Though the conspicuous volcanic phenomena of the Fifeshire coast-line have for long attracted the attention of petrologists, the igneous geology of the interior has not been studied in any detail. The petrological sections of the relative Geological Survey Memoirs, together with Geikie's Ancient Volcanoes, describe numerous inland vents and intrusions, while a large number of the doleritic sills has recently been made the subject of a most interesting paper by Mr D. Balsillie, but a belt of country stretching from St Andrews to Loch Leven proved to be practically virgin ground from the point of view of the igneous geologist. It is the intrusions of this area, together with a few pyroclastic deposits, which form the subject of the present communication. Only rocks which have hitherto been undescribed are treated petrologically, though in the case of several better known intrusions alterations of the published maps have been found necessary.

In recent papers published in the Proceedings and Transactions of the Society the importance of Size as a factor determining the morphology of the vascular system of Pteridophytes has been discussed (2, 3, 29). The purpose of this memoir is to submit data concerning the vascular system of roots, and to determine to what extent Size may have acted as a causal factor in influencing the morphology of these structures. It has been pointed out that the most useful material for these causal studies is to be found where there is only primary vascular tissue, free from complexities such, for example, as the formation of secondary wood. In the case of leafy shoots the vascular system is often profoundly influenced by the insertion of the appendages, especially where the latter are of the megaphyllous type. In many of these instances the resulting vascular structure is due to a complex of so many interacting factors that the specific effect of any one is very difficult to determine. To understand the influence of any one factor in particular we must turn, as Professor Lang has pointed out, to the study of favourable cases (19). These are to be found where the structure is of primary nature, unaffected by the activity of secondary meristems, and where the organ in question is influenced as little as possible by the insertion of appendages.

The area examined in the course of this investigation comprises parts of Perthshire and Forfarshire fringing the Grampians and Strathmore from Stenton on the Tay, 2½ miles east of Dunkeld, to Auchnacree, a mile north-east of Noran Water, an easterly tributary of the South Esk. It is represented on a scale of 1 inch to a mile on Sheets 48, 56, and 57 of the Ordnance Survey of Scotland. The field mapping of over 130 square miles was carried out on a scale of 6 inches to a mile, and the results are embodied in the appended map on a scale of 1 inch to a mile.

Before continuing the description of the alimentary tract, there are two general questions which must first be discussed very shortly. So far we have only dealt with the first two parts, the buccal cavity and the pharynx, and the latter name has such a well-defined significance that it is easy to state the boundaries of that part of the canal to which it should be applied, and therefore to fix the limits of the part in front. Unfortunately there seems to be no sort of unanimity with regard to the exact application of the names of the parts which follow, so that it is not easy to be sure to what parts the names should properly be applied, and it is extremely difficult to make comparisons between different forms without repeating a large part of the work already done by other observers. To take a concrete case: the part to which the name “œsophagus” has been applied has been limited, by different workers, by the extent of the stratified epithelium, by the extent of the striated muscle, by the absence of a serosa, by the absence of glands, and even by the relative diameter of the tube. Needless to say, these various boundaries do not coincide (in many cases some of them do not exist), and hence the difficulty of unravelling the descriptions in the literature of the subject is very great. So in what follows the names used will be defined, and I hope the nomenclature suggested will be such as to be acceptable and of scientific utility throughout the Chordata.

In the following pages two separate subjects are considered which are connected only by their relation to the same animals. The first concerns the feeding mechanisms and habits of the Lophogastridæ, but unfortunately no living animals could be examined.

As a result of some work on the feeding mechanisms of the Malacostraca (Cannon and Manton, 1927, in the press, etc.) it was concluded that in the Syncarida, Peracarida, and Eucarida a primary filter-feeding habit exists. This has been modified or given up entirely in the higher forms of each division in favour of feeding on larger masses of food. In the adult Hemimysis, Anaspides, and Nyctiphanes the filter-feeding mechanisms are essentially similar. The maxilla forms a combined suction pump and filter and draws a current of water through a filtering comb of setæ borne on its proximal endite. This comb is scraped by the basal part of the first trunk limb, which transfers the collected food forwards on to the proximal endite of the maxillule by which it is pushed into the mouth.

The most serious gap in our knowledge of the anatomy of the British Actiniaria has been the almost complete absence of structural data referring to the genus Phellia. The present paper deals with all the British species belonging to this genus, and adds some notes on other forms.

I wish to make the following acknowledgments. I have received a grant from the Royal Society, which has rendered possible the work described. I am indebted to my wife for preparing serial sections of the species of Phellia, and for drawing text-figs. 2, 3, 5, and 8. I also wish to thank Miss E. M. Stephenson for text-figs. 1, 9, and 10. Text-figs. 1, 6, 7, 11, and 12 have been reproduced before in my Ray Society Monograph on the British Sea Anemones (and text-fig. 12 in the Journal of the Marine Biological Association also), but their repetition here is essential for the demonstration of the several points which they illustrate.

The mapping of sub-drift topography is an important problem in this country and one which, under suitable circumstances, lends itself readily to solution by the method of gravitational survey with the Eötvös Torsion Balance. It has been pointed out in previous papers that structures such as anticlines, synelines, faults, and dykes may be determined by a linear traverse with the balance transverse to the strike; but in the case of buried topographic features a network of observations with subsequent plotting of the gradients and isogams, i.e. lines of equal gravity, is necessary to determine even approximately the shape and dimensions of rock-masses underlying a thick covering of drift.

The present paper is the third of a series recording the results of investigations into the relations of the structures present in the oocyte during the growth period, particularly in their bearing on yolk formation. A Crustacean was selected for various reasons: firstly, as representing a large class about the oogenesis of which little is known, this in contrast to most other Arthropod groups which have been studied by several authors; secondly, in the hope that it would prove to have no yolk nucleus, and would exhibit nucleolar extrusion, a hope which has been fairly satisfactorily justified; thirdly, for the utilitarian reason that it is a common animal, easily obtainable, and able to live under laboratory conditions during considerable periods.

The work recorded in this paper forms part of an investigation to determine how far the feeding mechanism of the simple Peracaridan Hemimysis lamornæ, which we have recently described (1927), represents a primitive Malacostracan type.

We have not been able to observe any living Syncarid, but have been fortunate in obtaining preserved specimens of the three genera Paranaspides, Anaspides, and Koonunga, together with a series of transverse sections of Anaspides. From a comparison of the structure and arrangement of their mouth parts and trunk limbs with those of Hemimysis and other Malacostraca which we have observed alive, we have been able to deduce their methods of feeding in considerable detail.

The specimen to be described in this paper was presented to the embryological collection of the Anatomy Department of the University of Sydney by Dr A. A. Palmer of the Public Health Service of New South Wales.

It is a pleasant duty to acknowledge indebtedness to Dr Palmer, not only for his kindness in making over the specimen to the Department, but also for his swift recognition of its interest.

The acquisition of a preserved fœtal specimen of the African Elephant has enabled the writer to prepare a series of papers on the anatomy of this interesting Mammal. The present paper forms Part III of the series. Part I (1926) dealt with the anatomy of the head, Part II (1928) with the body muscles. The contents of the thorax and abdomen have now been investigated, and Part III is concerned with a description of them and of the remaining parts of the skeleton. This part is the last of the series.