In a former communication to the Royal Society of Edinburgh, I gave an account of an unusual fall of rain in the Lake District in the month of January last year. That occurrence was followed by its opposite in May, June, and July; not for a long period, not since 1826, has the district suffered more from want of water than in those months.

This drought is best shown by the following table, in which will be found the rain-fall for the several months of the year at five different places, only a few miles remote from each other. The table will also show the remarkable contrast as to excess and deficiency of rain during the period. It may be premised, that at Ambleside, where the drought appears to have been felt as much as anywhere, the ordinary fall of rain for the months in question is about three times as great; thus for May (our driest month of the twelve), taking the average of the preceding eleven years, it is 2·37 inches, for June 4·22 inches, for July 5·27 inches, making a total of 12·36 inches, against 4·54 inches of the months of drought.

The Naididæ are a family of small fresh-water Oligochæta, in which the usual mode of reproduction is the asexual, by fission; sexual forms are, in general, rare, and in the majority of species, and in some whole genera (e.g. Slavina), they have not so far been observed at all. Records of the genital organs are therefore of interest; and if they were available throughout the group it can hardly be doubted that we should be able to judge better of the affinities of genera and species, and consequently to improve our classification; since the diagnoses of species and genera, and the scheme of classification, depend at present to an unduly large extent on one single set of characters, the form and distribution of the setæ.

The study of sexual individuals of the genus Dero has resulted also in the discovery of the curious phenomenon of the atrophy of the alimentary canal at sexual maturity; this occurs also in Hæmonais (v. ant.); it has not hitherto been found elsewhere in the Oligochæta, though it is known to occur (apparently in a less extreme form) in a number of Polychætes.

It is well known that a luminous object is seen for some time after its light has ceased to fall on the retina; but less attention seems to have been paid to the fact, that light requires a certain time to produce its full impression on the eye. Accordingly, while it is stated in most treatises on optics, that the sensation of vision continues after the action of light has ceased, only a few writers have mentioned that the total effect of light on the eye is not produced instantaneously, but that a certain time is required for its complete development.

While engaged last autumn in examining with a hand-lens the contents of a phial into which I had transferred some of the refuse of the dredging-boats employed in the oyster fishery on the coast of South Devon, my attention was attracted by a minute organism which adhered to a fragment of one of the larger Sertularidans. Under this low power it resembled somewhat a Campanularia, with the polype expanded; but, on being removed with a portion of the substance to which it was attached, and placed in a glass trough under the compound microscope, I found that it had closed up, and now resembled in form a cup surmounted by a pyramidal lid, and supported on the summit of a long jointed stem (Plate XIII., fig. 3).

The Scottish Hydrometric Network consists of a number of river gauging stations which have been located at sites considered suitable to provide long term flow records. Economic recession has placed some stress on the gauging programme, and has given rise to extensive closures of gauging stations in England and, to a minor extent so far, in Scotland. The way in which the network became established provides a mixture of strengths and weaknesses which could have unpredictable consequences in an adverse economic climate. Changing technology provides some opportunity to reduce the cost of data acquisition and improve the deployment of manpower, while maintaining data standards. In these changing circumstances, particularly with extensive use of computer systems, it is important that standards are established for data returned to the Water Archive and that the network is not allowed to degenerate by default.

1. I Divide cubic equations into two varieties or species: the one, comprehending all cubic equations with three real roots; the other, all those with only one real root.

2. Let φ denote any angle whatever, and let τ = tan φ, the radius being unity: let also : then from the doctrine of angular sections we have

which being reduced to the form of an equation, is

Z3-3τZ2-3Z+τ=0.

