Once fairly hatched, the danger decreases; the young birds, while still quite small, show great readiness in concealing themselves. When disturbed they separate in all directions, crouch on the ground, squeeze between objects that seem to defy all passage, work their way through the cover, or, if they fancy that an eye is fixed on them, lie as motionless as stones. When so far grown as to be able to fly, they still prefer the shelter afforded by the cover; but if hard pressed the old cock usually rises first, with a cry which some compare to the quack of a Duck. The hen and young birds show no hurry in following his example, but take wing singly, and at unequal intervals--not like Partridges, which always rise in a covey. This is the period when they afford the easiest shot to the sportsman, who often puts them up almost beneath his feet, or under the very nose of his dogs. Later in the season a great change takes place, and this, it is said, whether the birds have been much harassed or not. Become cautious and wild, they no longer trust to concealment or swiftness of foot, but, discovering from a great distance the approach of danger, they rise most frequently out of shot, so that it requires skill and patience to get near them. A slight and early snow sometimes makes it more easy to approach them, at least for a few hours; but ordinarily, not even extreme cold, or a covering of snow a foot thick, appears to tame them at all. Under such circumstances, they collect in enormous 'packs', and betake themselves to some particular part of the moor from which the snow has been more or less drifted. These packs keep together during winter, and at the beginning of spring separate and pair, not, however, without some previous altercations; but these are soon over, and they lose much of their shyness, venturing close to the roads, and being little disturbed by the passage of the traveller.
_Winter plumage_--pure white, a black line from the angle of the beak through the eye; outer tail-feathers black; above the eyes a scarlet fringed membrane; bill and claws black; tarsi and toes thickly clothed with woolly feathers. _Female_--without the black line through the eyes. _Summer plumage_--wings, under tail-coverts, two middle tail-feathers, and legs white; outer tail-feathers black, some of them tipped with white; rest of plumage ash-brown, marked with black lines and dusky spots. Length fifteen inches. Eggs reddish yellow, spotted and speckled with deep reddish brown.