5 
little opening on its under surface, where it joins the shaft, by 
which its cavity communicates with the exterior, the tube is 
cylindrical but the shaft rather square on section. On each side 
of the shaft are the barbs, and each barb has another series of 
divisions on each side called barbules. In the chief feather for 
flying, every barbule on the further side of the barb has a little 
hook by which it more securely overlaps the barbules of the next 
barb so as to increase the resistance to the air and make the 
feather more rigid Other peculiarities in birds are the air sacs 
which are developed in different parts of the body and communicate 
with the lungs, and the air centres in many of the bones which 
also communicate with the lungs. Then the use of the two fore 
limbs for flying necessitates many modifications of beak, neck, and 
claws for seizing and holding. The beak undergoes very re- 
markable modifications in different birds, which I hope to be able 
to dwell on, on some future occasion. The neck is usually made 
of many more vertebre than in Mammals, and it is extremely 
flexible, and always long enough for the beak to be able to reach 
the base of the tail. The claws and toes are most serviceable for 
holding, climbing, tearing, and fighting according to the needs of 
the owners. 
I will now proceed to consider some of our common birds of the 
Passerine Order, or Perching Birds. We all know the Thrush, 
Turdus musicus, and a very welcome visitor of our gardens it is to 
most of us. Who has not seen and heard it singing its sweet song 
perched on the same branch of a tree for nearly an hour without. 
moving an inch? I have had a telescope directed at one whilst it 
was singing about 30 yds. away, and it brought it apparently to 
within about 6 or 8 feet, so that the bright eye and rapidly moving 
beak and throat made a very pretty object adding to the beauty of 
the song. It has what I should calla soft but bright liquid eye 
which seems to look in all directions at once. The feeding habits 
of the Thrush are very peculiar. If you are walking in the further 
part of the Warren you may often pass by a heap of broken snail 
shells on the top of a little mound with one or two large stones 
projecting from the ground; these fragments are made by the 
Thrush. It takes the snail shellin its beak and gives it a vigorous 
blow against the stone, repeating the action until the shell is so 
broken that the snail can be extracted. So. that as the Butcher 
Bird has its larder, so the Thrush has its kitchen midden or shell 
mound. Hear what Macgillivray says of the song of the Thrush 
in the Hebrides :—“ In other places the song of the Thrush may 
be lively and cheering ; here in the ocean-girt solitude, it is gentle 
and soothing. By its magic influence it smoothes the ruffled surface 
of the sea of human feelings, as it-floats over it at intervals with its 
varied swells and cadences, like the perfumed wavelets of the 
