AGRICULTURAL EXPERIMENT STATION. 15 



obtain some idea as to the digestibility of these bodies by including 

 these methods among the analytical processes controlling an ordi- 

 nary digestion experiment. 



One of us has already published the results of a brief digestion 

 experiment with rabbits, from which it appeared that in a normal 

 ration about sixty per cent, of the pentosans were digeslec 1 It was 

 also noticed that the proportion of pentosans to the entire amount 

 of nitrogen-free-extract was much increased in the fasces as com- 

 pared with the food. These results, however, being based upon 

 meagre data, had little more than a suggestive value, as showing 

 the importance of further study in the same direction. The present 

 paper adds a considerable amount of proof to the previous one 

 without materially changing the conclusions then drawn. 



Some months since, Professor W. H. Jordan, Director of the 

 Maine Experiment Station, placed at our disposal a large number 

 of control samples of the food and fasces from digestion experi- 

 ments, carried on by him during a series of years. These samples 

 had been carefully preserved in air-tight vessels and reached us in 

 excellent condition. We have determined the pentosans in these 

 samples and from the feeding data furnished us by Professor Jor- 

 dan, we are enabled to report upon their digestibility in twent} r 



different experiments The errors of the analytical 



methods and of the assumption upon which the calculations are 

 based, are all such as to minimize the actual results. In the same 

 direction, we have presented here the lowest results obtained from 

 duplicate determinations in each case. The data, here given indi- 

 cate, therefore, the minimum amounts of pentosans found, so that 

 the results of future study and perfected methods will, we believe, 

 emphasize rather than diminish the conclusions here drawn. 



The materials used in the digestion experiments were in part, 

 selected samples of single species of grasses grown for the purpose 

 at the Maine Experiment Station, and the samples were typical of 

 our forage grasses. It is of preliminary interest, therefore, to mark 

 the extent to which the pentosans occur in these and other mate- 

 rials of common and frequent use as cattle foods. 



The furfurol (i. e. pentosans) was determined in each sample in 

 duplicate by separate distillations. The lowest of these results 

 was then multiplied by the factor 1.38 to convert it into a value 

 representing pentosans. For comparison, the percentages of nitro- 

 gen-free-extract matter as given in Professor Jordan's report, are 

 repeated here. All numbers relate to the dry matter. 



