THE FOOD AS A SOURCE OF ENERGY. 295 
The results on starch, expressed in Calories per gram of organic 
matter, may be summarized as follows: 
Apparent 
Gross Metaboliz- | Per Cent. 
Energy, able Metaboliz- 
Cals. Energy, able. 
Cals. 
Kithn’s Experiments : 
Sample 1, Ox ET icsanas a tae ge akin oan 4.249 3.029 71.21 
DV ies syste oetnacaietay pace iararesease: 4.249 2.705 63.71 
Average.. HIgkennag eee La BRT Me aS 4.249 2.867 67.46 
-‘Sample II, Ox V, Period 2a............. 4.236 3.347 78.95 
- > OE EE DD iacesied we plasuan des 4.236 3.161 74.68 
a : MEG Se? S2 bas ieee gration 4.236 3.018 | 71.26 
ii a ee ree iacise eo 4.236 2.964 69.98 
AV OPA OL fein asstesinusutues sictonsnd Gausmeec sien 4.236 3.123 73.72 
Average of Land II...............00- 4.243 | 2.995 | 70.59 
Kellner's Experiments : 
Samples I and II Ox B................. 4.165 2.027 48 62 
Be Eee ee ON si dona Geen insnuiadk one 4.165 2.028 48 .68 
Average.......... ee 4.165 2.028 48.65 
Sample IIT, Ox Duicciscsasesssas cesses 4.156 2.792 67.20 
s EE LT cls See So es aaa gaanapeeven 4.156 2.969 71.44 
a Bi CMT a» Cnlaseua cite tinea Qi euaceauauncetels 4.156 3.214 77.32 
SAV ETAP CLs a nieane ase doaisl gusledea sl aoiedeenie apa 4.151 2.992 71.99 
Sample IV, Ox Fo... ea. ceca ina eens 4.180 3.313 79.22 
ef FO = SESE) haa tans nahsceses sen Ge Gaal sae eoedoucin 4.180 3.017 72.16 
IAN GLB RC yore wie receg dediacrreisre fannie sinh ent aeeel 4.180 3.165 75.69 
Average of [II and IV............... 4.168 3.079 73.84 
Wueat Guuten.—Seven experiments upon commercial wheat 
gluten are reported. three by Kithn and four by Kellner. The 
chemical composition of the dry matter of the three samples of 
gluten employed is shown in the first table on the next page. 
In Kiihn’s experiments the gluten caused a marked increase in 
the apparent digestibility of the basal ration, which by our method 
of computation augments the apparent metabolizable energy of 
the gluten, so that in one case it amounts to over 101 per cent. of 
the gross energy. The correction for organic matter is also rela- 
