A. R. Hunt — Devonian Rocks of 8. Devon. 243 



■with slaty rocks with interbedded grit bands, in which latter mica 

 is occasionally very conspicuous. The rocks here are less generally 

 micaceous than those between Hope's Nose and Meadfoot in Torbay, 

 but a reddish grit-band sliced for the microscope proved almost 

 identical, except in colour, with the brown Kilmorie sandstone 

 already mentioned ; even to a few grains of triclinic felspar. 



The cliffs at Torcross are passed unexamined, as there are some 

 seven volcanic bands of more or less importance in them, and 

 the sedimentary rocks in consequence liable to intermixture with 

 volcanic ejectamenta. 



Just south of the village of Beesands some interesting grits occur, 

 about the spot where Sir Henry de la Beche placed the boundary-line 

 of the metamorphic rocks. Again we meet with fine sandstones and 

 interbedded grits and slates, the sandstones and grits occasionally 

 containing tourmaline and mica, like the rocks at the north-east 

 end of Slap ton Sands, and those in Torbay, already described. 



At a point on the coast, south of Start Farm and west of Start 

 Lighthouse, among schists much crushed and altered, there occur 

 occasional bands of quartz-schist, which in general appearance, in 

 their constituents of quartz-grains, mica, and tourmaline, as well as 

 in their intercalation between beds of a more slaty nature, recall 

 to mind, both macroscopically and microscopically, the micaceous 

 and tourmaline- bearing grit-bands of Torbay, Slapton Sands, and 

 Beesands. 



The undoubted Devonian sandstones may be traced into the un- 

 doubted metamorphic quartz-schists by four independent lines of 

 inquiry, viz. by way of iron ores, tourmaline, mica, and quartz. 



Iron Ores. 



A slice of a grey micaceous sandstone (No. 5) from south of Bee- 

 sands contains much brassy-looking pyrites crystallizing in cubes, 

 rectangular prisms, and derivative forms. ^ The pyrites is occasion- 

 ally seen to pass into red ha;matite. With strong oblique sunlight 

 on the slide the characteristic colours of these minerals are Avell seen. 



A slide (No. 22) from a grit-band between slates on the north 

 shore of Southpool Creek, not far from the metamorphic boundarj^ 

 contains a minute rectangular prism of pyrites, and flakes of red 

 haematite. 



In Hope Cove, south of Hope Headland, and therefore within the 

 metamorphic boundary, a siliceous band occurs which, while showing 

 no trace of its original quartz-grains, retains its pyrites in cubes and 

 rectangular prisms.^ The majority of these crystals display the 

 brassy colour of pyrites, and occasionally characteristic striee are 

 seen. In one group of twinned crystals, a crystal is composed 

 partly of yellow pyrites and partly of bright red heematite — whether 

 in this case the latter is a pseudomorph or only a surface incrustation 

 is uncertain. 



In a slide from one of the slightly altered bands of quartz-schist 

 south of Start Farm (No. 6) a cube of red hgematite occurs which is 

 1 Plate VI. Fifif. 3. ' 2 p^^te VI. Fiff. 4. 



