of the Fishery Board for Scotland. 



245 



cured by the laboratory attendant 160 miles E. by N. of Aberdeen (PI. X. 

 tig. 6). The embryo was well advanced on the 11th, and was tinted 

 yellowish from the chromatophores. A few finely ramose black specks 

 also occurred on the yolk. 



The following day the yellowish pigment was more abundant, and the 

 yolk somewhat less. The pectorals are budding out, and a large 

 Kiipffer's vesicle appears, though the tail has a broad marginal fin and 

 extends much beyond the yolk, which has a few yellow chromatophores. 

 Minute black specks occur amongst the yellow in the caudal region. 

 The otocysts have two otoliths. The egg-capsule (zona radiata) shows 

 very faint wrinkles, much less marked than in the lemon-dab. 



The larval fish has numerous yellow chromatophores over the head, 

 body, and tail, with a few on the yolk-sac (PI. X. fig. 7), and minute 

 black specks are also present. The otocysts are small. 



The relationships of this form are at present unknown. 



7. On an Unknown Pelagic Egg with a considerable Perivitelline 



Space and a Yellowish Embryo. 



In the same area. 160 miles E. by N. of Aberdeen, an egg (PI. X. 

 fig. 8) varying from 1*2192 mm. to 1*2954 mm. was obtained the second 

 week in June, the embryo on the 12th having the tail slightly free from 

 the yolk, ami with yellowish chromatophores generally distributed. 



The proportionally large size of the embryo is noteworthy (PI. X. 

 fig. 9), and well seen in a lateral view. A few yellow chromatophores are 

 also present on the yolk. On the 12th no action of the heart had yet 

 occurred. 



The embryos (PI. XII. fig. 3) which were hatched on the 16th June 

 are about 3 mm. in length, or slightly less. The head, body, and yolk- 

 sac are marked with bright gamboge-yellow chromatophores, and the 

 dorsal marginal fin, especially about its middle third, has many pigment- 

 corpuscles of the same colour, while some also appear on the ventral mar- 

 ginal fin. A few finely ramose black chromatophores are scattered over 

 the yolk-sac. The eyes have only yellow pigment, which is arranged in 

 a somewhat radiate manner. The notochord is multicolumnar. The 

 rectum is near the margin, but is still occluded. In the specimen figured 

 a clear vesicle lay under the trunk above the yolk-sac. 



One larval fish remained alive till the 19th June (Plate XII. fig. 4), 

 but the trunk was curved. The pectorals had much increased in size, 

 and the yellow pigment was more abundant on the head and other parts. 

 A broad band of the same pigment occurs on the ventral surface of the 

 yolk, a patch on the body just behind the yolk-sac. two others on the 

 caudal region, while at the tip of the tail, which is curved in the sketch, 

 are two patches of the same colour. The only black pigment visible is 

 a slight ring round each lens. An air-bladder seems to be developed. 



8. On an Egg 1*2954 mm. in diameter, with an Oil-globule *1905 in 



diameter. 



Likewise from the foregoing area comes an egg of 1*2954 mm. in 

 diameter (PI. IX. fig. 8), with an oil-globule *1905 in diameter, — that is, 

 somewhat larger than the egg of the mackerel, which Cunningham gives 

 as 1*22 mm. The zona is very delicate, and the micropyle a simple 

 depression. The yolk presents a finely reticulated surface (from the 

 blastoderm — as in the long rough dab?). The spaces are slightly 

 hexagonal, and somewhat resemble the cortical yolk-segments of Solea 

 lutea. They seem to be genuine reticulations, but they may be only 

 superficial, or in a double line round the yolk. The oil-globule had a few 

 small spheres of oil attached to it, and is pale under a lens, but assumes 

 a smoky hue under the microscope. 



