The Correlation Between the Eyelids Characteristics and Their Kinetic Performance in Two Wild Birds.

The present avian anatomists have shown a renewed interest in looking at whether the structure of the avian eyelid is accommodated by the kinetic achievement for each eyelid. The current work utilised both histological and anatomical methods to explore the eyelid's structural association with their kinetic, utilising the hoopoe and cattle egret as natural models. The third lid moved only without implicating other lids.

Morphological and functional relationship between the orbital gland and olfaction in Upupa epops (hoopoe) and Bubulcus ibis (cattle egret).

This study used both anatomical and histological techniques to investigate the orbital gland's topographic relationship with the surrounding system, using the hoopoe and cattle egret as biological models. Hoopoe has a spindle-shaped lacrimal gland that is suspended on the lateral edge of the frontal bone, whereas cattle egret has a tiny lacrimal gland that is embedded posteriorly within the periorbital fascia. The hoopoe's lacrimal gland has a single duct that runs parallel to the nasolacrimal duct and opens into the posterior nostril hole.