Carpenter's principles of human physiology . which are apparently outgrowths from thehypoblast of the diverticulum. These unite and form a network; the meso-blast contained in the meshes becoming at the same time largely convertedinto blood-vessels. In addition to this network of solid hypoblastic cylinders,the diverticula also send out hollow processes lined with hypoblast. On thefourth day the two masses meet beneath the meatus venosus. The blood-vessels of the mesoblast enter into communication with the meatus venosus. It may soon be observed that in those vessels which are connected with t
Carpenter's principles of human physiology . which are apparently outgrowths from thehypoblast of the diverticulum. These unite and form a network; the meso-blast contained in the meshes becoming at the same time largely convertedinto blood-vessels. In addition to this network of solid hypoblastic cylinders,the diverticula also send out hollow processes lined with hypoblast. On thefourth day the two masses meet beneath the meatus venosus. The blood-vessels of the mesoblast enter into communication with the meatus venosus. It may soon be observed that in those vessels which are connected with theposterior part of the liver, the stream of blood is directed from the meatusvenosus into the network of the liver, and they are therefore known as thevenae advehentes. In those connected with the anterior part—the venaerevehentes—the reverse is the case; here the blood flows from the liver intothe meatus venosus. The thick network of solid cylinders represents thehepatic parenchyma of the adult liver, while the hollow processes of the. Origin of the Liver from the intestinal wall in theembryo of the Fowl, on the fourth day of incubation:—a, heart; b, intestine ; c, everted portion givingorigin to liver ; d, liver ; e3 portion of vitelline vesicle. DEVELOPMENT OF THE LIVER AND LUNGS. 933 diverticula are the rudiments of the biliary ducts.* As this is going on, thehepatic mass is gradually removed to a distance from the wall of thealimentary canal; and the caecum is narrowed and lengthened, so as tobecome a mere connecting pedicle, forming, in fact, the main trunk of thehepatic duct.—In the Human embryo, the formation of the Liver begins atabout the third week of intra-uterine existence; the organ is from the firstof very large size, when compared with that of the body; and between thethird and fifth weeks it is one-half the weight of the entire embryo. It is atthat period divided into several lobes. By the third lunar month the liverextends nearly to the pelvis, and al
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectphysiology, bookyear1
