498 AMERICAN JOURNAL OF BOTANY [Vol. 9. 
Table 2a. Black Border Zone of Decay; Results of Testing the Tissues for Cellulose and Lignin, 
Width of Zone, 1/4 to 1/2 mm. 
Elements Cellulose Test Lignin Test 
Med. ray cells Good cellulose test, but does Slight lignin test as ob- 
not show through brown served in sound wood 
area 
Tracheids and vessels No cellulose test Good lignin test 
Wood parenchyma Good cellulose test where not No lignin 
hidden by brown substance 
Wood fibers Cellulose for mucilaginous Good lignin test for or- 
fibers dinary wood fiber 
Table 2b. Lesser Decay of Wood; Results of Testing the Decayed Tissue for Cellulose and 
Lignin. Sections made Free-hand from Larger Section I 
Elements Cellulose Test Lignin Test 
Med. ray cells Good blue color for ray cells No lignin remaining in ray 
cells, and where present 
very faint 
Tracheids and vessels Deep blue color in tyloses Fair lignin, but not as deep 
red as that in normal 
wood 
Wood parenchyma Fair bluish stain with haema- No lignin present 
toxylin 
Wood fibers.. Still bluish for mucilaginous Fair lignin present 
fibers 
Table 2c. Badly Decayei Portion of Wool; Results of Testing the Decayei Tissue for Cellulose 
and Lignin. Sections both Radial and Tangential, Taken from Section I 
Elements Cellulose Test Lignin Test ^ 
Med. ray cells Very good blue color No lignin present 
Tracheids and vessels Those which are still remain- Scarcely perceptible lignin 
ing give a good blue for the color 
tyloses 
Wood parenchyma Give good reaction for cellu- No lignin 
lose 
Wood fibers Color is absent in the ordi- Give a very faint to color- 
nary fibers and blue is less reaction with a lignin 
present in the mucilaginous test 
fibers 
The results thus speak for themselves. The hyphae have the power of 
dissolving the lignin from the wood by enzymatic action. 
