NOTES 



263 



fermonibus] The work Historia Na= 

 tvralis Brasiliae . . . Lvgdvn. Batavorvm 

 et Amstelodami 1 648 contains Guilielmi 

 Pisonis . . . De Medicina Brasiliensi Li* 

 bri Qvatvor and GeorgI Margravl . . . 

 Historic Rervm Natvvalivm Brasiliae, 

 Libri Octo. — See note to vol. I p. 118. 

 1. 17 from top. 



P. 207. 1. 9 from top. 



Bartholinus] Th. Bartholin while 

 a professor at the University of Copen* 

 hagen often left town for long periods 

 at a time and went to live at his estate 

 Hagestedgaard. 



XVII 



DE VITELLI IN INTESTINA 

 PULLI TRANSITU EPISTOLA. 



The observation, on which this Trea* 

 tise is based, must have been made after 

 Steno's return to Copenhagen in the 

 spring of 1664, and before the 12th of 

 June (old style), the date of the Treatise. 

 It was published together with the two 

 previous Treatises (XV and XVI) in 

 Nicolai Stenonis De Musculis &■ Glan= 

 dulis obfervationum fpecimen . . . Haf* 

 niae 1664. It is dedicated to PaulusBar* 

 bette, a celebrated Amsterdam surgeon 

 and author of medical books. See JBiogr. 

 U^oorc/enboeA: der Nederlanden. vol. II 

 1. p. 107. 



In this Treatise Steno mentions his 

 discovery of the vitelline duct in the 

 newly hatched chicken. Observe, how* 

 ever, that this formation in the fetus of 

 the hen was known and described as 

 early as by Aristotle l ), who also knew 

 that the function of the vitelline duct 

 was that of conducting the yolk into 



') De Animalibus Historia. VI 3. 

 De Generatione Animalium. Ill 2. 



the intestines of the fetus, with the view 

 of nourishing the latter. But Aristotle 

 entirely misunderstood the manner in 

 which the vitelline duct originates; he 

 thought that is was a transformation of 

 one of the two Jiopoi cp\e|3ixoi that pro* 

 ceed from the heart at an early stage of 

 the fetal life. The knowledge of the vitel* 

 line duct was preserved throughout the 

 antiquity, until as late as the 16th century, 

 its formation and function being very 

 clearly described in 1573 by Volcherus 

 Coiterus 1 ). But after that, strange to say, 

 the knowledge of the vitelline duct was 

 lost, and though of course prominent 

 investigators like Fabricius ab Aqvapen= 

 dente,-) Spigelius*) and Harvey*) tho» 

 roughly knew the works of their pre* 

 decessors, from Aristotle to Coiter, 

 they did not understand that Aristotle 

 and all his successors described a pas* 

 sage from the yolk*sac to the intestines, 

 through which passage the yolk was 

 conducted to the intestines with the view 

 of nourishing the fetus. In their own 

 investigations they never themselves 

 came across the vitelline duct, and ac* 

 cording to Harvey the nourishment of 

 the fetus took place in a twofold man* 

 ner, partly by the fetus swallowing the 

 amniotic fluid, partly by its receiving 

 the purior et sincerior pars of the latter 

 direct into the vascular system through 

 the umbilical veins. 



') Extemawm Et Internarvm Principalivm Hv- 

 mani Corporis Partivm Tabvbe . . . Avtore Vol' 

 chew Coiter . . . Noribergae 1573. pp. 35-36. 



2 ) Hieronymi Fabricii Ab Aqvapendente De 

 Formato Foetv. Venetiis 1600. 



Hieronymi Fabricii Ab Aqvapendente . . . De 

 Formatione Ovi. Et Pvlli Tractatvs Accvratis. 

 simvs . . . Patavii 1621. 



") Adriani Spigelii . . . De Formato Fotv Liber 

 Singvlaris . . . Patauij 1626. 



*) Exercitationes De Generatione Animalium 

 . . . Autore Gvilielmo Harveo. Londini 1651. 



