74 MAKKKTAI5LE BRITISH MARINE FISHES 



side. The organs are seen in their natural position. L is 

 the liver with the large globular gall-bladder attached to it. G 

 is the gut or intestine, bent upon itself three times so as to lie in 

 four lengths side by side. Behind the gut is seen the hinder 

 part of the hard roe, R, the front part being covered and con- 

 cealed beneath the gut. Fig. 35 shows what is seen when the 

 gut and the liver are removed. Nearly the whole length of the 

 roe is now visible, ending in front in a tube which joins another 

 tube from the roe of the lower side of the fish to open on the 

 edge of the body behind the head. The roe on each side rests 

 against a series of bones lying in the middle region of the body. 



When a male sole is cut open in a similar manner, as seen in 

 Fig. 36, the intestine and the liver are seen as in the female, but 

 no roe is visible. In fact until a few years ago a deal of mystery 

 hung over the question of the male sole, and it was even doubt- 

 ful to fishermen and others whether there were two sexes in the 

 sole at all. The truth is that the soft roes of the sole are very 

 small. Their size and position arc shown in Fig. 37, representing 

 the appearance of the belly cavity after the liver and intestines 

 have been taken out. The soft roes or milts, indicated by the 

 letter M, are small oval white bodies lying at the back of the 

 central cavity, and connected with the edge of the body by two 

 cords, in which the milt is conducted to the exterior. The ex- 

 ternal opening is on the upper side of the fish just behind the 

 opening of the gut. 



In the cod, haddock, and other fishes of the cod family the 

 hard roes are short, thick bags, joined together at their hinder 

 ends and placed at the back of the belly cavity. The soft rocs 

 have a very different appearance to that seen in the majority of 

 fishes. They are white narrow frills, in a position correspond- 

 ing to that of the ovaries. They consist of a pair of narrow 

 thickened bands attached by thin membranes to the back of the 

 cavity : they are very much longer than the attached edges of 

 these membranes and consequently are thrown into zigzag folds. 



Dr. Fulton has investigated, besides the comparative fecundity 

 of the sea fishes, the proportions between the numbers and .-i/.es 

 of the two sexes. He did this by study of the records of the 

 and sexes of all the fish captured in the trawl of the inves- 

 tigation steamer of the Scotch Fishery Board, supplemented by 

 the examination of numbers of certain kinds of fish captured in 



