106 J. T. CUNNINGHAM. 



SO prepared taken from a specimen obtained in Grimsby 

 market on April 26th, and from portions of an ovary preserved 

 directly after the death of the fish at sea on July 22nd. Com- 

 parison of the two shows that the material from the market 

 specimen is in fairly good condition, the vitelline elements 

 being well preserved. The principal defect due to the stale- 

 ness of the material is the contraction of the protoplasm of the 

 younger yolkless eggs, and the presence of a layer of granular 

 matter around them. 



The yolk globules are first recognisable in eggs '23 mm. in 

 diameter, and have the form of minute granules situated near 

 the surface of the ovum. The yolk granules can be distin- 

 guished from the oil globules by the fact that they are solid. 

 The process of preparation coagulates the yolk substance, and 

 it retains the staining matter used to a greater or less degree, 

 while the oil globules are not coagulated but dissolved, and 

 the spaces they occupied appear merely as empty vacuoles. 

 At the stage now under consideration there is a zone of such 

 vacuoles of rather large size separated by a zone of relatively 

 homogeneous protoplasm, both from the surface of the nucleus 

 and from the yolk zone. This stage corresponds to that of 

 fifj-. 3j among those representing the appearance in the fresh 

 condition. 



Since in earlier stages, before the appearance of yolk 

 granules, oil globules occur quite close to the wall of the 

 o-erminal vesicle, it would seem that some change has occurred 

 which has driven them outwards. This might be explained 

 by supposing that new protoplasm was forming in the neigh- 

 bourhood of the germinal vesicle. The egg is rapidly increas- 

 ing in size, and it seems probable enough that the deposit of 

 food material is taking place at the periphery in the older 

 protoplasm, while the growth of the protoplasm is taking 

 place in the neighbourhood of the germinal vesicle. The zone 

 around the latter, however, has a granular appearance, and 

 contains I believe very numerous but extremely minute glo- 

 bules of oil, although they cannot be recognised with certainty 

 as such in the sections. 



