

On 



t_j..j.L^A2miS^ 



TELEOSTEAX EGG.— Fig. 1. 

 Plate I. 



Figs, f, g, 1, m X 450 ; rest X 50. 



The sections in this and the following figures have been drawn with the help 

 of the Leitz Drawing Aj)paratus. 



Plaice— (a) i-cell stage; {hjc) 1-2-cell stage; {dlhllx) successive segmentation 

 stages during the 1st and in the case of (A) the '2ad day. 



Cod— (e/J) segmentation stages at beginning and end of 1st day ; [fjg) indicate 

 the development of vacuoles between adjacent cells ; (Z) margin and adjoining 

 ventral portions of blastodisc at end of 2nd day ; {m) vertical division of cell 

 in lower layer, end of 2nd day. 



