INTRODUCTORY REMARKS. 7 



which have succeeded in defeating the greatest number of com- 

 petitors in that country, which is to be the seat of the competition 

 proposed to be carried on. The shape is, of course, tangible and 

 open to the eye; but the nature of what is called blood is of 

 a deeper character. Now, what is usually meant by ( blood ' ? 

 Mr. Thacker, who has done so much to explain and improve 

 the art of breeding the greyhound, was of opinion that there was 

 really a difference in the shape of the globules of the blood of a 

 high and low-bred greyhound ; but this theory is now known to 

 be fallacious. The microscope will measure the most minute 

 difference in size or shape, but still it fails to discover any such 

 deviation ; and no test, except perhaps the nose, could detect any 

 difference between the blood of the ( Flying Dutchman ' and 

 that of a cart-horse, or between the blood of a ' Mocking Bird ' 

 and that even of a sheep dog or lurcher. In the high-bred horse, 

 as well as in the high-bred dog, the skin is thin and delicate, and 

 the superficial veins are more readily seen ; but these vessels are 

 also really more numerous and capable of containing more blood ; 

 so that during the very severe struggles of a long- con tinned gallop 

 the heart and lungs are relieved from the overwhelming quantity 

 of fluid, which would otherwise be dangerous to the safety of the 

 animal. Hence the blood has been taken as a test of high 

 breeding, and has been supposed to differ in the form and com- 

 position of its globules, whilst the fact is, that the difference 

 really lies in the vessels which contain it. But the chief dis- 

 tinction between the high-bred animal and his inferior consists 

 in the brain and nervous svstem. It is true that we know little 



