184 DAVENPORT 



the offspring show no blend, they are either four-toed or five- 

 toed, and neither character dominates. If the extra toe is well 

 developed in the parents a large percentage of the offspring 

 have an extra toe ; if the extra toe is poorly developed in 

 the parents a small percentage of the offspring have an extra 

 toe. In this case we have a unit character — extra toe — but no 

 dominance or recessiveness and no evidence of pure germ-cells. 

 The result seems to depend on the relative potency of the four- 

 toed and the five-toed tendency. 



Third, we find that one of the two opposed unit characters 

 may be dominant in certain individuals and their offspring — 

 forming a dominant strain — the same character may be reces- 

 sive in other individuals or strains. Thus when high nostril 

 and low are crossed, the offspring have a low nostril, but in 

 one case out of a hundred an individual gamete carrying high 

 nostril prevailed over the gamete carrying low nostril and the 

 offspring had a high nostril. Again I bred a single comb to a 

 rose comb (rose being dominant) and, in the second hybrid 

 generation, obtained some extracted single-combed birds. These 

 inbred gave a hundred single combs and one rose comb ; the 

 ordinarily impotent rose comb determinant of the extracted singles 

 here overpowered its mate. 



But the most striking illustration of the potency of a strain 

 appeared last summer. Two years ago I mated a tailless Game 

 cock. No. 117, to some tailed white Leghorns and got 100 per 

 cent, tailed birds. No. 117 is a bird imported from England; 

 it was exhibited at the Louisiana Purchase Exposition, St. Louis, 

 1904, and took a prize. Last summer I mated together these 

 tailed hybrids, expecting to get 25 per cent, tailless birds ; of 

 about 100 offspring none was tailless. I also crossed some of 

 the tailed hybrids with their father — No. 117 — expecting to get 

 50 per cent, tailless. Of 88 offspring none was tailless. Alto- 

 gether, out of 200 o^spring of this tailless cock, where I ex- 

 pected 90 per cent, tailless birds, I got not one. On the other 

 hand, using some of the same hens with another cock (the son 

 of No. 117), from 50 offspring, where I expected 25 tailless, I 

 got 24 tailless. In No. 117, although tailless, the tailed tendency 

 strongly dominates over taillessness, so that not in the first nor 



