Pale crag martin to do so, it would cast doubts on their specific distinctness. There are several subspecies differing in plumage shade or size, although the differences are clinal, and races interbreed where their ranges meet. The pale crag martin of the nominate subspecies "P. o. obsoleta" is 12–13 cm (4.7–5.1 in) long with light brown upperparts, becoming paler on the lower back, and a short square tail that has small white patches near the tips of all but the central and outermost pairs of feathers. It has a pale grey throat, upper breast and underwing coverts, and the rest of the underparts
Buff (colour) with a black top" in order to indicate their ownership. There is some uncertainty among experts, however, as to the exact shade of what is now called "White Star buff". There is no surviving paint or formula, and although there are many painted postcards and at least seven colour photographs of White Star liners, the shades of the funnels in these varies due to many factors including the conditions under which they were originally made and the ageing of the pigments in which they were printed. Speaking mostly to scale modellers, the Titanic Research and Modeling Association currently recommend a