Perhaps the entire absence of the oil-gland in fantail pigeons may be connected with the great development of their tails.
Sever the backbone at the joint, and then you have all the root of the tail, together with the oil-gland, dissected from the body.
The oil-gland varies in development, and is sometimes quite aborted.
In two tailless fowls which I examined the oil-gland was aborted.
Nitzsch, on the absence of the oil-gland in certain Columb, i. 147.
Tail expanded, directed upwards, formed of many feathers; oil-gland aborted; body and beak rather short.
oil gland n.
A gland, such as a sebaceous gland, that secretes an oily substance.