Infundibulum, Latin for funnel.

The uterine tubes and the hypothalamus both have infundibula which, like funnels, are hollow and tapered. The infundibulum of the uterine tube funnels the ovulated ovum deeper into the tube's lumen.

A Roman infundibulum (funnel). Based on a woodcut of a glass infundibulum found in the ruins at Pompeii.
Modified from the Dictionary of Greek and Roman Antiquities, 3rd Edition by Anthony Rich. 1874

The hypothalamic infundibulum connects with the pituitary, serving as a stalk that attaches the pituitary to the hypothalamus, both anatomically and physiologically. Its hollow center is a continuation of the third ventricle. Calling this structure the infundibulum made eminent sense to the early anatomists, not just because of form but also for perceived function: it was thought for more than a millennium that mucus from the brain's ventricles was funneled through the infundibulum into the pituitary (which, it was believed, then secreted the mucus into the nasopharynx).

Other structures with infundibula include the ethmoid bone and gall bladder.

The pituitary (A) and infundibulum (B): an inaccurate representation. From De Humani Corporis Fabrica, 1543, by Andreas Vesalius.

The funnel shape of the infundibulum is much exaggerated and the pituitary is treated almost as an afterthought. Also shown are four ducts (C-F) through which the pituitary supposedly secreted mucus. These ducts in actual fact don't exist.

This is a excellent
example of how preconceived notions (i.e. the secretory function of the pituitary as discussed above) can influence observations, even when the observer is one of the greatest of all anatomists.


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