A disease of Chinese Rhododendrons associated with a Lophodermium sp. was found by one of us in April 1933 (Wilson, 1937). The fungus was first noticed as apparently causing the production of large irregular spots on the leaves of the hybrid Rhododendron Souliei × R. Thomsonii. Later, fructifications were observed on the stems of this hybrid and of many other species, and were found also on the fallen leaves. In 1934 the fungus was discovered on the stems of several species growing at the Forestry Commission Estate at Benmore, Argyllshire. Plants sent to the Royal Botanic Garden, Edinburgh, from Cumberland in February 1935 were also found to bear similar fructifications on the stems. As a number of species of Lophodermium have been described on the Ericaceae and one on Rhododendron, it was desirable to ascertain the systematic relationships of the fungus especially to L. Rhododendri Ces., which has been recorded from Britain (Smith and Ramsbottom, 1914; Wilson, 1924) and which is not uncommon on R. ponticum in the vicinity of Edinburgh. It was also desirable to study the effects of the fungus upon the host plant since it is difficult in some cases to decide the degree of its pathogenicity.

The Society has had its attention of late so much directed to the subject of coal, that some apology, perhaps, is necessary for bringing this substance again under notice. I may premise, however, that in doing so, it is not my intention to revive the disputed question as to Boghead gas-coal, nor to take up the time of the Society with what may be considered as unprofitable discussion. I purpose to bring forward a few facts relative to a coal, concerning which there is no dispute, and which presents some vegetable organisms and products calculated, in my opinion, to throw light on the history of carboniferous deposits. Much of the recent difference of opinion on the question of coal has arisen from the mode in which some histologists have chosen to define it. I trust that the result of all our discussions will be to lead to a fuller examination of coal in all its forms,—to a comparison of specimens, both mineralogically and microscopically, from different localities,—and, finally, to an extended report on the subject in which geologists, chemists, and histologists will combine.

In the present communication I have applied the results of my first paper to the question of the transference of momentum, of energy, and of matter, in a gas or gaseous mixture; still, however, on the hypothesis of hard spherical particles, exerting no mutual forces except those of impact. The conclusions of §§ 23, 24 of that paper form the indispensable preliminary to the majority of the following investigations. For, except in extreme cases, in which the causes tending to disturb the “special” state are at least nearly as rapid and persistent in their action as is the process of recovery, we are entitled to assume, from the result of § 24, that in every part of a gas or gaseous mixture a local special state is maintained.

Nitroglycerine is commonly described as the tri-nitric ether of glyceryl, and the formula C3H5(O.NO2)3 is accorded to it. This theory of its composition is based (1) upon its mode of formation; (2) upon the statement, made by Railton, Williamson, and others, that it is decomposed by potash into potassium nitrate and glycerine; (3) upon several estimations of the nitrogen which it contains, and one comparative estimation of its carbon. The second argument cannot be accepted, as it has been shown by one of us that the decomposition does not take place in the way stated; and the analytical results which have been obtained by the various investigators are so incomplete and mostly so imperfect, and differ so greatly among themselves, that they cannot be taken as affording any proof of the composition of the substance. It seemed to us, therefore, desirable that some accurate estimations should be obtained, not only of the nitrogen but of the carbon and hydrogen. A brief résume of previous analytical results will show that this is the case.

During the Upper Ordovician–Lower Silurian, chert was widely distributed in the Zhongbao Formation in the eastern part of the North Qilian Orogen. The origin and the tectonic setting of these chert were largely unknown. In order to analyse the material provenance, sedimentary environment, their formation and the tectonic setting, we present petrology and geochemical research on chert samples collected from Shihuigou Section. The evidence provided by radiolarite occurrences, Aluminium (Al)–iron (Fe)–manganese diagram and the silicon(Si)/Si + Al + Fe + calcium ratios suggesting a non-hydrothermal input and the biogenic origin chert. The geochemical features and the petrographic signatures have shown that the chert was also influenced by a terrigenous origin. It is considered that the deposition of the Late Ordovician chert is mainly affected by tectonic collision and volcanic ash events. During the Late Ordovician–Early Silurian transition, huge amounts of volcanic ash were released by massive volcanic activity that fell into the ocean, triggering the proliferation of radiolarians. Finally, in the Late Ordovician–Lower Silurian the tectonic setting of the North Qilian Orogen was not a typical deep-water basin, nor a typical continental margin, but a multi-island deep-water basin, which is closed to the mainland.

