GLOSSARY OF TERMS *IX 



Htjmerus. — The bone of the upper arm, i.e. the most proximally situated 



bone of the wing. 

 Hyoid. — The cartilaginous and bony framework of the tongue. 



Iris. — The, often distinctively, coloured portion of the eye, in the form of a 

 circular curtain, having a central circular aperture, which is called 

 " the pupil." (See fig., p. *xvi.) 



Juvenile bird. — As here used refers to a bird in its first covering of true 

 feathers, which usually immediately succeeds the down of the nestling. 



Knee. — The forwardly directed joint in the upper part of the bird's leg, 

 always hidden by feathers. The more evident, distal and backwardly- 

 directed jomt is often erroneously called the bird's knee, but is in 

 reality the ankle. 



Lamella. — Small plates or scales. 



Lamellated. — Covered with lamellae (small plates or scales). 



Lamellirostres. — Cuvier's name in 1817 for the Anatidse. 



Lamina. — A small thin plate. 



Lanceolate. — Lance-shaped, e.g. a feather or a bird's tail is said to be 

 lanceolate when the two sides are evenly graduated to a point ; the 

 long axis being greatly in excess of the transverse (c/. Cttneate). 



Lobes. — Fibrous, skin-covered outgrowths such as those of the toes of the 

 Coot. 



Malar. — Of or belonging to the cheek. In birds used to denote the region 

 extending down the side of the throat from the base of the lower jaw. 

 (See fig., p. *xvl) 



Mandible. — The jaw — generally used with the qualifymg adjectives upper 

 or lower, including the horny sheath as well as the bone. 



Melanism. — ^The abnormal presence of black or very dark-coloured 



plumage. 

 Nail. — ^The term applied to the inverted shield-shaped horny plate at the 



tip of the upper mandible in the Ducks, Geese and Swans. 



Nares. — ^The cavities of the nose; anterior nares=:the outside openings of 

 the nostrils : posterior nares = the openings of the nose into the 

 throat. In ornithology the word nares alone is often loosely applied 

 to the external apertures. 



Nearctic region. — One of the six great Zoo -geographical regions of the 

 world, comprising North America and reaching into Mexico (c/. Pal^e- 

 ARCTic Region). 



Neossoptiles. — A term applied to the down-feathers which first clothe the 

 newly-hatched bird. They are characterized by the calamus being 

 very short, the rhachis ill defined or absent, the rami long and slender, 

 the cilia usually absent and the aftershaft always so in British species. 

 In some species the neossoptiles are either nearly or entirely suppressed. 



Nestling. — Here used to refer to a bird from the time it is hatched until 

 the growth of the Teleoptiles [q.v.). 



Nuchal. — Of or belonging to the nape. The region of the junction of the neck 

 with the back of the head. 



Oil glands. — The only glands of the skin in birds, consisting of two some- 

 what heart-shaped bodies lying side by side just above the root of 

 the tail and opening backwards on to the surface by several orifices 

 frequently prolonged into a projecting nipple which in some famihes 

 is surrounded by a circle of down and stiff feathers. Best developed 

 in the water birds. 



Operculum. — A cover or lid : applied to the fleshy flap covering the nostrils 

 and external aperture of the ears in some birds. 



