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Part III. — Ttcentieth Annual Report 



The dorsum of head and body is of a deep blacTc colour, which has a 

 green tinge. The belly and lower part of the sides are white. There 

 is a golden sheen over the belly and the white parts of the side. The 

 ventral fins are coloured white and pink. The lateral line is a broad 

 white streak in its whole length. 



Lythe. — Two lythe measuring 73 cm. male, and 39*8 cm. female, were 

 examined immediately after capture. 



The dorsum is of a dark olive colour. This colouration does not 

 extend further down the sides of the abdomen than the highest part of 

 the lateral Hue. The sides below that level are whitish. Behind the 

 anus the dark olive colour gradually envelops the whole side. 



A golden network is spread over the dorsum and down over part of 

 the white side. 



The lateral line is dark and not prominent. 



The above descriptions of the colours of the three species agree well 

 with those given in Smitt's "Scaudiuavian Fishes." 



Anatomical Difference — Urinary Bladder. 



In the cod there are two lobes to the urinary bladder : in the saithe 

 and lythe the urinary bladder has no lobes. 



The ureter leaves the kidney at a point well behind the level of the 

 anus. It passes down on one side of the swim bladder, and is con- 

 tinued forward lo dilate into the urinary bladder close to the rectum. 

 The ureter does not always pass down on the same side of the swim 

 bladder. 



Cod. — Of 5 males examined, the ureter was in two cases on the light 

 side of the swim bladder, and in three, on the left side of the same. 



Of 5 female cod, in three cases it was on the right side, and in two 

 on the left. 



Saithe. — Of 8 males, in five the ureter was on the right side, and in 

 three on the left. 



Of 4 females, it was in one on the right side, and in three on the left 

 side. 



Lythe. — Of seven males, the ureter came down on the right side of 

 the swim bladder in two cases, and in five cases on the left side. 



Of 19 females, it was in fourteen cases on the right side, and in five 

 cases on the left side. 



These figures will be more readily followed in the accompanying 

 Table. 



The number of specimens examined is small, but they indicate that in 

 the lythe the ureter in the male is most frequently to be found on the 

 left side of the swim bladder, whereas in the female it is usually on the 

 right side of that organ. In the case of the saithe the opposite would 

 seem to be the condition, while in the cod the very insufficient data show 

 a tendency towards the arrangement in the lythe. 



