SCIENCE IN THE OPEN AIR. 



II 



wires placed at equal distances forming the sides. In it was a large cricket 

 beside a leaf of lettuce, which served as his food (fig. 4). The little 

 creature moved up and down his prison, which was suspended from the 

 branch of a tree, and when one approached him very closely gave vent to 

 his lively chirps. 



The menagerie was soon further augmented by a hitherto unthought-of 

 object ; namely, a frogs 1 ladder. It was made with much skill. A large 

 bottle served for the base of the structure. The ladder which was fixed in 

 it was composed of the twigs of very small branches, recently cut from a 



Fig. 6. Frog lying in wait for a fly. 



tree, and undi vested of their bark, which gave to the little edifice a more 

 picturesque and rustic appearance. The pieces of wood, cleverly fixed into 

 two posts, conducted the green frogs (tree-frogs) on to a platform, whence 

 they ascended the steps of a genuine ladder. There they could disport 

 themselves at pleasure, or climb up further to a branch of birch-tree placed 

 upright in the centre of the bottle (fig. 5). A net with fine meshes pre- 

 vented the little animals from escaping. We gave the tree-frogs flies for 

 their food, and sometimes they caught them with remarkable dexterity. I 

 have often seen a frog when at liberty watching a fly, on which it pounces 

 as a cat does on a bird (fig. 6). The observations that we made on the 



