Rana septentrionalis 405 



7. Males probably do not breed until two years from transformation. 

 In our series we have no positive male (externally) before 50 mm. 

 In the U. S. National Museum series is one 48.5 mm. Of one speci- 

 men in our series, 46.5 mm., we record that it "begins slightly to 

 show maleness in tympana and thumbs." 



8. In like fashion the females do not breed until two years from 

 transformation. In our series the first positive female is at 50 mm. 

 In the U.S. National Museum series we recorded in Miller's speci- 

 mens from Peterboro, N. Y. a 9 47 and a 9 48 mm. In our own 

 material we have one questionable female at 48 mm. 



9. The range of size for positive breeding males is from 48.5-66 mm., 

 for females from 50-72 mm. 



Duration, night or day. The mating habits of this species still rest on few 

 observations. The period of mating begins in the latter part of June and 

 extends well into August. Garnier (1883) found eggs June 24 and July 30. 

 Norton records frogs then calling August 15-16, 1914. Possibly June 24- 

 August 16 represents the range of the mating period. In general the bulk 

 of mating must come from June 2 8- July 30. In 19 13 the choruses at Otter 

 Lake, Ontario, were from July 7-15. This year (1923) at Onekio, N. Y. 

 they were not mating June 14. On June 28 at Adirondack Lodge, Hart 

 Lake, Messrs. S. C. Bishop and C. K. Sibley found them in chorus and the 

 males very impulsive but no eggs present. About July 7 Mr. C. W. Leister 

 also heard them at Hart Lake as did Mr. and Mrs. G. B. Upton indepen- 

 dently. On July 14 I found the species mating and breeding at Hellgate 

 ponds, Onekio, N. Y. My friend Dr. S. C. Bishop at Hart Lake also found 

 them breeding there July 14. About the same time July 8, 1923, Dr. S. E. 

 Simpson at Otter Lake, Dorset, Ontario, reports by letter that he had recently 

 found them breeding. It would, therefore, appear that July 7-15 is an almost 

 certain mating date for this species if three of us independently find the eggs 

 July 8-14. 



This species usually is most active at night. On July 14 I saw about 

 9:30 a.m. six or eight males spread out on the surface around a mass of 

 sedges. They were vigorously croaking and from time to time rushing at 

 each other, the rushee thinking the other to be a female. They lie spread out 

 with hind legs on the surface. On July 2, Messrs. Bishop and Sibley took 

 on Clear Lake "24 specimens of which 23 were males and one juvenal female. 

 These males were swimming and floating in open water 3 or 4 rods from shore 

 or resting on pads of the yellow cow lilies. " On July 13 and 14 we have the 

 following notes from Dr. S. C. Bishop. On July 13 he "took two mature 

 females; one specimen with eggs extruding was resting at the surface of the 

 water with no male in her vicinity; the other female was at the surface and 

 near the shore. On July 14 placed at 9:00 a.m. a male with first female 

 (extruding eggs) in a pan and kept dark. By 9:30 they were mated and so 

 remained until 2:00 p.m. when the female was found to be dead. The male 

 grasped the female with the first two fingers above and in front of the brach- 

 ium and the other two fingers behind the brachium. Later the male had 

 one arm wholly ahead of the female." 



