130 Part III.—Twenty-fourth Annual Report 
The Ureter varies in position with respect to the swim-bladder. It 
may come down from the kidney on either side of the swim-bladder 
Its position has been noted in a number of specimens, 
Luscus.—Out of 11 cases the ureter was on the left in 7, and on the 
right in 4. 
Minutus.—Out of 39 cases the ureter was on the left in 14, and on the 
right in 25. 
Esmarkit.—Out of 53 cases the ureter was on the left in 21, and on 
the right of the swim-bladder in 32. 
Reproduction. 
G. luscus.—All the specimens of /wsews examined were mature. The 
smallest male in the collection measured 16°8cm., and the next in size 
was 2lem., while the smallest female was 25cm. long. Fifty-three 
specimens were examined in all. 
The reproductive organs ripen early in the spring. 
In January, of the males (24 in number), 22 had large testes, and 2 
had developing smaller testes ; of 18 females, 17 had large ovaries, and 
one had a smaller developing ovary. 
In February 1 male and 3 females were ripe, and 3 males had large 
testes. In 1 female there was a developing ovary. 
In March 1 female was ripe, and another had a developing ovary. 
In May the one specimen examined was a spent female. 
A female measuring 24cm. obtained in June had a small ovary. 
The ovary is regarded as ripe when it contains transparent eggs. 
These are to be seen through the skin of the ovary scattered over the 
ovary, giving the condition known as the ‘‘ beaded roe.” The ovary may 
thus be labelled ripe before it is actually running. The large ovaries are 
white ‘hard roes.” 
M‘Intosh and Masterman give the spawning time of this form as 
January-—February. Fulton found a Juscus ripe in the Forth in March 
and another in May. According to Heincke and Ehrenbaum Juscus 
spawns at Heligoland from (March?) April to August. 
G. minutus. All the fishes of this species of which the condition of 
the reproductive organs has been recorded were mature. The smallest 
male and female measured 15cm., and above that size mature males were 
obtained at each centimetre up to the length of 22cm. No male larger 
than that was found. Mature females were found at every centimetre of 
length from 15cm. up to 29cm., with the exception of 28cm., at which 
size no minutus was obtained. The evidence therefore points to the 
conclusion that minutus becomes mature both in the male and female at 
or before reaching a size of 15cm. in length. 
The reproductive organs of minutus ripen about the same time of the 
year, but a little later than in /uscus. Ripe females of minutus were not 
met with till March. 
In December 5 females had small developing ovaries. 
In January 1 male was ripe, 10 males had large testes, while 1 male 
had a small developing testis. Thirty females had large ovaries, and 22 
had small developing ovaries. 
In February 16 males had large testes, 73 females had large ovaries, 
and 5 females had small developing ovaries. 
In March 6 males had nearly ripe testes, 2 females were ripe, and 55 
females had large ovaries. In this month nearly all the ovaries were 
large, white ‘hard roes.” 
In May 2 males had nearly ripe testes, and 48 females were ripe. 
