INTRODUCTION 



A sedge ; the umbrella plant (Cyperus alternifolius) or 

 the Egyptian paper plant (C. papyrus}, so common in 

 greenhouses, will either of them do very well, though our 

 native wild plants are always preferable when they can be 

 obtained. 



Healthy plants of oxalis and tropaeolum. 



A twining vine ; hop, morning glory, kidney bean, etc. 



A glass jar with one or two water plants, such as pond- 

 weed (Potamogeton}, hornwort (Ceratophyllum\ bladdervvort 

 (Utricularia\ or pickerel weed (Pontederia), etc. 



ENGLISH SCALE, 

 FOUR INCHES 



METRIC SCALE, 

 TEN CENTIMETERS 



2. A comparative scale of the English and 

 metric systems of length measure. One decimeter 

 = 10 centimeters = 100 millimeters = approximately 

 4 inches. 



3- A comparative 

 scale of the Centigrade 

 and Fahrenheit ther- 

 mometers. On the Cen- 

 tigrade scale o = the 

 temperature of melting 

 ice, and ICCP = that of 

 boiling water. 



