INTERCELLULAR SUBSTANCES AND WALLS 



69 



All of the angiosperms studied (save Elodea) fall into a common 

 group with respect to their dioxane-soluble lignin. The lignins 

 of this fraction give typical lignin color tests and, to the extent 



Table 1. Classification and Features of Test Species 



that comparisons have been made, possess similar carbon, hydrogen, 

 and methoxyl contents. They are quite similar spectrophoto- 

 metrically (Table 2). 



Among the other species, Polyporus sporophore lignin most 

 closely resembles that of the angiosperms, however the dioxane 

 extracts of Psilotum, Equisetum, and Selaginella are not too dis- 

 similar in ultraviolet spectrum to angiosperm extracts. Only the 

 apparently specialized lignins of Polytrichum and Jungermannia 

 differ markedly in their absorption characteristics. 



