BiOELow. — Developmeut of Lepas. 



PLATE 4. 



Figures drawn from transparent preparations of entire eggs. Vegetative pole 

 at tlie left in lateral views. 



Fig. 31. Egg viewed from animal pole. Late anaphase of second cleavage. 



Fig. 32. Four-cell stage. Nuclei in " resting " phase. Egg viewed from animal 



pole. 

 Fig. 33. Same egg viewed laterally. Yolk at vegetative pole of cell d"^. 

 Fig. 34. Four-cell stage during tliird cleavage. Viewed from animal pole. 

 Fig. 35. Same egg from vegetative pole. Oil spherules of the 3 oik near the 



surface. 

 Fig. 36. Same egg in lateral view. 

 Fig. 37. Eight-cell stage from animal pole. All nuclei are in " resting " phase. 



Second polar cell covered in by the meeting of a*'^ and c*"^. 

 Fig. 38. Same egg from vegetative pole. Oil spiierules near lower surface of j'olk- 



cell. Cells of quadrant I (b^-^, b'^-'^) stippled. 



