THE AMERICAN LOBSTER. 
45 
a series of similar drawings of embryos developing under normal conditions from 
summer eggs. 
The eye pigment furnishes the most convenient scale for the measurement of the 
rate of development of the embryo as a whole, since it appears early, is clearly defined, 
and since the development, of the eye is correlated with that of the other organs of the 
body. Where the ocular pigment forms a thin crescent in eggs taken in January, 
the embryo will be found in a stage of development similar to that reached in the 
summer eggs four weeks after fertilization. In such a case, it is a safe inference that 
the ova have been laid in the fall. Again, when in May or early June the area of 
ocular pigment is not greater or is less than that observed in summer eggs by the first 
of September (cut 36, pi. J), we may be confident that such eggs were extruded later 
than the previous summer. 
Table 11 . — Number of egg-lobsters taken at Woods Hole. ( See table 21.) 
Time. 
F emales 
with eggs. 
(&) 
Females 
with eggs 
laid in 
J uly and 
August. 
Females 
with eggs 
laid out of 
season. 
(a) 
Percentage 
of a to b. 
1893. 
December 
22 
17 
5 
22.1 
1894. 
January 
36 
24 
12 
334 
February 
11 
9 
2 
18 
March 
12 
9 
3 
25 
April 
33 
26 
7 
21 
May 
34 
26 
8 
23.5 
June 
20 
13 
7 
35 
Total 
168 
124 
44 
25.5 
Table 12 shows the stage of development of the eggs of 44 lobsters taken under 
the conditions described (p. 25) and compared ivith the normal condition of summer 
eggs shown in table 18, lobster No. 3 (1) to (20). These comparisons are rendered 
clearer by a series of drawings (cuts 23-38) made from the eggs of this lobster. 
Table 12. — Stage of development of eggs laid in fall and winter at Woods Hole. 
No. 
Date. 
Length 
in 
inches. 
Stage of development. 
No. 
Date. 
Length 
in 
inches. 
Stage of development. 
1893. 
1894. 
. 
1 
Dec. 
20 
101 
No eye pigment. Like stage 3 
22 
Mar. 
15 
94 
Like 3 (11), table 18. 
(7), table 18. 
23 
Apr. 
16 
10 
Little earlier than 3 (10), table 18. 
2 
Dec. 
23 
9* 
Forked telson overlaps brain. 
24 
Apr. 
17 
10 
Like 3 (9), table 18. 
Like preceding. 
25 
Apr. 
17 
10 
Little earlier than 3 (10), table 18. 
3 
Dec. 
25 
8 
Like 3 (11), table 18. 
26 
Apr. 
18 
11 
Little earlier than 3 (9), table 18. 
4 
Dec. 
26 
10i 
Like 3 (7), table 18. 
27 
Apr. 
19 
84 
Like 3 (9i, table 18. 
5 
Dec. 
27 
8 
Trifle later than 3 (9), table 18. 
28 
Apr. 
20 
10| 
Like 3 (10), table 18, 
1894. 
29 
Apr. 
21 
9 
Little earlier than 3 (9), table 18. 
6 
Jan. 
1 
Like 3 (9), table 18. 
30 
May 
l 
104 
Little earlier than 3 (10), table 18. 
7 
Jan. 
2 
Like 3 (10), table 18. 
31 
May 
1 
7 X 
Like 3 (10), table 18. 
8 
Jan. 
3 
m 
Like 3 (9), table 18. 
32 
May 
3 
101 
Little earlier than 3 (9), table 18. 
9 
Jan. 
3 
94 
Like 3 (11), table J8. 
33 
May 
8 
94 
Like 3 (9), table 18. 
10 
Jan. 
4 
9 
Eye pigment just visible. 
34 
May 
9 
10 
Like 3 (9), table 18. 
n 
Jan. 
9 
10 
Like 3 (6), table 18. 
35 
May 
10 
10 
Little later than 3 (9), table 18. 
12 
Jan. 
11 
10i 
Like 3 (10), table 18. 
36 
May 
11 
7 
Little later than 3 (9), table 18. 
13 
Jan. 
12 
10 
Like 3 (10), table 18. 
37 
May 
12 
9 
Little earlier than 3 (9), table 18. 
14 
Jan. 
13 
10 
Like 3 (9), table 18. 
38 
J une 
7 
9 
Like 3 (11), table 18. 
15 
■Jan. 
20 
9 
Like 3 (10), table 18. 
39 
June 
7 
11 
Like 3 (11), table 18. 
16 
Jan. 
27 
10 
Like 3 (10), table 18. 
40 
June 
9 
84 
Like 3 (11), table 18. 
17 
Jan. 
31 
10 
Like 3 (9), table 18. 
41 
J une 
8 
11 
Little earlier than (11), table 18. 
18 
Feb. 
19 
9i 
Like 3 (11), table 18. 
42 
J une 
ii 
10* 
Like 3 (11), table 18. 
19 
Feb. 
5 
9 
Like 3 (9), table 18. 
43 
June 
12 
10 
Like 3 (11), table 18. 
20 
Mar. 
10 
104 
Like 3 (11), table 18. 
44 
J une 
14 
9* 
Like 3 (11), table 18. 
21 
Mar. 
13 
104 
Like 3 (11), table 18. 
