Page:The Habitat of the Eurypterida.djvu/177

Rh The present outcrops of the Old Red sandstone in the British Isles are for the most part discontinuous and decidedly patchy. They fall roughly into five areas (see index map, fig. 16): (1) The Caithness-Orkney

Islands region with a northward continuation into the Shetlands and a southward one into Sutherland and Rosshire, including the coastal strips on both sides of the Moray Firth; (2) The