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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. 



Esmarkii. — 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 luscus examined were mature. The 

 smallest male in the collection measured 16- 8cm., and the next in size 

 was 21cm., 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 luscus ripe in the Forth in March 

 and another in May. According to Heincke and Ehrenbaum luscus 

 spawns at Heligoland from (March?) April to August. 



O. 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 luscus. 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. 