New palaeodictyopterans, Vernooijia sassoonae gen. et sp. nov. (Breyeriidae) and Mazonopterumcooperi sp. nov. (Homoiopteridae) are described from the Middle Pennsylvanian (Westphalian D/Late Asturian) of Writhlington, near Radstock (UK). Based on the re-examination of venation in Breyeriaharlemensis, we propose the transfer of this species to the genus Vernooijia as V.harlemensis (Brauckmann & Gröning, 1996) comb. nov. We report the first record of Homaloneura sp. (Spilapteridae) from the Langsettian to Duckmantian of Coseley, Staffordshire. Additionally, we report a fragmentary wing from the Middle Pennsylvanian (late Westphalian D/early Cantabrian) of the Forest of Dean, Gloucestershire, tentatively belonging to the Lycocercidae. Our re-examination of a putative blattodean nymph described by Rolfe (1967) allows re-assignment to Palaeodictyoptera, as it has well-developed wing pads with a corrugated pattern of probably original tracheation and lacunal channels, identified as presumably nymphal exuvia of Idoptilus sp. Surprisingly, our study reveals the presence of three triangular caudal appendages bearing prominent lateral lamellae emerging from the terminal abdominal segment, previously unknown in other nymphs of Palaeodictyoptera. We assume that these lamellae were originally covered with dense setae and possibly represent modified caudal appendages in the form of tracheal gills, as known in the nymphs of damselflies (Odonata: Zygoptera). Thus, the scenario of a possible aquatic lifestyle for nymphs of at least some members of Palaeodictyoptera, as considered by Brongniart (1885, 1893) and Handlirsch (1906), cannot be definitely excluded.

Anthracotheres are generalised artiodactyls that have an extensive record in the Cenozoic of Eurasia and Africa. In North America they have been collected in middle Eocene to early Miocene localities from the California Coast, the Great Plains and the Gulf Coast of the United States, with a single record from the early Miocene of Panama. Here we report few specimens from the early Oligocene (Ar1) Iniyoo Local Fauna of north-western Oaxaca, and the earliest Miocene of Simojovel de Allende, in northern Chiapas. This material has diverse features that indicate they belonged to the bothriodontine Arretotherium, such as selenodont cristids associated with the protoconid and hypoconid, the absence of a premetacristid, and the crenulated enamel. They share with Arretotherium acridens and Arretotherium meridionale the absence of a mesiolingual metacristid, but their general morphology and size indicate a close relationship to Ar. meridionale. Nevertheless, in absence of better-preserved specimens, we decided not to assign the fossil material to this species. Specimens from Oaxaca and Chiapas are the first records of anthracotheres in Mexico. These new records link the previous ones from temperate North America and tropical Central America and indicate that Anthracotheriidae had a very wide geographical distribution in North America during the Palaeogene and the Neogene. Additionally, they represent the southern-most records of Arretotherium in North America during the Oligocene and the early Miocene.

The first representative of Tipulomorpha in Early Eocene Cambay amber from India is described. The new find belongs to the genus Dicranomyia in the family Limoniidae. This genus has a worldwide distribution today and is relatively common in Eocene Baltic amber. A new species belonging to the subgenus Dicranomyia is described as Dicranomyia (Dicranomyia) indica sp. nov.

At a time when nobody has yet landed on the Antarctic continent (1879), this presentation and accompanying paper predicts the morphology, dynamics and thermal regime of the Antarctic ice sheet. Mathematical modelling of the ice sheet is based on the assumptions that the thickness of tabular icebergs reflects the average thickness of the ice at the margin and that the surface gradients are comparable to those of reconstructed former ice sheets in the Northern Hemisphere. The modelling shows that (a) ice is thickest near the centre at the South Pole and thins towards the margin; (b) the thickness at the pole is independent of the amount of snowfall at that place; and (c) the mean velocity at the margin, assuming a mean annual snowfall of two inches per year, is 400–500 feet per year. The thermal regime of the ice sheet is influenced by three heat sources – namely, the bed, the internal friction of ice flow and the atmosphere. The latter is the most significant and, since ice has a downwards as well as horizontal motion, this carries cold ice down into the ice sheet. Since the temperature at which ice melts is lowered by pressure at a rate of 0.0137 °F for every atmosphere of pressure (something known since 1784), much of the ice sheet and its base must be below the freezing point. Estimates of the thickness of ice at the centre depend closely on the surface gradients assumed and range between 3 and 24 miles. Such uncertainty is of concern since both the volume and gravitational attraction of the ice mass have an effect on global sea level. In order to improve our estimate of the volume of ice, we will have to wait 76 years for John Glen to develop a realistic flow law for ice.

