16 INTRODUCTION. 



ber that eggs often vary greatly in value in different parts of 

 the country, and do not accept any price-list as a basis for ex- 

 chano*e. Endeavor by energy to arrive at approximate com- 

 pletion, have some definite object in view, such as a cabinet 

 comprising all the eggs of Massachusetts, and do not unwisely 

 form a miscellaneous collection everywhere incomplete. 



S. To know the notes of all our birds is a great help in 

 finding their nests, and in finding, distinguishing, or studying 

 the birds themselves, who sing chiefly on or soon after their 

 arrival from the South, during their migrations, and the mat- 

 ing-season in spring or early summer. It is best to study 

 their music at sunrise or in the early morning (particularly 

 in the case of species migrating), and also at evening. Even 

 families may (to a limited extent) be classified by their notes. 

 To study birds in relation to their habits or notes walk in 

 their haunts, continually pausing to catch the slightest sound, 

 which, if not recognized, should be traced to its source, and 

 waiting to allow the birds to gather about or approach you. 

 If necessary, follow them silently and persistently ; but re- 

 member that stealthiness sometimes alarms them more than 

 an open approach.* If several species be together, do not be 

 misled by the confusion of their songs, and do not hastily 

 attribute the note of one kind to another bird immediately 

 near. Both squirrels and " chipmonks " frequently produce 

 notes which might excusably distract the attention of an un- 

 practiced ornithologist. By looking up, especially on very 

 clear days, you may often see Hawks, or other birds, flying 

 over silently. 



An opera-glass, if a sufficiently strong magnifier, or occasion- 

 ally a telescope, will be found very useful, as it enables one 

 to recognize a bird without disturbing it, and to distinguish 

 colors, when the object is distant, or at a great height among 



* Birds which haunt thickets, reeds, " screeping " sound. This excites their 



or the tops of tall trees may be fre- sympathy or curiosity, or both, and 



quently lured from concealment or will frequently draw about the per- 



brought down near the ground by pla- former nearly all the small birds which 



cing the lips against the back of the inhabit the neighborhood. W. B. 

 hand and making a continuous, shrill 



