THE ALUMNI JOURNAL 



267 



PLANT CONSTITUENTS. 



By HENRY KRAMER, Ph. G. 

 {Continued from September issue ) 



XV. Ferments are of two kinds : (1) 

 Orga?iized, as bacteria and yeast ; (2) 

 Unorganized ferments which may be 

 divided into (a) Starch or Disastatic Fer- 

 ments, as diastase ; (b) Glycoside Fer- 

 ments, as emulsin and myrosin ; (c) Cane 

 Sugar Ferments, as invertin ; (d) Prop- 

 teid or Peptic Ferments, as in Carica pa- 

 paya. XVI. Alcohols are of two kinds : 

 (1) Fatty, as mannite (C 6 H u 6 ) and (2) 

 Aromatic, as saligenin (C,H 8 2 ). XVII. 

 Acids may likewise be considered as of 

 two kinds : (1) Fatty, as valerianic acid 

 (C 6 H 10 o 2 ) ; caprylic acid (C 10 H 20 O 2 ) ; (2) 

 Aromatic, as benzoic (C 6 H B COOH), citric 

 [C 3 H 4 (OH)COOH], malic [C 2 H 3 (OH) 

 (COOH) 2 ] and aconitic [C 3 H 3 (COOH) 3 ] 

 acids. XVIII Aldehydes, as ciunamic 

 aldehyde (C 9 H g O). XIX. Esters, as 

 cinnamein or benzylic cinnamate [C 9 H, 

 (C,H 7 )0 2 ], styracin or cinnamyl cinna- 

 mate [C 9 H 7 (C 9 H 9 )0 2 ] . XX. Resins may 

 be divided into (1) Oleoresins, as copaiba 

 and gurjun ; (2) Balsams, as balsam of 

 Peru, balsam of Tolu ; (3) Gumresins 

 like asafoetida and myrrh ; (4) True Re- 

 sins, as benzoin, colophony and guaiac. 

 XXI Other plant constituents, as cutin, 

 suberin, lignin, bast, etc., which consist 

 of C, H and O. 



Before we can study these constituents 

 or groups of principles it will be neces- 

 sary to consider briefly the environment 

 of the plant and its food. The vegetable 

 kingdom is divided into two great classes 

 of plants, viz. : those possessing chloro- 

 phyll, and those without chlorophyll. 

 The higher plants are distinguished from 

 the lower in possessing a greater differen- 

 tiation and in being fixed to one place in 

 the soil. These higher plants may 

 flourish in dry soil or may live in the 

 water (aquatics). If any of these higher 

 plants are examined, they will be found 



to possess numerous openings (stomata 

 in leaves and lenticels in the bark) for 

 obtaining air. This air may be used as 

 food by the plant, or for breathing, and 

 in the case of marsh plants which are 

 provided with very large intercellular 

 spaces it is probably also used to prevent 

 the total submergence of the plants. The 

 air is a requisite to the plant life. It is 

 further observed that if a plant is de- 

 prived of water too long it ceases to 

 grow and finally wilts. Growing parts 

 of plants contain from 60 to 90 per cent, 

 of water, and some fungi contain as high 

 as 92 to 98 per cent. Finally it is ob- 

 served that if a phytomer is cut from a 

 hardy perennial and placed in soil under 

 the proper conditions it will grow and 

 produce a new plant. But if a similar 

 phytomer is placed in the air, or in water 

 and air without any soil, it will die. 

 Hence the question arises, what is there 

 in the soil required by the plant ? 



Soil is formed by the alteration of ig- 

 neous rocks, and in them we find the 

 sources of the minerals that enter into 

 soils. These minerals are principally 

 quartz, the felspars, the micas, the am- 

 phiboles, the pyroxenes, olivene, leucite, 

 nepheline, magnetite. These decay 

 (with the exception of quartz) under the 

 influence of the atmosphere and water 

 and become hydrated silicates, carbon- 

 ates and hydrous oxides. If to these are 

 added limestones and dolomites we have 

 the principal rock soils. According to 

 the varying nature of the rocks so are 

 the soils different. There are sandy sails 

 (from sandstones), calcareous soils (from 

 limestones), aluminous soils (from schis- 

 tose rocks), and also gravels, marls and 

 peaty soils. The physical properties of 

 a soil according as it is impervious, stiff 

 and heavy, or porous, pliable and light, 

 are of considerable importance, as they 

 indicate whether it is a retainer of mois- 

 ture or a quick drainer. Rocks that are 



