353 
during incubation in the common fowl. 
Fig. 5. The embryo in its amnion, and with its vesicle re- 
moved from the yelk, and represented in its natural position. 
The vesicle at this period forms an adhesion with the amnion 
at the lower extremity. Magnified 3 diameters. 
Fig. 6. The same embryo turned on its back, having on 
its right side a small portion of the vesicular, and on its left, 
of the areolar membrane, with the principal trunks of their 
blood-vessels. Magnified 3 diameters. 
Fig. 7. An egg , opened the seventh day after incubation. 
Natural size. 
Fig. 8. The embryo in its amnion, and with its vesicle 
removed from the yelk, and represented in its natural po- 
sition. The vesicle, which at this period covers entirely the 
embryo, is here turned downwards, and shows the increasing 
adhesion with the amnion. Magnified 2 diameters. 
Fig. 9. The same embryo extracted from its amnion, and 
turned upon its back, having on its right side a small portion 
of the vesicular, and on its left, of the areolar membrane, 
with the principal trunks of their blood-vessels. Magnified 
2 diameters. 
PLATE XXXVII. 
Fig. 1. An egg , opened 8 days after incubation. Natural 
size. 
Fig. 2 The embryo within its amnion, in its natural position, 
and with a portion of the vesicular and areolar membranes, 
with the principal trunks of their blood-vessels. Magnified 
2 diameters. 
Fig. 3. The same embryo turned on its back, having small 
portions of the vesicular and areolar membranes protruding 
from the enclosed part of the abdomen. Magnified 2 di- 
ameters. 
MDCCCXXII. 
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