434 On the Inheritance of Coat-Colour in Cattle 
blue-grey. He has at present a black lieifer from this cross and has personally 
known instances of the dark blue-greys. Mr Richardson's experience is the same 
as Mr Irving's, i.e. black and blae-grey. Mr Tinniswood's experience is that the 
offspring take black, but occasionally, especially if from light blue-grey cows, the 
black is accompanied by white markings. Mr Hodgson finds the coat-colour not 
very certain, generally black ; but from a light blue-grey cow he has had blue- 
greys and roans ; from a darh blue-grey cow, generally black with only an occa- 
sional roan. This is interesting because we have seen that the light blue-grey 
results from the purity of the Galloway cow and the white parentage of the short- 
horn bull. It would thus appear that the grandparental ancestry influences the 
nature of the cross {BW) x {BE), through the character of the {BW) itself. 
Messrs Hyslop have had still more varied results, namely, dark blue-grey, some 
"grizzled" (red and white hairs), black, and white with black nose and ears. In 
other words if white with black nose and ears be taken to represent the (IFIF) 
arising from {WW) x {BW), it cannot represent the {BW) in {BB) x {BW). 
We now turn to the last problem: what does {BW) x {BW) give? Messrs 
Tinniswood and de Vere Irving have never tried the cross. In fact it is clearly 
not one that blue-grey cattle breeders are likely to make*. Mr Hodgson has had 
no personal experience of this cross, but has seen instances in which a blue-grey 
bull being used on blue-grey cows, blue-grey and roan offspring resulted. Mr 
Richardson has known instances in which this cross being made the offspring were 
nearly all blue-grey, but the following season with the same cows and bull, red, 
roan, white, black, with only a few blue-grey calves appeared. Messrs Hyslop 
state that the cross gives blue-grey, black, red, " grizzled " (red with white hairs) 
and an occasional white. The}' know no breeder, however, who makes at present 
this cross although it used to be ft)llowed. So far as this experience goes therefore 
{BW)x {BW) appears to give {BW), {BB) and possibly ( If IF), although it is not 
white with black markinL;s, such as occurs in the {BW) x (TFTT) axid.{BW) x {BB) 
crosses. But on the other hand red hair has appeared when the original pure 
bred Galloway and sliorthorn did not patently contain this colour. 
To sum up, we tnay conclude, we think : 
{a) That when pure black and pure white parents of races which breed nearly 
true are crossed, the hybrids are not homogeneous, there is a certain amount of 
segregation even in this generation, and colour may appear which was latent in 
the parents. It seems to us a difference in words only, whether we attribute this 
appearance to a latent determinant, or say that it is reversion to an ancestor. 
The pedigree is, in fact, the only a jiviori guide the breeder has to the possibility 
* Mr Tinniswood breeds about 100 blue-grey calves a year. As he remarks, it is possible to get 
blue-greys from crossing a blue-grey cow with either a Galloway or shorthorn bull, but the colour "very 
seldom occurs." Hence the breeder naturally turns to the white shorthorn and Galloway first cross. 
Mr Tinniswood has used both crosses, generally the shorthorn bull, but also the pure shorthorn white 
cow and the Galloway bull, a cross he has never known to give red or roan. He has known red or 
roan from the reciprocal cross, and attributes it to want of pedigree in the Galloway cow. 
