Zimmerm ann: Maturity and fecundity of Atheresthes stomias 
601 
maturity was estimated by substituting 0.5 for P x . 
The constants a and b were estimated through it- 
erative, nonlinear regression by the StatGraphics 
Plus (version 6.1 for DOS) program. 
Total fecundity 
Weighed samples (±0.0001 g) of whole oocytes from 
the most mature females (stage 8, Table 1) were 
counted and measured under a dissecting scope with 
Optimas image analysis software, and numbers were 
expanded to the whole ovary by using the gravimet- 
ric method. Only yolked oocytes, which were opaque, 
appeared as dark images on the computer monitor 
with back lighting. Immature oocytes, which were 
without yolk, were translucent and not discernible 
on the screen. The Optimas software automatically 
measured the area of the oocytes by delimiting the 
circumference, from which the diameters were de- 
rived. Individual measurements of oocyte diameters 
were normalized with a cubic transform (diameter 3 ) 
because the distributions were skewed to the left 
(negatively) (Zar, 1984). Possible differences of oo- 
cyte density (oocytes/gram) and mean oocyte diam- 
eters between ovary lobes were tested with paired t- 
tests. Two-way ANOVA’s were used in testing for dif- 
ferences in oocyte density and diameter among an- 
terior, medial, and posterior positions within the 
same ovarian lobe. 
Possible differences between the weights of the 
eyed-side and blind-side ovarian lobes were tested 
with a paired 7-test, and the relation between the 
lobe weights was described with a linear regression. 
Results 
Maturity 
Gonadal tissue samples were collected from a total 
of 176 female and 58 male arrowtooth flounder. Dam- 
age to the ovarian lobes, or other tissues, and loss of 
ovarian tissue during dissection and storage were 
common in the larger, more mature females. This 
damage or loss of tissue resulted in a lower sample 
size (n=158) for measurements such as GSI and HSI. 
In addition, the ovarian lobes of three fish were so 
small that the lobes were not separated during dis- 
Table 2 
Histological analysis of macroscopic maturity stages. 
Macroscopic 
maturity 
stage 
Microscopic 
maturity 
stage 
Count 
Percent 
Number 
with 
atresia 
Percent 
per stage 
with 
atresia 
Stage A (Immature) 
3 
11 
14.5 
0 
0.0 
4 
51 
67.1 
0 
0.0 
5 
6 
7.9 
5 
83.3 
11 
8 
10.5 
8 
100.0 
Subtotal 
76 
13 
17.1 
Stage B (Developing) 
5 
1 
2.0 
1 
100.0 
6 
3 
6.0 
1 
33.3 
7 
31 
62.0 
6 
19.4 
8 
15 
30.0 
0 
0.0 
Subtotal 
50 
8 
16.0 
Stage E (Spent or resting) 
4 
2 
4.4 
0 
0.0 
5 
13 
28.9 
6 
46.2 
6 
11 
24.4 
2 
18.2 
7 
11 
24.4 
1 
9.1 
8 
4 
8.9 
0 
0.0 
11 
4 
8.9 
4 
100.0 
Subtotal 
45 
13 
28.9 
Stage A or E (Developing, or spent or resting) 
7 
3 
100.0 
1 
33.3 
Unidentified 
4 
1 
50.0 
0 
0.0 
6 
1 
50.0 
0 
0.0 
Total 
176 
