MENDELISM IN DOMESTIC ANIMALS 467 
Taste LXI.—Tur Transmission or Coat Coror in Horsrs tn VArnious Typns or 
Marines 
Mating Chestnut | Black | Brown | Bay | Gray | Roan 
Chestnut X Chestnut.......... 14,115 10 1 5 
Chestnut X Black............. 111 83 20 124 
Chestnut X Brown............ 60 32 31 130 
Chestnut X Bay.............. 597 56 49 764 
BlackexeBlackstvac sss seer 11 295 15 5 
Black >< Brown... 4.0.2: 00.08 14 198 219 115 
Black D@ Bayne aairovcsheeen. 123 295 261 634 
Brown X Brown.............. 13 64 334 157 
Bay X Brown.........4.....«. 177 132 817 1,449 
Bayo bay ese an en eat 107 | 300 | 2,831 
Roan X Chestnut............. | 9 3 | 2 9 1 14 
Roan <eBlackesa.sssccn S05 sa | 1 11 | 3 1 0 1'5 
Roamexe Brow see nas 1 5 16 18 1 28 
LiKoyeyok Dg ISN Aird con eo ere ae 9 5 13 39 1 50 
Dito UCN anaes Ge eon Mona ae 7 3 5 7 
IRvoH NY, Oe Mop hla nan nntnaeomane.5|| qo Hoe 3 ee 3 2, 9 
Gray X not Gray............. Not gray 528 439 
Gravee Grayiee aac ace Not gray 18 47 
| 
Wentworth, Cole found in tabulating the offspring of gray mares re- 
corded in the Clydesdale studbook that exactly 50 per cent. were gray 
and 50 per cent. not gray, which is in strict conformance to expectation. 
Roan is a coat color characterized by a slight sprinkling of white hairs 
in a pigmented coat. The roan color is even less popular in breeds than 
gray, and it occurs to any great extent only in Belgian draft horses. The 
roan factor, R, is a dominant pattern factor independent of any of the 
color factors. It is, therefore, possible to have gray roans, red roans, 
blue roans, and chestnut roans according as the pigmented coat color is 
gray, bay, black, or chestnut, respectively. Gray roans are not dis- 
tinguishable from ordinary gray of course, except at birth, so that this 
class is merely a genetic one not recognized in practical breeding opera- 
tions. At birth gray foals are black, whereas gray-roans are black 
with interspersed white hairs. The data of Table LXI indicate plainly 
enough that roan is a dominant color, but some reports of individual 
animals are even more interesting. Thus J. Wilson reports that a red- 
roan Belgian stallion standing for service in Story County, Iowa, was 
bred -to all classes of mares, but all of the 256 foals he sired were 
red-roan like himself. Another red-roan stallion sired 254 colts of which 
230 were red-roan and the remaining 24 blue-roan. These two stallions 
must have been homozygous for the roan factor, and their breeding re- 
cords establish clearly the dominance of the roan coat color pattern. 
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