FASTIDIOUS NESTING HABITS OF A FEW BIRDS. 113 
ers, basket makers, etc. These things are very appar- 
ent when the nest is at hand, and the styles may be 
combined as in the robin’s nest. 
The swifts might be styled cementers, since their 
nests largely consists of twigs glued together by a 
sticky saliva, secreted especially during the nesting 
season. Of course it is well known that one Chinese 
swift omits the twigs altogether. 
It is probable that many birds which build such 
neat, compact nests, also use saliva in felting, espe- 
cially the hummingbirds, which are next of kin to the 
swifts. It is well known that the woodpecker uses 
no nest material at all except the fine chips of the 
digging, feeling perhaps that if he finishes his home 
in hardwood his young can do without the upholster- 
ing. Here is a striking illustration that the habits of 
the young and the style of the nest are related, since 
little woodpeckers after a few days do not sit upon 
the bottom, but cling constantly to the sides of the 
cavity. There is little need of a mattress. 
It would be interesting, of course, to note the 
many striking or unusual locations of nests and their 
peculiarities of material, use and structure; but it 
would take a volume, and reference must be had to 
special works on the subject. 
Something of the relations of nest and egg colors 
will be noted in the next chapter. 
It is likely that no birds use the same nest to 
rear a subsequent brood in the same season, but they 
nearly always build the second nest in the same region. 
But many birds that build in holes use the same hole, 
