There are a large number of varieties, differing chiefly in the form and division of the pinnae; var.
Cambricum (originally found in Wales) has the pinnae themselves deeply cut into narrow segments; var.
Cristatum is a handsome variety with fronds forking at the apex and the tips of all the pinnae crested and curled.
Long, including the stalk; it is characterized by having the lower pinnae of the frond deflexed; it is generally distributed in Britain, though not common.
In these animals the eyeball and the fur of the body are unpigmented, but the tips of the ear pinnae and extremities of the fore and hind limbs, together with the tail, are marked by more or less well defined colour.