INDIVIDUAL EXERCISES FOR SUMMER TERM = 323 
Optional Study 13. A Calendar of Bird-nesting 
Nothing is more delightful to observe than the skill with 
which birds hide and build their nests. A few, like those of 
the Baltimore oriole, are hung out in plain view, but most of 
them are so well hidden that we can find them only by most 
careful and unobtrusive watching of the coming and going 
of the parent birds. 
This is a study for those who know how to find the nests, 
and who know how to observe them without causing the 
parent birds to desert them. It would better be under- 
taken by those who have had some experience, for finding 
the nests will require too much time on the part of a beginner. 
For record, the observations on bird-nesting may be writ- 
ten in the columns of a cross-ruled table, in which the first 
column is reserved for bird names, and the other columns 
are reserved each for the observations of one period, with the 
date written at the top. After the name of each bird there 
should be written, under proper date, a brief record of the 
building operations in which the species is engaged. as 
searching for sites, laying foundations, building walls, inter- 
weaving moss or feathers, completing lining, etc. Also 
subsequent nesting phenomena, such as: first egg, last 
egg, hatching, feeding, leaving nest, etc. Ample footnotes 
may contain data for which there is not room in the table. 
Another form of calendar, that may oftentimes be pre- 
ferable where one species of bird, favorable for observation, 
is abundant, may be made up of the observations on pairs 
of birds of a single species; the left-hand column of the table 
for record will then be reserved for the location of the several 
nests. 
