INTRODUCTION. 
13 
are not very dissimilar to these ; yet it is singular to remark, that 
while our common geese and ducks, like domestic fowls, have no 
permanent selective attachment for their mates, the Canadian Wild- 
goose, the Eider-duck, and some others, are constantly and faithfully 
paired through the season ; so that this neglect of comfortable ac- 
commodation for the young in the fabrication of an artificial nest, 
common to these with the rest of their tribe, has less connexion 
with the requisition of mutual aid, than with the hardy and pre- 
cocious habits of these unmusical, coarse, and retiring birds. It is 
true, that some of them show considerable address, if little of art, 
in providing security for their brood ; in this • way some of the 
Razor-bills (including the Common Puffin) do not trust the exposure 
of their eggs, like the Gulls, who rather rely on the solitude of their 
retreat, than art in its defence ; but with considerable labor some 
of the Alcas form a deep burrow for the security of their eggs and 
young. 
Birds of the same genus differ much in their modes of nidification. 
Thus the Martin makes a nest within a rough-cast rampart of mud, 
and enters by a flat opening in the upper edge. The Cliff Swallow 
of Bonaparte, seen about Portland in Maine and Nova Scotia, as 
well as in the remote regions of the West, conceals its warm and 
feathered nest in a receptacle of agglutinated mud, resembling a 
narrow-necked purse or retort. Another species, in the Indian seas, 
forms a small receptacle for its young entirely of interlaced gelatin- 
ous fibres, provided by the mouth and stomach; these fabrics, stuck 
in clusters against the rocks, are collected by the Chinese, and boiled 
and eaten in soups as the rarest delicacy. The Bank-Martin, like 
the King-Fisher, burrows deep into the friable banks of rivers to 
secure a depository for its scantily feathered nest. The Chimney- 
Swallow, originally an inhabitant of hollow trees, builds in empty 
chimneys a mere nest of agglutinated twigs. The Woodpecker, 
Nuthatch, Titmouse, and our rural Blue-Bird, secure their young 
in hollow trees ; and the first often gouge and dig through the 
solid wood with the success and industry of instinctive carpenters, 
and without the aid of any other chisel than their wedged bills. 
But the most consummate ingenuity of ornithal architecture is 
displayed by the smaller and more social tribes of birds, who, in 
proportion to their natural enemies, foreseen by nature, are provided 
with the means of instinctive defence. In this labor both sexes 
generally unite, and are sometimes occupied a week or more in 
completing this temporary habitation for their young. We can only 
2 
