They form into herds of different sizes from ten to a hundred according as their fears or accident induce them to unite or separate.
The females being at this time more lean and active usually lead the van.
The haunches of the males are now covered to the depth of two inches or more with fat which is beginning to get red and high flavoured and is considered a sure indication of the commencement of the rutting season.
Their horns, which in the middle of August were yet tender, have now attained their proper size and are beginning to lose their hairy covering which hangs from them in ragged filaments.

The horns of the reindeer vary not only with its sex and age but are otherwise so uncertain in their growth that they are never alike in any two individuals.

The old males shed theirs about the end of December; the females retain them until the disappearance of the snow enables them to frequent the barren grounds which may be stated to be about the middle or end of May, soon after which period they proceed towards the sea-coast and drop their young.

The young males lose their horns about the same time with the females or a little earlier, some of them as early as April.

The hair of the reindeer falls in July and is succeeded by a short thick coat of mingled clove, deep reddish and yellowish browns; the belly and under parts of the neck, etc., remaining white.