Lesson XLVI

The Tree-frog or Tree-toad

Leading thought—The prettiest part of the spring chorus of the frog ponds is sung by the tree-frogs. These little frogs have the tips of their toes specially fitted for climbing up the sides of trees.

Method—Make a moss garden in an aquarium jar or a two-quart can. Place stones in the bottom and moss at one side, leaving a place on the other side for a tiny pond of water. In this garden place a tree-frog and cover the jar with mosquito netting and place in the shade. The frogs may be found by searching the banks of a pond at night with a lantern. However, this lesson is usually given when by accident the tree-frog is discovered. Any species of tree-frog will do; but the Pickering’s hyla, known everywhere as the spring peeper, is the most interesting species to study.

Observations—1. How large is the tree-frog? What is its color? Describe the markings.

2. Place the tree-frog on some light-colored surface like a piece of white blotting paper. Note if it changes color after a half hour. Later place it upon some dark surface. Note if it changes color again. How does this power of changing color benefit the tree-frog? Place a tree-frog on a piece of bark. After a time is it noticeable?

3. Describe the eyes. Note how little the tree-frog turns its head to see anything behind it. Describe its actions if its attention is attracted to anything. What color is the pupil? The iris?

4. Note the movement of breathing. Where does this show the most? Examine the delicate membrane beneath the throat. What has this to do with the breathing?

5. What is the tree-frog’s note? At what time of day does it peep? At what time of year? Describe how the frog looks when peeping.

6. How does the tree-frog climb? When it is climbing up a vertical surface study its toes. How many on the front foot? How are they arranged? How many toes on the hind foot? Sketch the front and hind feet. How do the toe-discs look when pressed against the glass? How does it manage to make the discs cling and then let go? Are there any more discs on the under side of the toes? Is there a web between the toes of the hind feet? Of the front feet?

7. Look at a tree-frog very closely and describe its nostrils and its ears.

8. Are the tree-frogs good jumpers? What is the size and length of the hind legs as compared with the body?

9. When and where are the eggs of the tree-frog laid? How do they look?

10. How do the tree-frog tadpoles differ from other tadpoles? Describe them if you have ever seen them. In what situations do they live?

11. Of what use are the tree-frogs to us?

References—“The Life History of the Toad,” Cornell Nature Study Volume, S. H. Gage; The Frog Book, Dickerson; Familiar Life of Field and Forest, Mathews; American Natural History, Hornaday; Elementary Zoology, V. L. Kellogg; From River Ooze to Tree-top, Sharp.