94 BOARD OF AGRICULTUEE. 



be discovered ; are there external marks or signs to guide us 

 in the selection ? . Cei-taiuly ; signs that can be easily detected 

 in the form of the body, in the shape of the limbs, in the hair 

 and skin, and in the movements of the animal. A little 

 experience and discrimination will readily jjut one on the right 

 track. 



Closely identified with this pai-t of the subject, there is a 

 feature of great importance, especially where labor is required, 

 viz. : hardness, toughness, power of endurance, &c. While 

 this element is gi-eatly enhanced by habits of exercise and 

 exposure, it depends more upon quality of structure coml^ined 

 with a well-balanced organization. These conditions must be 

 supplied in a great measure by inheritance, and it will be 

 seen by careful analysis and comparison, that the nearer we 

 approximate in organization the true law of propagation, the 

 more of these qualities shall we obtain. 



Connected with this quality of structure, there is one point 

 worthy of consideration ; that is, that there are bounds or 

 limits to it, — not merely upon the ground of utility, but of 

 existence. If both parents possess this kind of organization 

 in a higlj degree, it is transmitted in an intensified form, and 

 the farther it is carried, experience shows the stock will 

 gradually run out. Thus, as we approach the two extremes, 

 fineness and coarseness of organization, we shall find that 

 animal life will decrease more and more. Thus from these 

 two stand-points we derive strong presumptive evidence to 

 show that there must be a great general law of propagation 

 somewhere between these two extremes. 



DISEASE INHEEITED. 



One of the most important points connected with hereditary 

 influence is the matter of disease. No law in nature is more 

 firmly established than that disease, or rather the morbid con- 

 ditions that generate it, are transmitted. This may exist in 

 the very structure itself, or in the fundamental derangement 

 of some particular organs. And it is a well-known fact that 

 certain kinds of disease are more liable to be transmitted than 

 others. The fact also is well established that animals, in pro- 

 portion as they become domesticated, become thus more liable 

 to disease ; and, at the same time, their complaints assume 



