90 ZEBRAS, HORSES, AND HYBRIDS 



practically complete reversion also as to form. ' In 

 its measurements it is relatively almost identical with 

 a typical Shetland blue-rock.' The tail feathers are 

 twelve in number, and show but the faintest indica- 

 tions of any colour-inheritance from their immediate 

 parents. An additional point of interest is that in 

 disposition this bird seems wilder and more shy 

 than the domesticated breeds usually are. It is 

 vigorous and hardy, and is much admired by the 

 fanciers. 



Another bird whose wild ancestor is known with 

 a high degree of certainty is the barn-door fowl. It 

 has sprung from the jungle fowl, Gallus bankiva, and 

 less remotely from the game fowl. Hence, if fowls of 

 different breeds are crossed, the offspring, should 

 reversion occur, ought to resemble either the jungle 

 fowl or their less remote ancestors, the game fowl. 

 A dark red-breasted bantam was crossed with an 

 Indian game Dorking; of the nine chickens which 

 resulted, six resembled Dorkings, and three in both 

 form and colour resembled game birds. Two of the 

 three grew up, and the only visible trace of their 

 parentage was a double comb inherited from their 

 cross-bred father. Here again the reversion does not 

 stop at the colour and form, but extends to disposi- 

 tion ; the birds are very shy, and fly about like wild 

 birds. The above are but two instances out of many 

 which might be quoted from the Penycuik experi- 

 ments ; they are, however, unusually clear cases, and 

 should do something to restore confidence amongst 

 recent doubters of reversion. 



An animal is said to be prepotent when it strongly 

 impresses its own peculiarities of form, colour, tem- 

 perament, etc., on its offspring. In the above-men- 

 tioned experiment with pigeons the owl had been 

 prepotent over the archangel in the mother of the 

 offspring which showed such marked reversion. 



