326 
recommended. According to Temesvary (63) beer increases the 
amount of milk fat. Morgen, Beger, and Fingerling (64) have also 
investigated the influence of fat and other substances on milk produc- 
tion when fed in connection with a scanty basal meal. They have 
observed an increase in the yield of milk and an increase in the per- 
centage of fat amounting to 0.14 per cent when such quantities of fat 
were added to the food. The addition of large quantities of fat to the 
food caused a further increase in the yield of milk, but was found to 
vary in its effect on milk-fat production, sometimes causing an in- 
crease, sometimes a decrease. Caspari (65) has shown that iodized 
fats appear in the milk even though the food be poor in fats and 
rich in carbohydrates. He therefore concludes that some of the 
fat of milk comes from the fat of the food. Later (66) he showed 
that when iodocasein and iodoalbumin are fed to an animal no traces 
of iodized fats appear in the milk. On the other hand there are 
those who hold that the addition of fat to food does not increase the 
quantity of fat in milk and that there is no direct migration at least 
of the fat of the food to the milk. Such a conclusion was arrived at 
by Einecke (67) from his experiments with goats. With liberal com- 
prehensive rations the yield of milk and fat depends, according to 
this observer, on the individuality of the animal. The milk from 
cows grazing off the poor, dried-up grass on the plateau of Setif, in 
Algeria, has been compared by Malmejac (68) with that of cows fed 
on rich forage with the following results : 
Poor dry grass. 
Rich forage. 
Total solids 
11. 62 to 14. 25 
3. 33 to 3.50 
3. 13 to 4.46 
4.53 to 5.64 
0.60 to 0.90 
13. 76 to 14. 90 
4. 05 to 4.90 
3. 33 to 4.54 
4. 47 to 5. 55 
0.82 to 0.93 
Fat 
Lactose 
Proteids 
Ash 
Except for the proteids, the differences in composition are obviously 
in favor of the milk produced on the richer diet. Woll (69) ob- 
served that as a food for milch cows silage increases the yield of milk 
and butter 3 per cent over that produced with maize fodder when the 
area of land required to produce the two foods is taken into account. 
Some studies have also been made of the effects of certain definite 
nitrogen and phosphorus compounds on the production of milk and 
milk fat. Morgen. Berger, and Fingerling (60) have investigated the 
effect of adding lecithin to food. This substance seemed to increase 
the yield of milk and also the live weight of the animal. It was 
found, however, to be favorable to the production of milk fat only 
when it was fed in conjunction with other foods deficient in fat. 
Pfeiffer, Einecke, and Schneider (70) have shown that asparagin 
