THE BODY. 
5 
The web is closely attached to the upper edge of the 
horny convex surface of the flexible shaft, and occupies 
from a fourth to a fifth part of its side. Their filaments 
are threadlike in form and almost cylindrical; in the 
quill-feathers, however, the laminae are trapezoidal in 
transverse section, more deep than broad, and wider at 
the top than below. These are placed at an angle of 
about forty degrees to the shaft, inclining lengthways 
towards its extremity, with their flat sides next each 
other. The webs of the latter are in turn composed 
of two fringes of filaments, and are attached to their 
shafts in the same way as the former to the principal 
shaft; still each of those laminae, turning towards the 
body of the bird, is invariably covered by the outer web 
of the next ray. 
By means of the hair-like processes, which are attached 
to the above filaments, being hooked and cohering toge¬ 
ther, the most intimate union of each part of the filament 
is effected; so skilfully are they contrived and so closely 
do they cohere together as to be impermeable to wet and 
impenetrable by the air. It requires, indeed, some degree 
of force to break up the uniformly compact arrangement 
of their component parts. The laminas or filaments of 
the other feathers, as well as all down, hang more 
loosely, and are placed further apart; thus they are 
lighter and more elastic. In this case the cilia do not 
cohere; their function being simply to sustain the 
warmth generated in the body, such cohesion is not 
needed. 
Individual feathers exhibit great differences in form, 
though always in harmony with their colouring. A green 
feather is differently constructed from a red one, and the 
formation of a red feather differs from that of a black or 
