BIRDS OF THE UNITED STATES. 
29 
nests in their ordinary positions upon small bushes, or in bunches of swamp 
grass, but few, we opine, have met with them elsewhere. Mr. Maynard, 
as stated by Dr. Brewer, seems to have been the first to notice this change. 
While exploring an island in the marshes of Essex River, he found a 
number of nests in trees at an elevation of twenty feet from the ground. 
One of these structures, which was purse-shaped, was composed entirely of 
eel grass, and placed u]Don a sapling, at a height of fourteen feet. 
High grounds are seldom chosen for nidificating ]:)urposes, for the 
obvious reason that they offer 2>oor facilities for food-collection ; the aquatic 
larvae, may-flies, dragon-flies, and mosquitoes, which constitute a conspic- 
uous part of the diet of these birds, being only found in marshy situations. 
Even here a preference is manifested for certain positions. Small bushes 
along the borders of streams, from the two-fold advantages which they 
jjossess, are almost wholly adopted in some localities. Being convenient to 
a^^propriate food-stuffs, they are placed beyond the reach of snakes, partic- 
ularly water snakes, which have a decided partiality for young birds. 
Having selected a building-spot, the pair proceed with all possible 
disj)atch to construct a home. This requires the joint labor of the sexes, 
during the early mornings and evenings, for a period of about five days. 
The articles of composition are chiefly collected by the male, while the 
female performs the more difficult oj)eration of jDutting them in ] 50 sition. 
Considerable differences are often noticeable in these structures. Those 
placed upon bushes are, as a general thing, more symmetrical and compact 
than those found in clumps of grasses, and differ still further in being- 
plastered with mud on the outside, which adds to their durability ; while, 
on the other hand, nests enclosed by tall overarching grasses, have a loose- 
ness of arrangement that will scarcely bear manipulation. But where the 
nest is placed in fields of timothy and clover, there is evidence of great 
pains having been taken in its construction. 
Having finished their domicile, generally on the following day, but 
sometimes not for nearly a week afterwards, as is the case when mud and 
other damp substances have been used in building, the female begins to 
