FCETAL NUTRITION: THE PLACENTA 



475 



Glycogen is contained in the clecidual cells, but its variations 

 have not yet been investigated. It is of interest historically that 

 oxyhsemoglobin was demonstrated first in the umbilical vein of a 

 foetal guinea-pig by Schmidt. 1 The amounts of oxygen absorbed and 

 carbonic dioxide excreted are the same, weight for weight, as in the 

 fcetal rabbit (Bohr). (See above, p. 464.) 



Fat is widely distributed in the foetus, and Hof baur 2 has shown 

 that the fatty acid of a fat ingested by the mother guinea-pig may be 

 transmitted across the placenta to the foetuses. The mother was fed 

 on coco-nut oil which consists largely of triglycerides of laurinic and 



am 



FIG. 137. Implantation cavity of the guinea-pig. (Duval.) 



mes, Mesometrial (placenta) border ; I, lumen of uterus, re-established anti- 

 mesometrially ; d./:, decidua reflexa ; all, allantois ; am, amnion. 



inyristinic acids, and considerable quantities of laurinic acid were 

 afterwards found in this guinea-pig's foetuses (see p. 543). 



Beaver. The connecting membrane, or " Haftstiel," and the part 

 it plays in this animal have already been referred to (p. 423). 

 Another noteworthy feature is the abundance of erythrocytophagous 

 and leucocytophagous cells. There is no bleeding into the uterine 

 cavity, but the maternal capillaries, which are very numerous, abut 

 upon implanted megalokaryocytes and discharge the red corpuscles 

 directly into the trophoblast. The extravasated erythrocytes are all 

 ingested by megalokaryocytes. Migrating leucocytes in large numbers 

 are also absorbed by the large phagocytic cells. 



1 Schmidt, " Sauerstoffhamoglobin in Fotusherzblut," Cent. f. d. med. Wiss.. 

 J 874, No. xlvi. 



3 Hofbaur, Grnndzilge einer Biologic, der MensehHeken Plazenta, Leipzig, 1905. 



