320 
Part III. — Ninth Annual Report 
Additional remarks are made in the Researches, where an account 
of the late larval condition, with a coloured figure by Professor Prince 
occurs. It it there stated that the larval fish is comparatively large, 
resembling in certain respects the larval plaice. 
It is remarkable that since the trawling expeditions no ripe specimen 
of the long rough dab has been under examination at the Laboratory, 
though it occurs not infrequently in the bay, and is widely distributed 
elsewhere ; indeed, when the liners are at work off the Carr in the early 
part of the year many are caught. Mr Holt has now, at any rate, proved 
the identity of the egg named Pleuronectid B with that issuing from 
the long rough dab, and thus has done good service in clearing up the 
obscurity. In no collection made with the tow-nets in the ordinary way 
have these eggs been in greater numbers than on Liston's Bank, east of 
the Island of May, as shown in the detailed results of the ' Garland's ' work 
in this department. 
In the Seventh Annual Keport of the Board, 1889, Part III. p. 191, a 
summary of the condition of 821 specimens of the long rough dab is 
given by Professor Ewart and Dr Fulton, from which it appears that in the 
Forth some were quite mature in December, more in January, and still 
more in February and March, while in April and May ripe specimens 
occasionally occurred. In the Moray Firth, again, ripe examples occurred 
plentifully in January and February. My own experience in regard to 
the occurrence and distribution of the characteristic ova is that they have 
hitherto been found chiefly in March, rarely one or two in February, and 
that in all probability, though nearly ripe, none are discharged before 
January. The maximum period seems to be in March and beginning of 
April. The expansion of the ova probably takes place shortly before 
extrusion, since only one or two of those preserved in March 1884 (from 
the ovary) show an indication of this condition. 
Couch, who appears to have considered this a somewhat rare fish in his 
neighbourhood, states that it spawns in May and June ; while Malm 
gives February and March as the spawning period. 
3. On an Unknown Egg and Larva. 
In the bottom tow-net of the 9th Marcli, in St Andrews Bay, an 
extremely buoyant egg, not hitherto described, appeared, and for some 
weeks it occurred occasionally. It is a comparatively small egg, measuring 
about •032 inches, with a distinct oil-globule, and frequently in addition 
another definite pale area, slightly refracting the light, and apparently 
due to a differentiation of the yolk (PI. XII. fig. 1). In eggs with an 
early blastoderm {e.g., small-celled stage) the oleaginous area appears 
to be near the animal pole. In manipulating this egg, the oleaginous 
area in some got under the embryo and kept the egg floating with the 
embryo upward, and the oil-globule downward. In dead eggs the area 
sometimes breaks up into a number of spheres. In a single abnormal 
egg the oil-globule occurred in a lateral position. As a rule, pigment 
appears in connection with (under) the oil-globule, and in some advanced 
forms minute round vesicles occur on the surface, and occasionally one or 
two large pale vesicles at the margin. In one specimen two chromato- 
phores appeared in the area of the large vesicle in front of the oil- 
globule, instead of in that of the oil-globule itself ; the yolk is not per- 
fectly transparent, but is minutely streaked with short wavy touches. 
It has not yet been determined whether these are superficial or general. 
* Mlntosh and Prince, p. 853, pi. x. fig. 8, pi. xiii. fig. 3, and pi. xviii. fig. 2. 
