A remex feather that is connected to the humerus. [ http://en.wikipedia.org/wiki/Flight_feather#Tertials ]
Synonyms: tertiary flight feather tertial flight feather tertial remex true tertial tertiary remex tertiary remiges tertial remiges
Term information
tertials are connected to the humerus in some species. These elongated "true" tertials act as a protective cover for all or part of the folded primaries and secondaries, and do not qualify as flight feathers as such. However, many authorities use the term tertials to refer to the shorter, more symmetrical innermost secondaries of passerines (which perform the same function as true tertials) in an effort to distinguish them from the other secondaries.