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Part III. — Seventh Annual Report 



pigment corpuscles appear to pass in front of the yolk. The cells of 

 the notochord are small. The anus is distinct. 



The arrangement of the pigment and other features resemble those of 

 the plaice, and when the larval fish is a few days older a greenish lustre 

 pervades the eyes. 



It is noteworthy that these eggs did not present the somewhat rough — 

 almost rasp-like — appearance under both lens and microscope which is so 

 characteristic of the ova of plaice removed from the ripe female, and 

 which thus have a slightly silvery sheen in a bright light. 



Ovum with Large Perivitelline Space. — Towards the end of April the 

 large transparent eggs (with wide perivitelline space) were tolerably 

 numerous, about a dozen being got in a haul amongst the eggs of cod, 

 plaice, rockling, &c. Two sizes of these occur in the spirit-prepar- 

 ations, but such may be due to entrance of water into the perivitelline 

 space, to a greater extent in some than in others. 



Other ova become opaque when put in spirit, since the yolk fills the 

 space, whereas in these only the embryo with its yolk-sac, or the small 

 central yolk with the blastoderm, does. It has not yet been determined 

 whether the ovum when shed has the same characters as when captured 

 in the nets, or whether the perivitelline space largely increases by 

 imbibition. 



Dab. — Ova of this species were obtained early in April as well as towards 

 the close of the month. Hensen also found these eggs in the Baltic 

 towards the end of April. The larval-dab is about o^th of an iuch in 

 length, and furnished with distinct lemon-yellow (or amber) pigment- 

 specks in the form of two lateral bands. At the end of a week the 

 pigment has increased, and the eyes are blackish. The mouth has 

 opened, but not the anus. Three or four days later the eyes present a 

 greenish iridescence, the anus has opened, the yolk-sac has almost 

 disappeared, and the pigment generally has increased, 'large stellate 

 ' black spots extending over the eyes, otocystic and hepatic regions to 

 ' the anus, and along the dorsum and upper margin of the caudal trunk. 

 ' Crescentic yellow pigment-patches appear in the caudal membrane.' * 



Flounder. — An ovum resembling that of this species presented itself on 

 9th April in considerable numbers, and once or twice thereafter till the 

 26th of April. Kipe forms are abundant from the middle of March 

 onwards. Hensen found the eggs of the flounder in the Baltic towards 

 the end of April. 



Mutter's Topknot. — A female with some ripe ova was procured in the 

 middle of May. The pelagic ovum has an oil-globule, 



Turbot. — Ova apparently of this form were obtained at the surface 

 9th July 1884, 47 miles E. by S. off the Isle of May, and at the same 

 time ripe females were observed. 



Young stages of the turbot were procured in considerable numbers off 

 the Isle of May in August. 



Solea. — From the 20th May to the 6th of July, in various parts of the 

 Bay, a few ova, measuring '045 inch in diameter, were almost daily captured 

 in the mid-water and bottom-nets along with some of the gurnard. They 

 are characterised by a more or less complete ring of groups of minute oil- 

 globules, which vary in appearauce according as the light is transmitted 

 or reflected, being faintly straw coloured under the former, yellowish- 

 white under the latter. The zona is tough and very distinctly punctate, 

 even more so than that of the plaice and in one instance flattened 

 papillae occurred on it, so that it had a scabrous appearance. The 



* E. E. Prince, Ann. Nat. Hist., May 1886, p. 459. 



