376 BOARD OF AGIUCULTURE. 



the time of milking, the food, and undoubtedly the breed, for 

 upon examining the milk of widely diflerent species we find 

 constant differences. These differences are transmitted by 

 mheritance, for we cannot imagine a porpoise producing 

 cow's milk, or a cow yieldhig milk like that from the por- 

 poise. There is reason, then, in believing that each breed 

 produces a milk which differs in its percentage or other 

 arraufjements from the milk of other breeds. 



Milk is one of the products of the animal body which 

 possesses a form. It is composed of myriads of minute 

 globules of mixed fats, Inclosed each in an enveloping sub- 

 stance, which not only preserves the form, but protects the 

 contents from the act" on of ether. These globules tloat at 

 will in a colorless fluid composed of sugar of milk, caseine, 

 etc., in solution. Those globules, by their structure, give to 

 the combined fluid a physical quality, as distinct from chemical 

 quality. 



As these globules possess form, and undoubtedly have at 

 one time been a portion of the animal structure, it would be 

 expected a priori that they would differ somewhat in various 

 breeds, or, expressed otherwise, be subject to the observed 

 laws of inheritance. As the shapes of animals have been 

 modified to suit human needs or fancy, through the taking 

 advantage of those laws controlling form, we should likewise 

 expect that these globules, either knowingly or unwittingly, 

 would participate in changes, and would bear a relation to the 

 wants or requirements of the bi'eeder. 



It is in fact through the study of inheritance and a fixed 

 belief in its universality as a law, and in a firm belief in the 

 doctrine of causation, that I have been led to the investigation 

 whose results I am about to give. As I felt conscious that no 

 treatment or system of treatment of animals could fail to pro- 

 duce some lasting effects on their structure, and as changes 

 in form arc more clearly expressed than other changes more 

 involved, such as character and function, I was led to con- 

 sider milk in its morphological aspects, and first seeking 

 changed forms, to next attempt the following of such changes 

 to their logical conclusions, being careful to test each step by 

 careful experiment. 



My opportunities have been limited to three breeds, the 



