318 
Part III.— Ninth Annual Bepori 
west coast of Ireland, and described and figured the egg. Unfortunately 
no ripe male was secured. Mr Holt points out that the pale oil-globule 
sometimes shows a faint dull-yellowish coloration round the edge. He 
noticed that the zona was thrown into ridges like those of the lemon-dab. 
A considerable quantity of the eggs of the brill was procured by Mr 
Thomas Scott, F.L.S., off Montrose, about 7 p.m. on April 30, and, for 
want of better, fertilised with the milt of a turbot. Both brill and turbot 
were of average size. Mr Scott states that the germinal disc was faintly 
visible at 8 a.m. on the 1st May, and more distinctly so the same evening. 
On the morning of the 2nd May segmentation had commenced, and he 
accordingly sent on the ova to the St Andrews Marine Laboratory, where 
they were received at 3.30 the same day. 
In the evening the disc was in the biconvex stage. Next day (3rd) the 
germinal cavity appeared, and on the 4th May the embryonic shield was 
formed. The egg on the 6th May, when minutely inspected, resembled 
that of the lemon-dab, though in regard to size it is larger, the diameter 
being about '0555 of an inch, or 1*4097 mm., the contraction after preser- 
vation in spirit reducing the size to *048 or '0495 inch, and picric acid 
causing even greater diminution. The capsule {zona radiata) presents an 
irregular basket-like pattern, similar to that of the lemon-dab, with a slight 
sheen (PI. X. figs.l, 2). In many, moreover, a series of minute oil-globules 
formed a zone round the larger. The blastoderm of this date (6th May) 
has not quite enveloped the yolk (PI. XIII. fig. 1), and the majority of the 
eggs are unhealthy or dead. Even temporary examination in several 
instances sufficed to prove fatal, a rare occurrence with healthy eggs. The 
embryo is outlined, and the optic vesicles distinct. On the 7th the closure 
of the blastopore occurred, and next day Kupffer's v^esicle appeared. On 
the 12 th a considerable portion of the tail was free, and on the 13th one 
or two emerged, floating languidly on the surface. A few issued at 
intervals till the 15th May. On the whole, however, not more than 
twelve or fifteen were hatched out of the total number of eggs, and the 
vitality of these was low, since none survived more than two or three 
days. Professor Prince, who was at the Laboratory during my absence, 
kindly made drawings of the egg immediately before hatching and of the 
newly hatched larva (PI. XIII. figs. 2 and 3). The development of the 
brownish and black pigment on the trunk of the embryo in ovo is charac- 
teristic ; moreover, yellowish and black chromatophores exist in connection 
with the oil-globule, and the yolk has numerous yellowish pigment-specks. 
The black chromatophores on the head and body are stellate or ramose, 
and minute black grains occur in the eye. The skin of the marginal fin 
is glandular. 
Immediately after extrusion the young hybrid (PI. XIII. fig. 3) is about 
2*6 mm. in length, as measured by Professor Prince. The yolk-sac is large 
and rounded, with the oil-globule placed at the posterior border, and 
somewhat above the ventral edge. The head presents a normal appear- 
ance, and thus differs from the sketch of the supposed brill given by Dr 
Raffaele."^ The body and marginal fin have the usual disposition. The 
dorsum of the head has black and brown pigment-corpuscles, and the body 
is deeply tinted of the same characteristic brownish colour to the vertical 
caudal bar, bla'^k chromatophores being dotted all over the same region. 
The marginal fin has a patch of yellowish and brownish with a few black 
chromatophores just behind a line from the posterior bor' " " 
sac. About midway between the latter border and the 
patch of yellowish pigment with one or two black chroma 
dorsally and ventral ly, so that a kind of bar is forme 
* Op. cii,, tav. 4, fig. 18. 
