338 THE FLOUNDER FAMILY. 



about midway between the vent and the tip of the tail, behind 

 which the caudal region is translucent. In all these features it 

 thus closely approaches its ally, the tnrbot. 



Mr Holt in 1890 procured a ripe female off the west coast 

 of Ireland on the 16th June, but no male could be obtained. 

 He pointed out that the pale oil-globule sometimes presented a 

 faint dull yellowish coloration round the edge, and that the 

 capsule was thrown into ridges like those of the lemon-dab. 

 He considers that the spawning-period is from April to the end 

 of July. He again procured ripe females in the same region 1 

 and fertilized the eggs with milt of the dab, but they did not 

 survive. He gives the dimension at 1'43, and the oil-globule 

 24 to -27 mm. Canu has also successfully hatched the eggs of 

 this species, which he found pelagic from March to July. 

 Ehrenbaum 2 has recently given a careful summary of the 

 knowledge on the subject with additional observations of his own. 



On the 30th April, 1891, a considerable number of the eggs 

 of the brill (Plate IV, fig. 1) were obtained off Montrose by 

 Mr Thomas Scott, F.L.S., the able and indefatigable naturalist 

 on the staff of the Fishery Board, and fertilized at 7 p.m. with 

 the milt of a male turbot, as no male brill was procurable. 

 Both parents were of average size. Scott observed that the 

 germinal disc was faintly visible at 8 a.m. on the 1st May, and 

 more distinctly the same evening. On the morning of the 

 2nd May segmentation had commenced, and he forwarded the 

 eggs to the St Andrews Marine Laboratory, which they reached 

 at 3.30 the same day 3 . 



In the evening the disc was in the biconvex stage. Next 

 day, 3rd May, the germinal cavity appeared (Plate IV, fig. 2), 

 and on the 4th May the embryonic shield had formed. The 

 egg on the 6th May (that is on the sixth day after fertilization) 

 resembled that of the lemon-dab, though in regard to size it was 

 larger, the diameter being about '0555 inch or 14097 mm., the 

 contraction after preservation in spirit reducing the size to '048 

 or '0495 inch, and picric acid causing even greater diminution. 



1 Op. cit. July 1893, p. 70. 



-' Op. cit. p. 291, Taf. vi. f. 22-24, 1896. 



3 W. C. M., 3th Ann. Pept. ,<?. F. P,., p. 317, PI. XIII. 



