Individual Exercises for the Spring Term 
Five studies follow, which, like those for the Fall Term 
(pages 126 ef seq.), are intended to be made by the student 
working alone. The first three may be entered upon early 
in the term (in our latitude); the other two are for the 
latter half of the term. 
Optional Study 6. A Calendar of Bird Return 
This study is available only to those who know the birds 
at sight, or who are willing to take the necessary trouble 
outside of this course to really make their acquaintance. 
Doubtful identifications will render the record quite worth- 
less. Permission to offer this record will therefore have to 
be obtained in advance of undertaking the work. 
The object of this study is to give opportunity for extend- 
ing personal acquaintance with our local migratory birds 
on the part of students who already know them by sight. 
Field observations, made at least once a week, may con- 
veniently be entered in a cross-ruled table having the left- 
hand column reserved for bird names, and each of the other 
columns devoted to one day’s observations, the date, time of 
day, and relevant weather conditions being written at the 
top. Following each bird’s name, there should be written 
in the proper date columns, the observations made upon it: 
number and sex seen at first appearance; arrival of sexes, 
and of young birds, separately; arrival of ‘waves’ of 
migrants; etc. 
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