MASSACHUSETTS. 161 



in the ration. In connection with this project the effect of lactic 

 acid in the ration was also considered. 



The project on arsenicals and their injury was confined to the 

 i:)reparation by the chemical department of practically pure Paris 

 green with the amoimts and kinds of impurities actually known. 

 xVrsenate of lime was also prepared practically pure, and similar 

 work on arsenate of lead was taken up. The digger wasp was studied 

 during the year mainly from the standpoint of its economic im- 

 portance. 



The investigations on the relation of climate to the development of 

 crops in health and disease included the study of light, particularly 

 as related to greenhouse construction, the relation of moisture to 

 blight of lettuce and melons, and the relation of heat, light, and 

 moisture to wilt. Attention was further given to the development 

 of methods for determining the amounts of heat and light required 

 in crop production, and to malnutrition and overnutrition in relation 

 to disease. 



The study of Mendelism was continued with 18 varieties* of beans 

 variously crossed, in tracing principally the factor of color in the 

 flowers, the plant in general, and the seed coat, and of stringiness 

 in the pods. Similar studies were also made of the color in the leaf 

 and floAver of nasturtium, and biometrical work was carried on with 

 peas. The effect of variation in the apple, as due to climatic influ- 

 ences, was studied, and in this connection it was found that variation 

 in form, as due to climate and most often to proximity to bodies of 

 water, was very marked. 



Under the Hatch fund, the chemist studied the digestibility of 

 various samples of prize corn and found that no practical differences 

 existed. Determinations of the amount of dry matter in large leafy 

 varieties of corn and in smaller-leaved sorts indicated that the 

 ixmount of dry matter in the leaves and ears of both types is about 

 the same and that the larger varieties show an increased yield in 

 stalk and in the amount of water. The digestibility of alfalfa and 

 clover at different cuttings was studied, and feeding experiments 

 were made with dried-molasses beet pulp and ordinary beet pulp 

 in comparison with corn meal for cows. Work was continued on 

 the protein requirement for dairy cows, the quantities used in the 

 test ranging from 1^ to 3 pounds of protein per day. 



Cooperative experiments were carried on with this department and 

 with two tobacco growers in the State for the purpose of comparing 

 one of the new varieties of Habana with the ordinary varieties, and 

 of priming with the usual practice of cutting the stalks and hanging 

 them up for the leaves to cure. A study was also made of the degree 

 of maturity for priming. Among other lines of work conducted by 

 91SG6°— 11 11 



