Abstract
Pancreases taken from chick embryos secrete amylase in vitro when stimulated by cholinergic drugs. Rates of secretion increase with developmental age. The pancreas isolated together with the duodenal loop from the 8 day embryo is already capable of secretion in vitro. It is therefore concluded that the pancreas acquires the ability to secrete digestive enzymes more than 10 days before the beginning of the prominent biochemical and morphological changes associated with the maturation of the gland.