THE NETWORK OF VEINS. 89 



traced; and hence, to judge of its size when the cow is 

 dry, or nearly so, this vein may be pressed near its end, 

 or at its entrance into the body, when it will immedi- 

 ately fill up to its full size. This vein does not carry 

 the milk to the udder, as some suppose, but is the chan- 

 nel by which the blood returns ; and its contents ccnsist 

 of the refuse of the secretion, or what has not been 

 taken up in forming milk. There are, also, veins in the 

 udder, and the perineum, or the space above the udder, 

 and between that and the buttocks, which it is of spe- 

 cial importance to observe. These veins should be 

 largely developed, and irregular or knotted, especially 

 those of the udder. They may be seen in Figs. 29, 

 30, 31, &c. They are largest in great milkers. 



The knotted veins of the perineum, extending from 

 above downwards in a winding line, are not readily 

 seen in young heifers, and are very difficult to find in 

 poor cows, or cows of only a medium quality. They 

 are easily found in very good milkers, and, if not 

 at first apparent, they are made so by pressing upon 

 them at the base of the perineum, when they swell up, 

 and send the blood back towards the vulva. They form 

 a kind of thick network under the skin of the perineum, 

 raising it up somewhat, in some cases near the vulva, 

 in others lower down and nearer to the udder. It is 

 important to look for these veins, as they often form a 

 very important guide, and by some they would be con- 

 sidered as furnishing the surest indications of the milk- 

 ing qualities of the cow. Their full development almost 

 always indicates an abundant secretion of milk; but 

 they are far better developed after the cow has had two 

 or three calves, when two or three years' milking has 

 given full activity to the milky glands, and attracted a 

 large flow of blood. The larger and more prominent 

 these veins, the better. It is needless to say that in 

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