New Yorx AqricutturaL Expertment S@aTtion. 61 
only partially dissolved in the digestive juices. It follows, then, 
other things being equal, that the larger the proportion of starch 
and sugar in the nitrogen-free extract of a feeding stuff the more 
completely is it digested. 
It also follows that when any manufacturing or other process 
reduces the proportion of sugars and starch in any grain or other 
material, the digestibility, and consequently the nutritive value 
of its non-nitrogenous part, is diminished. We have good rea- 
son for believing too, that the net value of that which is digested 
is less than would be the case if the proportion of starch and 
sugar had not been reduced. 
While the digestion products of fiber and gums are undoubtedly 
oxidized quite fully and perhaps furnish to the animal their full 
calorimetric value (except a small proportion of expiratory methan 
supposed to come from the fiber) the elaborate researches of Zuntz 
leave little doubt that their net value is less than digested sugars 
and starch. This is because the work of mastication and digestion 
of the former is greater. 
As a matter of ilustration we may refer to the great superiority 
of corn meal over timothy hay in point of digestibility, the ex- 
planation of which is in accordance with the facts just stated. 
The nitrogen-free extract of maize is mostly starch, the accom- 
panying fiber being insignificant in amount whereas in timothy 
hay there is found a small proportion of sugars and starch, while 
gums, fiber and other less digestible compounds are abundant. 
Moreover, because of the more resistant qualities of the hay to 
mastication and propulsion along the alimentary canal, it costs 
more to digest it than is the case with maize and other grains. 
Practice recognizes these facts in its estimate of the grains as 
against the fodders. 
