342 
BULLETIN OF THE BUREAU OF FISHERIES 
thought by fishermen to be in breeding condition. At this time, however, they are 
much smaller than at the breeding season. Even in the fall the eggs are often bright 
yellow and the spermaries or milts are white. 
These organs are suspended from each side of the air bladder at the upper surface 
of the abdominal cavity by a thin membrane (figs. 23 and 24) , which forms the envel- 
oping membrane of the organ. In the male it completely envelops the spermary, but in 
the female the ovary is not completely covered by it. If, say in December, the 
ovaries of a smelt that would have spawned the next spring are carefully examined, 
it will be seen that the membrane forms the surface of the organ facing the median 
axis of the abdominal cavity and extends around and up for about one-third or more 
of what appears to be the other side of the ovary as it seems to be hanging in 
the abdominal cavity. There is thus a surface apparently not covered by the mem- 
brane. As a matter of fact the membrane is not a cover or envelope but is a part 
of the ovary, and the eggs are formed in crosswise folds of the ovarian membrane. 
As the eggs develop the ovaries enlarge and may be said to stretch (as do the 
spermaries also) and gradually come to almost fill the abdominal cavity. 
The edge of the membrane, which seems to limit the uncovered egg surface, 
continues backward from the posterior end of each ovary and is diverted to one side 
and is attached to the lateral wall of the abdominal cavity forming the lower surfaces 
of the egg channels, which unite in a common channel (figs. 22, 23, and 24 g ) near the 
outlet. Both of these channel membranes, which have been incorrectly termed 
“funnels,” when not containing eggs lie against the membrane of the air bladder, 
which forms the roof of the so-called “funnel.” 
The gravid ovaries fill all the space in the abdominal cavity not occupied by 
other viscera. Upon opening the fish from throat to vent along the median line ot 
the belly and laying the lateral walls aside, at first glance there appears to be one 
single mass of eggs, in front of which is the liver; posteriorly a small portion of the 
intestine may be visible. The greater portion of the egg mass is the anteriorly situ- 
ated left ovary, which extends from the liver to some distance beyond the base of 
the ventral fins (fig. 22 a ) . Placed closely to the posterior end of the left ovary is the 
right ovary (fig. 23 b), which extends nearly to the vent. The dividing line, which is 
often difficult to discern, beginning perhaps a little in advance of the ventral fins, 
extends obliquely from the right side (left as observed) backward to the left side (right 
as observed). Both ovaries are ventrally convex from side to side, and concave 
above, thus forming a broad, more or less triangular groove, in which anteriorly the 
stomach lies. The intestine, at first above the stomach, finally lies in the grooves 
of the left and right ovaries. These grooves are formed by the left ovary curving 
over so that the so-called “lower edge” is in contact, or nearly so, with the dorsal 
surface of the abdominal cavity on the right side, the left ovary curving in like 
manner in the reverse direction. 
The ovarian membrane is so thin that it is easily broken or rubbed off in exami- 
nation or handling, so that one may easily be deceived into believing that there is 
no membrane and that the eggs are free in the abdominal cavity. 
If the ovaries of a December smelt, previously mentioned, are compared with 
those of a gravid smelt in April, one is likely to wonder how the comparatively small 
