PLATE 11 
EXPLANATION OF FIGURES 
Photomicrographs taken alive by reflected light in Ringer’s solution; except 
fig. 2. Figs. 1 to 4, bilaminar blastocysts; figs. 5 to 10, unfertilized eggs. Mag- 
nification, X 8, except fig. 5. 
1 Litter No. 294, mostly abnormal blastocysts with still largely unilaminar 
walls (compare fig. 2, pl. 6). 
2 Part of litter No. 290’, photographed a few minutes after immersion in 
Hill’s fixing fluid; embryonic area is well seen. 
3 Litter No. 290’; bilaminar blastocysts (compare fig. 2, pl. 6). 
4 Litter No. 294’ (interval 341 hours; compare fig. 1); mostly abnormal 
bilaminar blastocysts. 
5 Litter No. 415; unfertilized eggs in early stage of fragmentation; shows 
false ‘1-celled,’ ‘2-celled,’ and ‘4-celled’ eggs. 
6 Litter No. 318; early eggs in fragmentation; note that the ovum proper is 
no longer spherical. 
7 Litter No. 303, with opaque albumen and fragmenting ova. 
8 Litter No. 297; old fragmenting eggs with white concretions on shell mem- 
brane. 
9 Four degeneration eggs that accompanied foetuses one day before birth; 
Litter No. 321’. 
10 Litter No. 332; degenerating eggs nine or ten days old. 
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