PHYSICAL PROPERTIES OF THE ALLANTOIC AND AMNIOTIC FLUIDS OF THE CHICK : II. HYDROGEN ION CONCENTRATION.

1. The hydrogen ion concentration of the allantoic and amniotic fluids of the developing chick has been determined over the period of incubation between the 7th and 19th days using the glass electrode technique. 2. Changes in this property have been related to changes in the chemical composition of these two fluids. 3. The results of this investigation have been compared with those obtained by other workers. Excellent confirmation has been afforded the work of Yamada, whereas the work of Aggazzotti, which has long been accepted, is shown to be in error.