began to swell out his sacs back of his ears as are the sacs of R. pipiens 

 and R. virgatipes. ... I put them in a bag and carried them on my 

 belt. A few times they gave semi-croaks which reminded me in some 

 ways of R. palustris. . . . Once or twice I heard a very low croak. It 

 must have been Rana onca. 



Breeding: It probably breeds in the spring. The eggs are not 

 known. The general color of the tadpole is dull citrine with the tail pale 

 green yellow. The tail is elongate, its tip rounded. The largest tad- 

 pole we caught was probably not mature, being i 5/8 inches (42 mm.) 

 and of the R. clamitans type. The tooth ridges are 2/3. We caught no 

 specimens at transformation. The smallest frogs we saw were 1 9/16- 

 1 5/8 inches (39-42 mm.). 



Notes: August 20, 1925. Las Vegas, Nev. We went out the Tona- 

 pah road . . . Then we turned back and about 3 miles from Las 

 Vegas passed an artesian well pouring out a big stream of water, 

 and then came to a low swampy area with quite a stream rushing 

 on one side of it. No frogs were seen here. We drove a short distance 

 to where on both sides of the road small springs came out of the 

 ground in basins 3-4 feet across and ran as trickling streams down 

 into the field. These had been artificially ditched. The streams were 

 covered with algae. The region was grassy with a stiff grass. The im- 

 mediate edges were sedgy. I first saw a frog jump into the tiny stream 

 . . . just showing through a break in the algae. We caught him. He is 

 the game we came for, Rana onca. Then across the road we found a 

 large male near the spring hole . . . We found tadpoles in the spring 

 hole. Two hundred and fifty extra miles of desert for a frog seems 

 worth it when you find your game. W 7 e followed one tiny stream back 

 into the field and returned with the trophies, 6 R. onca y 4 Hyla regilla, 

 and 1 Bufo compactilis. The second frog we caught was in one of the 

 headwater springs and was resting against the bank with 1 1/2 inches 

 of its head out. When I started to catch it, it swam only a short dis- 

 tance, didn't go into the bottom at all, just rested on the top of the 

 bottom. I moved away the scum over it and yet it stayed in position. 

 Then with a pan we began to scoop the area along the edges. The frog 

 came to the top. They are very easy to capture, not what I would 

 call extremely alert. 



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