1 62 Lessons in Nature Study. 



In No. 2 put the smallest polliwogs. 

 " " 3 " " larger ones. 

 " " 4 " " first signs of legs. 

 " " 5 " " later leg development. 

 " " 6 " " diminishing tail. 

 " " 7 " " perfect frog. 



This collection shows every stage in the development of 

 the frog, and is always on hand for reference. 



Similar collections to illustrate the metamorphosis of in- 

 sects are always of use in nature study. 



THIRD WALK. 

 TREES. I. 



Take your pupils out for a walk. Make it a short walk, 

 proportioned to the age of the pupils. The lowest grades 

 should never go far beyond the school-grounds. There is 

 abundance of material there. A higher grade may go short 

 distances. The pupils of still higher classes may venture a 

 half mile or farther. 



Make the walk interesting. Let nothing escape the 

 attention. 



See how the tree yonder has a trunk that runs upward 

 through the branches to the very top. Yonder is a tree 

 whose trunk is all broken up into branches. Note how 

 some branches ascend, others are horizontal, others arch, 

 and others droop. 



Call attention to rjie various hues of green in foliage the 

 whitish green of some willows, the dense green of oaks, the 

 tender green of maples. Teach them to observe the gray 

 bark of the beech, white birch, rough black oak, and smooth 

 ruddy cherry. 



After walking some distance ask all to be seated. Let 

 us sit under this fine old tree. See how the roots 

 spread out over the ground. Do you think its roots are as 

 large as its branches ? Why do its roots spread out so ? 

 To gather food and moisture, and to hold the tree firmly in 



