FCETAL NUTRITION: THE PLACENTA 



475 



(Glycogen is contaiueil in the decidual cells, Imt its variations 

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

 oxyhccmoglol lin was demonstrated first in the umbilical vein of a 

 fcetal guinea-pig by Sclimidt.^ The amounts of oxygen absorbed and 

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

 foetal rabbit (Bohr). (See al)ove, p. 464.) 



Fat is widely distributed in the tVetus, and Hof baur - has shown 

 that the fatty acid of a fat ingested l:>y the motlier guinea-pig may be 

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

 on coc<j-nut oil which consists largely of triglycerides of laurinic and 



, mes 





am 



■i 'f;*** bv«««*. w«« V**^# »•* ? 



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



nie.v, Mesometrial (placenta) border ; /, lumen of uterus, re-established anti- 

 mesometrially ; i!.r., decidua reflexa ; i^/I, allantois ; am, amnion. 



myristinic acids, and consideralile quantities i>f laurinic acid were 

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



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

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

 Another iroteworthy feature is the abundance of erythrocytophagoiis 

 and leucocytopliagous cells. There is w) bleeding into the uterine 

 cavity, but the maternal capillaries, whiclr are ^'ery numerous, abut 

 upon implanted megalokaryoc}-tes and discliarge the red corpuscles 

 directly into the tropholdast. The extravasated eiythrocytes are all 

 ingested by megalokaryocytes. ^Migrating leucoc^'tes in large numbers 

 ai^e also absorlicd by tlie large pliagocytic cells. 



' Schmidt, " SauerstotthJiiiKjglobin in Fotuslierzblut," (Jeiit. f. <L nied. Wiss., 

 1H74, No. ,xlvi. 



• Hofliaur, (Jrimdziiye eim'r liiiildijir di-r Menxclilifln'/i I'ljiienta, Leipzig, 1905. 



