The establishment of Primula petiolaris and its allies as representing a distinct section of the genus was the work of Pax in Engler's Bot. Jahrb., x, 173 (1889). His definition of the section was reasonably adequate, allowance being made for the scanty material available to him. The main information at his disposal came from Wallich's diagnosis (1) of P. petiolaris in 1824 and Hooker's treatment (2) of that species and its varieties in 1882. The chief diagnostic marks instanced by Pax were the membranous leaves with very broad midrib and with sharply and closely erose-denticulate margin, the great variability in leaf-shape and in the degree of development of the scape, the rose-coloured flowers and the globose capsule. Very apposite were his comments on the difficulty in distinguishing the component species and his conviction that the many varieties of P. petiolaris may quite well represent individual species, although the lack of careful observations on living material compelled him to leave within that aggregate even such plants as P. Tanneri. Pax's conception of the confines of his section was better exemplified by his choice of its components than by his diagnosis.

Within recent years several human ova in the previllous stage of development have been discovered and their study, taken in conjunction with the detailed observations of Heuser and Streeter (1941) on the development of the macaque embryo, has resulted in fundamental modifications of the views previously held concerning the early development of the human embryo.

The outlook on early human embryology comprises three phases: first, the phase when only very few specimens had been discovered and the tentative conclusions drawn from their study were to a considerable extent merely surmised by analogy with the phenomena known to occur in the development of other animals; second, the phase where sufficient material has been acquired to enable investigators to verify or deny some of these postulations and even to suspect certain possibilities—like variations in the degree of development of the various elements in embryos of approximately the same age such as is known to occur in other mammals, or early histological changes indicating pathological relations between the embryonic and maternal structures which may foreshadow the failure of continued embryono-maternal relations and impending abortion; and third, a phase when the specimens will be so numerous that the conclusions of the earlier periods can be established with certainty or definitely refuted. At present, early human embryological study is in the second phase, and the early attainment of the third phase is desirable to fill gaps in the present knowledge of the stages in the development of several structures (e.g. the yolk-sac, the amnio-embryonic vesicle, etc.) and to determine details necessary for a more precise comparison of the development of the human ovum with that of other primate and of lower vertebrate forms.

The presence of a fungus on grains of perennial rye-grass which failed to germinate was recorded in New Zealand by Hyde in 1932. In 1938 the same fungus was associated by Hyde with exceptionally low germination in Italian rye-grass and, later that year (Hyde, 1938 a), the poor germinating capacity was ascribed to infection by Pullularia. Seed of the Scottish harvest of 1938 showed the signs of infection by Pullularia described in Hyde's papers (Noble, 1939), and cultures obtained from mycelium within infected seed, sterilised on the surface, were identified as Pullularia pullulans (De Bary) Berk.

Fossils have been known to occur in the early “post-Caledonian” sediments of Cowie Harbour, Stonehaven, for more than sixty years. Dr R. Campbell (1911, 1912 a, b, 1913) gave an account of the stratigraphy and recorded a number of fossils, including plant-fragments, arthropods (subsequently discussed by Steamer, 1934, 1935), and fishes (Traquair, 1912; Kiaer and Heintz, 1932 a; Heintz, 1939). The fossinferous “Dictyocaris-band,” exposed on the tidal foreshore, has been visited repeatedly by members of this department, who have collected a considerable quantity of fragmentary remains. During the last few years interesting new forms have been obtained by Dr F. H. Stewart, by the writer, and by senior and research students. Faunal lists and a discussion of the age of the beds occur later in this paper. The Dictyocaris-band outcrops also in the Tewel Burn. A cephalaspid scale from this section (Geol. Surv. Scot., T. 2738c and T. 2739c) is described below.

The Western or Toro-Ankole volcanic province of Uganda consists of several areas of tuffs, explosion craters, and rare lava flows situated to the east and south-east of Ruwenzori (text-fig. 1). From north to south these volcanic fields are distinguished under the names (a) Rusekere; (b) Fort Portal; (c) Ndale, formerly known as the “Kyatwa area”; (d) Katwe-Kikorongo; (e) Bunyaruguru, formerly known as the “Kichwamba area”; and (f) Katunga. The Bunyaruguru field extends southwards from Lake George in and adjacent to the north-eastern portion of the Lake Edward section of the western rift. The Kabirenge and Lyakauli lavas (text-fig. 2) occur on the eastern edge of the rift depression immediately north-west of Nyondo crater (E. 30° 04′ 25″; S. 0° 14′ 30″). As a group, they constitute one of the four lava occurrences now known in Bunyaruguru, the other three being those of Chamengo, Mafuru, and Kazimiro (text-fig. 2). Otherwise, lava occurs only as fragments and lumps in the tuffs and as bombs and ejected blocks. The Kabirenge-Lyakauli lavas are also of special interest because, as described later by Professor Holmes, they consist of various members of the mafurite series, characterised by the presence of the recently discovered mineral kalsilite, a polymorph of KAlSiO4.

