28 Cattle Problems. 



Mark, thus calling ihe attention of others to the subject, 

 and in pointing out the coincidence of yield, in nearly all 

 good cows, with the size of the Yield Mark. 



Having described the process by which it is formed, and 

 shown the nature of force that establishes the Yield Mark, 

 demonstrating its relation to yield, as an effect thereof, in 

 special chapters on that subject, we pass on to consider a 

 few of the various forms of Yield Mark shown in Guenon's 

 illustrations, for the convenience of readers who have read 

 Guenon's treatise, who may find the subject, in its various 

 bearings, further explained in Chap. Y., on variations in 

 form of Yield Mark, and illustrated in Yield Marks and 

 other figures of this work. 



In referring to Guenon's illustrations we prefer to confine 

 our remarks to the sccondh<t%t cows or orders in the classes 

 of his cuts. We include two new classes shown in a chart * 

 in which the new classes of Yield Marks are introduced, 

 one of which, the left flanders, or class II., we shall now 

 briefly consider, together with class 6, in Guenon's work 

 marked VIII. in the Pennsylvania chart. 



The peculiar fact about these two classes is, that in every 

 instance in which the Yield Mark is larger on one side 

 than on the other, the larger part is on the left side of the 

 twist; and in every instance in which it curves or diver- 

 ges from a perpendicular direction, the divergence, bend, 

 or curving is on the left side of the twist, and when the 

 mark of weight-strain extends higher on one side than on 

 the other, its extension is on the left side, even as high as 

 the vulva, or rcnot of the tail in several of Guenon's figures. 

 The general form of the udder in these figures is correct ; 

 but the sharp points in the Yield Marks we have rarely 

 met with. The Yield Mark being due to weight-strain, 

 should be as large on one side as the other, the yield 



♦Distriliiitfil with tlu' Annual Ri'poi'l of Pcnnsylvaniil Board of \gricnltnr 

 for 18T8. 



