GUENON EXPLAINED. 95 



the up-growing hair, make the parts covered by it very 

 perceptible. 



As the hair of the milk-mirror has not the same direc- 

 tion as the hair which surrounds it, it may often be dis- 

 tinguished by a difference in the shade reflected by it. 

 It is then sufficient to place it properly to the light to 

 see the difference in shade, and to make out the part 

 covered by the upward-growing hair. Most frequently, 

 however, the hair of the milk-mirror is thin and fine, 

 and the color of the skin can easily be seen. If we 

 trust alone to the eye, we shall often be deceived. 

 Thus, in Figs. 52 and 53, the shaded part, which 

 extends from the vulva to the mirror E, represents a 

 strip of hair of a brownish tint, which covered the peri- 

 neum, and which might easily have been taken for a 

 part of the milk-mirror. 



In some countries cattle-dealers shave the back part 

 of the cows. Just after this operation the mirrors can 

 neither be seen nor felt ; but this inconvenience ceases 

 in a few days. It may be added that the shaving, 

 designed, as the dealers say, to beautify the cow, is 

 generally intended simply to destroy the milk-mirror, 

 and to deprive buyers of one means of judging of the 

 milking qualities of the cows. 



It is not necessary to add that the cows most care- 

 fully shaven are those which are badly marked, and that 

 it is prudent to take it for granted that cows so shorn 

 are bad milkers. 



Milk-mirrors vary in position, extent, and the figure 

 they represent. They may be divided, according to 

 their position, into mirrors or escutcheons, properly so 

 called, or into lower and upper tufts, or escutcheons. The 

 latter are very small in comparison with the former, and 

 are situated in close proximity to the vulva, as seen at S 

 in Figs. 38, 39, 40, etc. They are very common on cows 



