FGETAL NUTRITION: THE PLACENTA 417 



vesicle is avillous but strongly folded, the ends of the ectodermal 

 cells are expanded like clubs, and their protoplasm becomes 

 coarsely reticular. Into the meshes the constituents of the 

 green pulpy mass, unaltered erythrocytes and haemoglobin or 

 its derivatives, are absorbed by phagocytosis. 



From the preceding account, it is clear that certain re- 





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e o.oo-' 



Fig. 99. — The labyrinth and the green border of the placenta of the dog at 

 the fortieth day of pregnancy. To the right are two lobules of the 

 angioplasmode which have reached the stage of complexity of the 

 labyrinthine lamellae : to the left is the green border, the cavities of 

 which, normally filled with blood, are indicated by a cross. (From 

 Duval's " Le Placenta des Carnassiers," Journ. de I'Anat, el dela Phys,, 

 1893.) 



1, 2, and 3, basal lamellae of the green border ; 4, basal lamella of lobule 

 of labyrinth. 



semblances and certain differences exist between Carnivora and 

 Ungulata in the composition of the embryo trophe. The most 

 notable difference in the zonary placenta is the absence of the 

 large amount of milky fluid which arises in the sheep from 

 the glandular secretion and the transudation of lymph. In 

 Carnivora the gland secretion is less important. Though the 

 deep parts of the glands which lie in the glandular layer may 



2d 



