3. There are cases of birth 3. This means that the fetus 

 of fetuses devoid of is nourished not only on 

 mouth or missing a head. the amniotic fluid. 



4. If the fetus was fed by 4. Amniotic fluid is light 

 swallowing amniotic food, from which only very 

 fluid, then his intes- little fecal matter remains 

 tines should have been 



filled with feces. 



As to arguments in favor of nutrition by the amniotic 

 fluid, Pavlov reported the evidence of investigators who had 

 found amniotic fluid and also hairs of the embryonic fur in 

 the fetal stomach, confirmed by chemical analysis. Favoring 

 the intake of amniotic fluid by the skin are, in Pavlov's 

 opinion, observations about the filling with fluid of the 

 distended subcutaneous lymphatic vessels of the fetus. After 

 giving these data, he moved to the following cautious 

 conclusion: "It must not, however, be thought that the fetus 

 feeds exclusively on amniotic fluid, because it is impossible 

 to neglect the nutritional value of the milky serum" (§ 84) . 



After reviewing different opinions about the sources of 

 fetal nutrition, Pavlov moved to the considerations which make 

 up the third chapter of his dissertation. First of all, 

 setting aside the possible accusation of presumption and vanity, 

 he defended his right to "dispute the opinions of scientists and 

 to build his own path, leading to the truth." In his justifica- 

 tion he said: "I am seeking the truth and, for this reason, I 

 do not want to swear by the words of the teachers" (§ 87). 



For solving the question raised, Pavlov chose the path 

 of comparative investigation. He noted that different living 

 creatures are characterized by different degrees of development, 

 man and infusoria forming the extremes between which there is 

 gradual transition. The different degrees of perfection of 

 organization correspond to the complexity of organization: 

 the simpler the organization, the less it is improved, and the 

 reverse. The organization of the human is the most complicated, 

 hence it is considered the most improved of all animals. So 

 for the explanation of the function of any organism, the more 

 difficult it is, the more complex it is. And "the physiology 



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