New fossils of the families Nemopteridae and Chrysopidae are recorded and a new species of Hemerobiidae, Sympherobius yulei sp. nov., is described from the late Eocene Insect Bed of the Isle of Wight. The new nemopterid belongs to the tribe Stenonemiini and is very similar to a specimen already recorded from the Early Oligocene of Alsace (France), suggesting that these warm-climate insects were not affected by the ‘Oi-1 Glaciation' cooling.

Surface sediments from a 100-km stretch of the River Clyde, UK, and its estuary were analysed for glycerol dialkyl glycerol tetraethers (GDGTs) to track the downstream changes in the source of organic matter (OM) and to evaluate the impact of urbanisation. Bacterial membrane lipids, named branched GDGTs (brGDGTs), produced in soils and rivers ranged from 1.6 to 58μgg−1 organic carbon (OC) and the isoprenoid GDGT crenarchaeol, mainly from marine archaea, ranged from 0.01 to 42μgg−1 OC. The highest brGDGT concentrations were in the upper river, in Glasgow city and in the outer estuary, suggesting higher soil-derived OM input. By contrast, crenarchaeol concentrations gradually increased from the tidal weir in Glasgow towards the sea. This spatial distribution of the tetraethers was reflected in the branched and isoprenoid tetraether (BIT) index, a proxy for soil versus marine carbon. The highest BIT values (1.0) occurred upstream, estuarine values ranged from 0.9 to 0.6 and the lowest values (0.4) were found in the outer estuary. An independent proxy for soil-derived OM, stable carbon isotope (δ13C) values, showed a comparable decrease in terrigenous OM contribution towards the sea, but was more variable compared to the BIT. Conversely, carbon/nitrogen (C/N) showed a constant trend, suggesting that it is not a reliable indicator of OM source in the Clyde. Neither BIT, δ13C nor C/N were able to reflect the input of urban effluents from Glasgow.

La Mina is one of three sites, along with Cueva Millán and La Ermita, located in the middle course of the Arlanza river. La Mina was excavated for the first time in 2006 and three test pits were carried out. In one of them, evidence of two Palaeolithic occupations was identified and several remains of woolly rhinoceros were recovered. Amino acid racemisation dating yielded an age of 52.5 ka BP, the earliest Upper Pleistocene date for Coelodonta antiquitatis on the Iberian Peninsula. This new record may have several implications for understanding the access routes to the Castilian Plateau, together with the definition of a new migratory wave of this species at the end of the Pleistocene. The location of La Mina on the Castilian Plateau may help researchers to complete the movements of this species through the Middle and Upper Palaeolithic on the Iberian Peninsula.

The trichopteran assemblage of the Late Eocene Bembridge Marls is revised. six species in five genera and four families are identified, with four species and two genera described as new: (Beraeidae: Beraeodes vectensis Cockerell, 1921 and B. anglicus Cockerell, 1921; Phryganeidae: Bembridgea insularia gen. sp. nov.; Polycentropodidae: ?Plectrocnemia incompleta Sukatsheva, sp. nov.; Philopotamidae: Wormaldia longaeva Sukatsheva, sp. nov.; incertae familiae: Paleodicella anomala Sukatsheva, gen. sp. nov.). The assemblage is unique in being absolutely dominated by the generally uncommon family Beraeidae, and particularly by the single species Beraeodes vectensis. Except for a representative of ubiquitous Phryganaeidae, all the caddis-flies recorded apparently had oxy- and psychrophilous larvae confined to springs and cold streams (or else mosses near water), thus indicating the absence of fresh lakes or slow running waters near the depositional water body.