CARBOHYDRATES OF THALLOPHYTA AND BRYOPHYTA 61 



leaves from the stems. The tissues had therefore to be 

 immersed in absolute alcohol to check inversion changes. 

 The green portions of the stems were rejected, and are not 

 included in the analyses of either leaf or stem. 



TABLE XXI. 



SUGARS OP POLYTRICHUM. 



Ratios. 



The abundance of sucrose in the leaves as compared 

 with the stems appears to favour the view of Brown and 

 Morris, that it is the first sugar to be formecTin photosyn- 

 thesis. The analyses, however, furnish no evidence for or 

 against Campbell's suggestion that hexoses are found at 

 first, but soon reach a maximum due to their transforma- 

 tion into sucrose. In the stem sucrose appears to be 

 rapidly converted into starch, or it is perhaps inverted to 

 a considerable extent. 



TABLE XXII. 



SUGARS OF THUIDIUM. 



