Numerous observations have been made upon the progeny of parents belonging to hybrid generations beyond the first. Owing to the extreme imperfection of dominance it is rarely possible to say with certainty from inspection whether a given bird has germ-cells dominant or recessive, or both, with reference to booting; only breeding enables us to make a decision. There is an exception, however, in the case of pure extracted recessives. They are distinguished by heavy booting and produce only booted offspring. I propose to give, in detail, the matings of these later generations and their progeny, the families being arranged in decreasing order of average grade of booting (table 38). TABLE 38.--_Distribution of boot-grades in offspring of parents one or both of which belong to a hybrid generation beyond the first._ B = Brahma; C = Cochin; G = Game; L = Leghorn; M = Minorca; S = Silkie; Sp = Spanish; T = Tosa; WL = White Leghorn +------+---+------------------------+------------------------+-------+-------------------------------------+ |Serial|Pen| Mother. | Father. |Mating.| Boot-grade in offspring. | | No. |No.+----+-----+---------+---+----+-----+---------+---+ +--+--+--+--+--+--+--+--+--+--+--+----+ | | | No.| Gen.| Races. |Gr.| No.| Gen.| Races. |Gr.| | 0| 1| 2| 3| 4| 5| 6| 7| 8| 9|10| Av.| +------+---+----+-----+---------+---+----+-----+---------+---+-------+--+--+--+--+--+--+--+--+--+--+--+----+ | 1 |814| 354| F1 |B × T | 7|3975| F2 |B × T | 9 |R × R |..|..|..|..|..|..|..|..|..|10|15|9.6 | | 2 |801| 181| F1 | Do. | 4|5399| F2 |M × B | 8 | Do. |..|..|..|..|..|..|..|..|..| 1| 1|9.5 | | 3 |814| 300| F1 | Do. | 5|3975| F2 |B × T | 9 | Do. |..|..|..|..|..|..|..|..| 1| 3| 4|9.4 | | 4 |801|4569| F2 | Do. | 6|4562| F2 | Do. | 7 | Do. |..|..|..|..|..|..|..|..| 1| 1| 2|9.3 | | 5 |814|5523| F2 | Do. | 9|3975| F2 | Do. | 9 | Do. |..|..|..|..|..| 1|..|..| 3| 4| 9|9.1 | | 6 |814|4560| F2 | Do. | 8|3975| F2 | Do. | 9 | Do. |..|..|..|..|..| 1| 1| 1|..| 2| 7|8.8 | | 7 |814| 190| F1 | Do. | 2|3975| F2 | Do. | 9 | Do. |..|..|..|..|..|..| 1| 1| 1| 1| 4|8.8 | | 8 |806|4325| F3 |M × B | 7|5257| F3 |M × B | 9 | Do. |..|..|..|..|..|..| 1| 1| 2| 2| 3|8.6 | | 9 |806|5913| F3 | Do. | 7|5257| F3 | Do. | 9 | Do. |..|..|..|..| 1|..|..| 1| 4| 2| 3|8.3 | | 10 |732|1235| F2 | Do. | 8|2732| F2 | Do. | 6 | Do. |..|..|..|..|..|..| 1| 2| 4| 3|..|7.9 | | 11 |806|4052| F3 | Do. | 5|5257| F3 | Do. | 5 | Do. |..|..|..|..| 1| 1|..| 3|..| 6| 1|7.8 | | 12 |776|1132| F2 |C × WL | 3|2732| P. |C | 8 |DR × R |..|..|..| 1| 1| 1| 1| 3| 6| 8|..|7.6 | | 13 |801|6869| F1.5|B × F1 | 6|4562| F2 |M × B | 7 |R × R |..|..|..|..|..| 1| 1| 2| 1| 1| 1|7.4 |