241 
15 inches 
12 ! 180 
97:440 
46 1 524 
280 
3,045 
15, 225 
9, 947 
55 
54, 810 
1 
10 inches 
3. 045 
24i 360 
10: 555 
514 
15£ inches 
24, 360 
97, 440 
53, 795 
45 
10£ inches 
6, 090 
22, 838 
11,622 
61 
L5§ inches 
48, 720 
54, 810 
50, 750 
3 
101 inches 
3,045 
36, 540 
12, 905 
532 
Hi inches 
24, 360 
97, 440 
57, 146 
103 
6, 090 
24, 360 
14, 067 
66 990 
1 
13 
11 inches 
3 , 045 
48i 720 
15: 410 
568 
16£ inches 
36, 540 
85, 260 
66, 053 
11 £ inches. . . . 
6, 090 
25, 882 
17, 102 
43 
17 inches 
12, 180 
85, 260 
63, 336 
30 
Ill inches 
3,045 
42, 630 
18, 668 
307 
171 inches 
00, 900 
73, 080 
64, 960 
3 
Ilf inches 
12, 180 
24, 360 
17, 993 
11 
18 inches 
60, 900 
91, 350 
77, 430 
7 
12 inches 
3, 045 
54, 810 
21,351 
414 
19 inches 
54. 810 
91, 350 
77, 647 
4 
18, 270 
27, 405 
23, 396 
8 
12| inches 
9,' 135 
42: 630 
24: 812 
156 
Total number examined 
4, 645 
122 inches 
18, 270 
42, 630 
26, 390 
12 
The average number of eggs of a lobster of a given length has little value unless 
obtained from a large number of individuals. While the small number of eggs 
occasionally recorded for lobsters over 12 inches long may be the result of loss, in 
lobsters under this size it is probably more often due to belated sexual maturity. 
1 This excess will probably about offset the slight loss of eggs which must always occur. The 
numbers given in table 15 do not therefore require correction on this account. 
