THE PLACENTA AS AN ENDOCRIN ORGAN 659 



would lead one to suppose the possibility of an increased permeability 

 between fetus and mother. It accordingly appears probable that the cause 

 of eclampsia does not lie in any inherent production of a secretion by the 

 placenta, but rather that this disorder arises from a decrease or perversion, 

 or both, of the intermediary metabolic function of the placenta, accom- 

 panied by an increased permeability of the endcthelium covering the villi 

 projecting into the maternal sinuses; the combined effect of this increased 

 permeability and decreased detoxicating activity is a flooding of the 

 maternal organism with the incompletely hydrolyzed by-products of the 

 fetal metabolism. This would seem to put such extra burden upon the 

 liver and kidneys of the mother that these tissues are unable to meet the 

 demands upon them, with the result that the subsequent characteristic 

 manifestations of an acute toxemia appear. 



The Placenta as a Factor in Growth. A certain number of direct 

 feeding experiments have been carried on during the past few years, the 

 results of which seem to indicate that when placental tissue is fed to 

 young animals an acceleration of growth results. These investigations, 

 however, present no valid evidence that there is present in the placenta a 

 specific growth-promoting substance, inasmuch as the increased growth 

 observed may well have been due to the addition to the diet of either an 

 optimum supply of ammo-acid precursors, or to an increased vitamin 

 content of the diet. The results of Emmett and Luros, however, show that 

 fat-soluble A vitamin is not a general constituent of the ductless glands. 



That certain of the domestic animals commonly consume the after- 

 birth is well known. Van Hoosen was the first to report an increased 

 growth of breast fed infants when subsisting upon milk produced during 

 the maternal ingestion of desiccated placenta. The plan and scope of 

 her work do not permit the drawing of any definite conclusions, but 

 do seem to show the indications of a tendency. In a study of the effect 

 of the ingestion of desiccated placenta on the variations in the chemical 

 composition of human milk during the first eleven days after parturition, 

 Hammett and McNeile observed that the infants feeding upon this milk 

 made a more rapid recovery from the postnatal decline in weight than 

 infants subsisting on milk uninfluenced by the maternal ingestion of the 

 desiccated placenta, and the assumption was made that there is in the 

 placenta a growth promoting substance, which is passed on to the infants 

 in the milk when placental material is fed to the mothers. Cornell, in a 

 study of the galactagogic action of the placenta, pointed to the possibility 

 that the feeding of such material to nursing mothers has some effect 

 on the growth of breast fed infants. He found that 87 per cent of those 

 infants receiving milk from mothers ingesting desiccated placenta regained 

 their birth weight by the fourth or fifth day, whereas but 67 per cent of 

 those ingesting milk from mothers not receiving this material had reached 

 their original weight during the same period. This augmentation of 



