OVARY AND OVARIAN OVA IN CERTAIN MARINE FISHES. 103 



Emery figures a portion of an immature ovary as it appears 

 under a low power in the fresh condition. In the largest eggs, 

 scattered, highly refringent globules, exactly like those de- 

 scribed by me in the eggs of the sole, &c., have begun to 

 appear, and are identified by Emery as adipose globules. 

 Sections of later stages from material prepared with picro- 

 sulphuric acid are figured, in which the oil globules have become 

 larger by fusion, and the yolk globules are developing, the 

 latter forming an external layer, the former situated near to 

 the germinal vesicle. There is a diiFerence, however, to be 

 mentioned. In Fierasfer the eggs are not spherical, but 

 oval, and the germinal vesicle is situated nearer to one pole of 

 the oval than to the other. At the pole which is farthest from 

 the germinal vesicle the yolk globules are formed first, and the 

 vitelline nucleus is situated there also, so that the yolk glo- 

 bules are formed around it. The yolk layer during its increase 

 continues to be thickest at the same pole. 



Emery describes the course of development in the ovary 

 which culminates in the annual spawning. He found that 

 from the commencement of autumn to the end of spring, the 

 ovary contained transparent eggs only, of which the largest 

 contained a few small adipose globules, but no vitelline; in all 

 the ova the vitelline nucleus was still visible. As the time of 

 spawning — which extends over July, August, and September — 

 approached, the vitellus in the larger eggs was rapidly formed. 

 When the mature eggs had been discharged the ovary was 

 collapsed, it showed traces of haemorrhage in the form of 

 extravasated blood, or masses of pigment red or yellow in 

 colour, and besides young ova contained others which, not 

 having reached perfect maturity in time for the spawning 

 process, were not expelled, and were undergoing adipose 

 degeneration. 



Dr. Robert ScharfF published a paper on the development of 

 the egg in Teleosteans some years ago (this Journal, vol. 

 xxxviii), in which he refers especially to the ovarian eggs of 

 Trigla gurnard us. He discusses somewhat briefly the 

 formation of the yolk spherules and oil globules. His figures 



