286 



Mary Davies Swartz, 



37° C.,it is further hydrolyzed and yields then 16.9-20.4 per cent sugar. 

 The results of Lohrisch's experiments appear in the folowing table: 



Lohrisch (194) has also studied the utilization of agar-agar in starv- 

 ing herbi'vora. In two experiments, rabbits starved for two days 

 were fed ordinary agar as long as they would eat it, other animals of 

 the same weight being kept in starvation as controls; in a third expe- 

 riment, " soluble agar" was fed. Urine and faeces were collected and 

 analyzed. Of the ordinary agar, about 50 per cent was excreted in 

 the faeces; of "soluble agar," about 25 per cent. No positive evidence 

 of any change in nitrogen excretion attributable to the agar fed, can 

 be drawn from the protocols. One animal died through accident, 

 another survived its control but one day, and the third, in spite of its 

 apparently good digestion of the "soluble agar," died a week before 

 its control. 



In the case of rabbits made diabetic with phlorhizin and then fed 

 20-40 grams of both ordinary and soluble agar, Lohrisch (194) found 

 that the D : N ratio remained fairly constant throughout each experi- 

 ment, showing no marked increase in sugar excretion. We see, there- 

 fore, no grounds for assuming that agar-agar {galactan) forms glycogen 

 in rabbits. 



The first studies on the utilization of ga'actan by man were made 

 by Saiki (205) (1906). In feeding experiments in which various car- 

 bohydrates were at different times added to a uniform diet, consisting 

 of 513 grams beefsteak, 500-600 grams bread, 40 grams sugar, 31 

 grams butter, 2 eggs and 2 apples — a diet on which over 98 per cent 

 of the carbohydrates were digested, he obtained the following results: 



