656 PHILOSOPHICAL TRANSACTIONS, [aNNO 1775. 



constituted the umbilical arteries, one of which was considerably larger than the 

 other. And then below these, 2 other branches descend to the inferior extremi- 

 ties. A large umbilical vein came in at the navel, and was immediately divided 

 into 2 considerable branches ; one ascending, the other descending. Each of 

 these was again subdivided into smaller and smaller branches, which, as they 

 passed upwards and downwards, seemed to correspond with the different rami- 

 fications of the ascending and descending aorta. The funis umbilicalis was only 

 about 2 inches in length,* and so very tender also, that it unavoidably separated 

 near the navel of the child during the delivery. Whether therefore there was any 

 pulsation in this short funis, he was not able to determine. The placenta was 

 not particularly examined. 



There were evidently in this foetus 2 distinct systems of vessels, arteries and 

 veins,-}- that carried red blood. ;}: It was plain also, that the blood passed from 

 the internal iliac arteries, through the hypogastrics and umbilicals to the pla- 

 centa, and was returned from it by the umbilical vein to the navel, and thence 

 distributed in the maimer before observed. But as there was no heart, nor any 

 thing analogous to one, it became extremely difficult to ascertain the powers by 

 which the circulation was carried on through this physiological phenomenon. 

 Might we not however venture to advance a conjecture, that the peristaltic, or 

 living muscular power of the arteries, was principally subservient to this im- 

 portant end? Many examples are to be met with in the collections of the cu- 

 rious and learned in the different parts of Europe,§ which are somewhat similar 

 to that now related. When carefully examined however, excepting a very few 

 instances, they are generally found either essentially to differ, or else their struc- 

 ture has not been, with any tolerable precision, explained. The present history 



• An exactly similar circumstance to this Dr. C. took particular notice of, in tlie delivery of another 

 almost brainless monster.— Orig. 



f Mr. Hewson attempted to inject the whole blood vessels by the umbilical vein as usual. To his 

 great surprize, no part of the injection returned by the umbilical arteries. He could not account for 

 this singularity at that time : but as only a part of the vessels were filled, he injected afresh by one of 

 the hypogastric arteries. On dissection afterwards, this mystery was unravelled by the heart's being 

 totally absent. It tlien appeared also, that by the first injection he had tiUed the venal system, and 

 by the latter the arterial. — Orig. 



J See a very curious case related by Mens. Winslow, in the Memoires de L' Academic des Sciences 

 for 1740, p. 586 and 604. Among other remarkable singularities in this little moastrous abortion of 

 6 months, that excellent anatomist particiJarly takes notice, that there was no appearance of one 

 drop of red blood in any of its vessels, which were universally filled with a serous lymph ; and that 

 there were no vestiges of any veins at all. — Orig. 



§ F. Licetus, de Monstris, p. 300 et seq. Palfyn, Traite des Monstres, p. 325. Cheselden's 

 Anatomy, 5th ed. p. 379. Phil. Trans., 1739-40, N° 456. Ibid. 1767, p. 1. L'Academie des 

 Sciences, Hist. 1720, p. 13. Ibid. Mem. 17'-'0, p. 8. Ibid. 1740, p. 586 and p. 592. Miscellania 

 Curiosa Ephemeridum Germanicarum Ann. 1 y, p. 258. Acta Eruditorum Lipsiae, Ann. 1724, p. 

 501.— Orig. 



