262 



MARKETABLE BRITISH MARINE FISHES 



a single oil globule in the yolk, and this has a pale ochre 

 colour. The egg-membrane is close to the yolk, as in most 

 buoyant eggs. It was found that a few days after fertilisation 



the eggs sank to the bottom 

 of the jar, although they were 

 studied on board a fishing vessel 

 in the open North Sea, so that 

 the later development takes 

 place nearer the bottom than 

 the surface of the sea. 



The larvj£ were hatched out 

 seven to nine days after fertili- 

 sation. They were small, mea- 

 suring only 2'i4 mm. in length 

 (a little more than yV inch), 

 and the tail portion is a good 

 deal shorter than the yolk-sac 

 (Fig. 12 1). Neither mouth nor 

 anus is formed, the fin-membrane is narrow, and generally 

 the larva is less developed than that of the plaice or 

 flounder when first hatched. The coloured pigment specks 

 by reflected light are a red-orange, and when seen b)- the 



Fig. 1 20. — Egg of the Turbot, alive 

 and magnified ; after Mcintosh. 



Fig. 121. — Larva of Turbot newly-hatched ; after Holt. 



light passing through are much the same but more inclined 

 to crimson. None of the larvae lived more than a few 

 days after hatching, but a good series of older stages was 

 obtained by Mr. Holt from the North Sea, by means of the tow- 



