RESPIRA TION OF THE FOE TUS. 7 3 1 
(oxygen) and carry it to the foetus ; at the same time, he recognises that the 
fatus obtains its supply of nutrition in a similar manner. This view of the 
foetal respiration was adopted and extended by Hulse, 1 and by Kay,- who 
states his view in the following words:— "The maternal blood which flows to 
the cotyledons, and encircles the papillae, communicates by them to the blood 
of the foetus the air wherewith itself is impregnate ; as the water flowing 
about the carneous radii of the fish's gills doth the air that is lodged therein to 
them." Mayow's brilliant work was allowed to drop into obscurity, and the 
respiration of the foetus was not understood again until the beginning of this 
century. 
Some physiologists, and among them Leclarc 3 and Geoffrey St. Hilaire, 4 
maintained that the liquor amnii served the purpose of respiration by the skin 
of the foetus. Haller, 5 Hunter," Osiander, 7 Autenrieth and Schutz, 8 Emmert, 9 
Job. Midler, 10 and E. H. Weber 11 stated that no difference could be observed 
in the colour of the bl 1 of the umbilical arteries and vein; on the other 
hand, Seheel, 1 '- Herissant and Diest, 13 Baudelocque, 14 Jcerg, 15 Jeffray, 16 and 
Bostock 17 noticed that the blood going from the placenta to the foetus was 
of a more arterial hue than that going in the opposite direction, although 
there was naturally not so marked a distinction as between the arterial and 
venous blood of the adult. 
Even as late as 1840 the respiration of the foetus was not under- 
stood, for Job.. Miiller, 18 the chief physiologist of the time, held that 
plasma from the mother passed to the foetus, and so supplied the place 
of respiration. Bischoff 19 looked upon the placenta as an organ of the 
mother, and denied the existence of any special respiration ; this view 
was contested by Litzmann, 20 who held that the foetus respired by the 
placenta. Gradually, owing in a great measure to the work of Schwartz, 21 
Gusserow, 22 and Schultze, 23 the truth discovered by Ma vow in 1074 was 
re-established, and received a final proof when Zweifel, 24 following the 
suggestion of Hoppe-Seyler, showed in 1876 that the spectrum of 
oxyhemoglobin could be clearly seen in the umbilical cord before the 
child breathed by its lungs ; that, by taking the precaution to open the 
uterus of a pregnant rabbit in warm normal saline solution, and thus 
1 Quoted from Ray's book, p. 73. 
3 "The Wisdom of God in the Creation," 12th edition, 17f)9, p. 74. 
3 4 5 h t Quoted from Miiller, "Elements of Physiology," Baly's transl., 183S, vol. i. 
pp. 317, 320. 
8 "Experimenta circa calorem fcetus sanguineus ipsius instituta," Tubings, 1799. 
9 Arch. f. d. Physiol., Halle, 1811, Bd. x. S. 122. 
10 "De respiratione fcetus," Lipsiae, 1823, S. 10; "Handbuch der Physiologie," 1840, 
Bd. ii. S. 729. 
11 Hildebrandt's "Anatomie," Bd. iv. S. 524. 
12 " De liquoris amnii asperse arteriae fo-tuum humanorum liatura et usu," Hafnio?, 
1799. 
13 Haller's " Disputationes, " vol. v. pp. 516, 526. 
14 Bichat's "Anatomie generale," tome ii. p. 465. 
15 "Die Zeugung," Leipzig, 1815, S. 273. 
1U "De Placenta." 
17 "Physiology," London, 1828, 2nd edition, vol. ii. p. 199. 
18 "Handbuch der Physiologie," 1840, Bd. ii. S. 729. His words are :— "Die von den 
Blutgefassen angezogenen Safte dringen sodann direct ins Blut des Fbtus. Durch diese Art 
von Wechselwirkung mit mutterlichen Siiften ist bei dem Fcetus auch das Athmen ersetzt 
oder ein ^Equivalent dafiir gegeben." 
19 " Entwiekelungsgeschichte der Saugetltiere und des Menschen," 1842, S. 541. 
20 "Leber die Schwaugerschaft," Wagner's "Handwbrterbuch." 
21 "Die vorzeitigen Athembewegungen," Leipzig, 1858. 
22 Arch. /. Gynaek., Berlin, Bd. iii. 
23 Jenaische Ztschr.f. Med. u. Katuric. Leipzig, Bd. iv. 
24 Arch./. Gynaek.] Berlin, 1876, Bd. ix. S. 291. 
