Dex-Info now has some of the early Dexter cow entries from the 1890 Kerry & Dexter Herdbook which includes Lily II, described as white, with very little red. This brings to mind the following abstract regarding white in Jersey cattle from 2000:
A possible dominant white gene in Jersey cattle
Chris A. Morris (a) and D. Phillip Sponenberg (b)
'A white heifer ("Snow") was born in 1991 from coloured registered Jersey parents. She produced six calves sired by coloured Jersey bulls: three white bull calves, two white heifer calves, and one coloured bull calf. One of the white bull calves was mated with 40 Hereford Friesian yearling heifers (white face, predominantly black body with some white patches). The 38 resulting calves included 16 white and 22 coloured calves. Twelve of the 16 white calves were heifers and four were bulls. Red or black spotting was recorded on some white calves. The results are consistent with an autosomal dominant mutant causing the white phenotype. The mutation appears to have arisen spontaneously in Snow, then passing to her white progeny and white grand-progeny. The white individuals varied from entirely white in a few cases, to most having some residual small areas of red or black pigmentation in patterns not typical of other reported white spotting patterns of cattle.'
(a) AgResearch, Ruakura Agricultural Research Centre, Private Bag 3123, Hamilton, New Zealand
(b) Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA