SUMMARY. 109 



The lignified cell-wall is one which is so modified that it is hard, inelastic, 

 and is easily penetrated by water. 



The mineralized cell-wall is one which is hard from the deposition 

 of mineral matters. 



The mucilaginous cell-wall is one which becomes gelatinous when it 

 absorbs a large quantity of water. 



The protoplasm is usually a semifluid substance consisting of albuminous 

 matter, water, and a small proportion of ash-constituents. 



Primordial cells are those which are destitute of cell-walls. 



The cell-sap is a watery solution of various substances and usually makes 

 a large sapcavity within the protoplasm ; it also saturates the cell-wall and 

 all the other organic structures of the cell. 



The chlorophyll-corpuscle is a green body which consists of a coloxirless 

 mass of the protoplasm distributed by a small quantity of a green colour- 

 ing matter called chlorophyll. 



The starch-grain is a minute body which has one or more central points 

 surrounded by concentric layers and consists of starch, water, and a small 

 proportion of ash-constituents. 



Starch-grains are said to be simple when they are provided with but one 

 central point. 



Starch-grains are said to be compound when they are provided with two 

 or more central points. 



Crystals are mostly formed of calcium oxalate and rarely of calcium 

 carbonate. 



Parenchymatous cells are those which are not much longer than they are 

 broad and have rounded or flattened connecting surfaces. 



Prosenchymatous cells are those which are long and spindle-shaped. 



Vascular cells are those which are tubular from the absorption of their 

 transverse walls. 



When new cells are formed by the division of a mother cell into two 

 parts, that mode is known as cell-division. 



When one or more new cells are formed within a mother cell, that mode 

 is known as interior cell-formation. 



When a single new cell is formed by the coalescence of the protoplasmic 

 contents of two or more cells, that mode is known as conjugation. 



