FROGS. 35 



of the leopard frog is more or less true of the pickerel frog, A capital 



Elace to secure transformed and half-grown pickerel frogs is along the 

 anks of the headwaters of our clear streams. (See fig. 2 and Pis. 

 XXI, fig. 3, and XXII, fig. 7.) 



The newly transformed green frogs vary in length from 1.1 to 1.5 

 inches, the average being 1.3 inches. Most of the transformations 

 occur in the latter part of June and throughout July. Usually, by 

 the first of August transformation for this species is largely, but not 

 wholly, completed. In a species which lays from the last of May to 

 the middle of August, or later, it is evident that some transformations 

 may occur at any time within the same limits. This form spends one 

 winter in the tadpole stage and is a year old before it changes to the 

 frog form. Of all the commercial forms, this has proved the hardest 

 to collect in numbers at the transformation stage. The long period 

 of transformation, the smaUjiess of some of the ponds and of tlieir 

 green-frog tadpole content, and the shyness of the species make it 

 more difficult to secm'e a quantity of young green frogs than a similar 

 number of yomig bullfrogs. It does not seem at present a convenient 

 starting point in the culture of the green frog. (See fig. 2 and Pis. 

 XXI, fig. 2, and XXII, fig. 3.) 



The bullfrog tadpole spends two winters as a tadpole. Inasmuch 

 as the eggs are small and deposited late in the season (usuall}?" the last 

 of June or in July), the tadpoles are small when winter arrives. The 

 whole of the next season is consumed in growth, and it is not until 

 another winter is passed that the larvae begin to approach transf(^r- 

 mation, which usually comes in July — that is, two ycai's after egg 

 deposition. More rarely does the tadpide spend a third winter before 

 transformation. According to all of our data, transformation occm's 

 in July or later. An average of the first dates recorded places the 

 beginning of transformation at July 15, The species evidently does 

 not begin transformation before July 1, and the period of transforma- 

 tion often extends to August 15. In one year, when first recorded 

 on July 30, tadpoles were found which would require two weeks more 

 before transformation. In another year several were found trans- 

 forminsj on August 20, and a few other tadpoles which appeared as if 

 they might transform in October or November or during the next 

 season were found. The mature tadpoles begin to come out in the 

 shallow water in early summer. Here they hide in the Chara, NiteUa,. 

 hornwort, water milfoil, etc., or they rest beneath the lily pads, pond 

 weeds, and other sm'face plants. Another favorite place of trans- 

 formation is among the pickerel weed, arrowhead, and water plantain, 

 which afford an overhead cover. Occasionally, around ponds where 

 shallows are absent, stumps of trees, fallen logs, and trees fringe the 

 edge, and their roots extend out into the water. These are favorite 

 transformation sites for the species. At this period they are present 

 in hundreds, or even thousands. The transformed individuals present 

 a spirited sight as one approaches. They are shy, and long before 

 one gets within range start skipping over the vegetation, giving the 

 alarm note so characteristic of the species when surprised. Equally 

 interesting is it when they occupy perches along the stumpy edges of 

 deep ponds. It seems as if a wave of little bullfrogs keeps going 

 before one as he skirts the pond. Inasmuch as this species requires 

 two years to matm'e, it might naturally be expected tliat with vary- 

 ing conditions the tadpoles would be of diverse sizes at transforma- 



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