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THE AMERICAN NATURALIST [Vol. XLVIIT 



practically so ; second, that in which there is a greater or 

 less tendency for the primary patches to be much broken 

 up into small islands (as in Fig. 36) by secondary breaks, 

 though the main areas are still distinguishable. I take 

 this second or fragmental type to be a different phenom- 

 enon from the diffuse or dappled condition seen in the 

 coach dog or the dappled-gray horse. 



In the cow, the ear patches as usual pigment each its 

 proper side of the head to a short distance behind the 



ears. The point of separation between ear patches and 

 neck patches is indicated by a small break back of the 

 skull in Fig. 38, while the posterior extent is shown by 

 the two ear patches in Fig. 42. These patches usually 



