+---+----------------------+---------------+------------------+ | | Mother. | Father. |Comb in offspring.| |Pen+---------+-----+------+--------+------+---+---+----+-----+ |No.| | |P. ct.| | | | | | | | | No. |Comb.|split.| No. |Comb. | I | Y | oo | Abs.| +---+---------+-----+------+--------+------+---+---+----+-----+ |704| { 65 F1| Y | 50 | 1420 F2|Absent|.. | 10| 6 | 8 | | | {1061 F2| Y | 50 | 1420 F2| Do. |.. | 4| .. | 1 | | | | | | | | | | | | |819| { 57 F1| Y | 50 | 1420 F2| Do. |.. | 8| 6 | 5 | | | { 65 F1| Y | 60 | 1420 F2| Do. |.. | 1| .. | 1 | | +---+---+----+-----+ | Total | 0 | 23| 12 | 15 | +------------------------------------------+---+---+----+-----+ Finally, we must consider the result of mating a bird without papillæ (No. 1420, pen 704) with a median-combed hen (480). When this typical single-combed hen was used the 49 progeny were all of the Y type.[2] This proves that the combless type behaves only as an extreme of the non-median type. [2] One is reported as having a I comb; probably the limiting condition, again. When Y-combed hens were used with the combless cock the offspring had Y comb and non-median-comb in nearly equal numbers, 23:27 (table 8), but the latter included an unusually large proportion of combless fowl (15 in 27). When a combless hen (No. 4257) was used, 9 of the offspring had oo comb and 2 no comb; not a greater proportion of combless birds than in the no-comb×Y-combed cross. All of these facts indicate that "comblessness" is not entire absence of the comb factors, but a minimum case of the oo or paired comb. This result is opposed to the second hypothesis. The statistics of all matings between I, Y, and no comb on the one side and no comb on the other thus speak unanimously for the conclusion that in these matings we are not dealing with 2 pairs of allelomorphs, but with a single comb and its absence (third hypothesis) or with a case of particulate inheritance (first hypothesis). Moreover, it must be said that the split comb is obtained also when the Polish-Houdan comb is crossed with a pea comb or a rose comb; and the pea and rose combs can not be said to have "lateral comb absent," as required by the second hypothesis. Consequently the second hypothesis is definitely excluded.