330 THE FLOUNDER FAMILY. 



bore the journey and the heat more satisfactorily, and pre- 

 sented at the 24th hour, viz., about 5 p.m. on the 22nd, the 

 germinal cavity and shield. As the embryo became outlined 

 next day (23rd) a tendency to the formation of numerous large 

 vesicles at the ordinary site of Kupffer's, as well as extending 

 forward along the body in groups, was a conspicuous feature. 

 How far this condition was due to the vicissitudes the eggs had 

 encountered is an open question, but it was pronounced. On 

 the 24th June, the embryo was distinctly outlined — with optic 

 vesicles, lenses, cardiac thickening, and other features, while the 

 large vesicles above-mentioned were fewer. Moreover, in some 

 a series of chromatophores were thickly dotted along the trunk, 

 and a few over the brain, but no colour was yet visible under a 

 lens, though the embryo was indicated by a distinct opacity. 



On the 25th, the eggs (Plate III, fig. 24) presented a slightly 

 reddish hue under a lens. It was also interesting to note that 

 the diameter of some of them had increased in the direction of 

 the long axis of the embryo so that they were ovoid. The head 

 and body were studded with rounded, reddish (ruby-red by 

 transmitted light) chromatophores, some however, being only 

 slightly tinted. They likewise extended over part of the yolk. 

 The protoplasmic investment of the oil-globule had a few black 

 specks. 



Next day the pigment-corpuscles had a deeper ruby-red, 

 and black chromatophores had also appeared. The pectoral 

 expansions were distinct, the vesicles had vanished from the 

 ventral aspect of the trunk, while the tail was longer and had 

 a few black chromatophores near the tip. The black pigment 

 at the oil-globule had increased. Only a few red and one or two 

 black chromatophores were present on the minutely vesicular 

 yolk-sac. The black corpuscles seemed to form a band along 

 the edge of the body superiorly and inferiorly. On the 27th 

 June, the colour under a lens was brick-red — from the branch- 

 ing of the red and black chromatophores. The eyes were 

 somewhat darker, and the yolk had still further diminished. 



Most of the eggs hatched about the sixth or seventh 

 day, the same period being menti<jued by Holt, the larval 

 turbot between the first and second daj-s having the aspect 



