378 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ III, IV.

Where there is great divergency in fineness between parental types, little uniformi-
ty could be expected, but the use of rams of the long, lustre-wool type gave a very
uniform generation. (Full results of this work will be published later.)

                    INHERITANCE OF LENGTH OF WOOL-FIBRE.

Mean length of wool-fibre in all breeds except those with a very even staple is
difficult to determine. In breeds where the fleece has a typically pointed staple,
which includes all the long-wool, lustre-wool, mixed-wool, and many of the inter-
mediate types, the staple is composed of fibres of varying lengths, the tip being
formed by the longest fibres. In such a staple, when the fibres of which it is
composed are measured, it is found that typically they show a fairly normal
frequency-dispersion curve, with considerable variation between different staples.
When staple is considerably thicker at its base than at its tip, as in breeds which
have mixed wool, the frequency-dispersion curve is likely to be bimodal with a
tendency towards great irregularity, especially marked when measurements are
made during the course of active wool-growth. In the Down breeds and in wool
of the Merino types, where the staple is ' blocky' at the tip, mean fibre-length can be
more accurately determined, but care must be exercised in obtaining representative
samples.

In very general terms, wool-length in crosses is intermediate between the
parents'. Some authors have reported greater length to be mainly dominant to
shorter length, but, since other workers using the same breeds have failed to find
any evidence of dominance, it would appear that in the former cases there may
have been a failure to appreciate the differences in length between first year's
fleece and subsequent fleeces. Reference has already been made to this point.

Among the results recorded where the inheritance of wool-length was studied
in breeding experiments, the following are cited as typical examples. Thilo (1912)
found Leicester ♂ × Merino ♀♀ that the length of wool in the F₁ generation, was
intermediate between the parents'. Measurements recorded were; Leicester,
18 cm.; Merino, 6 cm.; F₁ 12 cm. Baur and Kronacher (1919) confirmed these
findings. Macalik (1924) reports intermediate length in crosses, whilst F. R.
Marshall (1916) during an examination of hundreds of Corriedales, found that none
had wool as short as the longest Merino, and although the length of wool in the
Lincoln was approached by some Corriedales, it was never attained. In subsequent
generation wool-length remains intermediate, and the typical Corriedale breed has
wool of intermediate length; at the same time it should be remembered that the
modern Corriedale has been continuously selected for just this intermediate length,
and it is difficult to get information of the number of culls which were made in
early generations because of irregular length of wool. Ewart (1919) found the F₁