The Western Frog 



margins. It appears in the Puget Sound region from the last 

 of February to the middle of March. A few scattered individuals 

 may, however, be seen on sunny days throughout the winter. 

 These are usually among the lily-pads along the marshy borders 

 of the lakes. 



As soon as they appear in March, they set up a noisy croak- 

 ing, and the eggs are laid between this time and the first of April. 

 The egg-masses (Fig. 261) are unattached. They vary greatly 

 in size, but average about a pint in bulk. In one case where 

 the eggs were counted, a laying consisted of over fifteen hundred 

 eggs. The eggs are relatively large, measuring nearly 2 mm. 

 in diameter. Each egg is in a transparent sphere of jelly meas- 

 uring one-half inch across. The eggs are placed in the shallow, 

 marshy pools near a lake, but never in the deep lake-water itself. 

 The length of time required for hatching is from one to two weeks, 

 varying with the temperature; those in the warm, shallow water 

 hatching earlier than those in deep water. The later develop- 

 ment is slow, and it is not until after the summer is passed that 

 the tadpole becomes a frog. This slow development is perhaps 

 correlated to the conditions of the region of the frog's range. 

 There is an abundance of water in this region, even in summer, 

 so that the development is not hastened by the drying up of the 

 pools. 



From this time on the growth is slow; at least, there can be 

 found, each spring, frogs of four or five different sizes, so that it 

 would seem as though they require four or five years to reach 

 the adult size. 



The adults are easily captured during the breeding-season. 

 As soon as we approach them, they dive into the mud of their 

 shallow pool, burying the head and shoulders, but leaving the 

 legs exposed in good position for capture. Their colouring is 

 highly protective. It is difficult to see them when they are 

 sitting among the alternating lights and shadows of the reeds. 

 They depend so much on their protective colouration, that they 

 lie low and allow themselves to be touched before taking alarm. 1 



This frog is distinguished from other Western frogs by its 

 round nostrils, the tubercular character of the soles of the feet, 

 the long foot and large web, and the lack of prominent lines 



1 Many facts concerning this species were kindly furnished by Prof. J. F. Tiling worth, Seattle, 

 Wash. 



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