Nutrition Investigations. 



323 



for fructose, the polysaccharide of which also appears to be common 

 in algae, but the absence of fermenting sugar in all the algae except 

 Limu Lipoa, indicates that if present, it is in too small amount to be 

 detected in the hydrolysis products of 5-10 grams of crude material. 

 The reducing power has been determined on each substance used in 

 feeding experiments; the results of all determinations are summarized 

 in the following table: 



Bacteriological Investigations. 



introduction. 



It is an accepted fact that even cellulose, with its high powers of 

 resistance, is to some extent decomposed in the alimentary tract by 

 bacteria. It is therefore reasonable to expect that the less resistant 

 hemicelluloses will also be attacked and decomposed by bacteria. 

 The object of these experiments has been to throw some light on the 

 problem as to what organisms are most likely to effect such a decom- 

 position, and whether there is an appreciable production of sugar as 

 a result of bacterial activity. The four classes of hemicelluloses under 

 special investigation have been represented by the following sub- 

 stances: 



Pentosans Dulse. 



/ Irish Moss. 

 ' \ Limu Manauea. 



Galactans . 



Mannans Salep. 



Levulans Sinistrin. 



