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THE AMERICAN NATURALIST [Vol. XLV 



thing but red or roan calves — mutations excepted. In the 

 present light, the absence of white calves from red 

 parents, the absence of entire coat albinos, and the ab- 

 sence of theoretical type No. 3 are mutually corroborative 

 phenomena. The fact that white by white — Table I — pro- 

 duced a roan may mean nothing more than that the 

 mating was of type No. 43, in which 75 per cent, white and 

 25 per cent, roan offspring are expected. 



As to the spotted animals, they seem to be of the same 

 nature as the roans. Just as there are mulattos and 

 " spotted" negroes due, respectively, to fine and coarse 

 mosaics of the pigment granules, there are roan cattle, 

 which roan effect is due to a very close intermingling of 

 red and white hairs; and spotted cattle, due to a coarser 

 mosaic of the same, which coarser mosaic came from a 

 distinct inheritance source — doubtless the Dutch bulls of 

 eighteenth century importation, as previously stated. In 

 this paper, the spotted animals have thus far been treated 

 as roans; they have never been popular with breeders, 

 consequently, there are relatively few of them — the few 

 (three) Sittyton matings being typical. It is observed 

 from the table that when a mixed color animal is mated, 

 the mixed color offspring tend to be like the mixed color 

 parent — i. e., either largely roan or largely spotted, as the 

 case may be. 



TABLE VI 

 (Calculated from Table I) 

 Red by spotted gives 23.3 per cent, spotted and 12.7 per cent. roan. 

 Red by roan gives 4.4 per cent, spotted and 46.6 per cent. roan. 

 Roan by spotted gives 25.5 per cent, spotted and 45.3 per cent. roan. 



The persistence of spottedness in the offspring of 

 spotted parents is accounted for by the fact that the color 

 areas are definite in location and contour and, being inde- 

 pendently transmitted, the registering of fortuitously the 

 red or the white phases of the homologous areas of the 

 two spotted parents will generally produce spottedness in 

 offspring. A similar registering of roan and spotted 

 coats would make the spottedness less pronounced. 



There are all degrees of the roan condition, varying from 



