Animal coloration : an account of the principal facts and theories relating to the colours and markings of animals / by Frank E. Beddard.

  • Beddard Frank E. (Frank Evers), 1858-1925.
Date:
1892
Catalogue details

Licence: Public Domain Mark

Credit: Animal coloration : an account of the principal facts and theories relating to the colours and markings of animals / by Frank E. Beddard. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    Scotlaud ; occasionally the change occurs in the Midlands, and white stoats have been recorded from Cornwall, and from Gloucestershire even during a mild winter. The accompany- ing woodcuts (figs. 1, 2) illustrate the winter dress of some of the animals referred to in the text; the Arctic fox (fig. 1) is shown both in summer and winter dress. The actual mode of the change in the colour of the fur has been carefully worked out by Mr. AVelch* for Lepus americanus. The change in the summer coat is accomijlished without the shedding of hair ; but there is a new growth of white hair. Naturally the winter coat is thicker than the summer coat. Besides the increase in the thickness of the fur produced by the growth of new hairs, the coloured hairs change their colour and become blanched. This blanching usually commences- at the tip, and does not always involve the whole of the shaft. The entire change occupies three months ; it begins about the first week in October, and is completed by the last week of December. The change is more rapid in other animals. In a lemmino- Sir John Eoss found the change to take place in a week. It is thought that it is the change of temperature which produces the change in the hair ; but it would be very im- portant to ascertain whether this is really the case, and, if so, what are the hmits of cold within which the change will or will not occur. The experiment of Sir John Eoss upon the lemming ajDpears almost to settle the point. The animal was kept in the cabin through the winter, and first exposed ou deck on February 1st; on the next day it had several white .patches, and, as already stated, became white in a week, but the creature died a few days afterwards. On the other hand, the whitening of • Proc. Zool. Soc, 18G9.