In races having a large single comb this is usually erect in the male, but in the female lops over to the right or left side of the head. This lop is determined before hatching; indeed, in the male it may be ascertainable only in the embryo or in the recently hatched chick. The position of the comb is permanent throughout the life of the pullet and hen and, if pressed to the opposite side, it quickly returns to its original position. At one time I entertained the hypothesis that its position was determined by the pressure of the foot against the head while the chick was still within the shell; but after finding the comb lying both to the right and to the left when in contact with the foot I abandoned this hypothesis as untenable. It seemed possible that this position is hereditary, and so data were collected to test this hypothesis. It is not always easy to decide definitely, even for the female, as to the direction of the lop; for the anterior part of the comb may lop to the right, the posterior part to the left, or _vice versa_. In that case one selects the larger or better defined lopping portion to designate as _the_ lop. This is usually the posterior portion of the comb. However, such doubtful cases may be omitted from consideration here, as there are plenty of examples of well-defined lop on both sides of the head. TABLE 56. +------------------------------------------------------+ | Both parents with right lop. | +----------+-----------+-----------+-------------------+ | | | | Offspring. | | Pen No. | No. of | No. of +---------+---------+ | | mother. | father. | Right. | Left. | +----------+-----------+-----------+---------+---------+ | | | | | | | 817 | 6188 | 3900 | 7 | 8 | | 817 | 6406 | 3900 | 12 | 17 | | 831 | 1011 | 4213 | 7 | 16 | | 831 | 3040 | 4213 | 13 | 10 | | 831 | 4219 | 4213 | 4 | 21 | | 831 | 6602 | 4213 | 6 | 15 | | 833 | 1310 | 4222 | 4 | 7 | | 833 | 4361 | 4222 | 6 | 4 | | 833 | 7519 | 4222 | 2 | 4 | | 904 | 4714 | 7870 | 6 | 7 | | | | +---------+---------+ | | | | 67 | 109 | +----------+-----------+-----------+---------+---------+ | Both parents with left lop. | +----------+-----------+-----------+---------+---------+ | | | | | | | 841 | 3867 | 3890 | 3 | 9 | | 841 | 4663 | 3890 | 9 | 7 |