VEGETABLE CYTOLOGY 75 



sugar cane, sorghum, corn and Mexican grass; in many fleshy roots 

 notably the sugar beet; in the sap of the sugar maple and various 

 palms including Cocos nucifera, Phoenix syhestris, Arenga saccharif- 

 era; in various fruits, as apples, cherries, figs, etc., in the nectaries 

 of certain flowers; in honey; and in a number of seeds. It crystal- 

 lizes in monoclinic prisms or pyramids. When sections of plant parts 

 containing cane sugar are placed for a few seconds in a saturated 

 solution of copper sulphate, then quickly rinsed in water, trans- 

 ferred to a solution of i part of KOH in i part of water, and heated 

 to boiling, the cells containing the sugar take on a sky-blue color. 

 Invertase of the yeast reduces cane sugar to dextrose and levulose 

 and zymase of the same plant ferments these forming carbon dioxide 

 and alcohol. 



Maltose is found in the germinating grains of barley and other 

 cereals as a product of the action of the ferment diastase on starch. 

 It reduces Fehling's solution, forming cuprous oxide, but one-third 

 less with equal weights. 



Trehalose or mycose is found in ergot, Boletus edulis, the Oriental 

 Trehala and various other fungi. 



Melibiose is formed with fructose upon hydrolyzing the trisac- 

 charose melitose which occurs in the molasses of sugar manufacture 

 and in Australian manna. 



Touranose is produced upon hydrolyzing melizitose, a trisaccha- 

 rose which occurs in Persian manna, and 



Agavose is found in the cell sap of the American Century Plant, 

 Agave americana. 



2. Starch. Starch is a carbohydrate having the chemical formula 

 of (CeHijOs^ which is generally found as the first visible product 

 of photosynthesis in most green plants. It is found in the chloro- 

 plasts and chroma tophores of green parts in the form of minute 

 granules. This kind of starch is known as Assimilation Starch. 

 Assimilation starch is dissolved during darkness within the chloro- 

 plasts by the action of ferments and passes into solution as a glucose 

 which is conveyed downward to those parts of the plant requiring 

 food. In its descent some of it is stored up in medullary ray cells, 

 and in various parts of the xylem, phloem, pith and cortex in the 

 form of small grains. Considerable, however, is carried down to 



