The continuous collection of fluid flowing from both ends of the Fallopian tube of the ewe was attempted by placing a cannula in the ovarian end of the ampulla and a further cannula passing through the wall of the corresponding uterine horn and opposed to the utero-tubal junction. Daily recordings of fluid were made in thirty ewes over a period ranging from 3 to 106 days; observations were also made for oestrous behaviour.
There was an increase in total output of tubal fluid starting on the last day of the oestrous cycle and reaching a maximum about Day 2, after which a gradual decline occurred. A greater part of the total fluid secreted flowed through the ampullar end. Flow through the utero-tubal junction into the uterus remained low for most of the cycle, but markedly increased in all cycles 3·9 ±0·1 days after the onset of oestrus.
The peak flow through the utero-tubal junction would therefore appear to coincide with the time during which ova enter the uterus in the ewe.