bina, N. D., seem to possess the light median dorsal stripe, although 

 it is by no means universal. Those of Itasca Park, Bemidji, and points 

 further south are more inclined to brown without the light median 

 stripe. Several frogs from Wisconsin have the following characters: 

 The legs are barred with black; there is considerable green in the 

 mottling of the rear of the femur and in the groin; there is rather 

 heavy mottling on the pectoral region and on the lower throat; the 

 hind legs average shorter than in the typical R. sylvatica and the frogs 

 attain breeding characters at a much smaller size than we find in 

 R. sylvatica. 



From examination of material in the National Museum and other 

 museums, we observed that, sometimes in the same lot, there may be 

 individuals of the same sex, one with the mid-dorsal line, one with it 

 absent. In the same way, the light tibial stripe may be absent or 

 present in the same lot. 



Structure: Body stout; legs shorter and stouter than in Rana 

 sylvatica; heel reaching tympanum or eye; tibia 3-4 times as long as 

 broad; tibia 1/2 length of body; back, flanks and lower belly smooth; 

 tympanum smooth; thumb of male enlarged; greater webbing in hind 

 foot of males. 



Voice: The call is a hoarse clacking. It has no external vocal sac 

 and calls from the surface of the water. 



Breeding: They breed from March to July dependent upon the 

 portion of range, March-April in Michigan, May-July in Mackenzie 

 region. Like R. sylvatica the eggs are in masses attached to vegetation. 

 The tadpoles are like those of R. sylvatica. They transform from May 

 25-September 15 at 3/4-7/8 inch (18-22 mm.). 



Notes: Aug. 30, 1930. Pembina, N. D., Red River of the North. 

 The river is low, with a zone of six feet of bare mud inclined, exposed 

 and broken into blocks. Next comes a zone of low weeds and grasses, 

 then dense low willows extend up the bank for two rods or more. It is 

 very dry and baked amongst them. — Above, are upland meadows 

 and cultivated fields. Along the moist edge of the vegetation we took 

 several median-striped northern wood-frogs. We took an adult male 

 with the median stripe half way to vent, a male without median 

 stripe, a female with median stripe from snout to vent, and one with- 

 out median stripe, and several young with and several without the 

 median stripe. All were quite spotted on the breast. The dark pattern 

 on the back was quite conspicuous. This is the finest series of northern 

 wood-frogs we have taken or seen alive. 



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