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MOST of the Late-glacial species discussed here came from Whitrig Bog in southern Scotland. This site lies to the east of the Moffat Hills and to the south of the Lammermuirs, about three miles north of the Tweed and at 435 ft 0.d. (133 m.). It is within the area of the Scottish Readvance, but outside the Lammermuir-Stranraer moraines (Donner, 1957).The deposits showed a typical Late-glacial sequence of an organic mud and marl lying between lower and upper silty clays. The three layers are correlated with Zone 11, and Zones I and I11 respectively. Below the Zone I clay lay boulder clay, presumably related to the Scottish Readvance ; and Post-glacial marl and peat overlayed the Zone I11 clay. Pollen-analysis by Dr Godwin accords with this stratigraphic zoning.The determinations, with one or two exceptions, are based on macroscopic material, seeds, fruits, leaves etc. Only the terrestrial species from Zones I1 and I11 will be referred to.From the Zone I1 muds and marl the occurrence of tree-birch fruits supports the indication of Park Tundra deduced from the greater abundance of tree and shrub pollen relative to that in the zones above and below ; and Filipmdula ulmaria, although a marshplant, suggests ' warmer ' conditions.In Zone I11 many of the species (Table I) are of ' arctic-montane ' affinity. Many were concentrated in a marked leafy layer near the base of the silty-clay, where large quantities of the leaves, fruits and buds of Salix herbacea were present. TABLE 1.-Macroscopic remains of land plants from Zone I11 at Whitrig THE LATE-GLACIAL FLORA Armeria maritima (Mill.) Willd. Betula nana L. Draba incana L.* Empetrum nigrum agg. Luaula spicafa (L.) DC. Oxyria digyna (L.) Hill Papaver sect. scapijlora Polygonum vivaparum L.* Rumex acelosella L. Salix hcvbacea L. S a l k reticulala L.* Saxifraga hygnoides L.* Saxifraga cf. rivularis* or cernua Saxifraga cf. rosacea (Selaginella selaginoides (L.) Link.) Thaliclrum alpinurn L.* POLLEN : Koenigia islandica I . . , Ephedra distachya L. Basophilous species.

In a series of profiles at the china-clay pits at Hawks Tor, Bodmin Moor, Cornwall, a stratigraphy was found resembling that typical of the late-Glacial Allerod oscillation. Gravelly-soil layers showing solifluction phenomena overlie the organic muds and peats of a small channel, and these gravels are in turn thickly overlaid with peat. Pollen-analyses from this site, reinforced by series from neighbouring sites, make it clear that the peat above the solifluction gravel must be referred to the early post-Glacial period. Identification of fruits, seeds, etc., from the organic layers near the overlying and underlying gravels shows the presence of many plants now restricted to more northerly parts of the country, such as Betula nana, Salix herbacea and Thalictrum alpinum . Pollen-analyses show assemblages of genera and species of herbaceous plants recognized as typical of the open ‘tundra’ or ‘park-tundra’ conditions found elsewhere in Europe in this period; these include the genera Helianthemum, Armeria, Artemisia, Thalictrum, Planlago and Polemonium . Evidence that the muds and peats beneath the upper gravel layer were formed in a period of amelioration is found in the formation of the organic layers themselves, in the diatom flora, which has a preponderantly cool-temperate character, and in the presence of a few mosses and phanerogams of more southerly distribution type. The evidence does not make it apparent whether closed woodland characterized this period. There seems no doubt that these deposits represent the late-Glacial period, and the authors make a tentative zonal correlation between them and zoned deposits of similar age elsewhere in Britain and other parts of north-west Europe, extending through the Allerod oscillation. The lists of microscopic and macroscopic plant identifications from the recognized zones provide evidence of the presence of a large number of plant species at a time and place of great interest and importance in the history of the British flora.

SUMMARYA single capsule of the coprophilous genus Splachnuni is reported from deposits of LateWeichselian (Late-glacial) age in Berwickshire. Other Quaternary records of moss sporophytes are briefly discussed.Whitrig Bog, first studied for plant remains by Mitchell (1948) and later by Conolly The sub-fossil flora of these strata is among the richest found in the British Isles. It includes such interesting finds as Koenigia islandica L., Luzula spicata (L.) DC, Saxifraga cf. rivularis L. or cernua L. and Papaver sect, scapiflora, a non-British taxon (Conolly, 1957(Conolly, , 1961.In a bryogeographically significant moss assemblage of some twenty-five taxa, Rhytidium rugosum (Hedw.) Kindb., Scorpidium turgescens (T. Jens.) Loeske and Timmia sp. are particularly noteworthy. All three, and Scorpidium turgescens in particular, are excellent examples of relict species known to have had widespread, more continuous ranges in Weichselian times (Dickson, 1967); at present they exhibit highly disjunct patterns. Such species as Camptothecium nitens (Hedw.) Schimp., Drepanocladus revolvens (Turn.) Warnst. and Scorpidium scorpioides (Hedw.) Limpr. demonstrate the presence of rich fens in both zones II and III. A range of base-rich, open terrestrial habitats, probably more strongly developed in zone III, is indicated by Distichium capillaceum (Hedw.) B., S. & G., Ditrichum flexicaule (Schwaegr.) Hampe, and Timmia sp. amongst others. A few taxa (Polytrichum and Rhacomitrium spp.) point to base-poor conditions.A Splachnum capsule was extracted from the clay deposited during zone III. No leaves referable to Splachnum were to be found amongst the numerous zone III moss fragments. This find is exceptional, because of the rarity of any sub-fossil Splachnaceae, coupled with the scarcity of sub-fossil capsules in general.The capsule, detached at the junction of the seta and apophysis, bears only stumps of the peristome; the calyptra and operculum are missing. There are spores (diameter c. 12 n) by the opening of the theca as well as alongside the exserted columella and the apophysis. Although the apophysis is somewhat battered and mounting of the specimen has resulted in flattening, the cell structure of the capsule is clear (Plate i). 197