PROPER TEMPERATURE 63 



the leaves of the plant.*** "It is probable that formaldehyde is first 

 produced according to the following equation. CO2 plus H2O equals 

 CH2O plus O2. Cane sugar (C12H22O11) and starch (C6H10O5J 

 are among the earliest products. These are converted respectively 

 into glucose (C6H1206) and maltose (C12H22011.H20) for the 

 noui-ishment of distant parts of the plant, to which they are conveyed 

 by the movement of the sap. In parts where growth is taking place 

 and new cells are being formed, the sugar of the sap is converted into 

 'cellulose,' the substance which forms the cell walls, and of which the 

 skeleton of the plant primarily consists." 



The fatty matter of the plant is thought to come from the carbo- 

 hydrates. Albuminoids are probably formed from the carbohydrates 

 and the nitrates and then changed to proteids. 



(6) Transports plant food. 



The activity of water in plant growth is incessant and vital. The 

 growing regions depend upon this carrier of plant food in physical 

 solution for their maintenance and continued development. This is 

 a very important function of water in plant life. Water acts as a 

 carrier of waste materials. 



PROPER TEMPERATURE. The average temperature of the 

 native habitat of a plant is an important factor in determining its 

 maximum growth. Yet adaptability to environment has enabled 

 many plants to move far away from their original abode. Corn now 

 grows north of the Minnesota-Canadian line. South Dakota is yearly 

 increasing its production of this cereal. The optimum temperature 

 for the development for different plants varif^s greatly. A cool month 

 of May is detrimental to growth of corn, but small grdn thrives lux- 

 uriantly. A hot, wet July is ideal for corn, but means destruction to 

 spring wheat. 



The following table shows the growth of 25 stalks of corn from 

 June 21 until August 20, 1907. The measurements were in most 

 cases taken every three days. The highest point of the stalk was used 

 as the basis. When the corn was small the highest point was in the 

 crotch where the upper leaves spread away from the central stem. 



