The development of the relief of the Scottish Highlands is traced over the last 400 Ma. Evidence from Late Palaeozoic and Mesozoic sediments and near-surface volcanic and igneous rocks shows that post-Devonian erosion of basement has been < 1–2 km and that the main morphotectonic units of the Highlands were already established by the end of the Palaeozoic. During the Mesozoic, the Highlands experienced several major erosional cycles, beginning with uplift, reactivation of relief and stripping of cover rocks, followed by progressive reduction of relief through etchplanation and culminating in extensive marine transgressions in the Late Triassic, Late Jurassic and Late Cretaceous. In the Early Tertiary major uplift affected the Highlands, with downwarping and block movements along basin margins, but levels of uplift and denudation around the Tertiary igneous centres cannot be extrapolated to other areas. Buchan and Caithness remained relatively stable and Mesozoic relief elements were maintained during gradual surface lowering. Earth movements of lesser magnitude continued episodically until at least the end of the Tertiary. After 50 Ma the Highland terrain evolved by dynamic etching, with deep weathering of varied geology under warm to temperate humid environments leading to a progressive differentiation of relief, with formation of basins, valleys, scarps and inselbergs often closely adjusted to lithostructural controls.

The Doularg Formation is defined within the Albany Group (Tappins Complex); the formation consists of the unfossiliferous Fence Member at the base, succeeded by the Gorse Member (formerly the “Albany mudstones with nodular limestones”), the Separation Sandstone and the Jubilation Member, a bedded, calcareous, silty mudstone. The last named has yielded the rich assemblage of trilobites described, representing thirty genera and including one new genus and seven new species—Bronteopsis matutina, Bumastoides? rivulus, Agerina laurentica, Tretaspis eximia, Ampyxina medici, Stiktocybele (gen. nov.) bathytera, Platycalymene metoeca: Nileus is the most common trilobite. The trilobite fauna indicates that the Doularg Formation should be correlated with some part of the Benan Conglomerate, the uppermost formation of the Barr Group to the north of the Stinchar Valley, and is probably of Llandeilo age. The trilobite association is most closely allied to that of the slightly older basal Superstes Mudstone, reflecting the strong ecological control affecting deeper water faunas. The affinity of the Jubilation Member trilobites with those of the middle Table Head Formation (Llanvirn) of western Newfoundland, is evidenced by the presence in both of Nileus, Cybelurus, Peraspis, and Bronteopsis. These are the four most common genera in the Jubilation Member, comprising over half the total trilobite specimens, and provide striking evidence of the longevity of deeper water genera.

The Steel Mountain terrane of the southern Long Range Mountains forms a fault-bounded massif of (meta)plutonic rocks including the Disappointment Hill complex (DHC), a sequence of granulite-facies lithologies containing charnockite emplaced at 1498 Ma (U-Pb, zircon). Quartzofeldspathic gneiss of the DHC contains garnet + biotite + orthopyroxene ± cordierite assemblages indicative of metamorphic P–T conditions of ca 750°C and 400 MPa. The relatively high thermal gradient (ca 70°C km−1) inferred for the DHC is attributed to a magmatic heat source.

On grounds of lithology, age and metamorphic grade, the DHC correlates to granulites of the Long Range Inlier (LRI) exposed farther north. Both complexes occur in blocks thrust westward over Taconic allochthons capped by ophiolite nappes. The block containing the DHC, however, preserves younger cover rocks, suggesting that it originated at a higher structural level than the LRI. This model is supported by lower pressure estimates for the DHC relative to the LRI (400 MPa vs 500–800 MPa). The DHC forms a link between Grenvillian rocks of the northern Long Range of Newfoundland and those of Cape Breton Island. The structural position of these massifs suggests that their emplacement was a post-Taconic event.

Newly discovered crustaceans from the Granton ‘shrimp-bed’ (Dinantian, Lower Oil Shale Group) are described: Bairdops elegans, Minicaris sp., Palaemysis, Tealliocaris cf. woodwardi, Pseudogalathea ornatissima, Anthracocaris scotica, Paraparchites cf. okeni, Beyrichiopsis plicata, and Eocypridina cf. aciculata, and new observations on Waterstonella grantonensis are reported. Tealliocaris woodwardi alone is recorded from bed o, a level ca 1 m below the ‘shrimp-bed’. The Granton ‘shrimp-bed’ biota is reviewed—the geological and lithological context of the deposit, the distribution and taphonomy of the biota, its life environment, palaeoecology, the likely causes of mortality, and comparisons are made with contemporaneous shrimp biotas. The nature of this unusual Konservat-Lagerstätte reflects conditions in the sheltered, periodically emergent lagoon which it represents.

While congratulating the authors for the wealth of geochemical data on a very important Precambrian lithological assemblage of India, known commonly as khondalites, which constitute a major part of the Eastern Ghats mobile belt bordering the eastern fringes of the Indian Peninsula, we have a few comments to offer on the hypothesis propounded by the authors (Dash et al. 1987).

(1) The interpretation of Dash et al. (1987) that the quartz–sillimanite–garnet (khondalite) assemblage of Orissa represents a metamorphosed deeply weathered soil profile(s) is based on a considerable body of new geochemical data: 59 new major and trace element rock analyses and 9 new major element rock analyses(ca. 1800 determinations) compared with the previous basis of 2 rock analyses for major elements only from Orissa supported by 3 for major elements only from other parts of India and 4 from Sri Lanka (ca 90 determinations—table 4).