PRELIMINARY NOTES TO TABLES. 
(1) Hawks, owls, game birds, and aquatic birds are not in- 
cluded. 
(2) No species have been included that have not been seen 
in Andover by the compiler ; consequently the lists are incomplete. 
Some omissions and inaccuracies may be ascribed to the fact that 
the records are based on less than three years of observation, and 
that this observation has been confined, for the most part, to the 
south-eastern part of the town. 
(3) In the table of Spring Migrants are given birds that 
arrive here in the spring from the south and remain until fall, and 
also birds that pass through here in the spring on the way to 
their northern homes, appearing again in the fall on their way 
southward ; the column headed “‘ Summer Residents ”’ will show at a 
glance to which group each species belongs. Permanent Residents 
are birds that are found here at all seasons. Winter Visitors 
come from the north in the fall and spend the winter, leaving for 
the north in March and April. 
(4) All species — whether summer residents, winter visitors, 
or transients — are most abundant during the migration period. 
This fact is not indicated in the “numbers” column, except in a 
few cases where this disparity is unusually noticeable ; e. g., hermit 
thrush. 
(5) In the migration table, certain dates that, owing to de- 
layed observation, were probably only approximate, are inclosed 
in brackets. ; 
(6) The ’98 and ’g99 records of the “arrivals” frequently 
show a difference of two, or even of three weeks. This is ex- 
plained by the following summary of the weather conditions : 
