Voice 



still greater intervals, as in the case of Bufo americanus. This 

 single note may be of any pitch whatever, high or low; and frogs 

 of the same species may give calls of different pitch; in fact, there 

 seem to be two or three prevailing tones in the case of some spe- 

 cies. This is decidedly true of Bufo fowleri and Hyla pickeringii. 

 Again, the note may be smooth and unbroken (Hyla pickeringii), 

 vibrated so rapidly that it reminds one of the buzzing calls of 

 some Orthopterous insects (Engystoma carolinense) , or trilled 

 in a pronounced fashion (Hyla versicolor). The quality may 

 vary as greatly as the pitch, being sweet and musical (Bufo amer- 

 icanus), sonorous and musical (Rana catesbiana), harsh and 

 squawking (Bufo compactilis), like the rattling of pebbles (Acris 

 gryllus), and so on. The character and expression in many 

 cases is easily recognizable: for instance, the song of Bufo ameri- 

 canus is reposeful, almost serene; that of Hyla versicolor sug- 

 gests comfort, just as the purring of a cat does; Bufo Fowleri 

 voices woe and desolation with every note; and Bufo quercicus 

 would seem to be expressing most active distress in its tones 

 like those of a lost chicken. 



Enough to say that these calls of the Salientia are easily 

 recognized after being once heard and identified, and although 

 they are less complex and musical than those of the birds, 

 nevertheless we get much pleasure from the recognition of these 

 primitive songs of a primitive race. They not only act as tol- 

 erably accurate barometers, thermometers, and calendars, but 

 in our travels through new parts of the country announce to us 

 something concerning the fauna of the place without investi- 

 gation on our part. 



During spring and early summer we are likely to hear not 

 the voice of a single performer of a given species, but the com- 

 plex sounds produced by a chorus of performers. The result 

 of the many voices may be a harsh and discordant medley or 

 an effect of harmony, depending on the species, the number 

 singing and the vigor and rapidity with which they are produ- 

 cing the sounds. Rana catesbiana and a few others do not 

 sing in chorus. 



The females, as a rule, produce less loud and emphatic calls 

 than those given by the males. They never show external vocal 

 pouches. In some cases they seem to be voiceless. However, 

 many that were thought voiceless have, during later investiga- 



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