156 STORRS AGRICULTURAL EXPERIMENT STATION 
parts consisted of fat in Holstein milk; 32.6 parts in Ayrshire 
mill; 34.8 in Guernsey milk and 37-0 parts in Jersey milk. 
The milk sugar ranged from 38.3 parts in Holstein milk to 
31.4 in Jersey milk. The ash ranged from 6.5% in Holstein 
milk to 5.5% of the total solids in Jersey milk. 
The casein constituted about one-fourth of the total solids 
in the milk of each breed. 
The total solids containing the largest amount of fat, con- 
tain proportionally less of milk sugar and ash. 
