134 



THE MICROSCOPE 



Another form with a tail like a long Bpine and an eye that 

 fills most of its head is shown in Fig. 130. 



The study of the development of the cell structure in vegetable 

 life is equally fascinating — how cells which in their simplest 

 forms, having all similar functions, group themselves together 

 into colonies. Some of the constituents take on certain functions 

 only, leaving others to accomplish different work, until a complex 

 vegetable growth is built up of cells, all of which have their own 

 characteristics. 



The circulation of the sap in plants can be readily observed. 

 The breathing apparatus of plants where they absorb carbonic 

 acid and liberate oxygen can be found on the 

 under-suiface of most leaves. The hairs of plants 

 form a study in themselves. Fig. 131 shows the 

 hair of the stinging nettle : on the left it is in its 

 undamaged condition. It has a knob on the end, 

 and a closed canal can be seen running up the 

 centre. A light touch knocks ofE the knob, leaving 

 a sharp pointed end which will pierce the skin; 

 and the canal being opened by the removal of the 

 knob, the poison that it contains can enter the 

 prick made by its sharp point. 



The seeds and pollen of plants are wonderful 

 in the elegance of their design and the variety 

 of their structure. 



The spore cases of ferns, with their apparatus like tiny spiral 

 springs for hurling the spores to a distance when ripe, can be 

 found as brown patches on the under-surfaces of the bonds. 



Perhaps nothing wiU create more amusement and interest 

 than the examination of the contents of an open umbrella after 

 it has been held under the bushes, on a hot summer day, while 

 the bushes are lightly beaten with a stick. No one could have 

 imagined what a variety of tiny microscopic insects exist of which 

 most people are entirely unaware. The eyes, legs, wings, pro- 

 boscis, and other parts of the insects should be examined, and 

 the habits of the voracious little creatures will surprise even the 

 naturalist who is used to the curious manners and customs of 

 the larger animals. 



These few notes on the employment of the microscope for 

 the less serious subjects than those from which it is a necessary 

 as a scientific tool, do not do more than indicate a few directions 

 in which enjoyment can be obtained from its use. 



J 



Fig. 131.— 



Nettle Hair. 



