THE ACTIVATION OF UNFERTILIZED EGGS 99 



TABLE XVII (Continued) 



The Development of Unfertilized Rabbit Ova in Culture. (From 



Pincus, 1930) 



Age of Ova 



(Hours 

 AFTER Cop- 

 ulation) 



13 15 

 13 35 



Num- 

 ber 



Medium 



RPCE 

 RPRE 



RPRE 



RPRE 

 RPCE 



CPCE 



RPRE 



RPCE 



RPCE 



CPCE 

 RPCE 



Exam- 

 ined 

 (Hours 

 IN Cul- 

 ture) 



47 



43 



25 



27 



30 



27 



22 



23 



48 

 26 



Description 



2 — unsegmented 

 1—16 to 20 cells 

 1 — in 2 cells and 2 to 



5 polar bodies 

 3 — with about 5 polar 



bodies 

 7 — unsegmented 

 2 — unsegmented 

 1 — in 4 regular cells 



and 2 polar bodies 

 1 — in morula 

 1 — unsegmented 

 2 — in 3 regular cells 

 2 — in 4 regular cells 

 2— in 36 to 40 regular 



cells 

 2 — in about 4 cells 



regular 

 1 — with multiple polar 



bodies 

 1 — unsegmented 

 1 — in 4 regular cells 

 1 — in about 16 cells 

 2 — in 1 very large cell 



and 10 to 12 small 



ones 

 2 — in about 16 cells 

 1— in 32 to 48 cells 

 1 — in 2 regular cells 



and 2 polar bodies 

 1 — in 3 to 4 large 



cells and 10 small 



cells 

 1 — in 1 large cell and 

 16 small cells 

 2 — no segmentation 

 1 — 2 large, 2 small 



cells and several 



polar bodies 

 1 — in 16 very regular 



cells 

 2— in 20 to 32 cells 



Num- 

 ber Di- 

 vided 



Num- 

 ber 

 Undi- 

 vided 



(C = Chicken. 



R = Rabbit. 



P = Plasma. 



E = Embryo Extract.) 



