Abstract
The association of hepatic endoderm of 9- to 28-somite mouse embryos with chick hepatic or pulmonary mesenchymes resulted in the differentiation of a chimaeric liver in which the hepatocytes came from the mouse endoderm while the chick mesenchyme gave rise to the endothelium lining the blood sinusoids. In these chimaeric livers, hepatocytes differentiated normally (glycogen storage and α-foetoprotein (α-FP) production) while the haemopoietec cell line did not develop.