comparisons include such intriguing ones as a steam calliope, the groan of a 

 deep-voiced man having a tooth pulled, the squawk of a big rooster caught in the 

 night, the distant honking of geese, and the cawing of young crows. 



When the females have entered the ponds, a peculiar mating called 

 amplexus takes place. A male grasps a female with his fore limbs, in most cases 

 gripping her just behind her arms, and swims with her. This embrace may help 

 to force the eggs from the body of the female. At the same time the male 

 ejects sperm, which fertilize the eggs as they are discharged into the water. In 

 the spadefoot toads the embrace is not axillary but inguinal, the female being 

 grasped at the waist. A small pond full of mating frogs or toads is literally a 

 battleground, for the males compete vigorously for their amatory privileges. 

 Sometimes an unfortunate female is gripped by as many as three or four persist- 

 ent males, so that she is submerged beneath the surface of the water by the com- 

 bined weights of her admirers. Apparently the males distinguish the females 

 by a process of trial and error, for a pursuing male will grasp a female or an- 

 other male with equal readiness. A captured male's protesting croak, the slim- 

 ness of his body, or some other indication warns the captor that he has made 

 a mistake, whereupon the latter quickly relinquishes his hold to try his luck 

 again. 



The eggs make only a small mass when first laid, but the almost invisible 

 coating of jelly around each egg quickly takes up water and swells until it 

 is at least as thick as the width of the enclosed egg, trebling the diameter of 

 the total. The dark colored eggs absorb heat readily and the jelly envelope or 

 envelopes around each egg act as tiny greenhouses, trapping the heat of the sun, 

 so that development proceeds even among fragments of floating ice. Most 

 frogs lay their eggs in clumps. The spring peeper and the cricket frog usually 

 scatter their eggs singly among the submerged vegetation. The true toads de- 

 posit long, curling strings of jelly containing the eggs in approximately linear 

 arrangement. 



In the northeastern states the wood frog, Rana sylvatica, is usually one 

 of the first to lay. This species is peculiar in that the majority of the frogs 

 in the pond deposit their eggs in the same spot, and, where the terrain is such 

 that the spring thawing releases most of the frogs from their land hibernation 

 quarters at one time, the egg-laying period lasts for only a few nights. In a 

 large pond it is not unusual to find almost all the bunches of wood frog eggs 

 clustered in a circle about ten feet across. Naturally, in more rugged country 

 cut by shaded ravines, the release from under frozen debris is more gradual and 

 the frogs are not all able to reach the pond at the same time. In that case the 

 egg masses are less likely to be grouped in one part of the pond. Both the wood 

 frogs and the peepers most often deposit their eggs in temporary ponds, and 

 their tadpoles develop rapidly and transform into frogs by mid-summer, when 

 the pond usually dries. This selection of temporary ponds frees the tadpoles 



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