440 THE PHYSIOLOGY OF REPRODUCTION 



smaller size appears later in the lumen and wall of the implanta- 

 tion cavity. Jenkinson also recognised two groups, but assigned 



sym. 



Fig. 106. — Longitudinal section of the implantation cavity of the field- 

 mouse about the eighth day of pregnancy. (From Disse's "Die 

 Vergrbsserung der Eikammer bei der Feldmaus {Arvicola arvalis)," Arch, 

 f. mikr. Anat., vol. Ixviii., 1906.) 



p.l., placental pole ; mph, macrophages or giant-cells ; sym, uterine 

 symplasma ; /, blood lacuna. 



to them different origins, foetal in the " Eikammer " and 

 maternal in the decidua. 



All authorities agree that they are phagocytic. The tissue 



