132 ECONOMIC ZOOLOGY 



It usually requires three or four years for frogs to reach maturity 

 and it is generally supposed that they may live for 15 or 20 years. 



One danger to eggs and tadpoles that cannot well be eliminated by 

 frog culture is from late cold spells that may freeze the shallow pools 

 and kill large numbers of the inhabitants. 



The Bufonidce include over a hundred species of toads belonging 

 chiefly to the genus Bufo; over a dozen representatives of this genus 

 have been found in North America. 



The common toad of the eastern United States, Bufo lentiginosus 

 Americanus, Fig. 94, is familiar to all as the clumsy, warty animal that, 



FIG. 94. The American toad, Bufo lentiginosus americanus. X%. 



after hiding in some dark nook all day, hops out, toward dusk, to seek 

 his food during the night. Being an ugly animal the toad, in olden 

 times was considered highly venomous, as noted by Shakespeare and 

 other more ancient writers, and a remnant of these superstitions is 

 seen even now in the very common and entirely erroneous belief that 

 warts may be caused by handling toads. As a matter of fact, however, 

 the glandular warts so characteristic of the toad do secrete a substance 

 that protects them quite largely, from being eaten as are the other 

 members of the Urodila, though the flesh is said not to differ appreciably 

 in taste from that of the Ranidae. 