Within the last twenty years our knowledge of the structure and distribution of the armoured Placodermi (including Arthrodira, Ptyctodonta, Phyllolepida, Macropetalichthyida, Rhenanida, and Antiarcha) has increased tremendously. The writer is engaged on a morphogenetic analysis of the group, early publication of which is uncertain. A recent paper by Gross (1941) deals among other matters with the nature of the Antiarch pectoral limbs, and since my own conclusions partly support and partly oppose his very interesting hypothesis, it seems desirable to discuss separately the nature and possible evolution and morphogenesis of these unique vertebrate appendages. To do so it is necessary to review the paired limbs of other placoderms and of Acanthodii, with special reference to their functional significance.

The present paper records an investigation into a new and unusual suctorian, found epizoic on the cuticle of the Cirripede, Conchoderma aurita. The Cirripede host was obtained from a Blue Whale (Balaenoptera musculus), in the S. Pacific. The collection was made at the Whaling Factory Ship Southern Empress, by the Whaling Inspector, Commander H. Buckle, and the material was then sent to Britain with the collections of H.M.R.S. Discovery. The new form, Metephelota coronata, was first discovered by Professor H. Graham Cannon in the course of an anatomical study on Conchoderma. Recognising that M. coronata might be a new member of the Ephelotidæ (Collin, 1912), Professor Cannon, with great kindness, transferred the whole of the available material to me for further study. This has shown that the material consists of a single new species, generically distinct from Ephelota and Podocyathus, the two previously known genera of the Ephelotidæ.

When Pax (1) in 1889 constituted his section Sinenses, he was well aware that it contained at least three distinct groups, each of which could with good reason be regarded as separate sections. Of these the one which he designated Poculiformia is the equivalent of Obconica. This group Poculiformia (while sharing in the general definition of Sinenses) he marked off by the beaker-shaped calyx which is generally accrescent after anthesis. In his view the group comes nearer to group Cortusina (i.e. section Cortusoides) than to the more isolated Auganthus (i.e. Sinenses sensu restricto), which may quite well be the case. In its turn the group Cortusina is to be distinguished from Poculiformia by the character of its calyx—a tubular or cylindrical structure. Of the species quoted by Pax as within Poculiformia, only four are now considered legitimate members of Obconica—P. obconica, P. filipes, P. Listen, and P. oreodoxa.

(a) Scope of Paper.—The distinction between Highlands and Lowlands is a most striking feature of the topography of Scotland and has for long played an important part in the political, economic and social life of the country. Although the dividing line between the two regions, in a purely geographical sense, is ill-defined in some districts, on the whole it coincides fairly closely with a powerful geological dislocation which can be traced across Scotland from Stonehaven to Arran (fig. 1), a distance of 160 miles. This dislocation has for long been termed the Highland Boundary Fault. On detailed study it is found to be only one of several faults making up a complex fracture-zone, one of the most important in the British Isles, within which movements on a considerable scale have taken place from Ordovician to Carboniferous times.

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 Caledonian plutonic rocks of Western Scotland form a well-defined group, ranging from ultrabasic to acid types, which have been studied in detail by a number of petrologists. They form intrusions of varying size, usually composite and frequently, at least, having the habit of ring complexes. The rock types include peridotites and pyroxenites, gabbros, hornblendite and appinite, appinitic diorites, pyroxene-mica diorites, hornblende-biotite diorite, various hornblende-biotite grandiorites, biotite adamellite and muscovite-biotite adamellite, while the final stage is represented by numerous veins of aplite and rare pegmatites.

Since the early discoveries made by A. G. Bain a little over one hundred years ago, and which were described by Owen between 1844 and 1876, the South African Karroo beds have yielded a steady stream of new and interesting remains of Permian and Triassic amphibians and reptiles. Our fossil-bearing beds cover about 200,000 square miles. Some exposed areas are very rich, and others covered by soil and wind-blown dust are for all practical purposes quite barren. Still at any time there must be many hundreds of thousands of fossils lying exposed and waiting to be collected. Many do not last long, and weather to powder within a year if not collected; and new ones are always being exposed. In 1935, I sent Professor Camp of America to a farm where, in one day, he collected a hundred good skulls. I had been on this same farm only six months before and collected sixty skulls. One can go there every year and get a large collection. The large majority of skulls are duplicates—but new fossils may turn up at any time.