CHAPTER I 

 Life of Plants and Animals 



I. Introductory. 



In this division is given an account of the more 

 fundamental facts of plant and animal life having 

 relation to the subject of nature study, but too difficult 

 for individual discovery from the object by the ordinary 

 pupil in the grades; also a classification of the more 

 common forms of life which will be likely to be used 

 by the teacher in nature study. The principal theo- 

 ries in regard to organic development are also briefly 

 stated, together with theories and standpoints regard- 

 ing human development and their relation to the peda- 

 gogy of nature study. It is thought that the teacher 

 who is able to take an interest in these more difficult 

 phases of her work will be able to get more out of 

 nature study than she otherwise would. 



n. Microscopic Organisms. 



ALGI. In quiet pools of water along the banks of 

 running streams or in tanks of fresh water, and in 

 ditches along the roadside, there is often found during 

 the summer months a green scum floating near the 

 surface of the water. It has a slimy appearance and 

 is therefore called pond-scum. It is a comparatively 

 simple green plant, consisting of an interwoven net- 

 work of threads, which, under the microscope, show a 

 spiral arrangement of the green coloring-matter or 

 chlorophyl, and is therefore called spirogyra. 



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