A description is given of a new genus of mammal-like reptile, Mirotenthes, of which a remarkably complete and well-preserved skeleton was collected in 1936 by Professor Camp of the University of California, from the late Permian deposits of the South African Karroo.

Unlike the majority of Permian mammal-like reptiles, Mirotenthes was an agile form of small dimensions. Many of the skeletal characters exhibit a significant approach towards the mammalian threshold. The limb structure is very advanced and the digital formula is mammalian. The differentiation of ribs to form a definite rib-cage of mammalian type is particularly noteworthy and may indicate the presence in this genus of a mammalian respiratory mechanism.

The systematic study of this complete skeleton does much to bridge the gap between the primitive basal groups of mammal-like reptiles and the advanced Triassic groups from which the mammals derive. It has been known for many years that small, fast-moving carnivorous forms were present in the late Permian fauna, but the evidence has been fragmentary. The complete skeleton described in this paper throws new light on these hitherto poorly known genera.

Monthly quantitative samples of the invertebrate fauna were taken from two stations in the River Endrick over a period of fifteen months; the substrate at one station in the lower reaches was sandy, whilst that at the other in the middle reaches was stony. The fauna at these stations differed qualitatively, but showed certain quantitative similarities, especially with regard to seasonal change. The fauna of stones is richer, and much more varied than that of sand, though both substrates appear to be unstable and may be drastically affected by spates. The average standing crop of the invertebrate fauna during 1960 was found to be 8 g. per square m. in sand and 16 g. per square m. in stones. Compared with the few other results which are available for rivers elsewhere in the world these figures would indicate that the standing crops of these substrates in the River Endrick are of intermediate richness.

Malignant catarrhal fever (MCF) is reviewed and recent findings described. It is defined as a fatal disease which affects many species of Bovidae and Cervidae, characterized by widespread necrosis and lymphoid cell proliferation and can be caused by at least two infectious agents. In Africa, a herpesvirus which infects its natural host, the wildebeest, without obvious symptoms causes substantial losses in cattle due to MCF. Elsewhere, the cause of MCF is unknown but circumstantial evidence implicates sheep as the source of infection. While cattle are infected only sporadically with this “sheep-associated” form ol disease, infection of farmed deer is common, representing the most serious disease threat to the industry.

It is considered that infection of sheep and wildebeest with their respective agents operates to their advantage, causing no disease in their natural host, while transmission to other ungulates has fatal consequences, eliminating these potentially competitive species.

Recent studies of the disease in deer and the transmission of MCF from deer to rabbits are described. The evidence suggests that the disease process involves a novel dysfunction of the immune system which results in a massive lymphoid proliferation and an atopic allergic response. It is considered that similar processes may also be involved as a component of other diseases of man and animals.

Viability loss during desiccation in the recalcitrant seeds of Castanea saliva, Aesculus hippocastanum and Quercus robur was accompanied by increased lipid peroxidation and build up of a stable free radical within their embryonic axes. We argue that the accumulation of the free radical marks the termination of a series of destructive events following the initiation of oxidative attack during moisture stress in recalcitrant seeds.

The most common kinds of speciation result in new species that initially have a small range. These will develop a limited or an extensive range depending upon the geographic extent of the environment to which they are adapted. A significant element in the extent of the potential range of a new species is the adaptation inherited from the parental species. Selection of a parental species for a local environment at one site can lead to a narrow ecological adaptation and often to a limited potential range. These species are likely to produce derived ones that also have a limited range, and these derivates will increase the regional species endemism and diversity. Selection of a parental species for migration to other sites can lead to a broader ecological adaptation and often to a broad potential range. These species are more likely to produce derived ones that also have an extensive range, and these derivates will increase regional species diversity.

The vertical distribution of pelagic decapods has been investigated at six positions, each located approximately at 10° interval of latitude between 11°N and 60°N in the eastern North Atlantic. An account of the day and night depth distribution of four mesopelagic species, Acanthephyra purpurea, A. pelagica, A. sexspinosa and A. acanthitelsonis, and four bathypelagic species, A. prionota, A. curtirostris, A. acutifrons and A. stylorostratis, is presented. The four mesopelagic species have vertical distributions which vary latitudinally in association with geographical gradients in temperature, the mesopelagic zone from about the latitude of 28°N cooling both polewards and equatorwards. It is concluded that environmental temperature is a major factor in controlling the vertical ranges of these species although other physical variables, principally light, must also be involved.

A faunal boundary exists in the region of 18°N, where the North Atlantic species A. purpurea and A.pelagica are replaced by the Central and South Atlantic species A. sexspinosa and A. acanthitelsonis. The nature of the physical boundary is not clear, but it is tentatively proposed that it represents a relatively broad area where the North Atlantic Central Water and South Atlantic Central Water meet.

The deteriorative processes leading to the death of a population, individual or part of an individual can be genetically programmed or induced by environmental perturbations, physical damage, pests and diseases. Senescence in multicellular plants is typically a phenomenon resulting from cell differentiation and loss of totipotency. Recycling of nutrients released from senescent cells, abscission layer formation, containment of pathogens and dispersal of progeny are crucial aspects of senescence management. Senescence-related autocatalytic changes induced by substances generally thought to regulate senescence may not mirror the sequence of changes occurring naturally through correlative processes in the intact plant. The chloroplast has a key role in reversing senescence-related degradation of other organelles. Conventional symptoms of senescence used in plant sciences have obscured common theories of senescence regulation for all types of organism.

