The Common Bullfrog 



Not only is he alert in sight and hearing, he is ready in muscle 

 for a sudden movement at any second. If a dragon-fly skims 

 over the water's surface in front of him, the insect is swallowed 

 quickly. If a sparrow comes for its daily bath beside what seems 

 to be a moss-covered stone, its brown tail feathers are seen a mo- 

 ment later protruding from the frog's mouth, while the frog is 

 sitting sedately in just the same spot. Sometimes a bird drops 

 from the overhanging bough above, because of the correct aim of 

 some gunner and becomes a trophy for the frog instead of for the 

 man. 



However, it is not appetite alone that brings into play the 

 alert senses and muscles of the Bullfrog. Let a bear approach 

 from the wooded shore ever so stealthily, when his paw comes 

 down suddenly over the frog, he finds he has nothing but water- 

 weeds and mud to pay him for his trouble. 1 A heron hunting 

 frogs has no chance of catching the Bullfrog, if the frog is on the 

 bank. It is only when the Bullfrog is in the mud that he is 

 speared by the powerful beak. Ages of generations of contest 

 with this enemy have not taught the frog to bury the hinder por- 

 tion of his body when he plunges into the mud. He may not see 

 the snake, his greatest enemy, and so, at last, he is lost. But 

 what eyes could see its sinuous body moving so cautiously, neither 

 shape nor motion differentiated from the surrounding water and 

 the waving plant stems? 



And so, in pond and marsh, the contest goes on, as it always 

 has in past ages. Each day the life of the individual is given to 

 maintain the life of the species, and the balance of life among the 

 races is kept, although the scales may tip somewhat now in one 

 direction and now in another. Very definite and very emphatic 

 is our admiration for the individual. Each represents high spe- 

 cialization along a given line of development, and seems perfected 

 to the minutest detail in its fitness for its life. Each is so invisible 

 in its environment that it seems wonderful that an enemy ever 

 finds it at all. Each is supplied with the power of extremely rapid 

 movement. However, certain characteristics may be of the 

 greatest advantage to a given individual, but of the greatest 

 danger to that individual when the same powers are possessed 

 also by an enemy. Thus the rapid flight of a bird or insect is 



1 William J. Long. 



239 



