654 ABSORPTION. 



the venous system, as well as the large size of the liver in the foetus, 

 although not effecting any biliary secretion, and the fact of its receiv- 

 ing immediately the nutritive fluid from the placenta were accounted 

 for. The idea of the agency of the mesenteric veins is now nearly 

 exploded, but not altogether so. There are yet physiologists, and of 

 no little eminence, who esteem them participators in the functions of 

 chylosis with the chyliferous vessels themselves. 



Some of the arguments, based on fallacious data, used by these gen- 

 tlemen, are: First. The mesenteric veins form as much an integrant 

 part of the villi of the intestine as the chyliferous vessels; and they 

 have also, free orifices [?] in the cavity of the intestine. Lieberkiihn,, 1 

 by throwing an injection into the vena portae, observed the fluid ooze 

 out of the villi of the intestine; and M. Ribes 2 obtained the same result 

 by injecting spirit of turpentine coloured black. These experiments 

 it need hardly be said are insufficient to establish the fact of open 

 mouths. Situate, as those vessels are, in an extremely loose tissue, 

 which affords them but little support, the slightest injecting force might 

 be expected to rupture them. Secondly. Chyle has often been found 

 in the mesenteric veins. Swammerdam asserts, that, having placed a 

 ligature around these veins in a living animal, whilst digestion was 

 going on, he saw whitish, chylous striae in their blood ; and Tiedemann 

 and Gmelin affirm, that they have often, in their experiments, observed 

 the same appearance. If the fact of the identity of these striae with 

 chyle were well established, we should have to bend to the weight of 

 evidence. This is not, however, the case. No other reason for the 

 belief is afforded than their colour. The arguments against the me- 

 senteric veins having the power of forming chyle we think irresistible. 

 A distinct apparatus exists, which scarcely ever contains any thing 

 but chyle; and consequently, it would seem unnecessary, that the 

 mesenteric veins should participate in the function, especially as the 

 fluid which circulates in them is most heterogeneous ; and, as we shall 

 see, a compound of various adventitious and other absorptions. Grant- 

 ing, however, that these striae are true ehyle, it would by no means fol- 

 low absolutely, that it should be formed by the mesenteric veins. A com- 

 munication may exist between the chyliferous vessels and these veins. 

 Wallaeus 3 asserts, that having placed a ligature on the lymphatic trunks 

 of the intestine, chyle passed into the vena portae. Rosen, Meckel, 4 

 and Lobstein affirm, that by the use of injections they detected this 

 inosculation. Lippi 5 states, that the chyliferous vessels have numerous 

 anastomoses with the veins, not only in their course along the mesentery 

 before they enter the mesenteric glands, but also in the glands them- 

 selves. Tiedemann and Gmelin concur in the existence of this last 

 anastomosis, and MM. Leuret and Lassaigne found that a ligature ap- 

 plied round the vena portae occasioned the reflux of blood into the tho- 



1 Dissert, de Fabric. Villor. Intestin., Lugd. Bat, 1745. 



2 Memoir, de la Societe Medicale d'Emulation, viii. 621. 



a Medica Omnia, &c., ad Chyli et Sanguinis Circul., Lond., 1660. 



4 Diss. Epist. ad Haller. de Vasis Lymph., &c., Berol., 1757 ; Nov. Exper. de Finibus Ve- 

 namm et Vaa. Lymph., Berol., 1772 ; and Manuel d'Anatomie, &c., French edit., by Jourdan, 

 i. 179. 



5 Illustrazioni Fisiologiche e Patologiche del Sistema Linfatico-Chilifero, Firenze, 1825. 



