10 INTRODUCTION. 



6. The primaries, or principal quills. These form the ter- 

 mination of the wing, and are the strongest feathers on the 

 bird. They rise from the hand, or that portion of the wing 

 which is below the wrist joint, and which, though it some- 

 times contains three distinct bones in its length, is frequently 

 called the first (or third) bone of the wing. These feathers 

 are numbered in order ; the outer one, or that which is fore- 

 most in the expanded or lowest in the closed wing, is the first. 

 Considerable differences in the form of wings arise from the 

 various lengths of the feathers ; and these are accompanied 

 by corresponding variations in the style of flight. If the first 

 or second of these feathers be the longest in the wing (and 

 when the second is longest the first comes underneath and 

 supports it), the bird can turn in the air with greater ease than 

 with any other form of wing. Birds which hawk flying, or 

 catch their prey while on the wing, whether they catch other 

 birds as the falcons, or insects as the swallows, have their 

 wings of this construction. The pigeons, which are also birds 

 of excellent wing, have the second feather longest ; but the 

 lapwing, which is remarkable for the variety of its motions in 

 the air, has the longest feather farther into the wing. 



7. The secondaries, or second quills of the wings. They 

 arise from that part of the wing which is commonly called 

 the second bone, and which answers to the fore arm in man. 

 They arise from it towards the wrist joint, and admit of a 

 folding of the wing between them and the primaries when 

 the wing is closed. When the wing is open, they sometimes 

 appear a continuation of the same curve with the primaries, 

 and at other times they form a distinct curve of their own. 



8. The tertiaries, or third quills of the wings. They arise 

 chiefly from the same bones as the secondaries, but nearer to 

 the elbow joint. In some birds, especially those which are 

 in the habit of running very swiftly with the wings partially 

 opened, the tertiaries are often so long and come so to a point, 



