PART II 

 COMPOUND CELLULOSES 



IN dealing with the isolated celluloses it has been shown that 

 the processes by which they are isolated or purified are based 

 upon the relative reactivity of the compounds with which the 

 celluloses are combined or mixed, in the raw or natural 

 products of plant life. These natural forms of cellulose are, of 

 course, multitudinous. Remembering the infinite variety of 

 the vegetable world, the endless differentiation of form and 

 substance of the tissues of plants, it might be presumed that 

 the chemical classification of these products would present 

 unusual complications. 



Investigation, however, has shown, and continues to show, 

 that this great diversity of substance, as revealed by proximate 

 analysis, exists upon a relatively simple chemical basis. The 

 compounds constituting the fundamental tissue of plants may, 

 in fact, be broadly classified in correspondence with the three 

 main types of differentiation of the cell wall long recognised by 

 the physiologists, viz. lignification, suberisation, and conversion 

 into mucilage. That is to say, in addition to the celluloses 

 proper and hemi- or pseudo-celluloses which may be defined 

 as polyanhydrides of the normal carbohydrates, ketoses and 

 aldoses there are three main types of compound celluloses in 

 which the celluloses as thus defined exist in combination with 

 other groups, as follows : 



Lignocelluloses. The substance of lignified cells and 



