344 
BULLETIN OF THE BUREAU OF FISHERIES 
December organ could produce as many eggs as are present in April. The fact ap- 
pears to be that as the eggs develop and increase in size the outer ovarian membrane 
and the egg-bearing cross partitions are so stretched downward that, following the 
contour of the abdominal wall, they turn up and approach the dorsal surface of the 
abdominal cavity, so that what may be regarded as the bottom of the ovary is some- 
times nearly on a level with the top. The “ top,” or that portion of each ovary that 
is not invested with adherent membrane, consists of a narrow dorsal area that is 
tipped in against the suspending membrane of the ovary. In these passages, formed 
by the investing membranes, the eggs pass backward into the egg channels previously 
mentioned. Here again one may wonder how the eggs manage to find their way into- 
these channels from such apparently distorted ovaries. But the problem is not quite 
as difficult as it would be to try to account for their manner of exit if they were lying 
loose in the abdominal cavity. At least it may be suggested that near the posterior 
end of the ovary and close to the mouth of the egg channel, as the eggs pass into the 
channel, the ovarian membranes and cross partitions shrink or contract so that the eggs 
are brought necessarily from the “bottom” and the front into line with the channel. 
If the eggs are set free in the abdominal cavity, as has been claimed, there appears 
to be no conceivable way by which they could be extruded, for the reason that, as 
previously stated, before the eggs of the left ovary have entered the egg channel the 
gravid right ovary presses the left egg-channel membrane (fig. 23 g ) against the air 
bladder and left abdominal wall. 
So it seems that the eggs of the small right ovary must ripen and be deposited 
before the eggs of the left ovary can fill its egg channel. As the eggs of the left ovary 
enter its egg channel the empty right ovary is compressed between the distented left 
egg channel and the right abdominal wall. As the right egg channel and ovary are 
emptied the left egg channel becomes entirely filled with eggs, and these, with the 
remaining eggs in the left ovary, have the appearance of a single continuous ovary. 
When both ovaries are emptied the collapsed organs have contracted so that the left 
is again small and considerably in advance of the right ovary. Both contain visible 
though minute eggs, which constitute the future crop. 
FECUNDITY 
The number of eggs deposited by an individual depends upon its size, varying from 
a few hundred to thousands. According to Smitt (1895), the number of eggs carried 
by a female European smelt 18 to 20 centimeters (about 7 to 7.8 inches) long was 
estimated by Nor back at 50,000 and by Olson at 36,000. Mather (1885) said that 
he took from a “dead female” 30,000 eggs, and Mr. Walters took about 50,000 
from a “ weak female.” In 1887 he wrote that the little smelt carries from 30,000 to 
60,000 or perhaps more eggs, and that from 100 ripe females of good size probably 
5,000,000 eggs could be obtained. 
A fresh-water smelt 4% inches long received by the present writer from Toddy 
Pond, East Orland, Me., was found by actual count to contain 5,893 eggs. 
In a letter dated March 27, 1909, Superintendent Race of the Bureau of Fisheries' 
Green Lake (Me.) station, stated that from March 8 to March 19, inclusive, 425 
large smelts had been collected; of which, so far as could be ascertained, 200 were 
