Igetation growing in clefts and niches (Warming, 1909: 240).
The principal groups are for the greater part of the year covered with snow, which remains in the deeper clefts throughout the summer; the intervals between them are filled by connecting chains which sometimes reach the height of 3000 ft.
The river Derwent, rising in the tarns and "gills" or "ghylls" (small streams running in deeply-grooved clefts) north of Sty Head Pass and the Scafell mass flows north through the wooded Borrowdale and forms Derwentwater and Bassenthwaite.
The branchial bars which constitute the borders of the clefts are of two kinds: - (i) Septal bars between two contiguous clefts, corresponding to the primary bars in Amphioxus; (2) Tongue bars.
An appeal made by Miller for observations on the development of the Caeciliae, and of those Amphibia which retain gills or gill-clefts throughout life, has unfortunately yielded no fruits.