oj the fishery Board for Scotland. 119 



XXII. The Position of the Ureter with respect to the Swim-bladdeb. 



In certain of the species there appeared to be some indication that a 

 sexual difference might be found in the character. Although the ureter 

 was found in each sex on both sides of the swim-bladder, still there 

 seemed to be a tendency for the majority of cases in each sex to be on 

 one side. 



In callarias the ureter leaves the kidney at the first hfemal arch ; 



it pierces an extension of the wall of the swim-bladder. 

 In virens the ureter was found to leave the kidney at the second 



vertebra in front of the first haemal arch. 

 In pollachius it left at the junction of the first and second 



vertebrse in front of the first haemal arch. 

 In argenteus the ureter was median just behind the swim-bladder, 



which ended one vertebra in front of the first haemal arch. 

 In saida the ureter issued behind the end of the swim-bladder, i.e., 



at the first haemal arch. 



XXIII. The Ovary. 



There is much difference between the species in the shape of the 

 ovary. This organ varies in the comparative lengths of the 

 anterior and posterior lobes. In some the posterior lobes of 

 the ovary are fused in part or in their whole extent. 



Then in side view the ovary may be distinctly triangular in shape, 

 exhibiting a great increase in dorso-ventral thickness at the 

 oviduct, or the ovary may show very little taper from the 

 middle to either end. 



For this purpoae large roes of each species have been examined. 

 They are ovaries containing yolked eggs. The ovary of 

 virens was, however, unripe, and for esmarki a small unripe 

 ovary probably lately spent has been drawn. I did not have 

 an ovary of poutassou sufficiently large. 



In side view the following are markedly triangular in shape : — 

 Pollachius, fig. 94 ; virens, fig. 13 ; luscus, fig. 73 ; minutus, 

 fig. 77 ; esmarki, fig. 97. 



