FAMILY Cuculldes. 



obscure interval of a third or fourth (as in above record} 

 Again, these tones are at times so distinctly separated 

 that they assume an individual independence, with the 

 intervals no longer obscure : 



RitarJ. 



Cow-oo, Cow-oo, Cou-oo t cou-oo, eou-oo,cffiu-oo, con-coo. 



This is by no means the common song of the Black- 

 bill, but it certainly is not rare. Here is variety again : 



cu.-c.oo-oq, cucucoo-oo. 



the little musician is not content until he shall ring 

 all the possible changes of such vocal limitations ! Mi. 

 Cheney is also an authority for the statement that this 

 bird is quite capable of singing his song in two well- 

 separated tones. He writes: "Early one June morn- 

 ing, ... a bird was exercising his voice in a manner 

 that set me on the alert ; it was the voice of a Cuckoo, 

 but not the Cuckoo's song. 



3=+l 



? 



CSri.oo. 



The instant I heard 'Cuckoo* . . . giving the in- 

 terval of a fourth, I experienced a thrill of satisfaction 

 such as no similar discovery had afforded. Other ears, 

 sharper than mine, had heard all, unknown to me; 

 and there was great rejoicing, the Cuckoo was learning 

 to sing 1 " But I have long been of the opinion myself 

 that the Cuckoos, all of them, were birds whose voices 

 were set in two distinct tones ; in the case of the Ameri- 

 can species it has simply been a question of its ability 

 to separate or individualize those tones. The European 

 18 