The epidermis of the sea horse Hippocampus kuda is characterised by flame cone cells, each of which protrudes 20-40 μm above the surface and is covered by a prominent mucous cap. Unlike normal surface cells, the mucoid caps can support epiphytic microbial growth.

Histochemically the mucous cap is a neutral mucopolysaccharide-protein complex possessing 1,2 glycol groups and SH-groups; acid mucopolysaccharides are absent. The acid mucopolysaccharide glycocalyx of unmodified surface cells is absent from the mucous cap surface.

Ultrastructurally two types of vesicle can be distinguished in flame cells. Type I is oval (0·3 × 0·6 um) with contents of medium electron density and occurs principally in mature flame cells. Type II, seen only in developing cells, is spherical (0·4 μm) and contains rod-like subunits characteristic of the cap mucous. Secretion is mediated by channels formed by smooth endoplasmic reticulum. Unmodified surface cells also secrete their vesicular contents, which resemble the Type I vesicles of flame cells and are similar to the goblet mucous vesicles of other fish, through similar channels.

Flame cell mucous caps, by virtue of their histochemistry, possible provide a suitable substratum for the adhesion and growth of epiphytes which in turn may afford protection against cnidarian nematocysts.

Greece is estimated to have between 4,650 and 4,900 species of vascular plants, about 742 of which are endemic. The Mountain Flora of Greece covers about one-third of the total number of species and a considerably larger proportion of the endemics. Of 926 taxa (species and subspecies) treated in volume 1 (1986), no less than 304, or c. 33%, were either not recorded for Greece in Flora Europaea or were recorded under a different name or with a different rank or both. Phytogeographical analysis shows that 51% of the taxa are “narrows” (restricted to the Balkan Peninsula + Italy or the Balkan Peninsula + Anatolia), and 49% are more widely distributed. Crete is particularly rich in regional endemics, and Peloponnisos and Sterea Ellas have the highest numbers of Greek endemics. An Anatolian element is well-represented in Crete and in the north cast, reflecting the 2 principal routes of migration. Examples of Greek-Anatolian distributional patterns arc given, including some distributions that are widely disjunct.

The British rust diseases of willows are discussed. Only fungal characters are employed in the identification of the different species, thus avoiding the use of host plant taxa in the characterisation of the diseases. Using spore and sorus characters, 14 different species occurring in Britain could be distinguished. The density of urediniospore ornaments is analysed in particular. The rusts are described in detail, and keys for their identification are presented. A list of the rusts affecting willow hosts in Britain has been compiled.

After an introductory survey of seventeenth-century approaches to the subject, two important examples of tide-measuring activity in the eighteenth-century are described. The five years’ continuous observations at Brest, 1711–16, involved great perseverence in effort and accuracy. The treatment of the records by Cassini and their later retrieval by Lalande affords an interesting lesson in the publication of scientific data. The observations made at St Helena in 1761 are remarkable for having been made with high precision by leading astronomers in difficult swell conditions. Finally, a method is described of using these data to search for small differences in the oceanic tides between the eighteenth-century and the present, with a brief discussion of the results.

Water deficiency is the key factor limiting the occurrence of pteridophytes in seasonally dry tropical areas and shaping their adaptive strategies in respect of habitat preferences, life-forms, phenological patterns, and reproductive biology. In Zambia, which is situated in the savanna woodland zone, a total of 146 pteridophyte species occur mainly in special habitats: extrazonal evergreen forest patches and initial successional stages of lithoseres and hydroseres. Life-forms with perennating buds well protected against desiccation (hemicryptophytes and geophytes) dominate, while those with more exposed buds (epiphytes, chamaephytes and phanerophytes) are much less numerous and restricted mainly to the higher-rainfall areas. Selaginella tenerrima represents the life form of a therophyte, unknown in any other pteridophyte genus. Three major seasonal patterns of growth and dormancy may be distinguished: the evergreen type (ca. 40% of species), the poikilohydrous type (ca. 20%) and the deciduous (‘summer-green’) type (ca. 40%). No less than 20% of species are able to survive recurrent bush-fires, and some of them possess the features of advanced pyrophytes. In the driest parts of the savanna zone in Africa, e.g. in the Lake Chad Basin of northeastern Nigeria, seasonal pools are remarkably rich in water ferns, especially of the genus Marsilea which has undergone an intensive adaptive radiation in this environment.

James Murray published in the years 1905–1913 nineteen papers describing about one-sixth of all known species of Tardigrada; an important part was based on the collections of the Lake Survey (1904–1906) and a part of his collections is still present in the Royal Scottish Museum but the rest of his material could not be traced.

The present paper reviews all the new species described by James Murray from the Lake Survey and for each species the type locality is fixed, some complementary descriptions are given and wherever possible lectotypes have been selected.

