OF THE HUMAN UMBILICAL CORD AND PLACENTA. 351 



foetal end of the cord, pass there onwards, according to the dissections and injec- 

 tions of ScHOTT and Van dee, Kolk, for two or three lines, but they do not stretch 

 for any further distance along the track of the cord itself. They exist, in other 

 words, in the short persistent end of the cord, which remains attached after birth 

 to the umbilicus, and which ultimately fills up the umbilical ring, but they are 

 not found in that great mass which forms the deciduous part of the cord, running 

 from the child to the placenta. 



The same observation holds true, according to Schott and Valentin, regarding 

 the short extension of the terminal twigs of the nerves of the foetus, which pass 

 out of the body of the foetus along with the umbilical vessels through the umbilical 

 ring. Apparently, like the capillaries, they do not pass further than one or two 

 lines beyond that ring. Numerous attempts have been made to trace nerves in 

 the course of the umbilical cord, but no continuous line of nerve tissue has been 

 detected in its track. In former times, Chaussier and Baer fancied that they had 

 found nervous fibres running along it. Anatomists generally hold that these 

 supposed nerves were only the deceptive remains of the obliterated vitelline duct 

 or omphalo-mesenteric vessels. At all events, since the microscope has come to 

 add its great and necessary aid to this inquiry, the search has been diligently 

 renewed, but hitherto in vain. No nervous fibril, or continuation of fibrils, has 

 been detected by it in this structure. 



Several years ago, my nephew, Dr Alexander Simpson, when writing his 

 Thesis on the Umbilical Cord, set himself assiduously, with the scalpel and 

 microscope, to the investigation of this question of the presence or absence of 

 nerves in the cord. These investigations were kindly overlooked by Professor 

 GooDsiR. The result was, that not a trace of a nervous fibril could be detected 

 in this structure. 



In some observations which I published twelve years ago, on the Contractility 

 of the Umbilical Vessels, I attempted to show that we could generally, after the 

 child is born, produce in the umbilical arteries and veins, by the local appli- 

 cation of mechanical, chemical, or electrical stimulants, local contractions, which 

 did not again relax. But this form of contractility does not prove, I believe, 

 that nervous fibres exist in the walls of the umbilical arteries and veins ; for 

 such local phenomena of contractility occur in the lower animals, where no 

 nerve fibres have been found to exist, as in the Actinia, Medusa, &c. Let me 

 add, that one great exceptional peculiarit}^ in the low type of structure of the 

 umbilical cord is the presence of strong and well-marked contractile muscular 

 fibres in the walls of its vessels, though these fibres are totally unprovided with 

 nerves. 



Lymphatics have been alleged to exist in the cord by various authors, as 

 Wrisberg, Schrceger, and Michaelis, and especially by Fohman. The umbilical 

 lymphatics were supposed by Fohman to be capable of being injected by quick- 