Physical and chemical methods of analysis suitable for volumes of Drosophila hæmolymph under I μl. are described. The osmotic pressure of hæmolymph is equivalent to 1·05 per cent NaCl. The pH is 6·6·6·7. Na+, K+, Ca2+, Mg2+, Cl− and PO3−4 occur in concentrations of 56·5, 40·2, 8, 20·8, 42·2 and 2·8 mM/1. Probably the only sugar present is trehalose. A rough analysis for amino-acids indicates that they contribute an amount to the osmotic pressure equivalent to about 0·4 per cent NaCl. These results are discussed in relation to tissue culture.

The historical formation of the loch is described, using geological and geomorphological evidence. The changing areal dimensions from the seventeenth to nineteenth centuries are discussed using historical cartographic and documentary evidence. Finally, a comparison is made between the results of the three bathymetrical surveys that have now been carried out in an attempt to determine the amount of silting.

In January 1956 a visit was made to North Ronaldshay, one of the Orkney Islands, to examine the rumen ciliate protozoa of the seaweed-fed native sheep. Rumen material from thirteen sheep was examined and the ciliate species identified. The numerical ratio of holotrich to oligotrich ciliates appeared to be much the same as in the hay-fed sheep's rumen; Isotriclia intestinalis Stein was, however, always absent. Certain experiments on the protozoan utilization of carbohydrates were carried out and the results compared with those of similar experiments on rumen liquor from hay-fed sheep. The holotrich ciliates of North Ronaldshay sheep were found to store amylopectin when the rumen liquor was incubated with laminarin, to a lesser extent when incubated with galactose and to be unaffected by mannose. These three results differ from previous experience with hay-fed sheep. No seaweed carbohydrate other than laminarin was utilized by the North Ronaldshay sheep holotrichs in vitro.

Human aortic elastin, purified by autoclaving and alkaline extraction, has been resolved by ultrasonic treatment into individual filaments, which appear, in the electron microscope, to be of constant diameter (25 Å) with junction points at fairly regular intervals (1300)Å.

Amino acid analyses on fœtal, normal and old adult elastin showed that the desmosine(s) content remains constant at 3 residues per 105g. of protein which is equivalent to 1100 Å intervals between successive residues, assuming that these are evenly spaced along the polypeptide chain(s). On the other hand the amino acid composition was found to change with age. Thus the aspartic acid and glutamic acid contents increase from 3 and 19 to 11 and 27 residues respectively; histidine and methionine, which are both absent from fœtal elastin are present in small but definite amounts (2 and 3 residues respectively) in older elastins. The lysine content is 9 residues in fœtal elastin and 6 residues in older elastin. Probably the most remarkable feature of this protein is the high content of non-polar amino acids; of 1100 residues in 105g. protein about 1000 (including glycine and proline) have hydrophobic side chains.

The rocky shore ecology of Sullom Voe is described from surveys carried out at 43 sites in and around the Voe. The sites were located partly to provide a description of communities from a wide variety of Shetland rocky shore habitats. Records of the species present and their distribution and abundance were based mainly on check-lists including 8 lichen, 21 algal and 23 animal taxa. Other species present at each site were usually also recorded. A total of 10 lichens, 82 algae and 91 animals were recorded during four surveys in 1976, 1977, 1978 and 1979. Differences in the distribution, abundance and vertical extent of species from site to site were associated mainly with exposure to wave action, slope of the shore and the stability of the substrate. Several species common on shores in the south of the British Isles were absent or rarely recorded in Sullom Voe or Shetland. A few species rarely found or absent in the south of the British Isles were common in Shetland. During the three years of the survey, most changes in communities present on each shore have been small. However, since 1976, the abundance of the green alga Enteromorpha sp. has shown an increase, whilst populations of the barnacle Balanus balanoides have declined. The spillage of 1,100 tonnes of fuel oil in January 1979 resulted in oiling of the upper shore at many sites but with little mortality to intertidal species except where shores had been cleaned mechanically. The Australasian barnacle Elminius modestus has been recorded from Sullom Voe but the populations are probably very sparse. It is concluded that a wide variety of rocky shore communities are present within a small area in the region of Sullom Voe, that the communities show an overall high degree of stability, but they are impoverished with respect to numbers of species compared to shores in the south of the British Isles.

Triethylenemelamine induces chromosomal aberrations in Drosophila and in mammals. In the present paper the effects of intraperitoneal injections of the drug on the fertility of male mice are related to its mutagenic activity. Males were given prolonged or short treatment with the drug and were mated to females at frequent intervals.

Male fertility was greatly reduced after either treatment, a result similar to previous findings in the rat. Sterility for the first few weeks was due to dominant lethals causing embryonic mortality, and to oligospermia from 30 days after the injection. Embryonic mortality was reduced after lower doses, being maximal between 11 and 14 days after the injection, and little or no oligospermia resulted from this treatment.

The drug probably acted directly on spermatogenic cells; spermatids being most sensitive to the induction of lethals and spermatogonia to destruction; these estimates were based on the known rate of spermatogenesis in the mouse. The sensitivity of the stages of spermatogenesis and the translocation frequency induced by the drug have some similarities to the effects of X-rays on the testis.