The unique specimen on which this description is based is in the Geological Department of the Manchester University Museum (No. L. 8549). It is on a slab of dark grey flagstone measuring 26 × 21 cm. from the Hill of Forss, Waas, Caithness, the plant being spread out on the surface of the stone like a very complete herbarium specimen (Plate fig. 1). It was referred to and briefly described, but not named, in 1888 by Mr G. Edward, who discovered it, and from whom it passed with other Old Red Sandstone fossils into the Manchester collections. In his paper, Mr Edward called attention to “three of the largest and most perfect Old Red Fossil Plants that may be seen in any museum in the kingdom,” which he had found during his collecting expeditions extending over some thirty years. Two of the fossil plants he refers to can be identified in the Manchester University Museum. The one we are concerned with here is described as “a lovely bush-like plant with hundreds of ribbon or grass-like leaves that have pod, or pocket, or flower-like terminations.”

Though first described so long ago as 1842, the remarkable fossil fish named by Germar Dorypterus hoffmanni has never become well known among palæontologists. This fact, due no doubt to its extreme rarity, is exemplified in the figures of the fish which appear from time to time in text-books: there is a decided tendency for the more recent figures to show less resemblance to Dorypterus than the earlier ones. The present paper is an attempt to make the structure of this interesting fish better known. It gives the results of a study of the four known English specimens, and, as far as possible, it embodies these results in a new restoration which, it is hoped, will help towards making future illustrations of Dorypterus rather less misleading than those now current.

The Island of Iona, celebrated for its ecclesiastical remains and venerated as the centre of St Columba's activities and as the cradle of Christianity in Scotland, is designated by various names. In Gaelic it is known as “Hy” or “I” (the Island), and has been termed also “Innis-nan-Druidneach” (the Island of the Druids), “I-Colm-Kill” (the Island of Colum of the Cell). The term “Iona” (or “Ioua”) was used by Adamnan in his Latin Life of St Columba, and was thought to be derived from the Hebrew “Ionah” (a dove). A more probable derivation is from the Irish “I-thon” (the Island of Waves).

The original specimen of the stem with secondary wood, to which the name Palæopitys Milleri was given by M'Nab in 1870, was found by Hugh Miller in a nodule half disinterred by the sea near Cromarty; its age was shown by the remains of Coccosteus decipiens in other nodules of the deposit, and by scales of Diplacanthus in the nodule containing the wood.

The Barra Isles are so designated after the largest member of the group, Barra or Barray. According to some authorities Barray is named after St Barr, who has always been regarded by the natives as the tutelary saint of the island and to whom the principal church is dedicated. A more probable derivation is that from its geographical position, i.e. from “Ay” or “I” (an island), and “Barr” (a head or point).

As is well known, one of the chief problems relating to the vertebrate nervous system is the question of its continuity or discontinuity both in the adult and in the embryo. The upholders of the latter theory believe that the neurones of the adult are not in continuity but only come into close contact by means of the synapses, while in the embryo the young nerve grows out through the tissues with a free end, and only secondarily unites with its particular end-organ. Much experimental, physiological, and pathological evidence has been brought forward in support of this view, and its upholders include most of the neurologists of the day, whose knowledge, however, relates chiefly to the higher vertebrates and who have made no, or at most very little, detailed study of the phenomena presented by the more primitive forms.

The central part of the West Lothian coast included in the parishes of Abercorn and Carriden, with which this paper deals, extends westwards from the Midhope Glen at Abercorn to Bridgeness, a distance of a little over four miles. As the conspicuous promontory of Blackness is situated near the middle of this strip of coastline, we may here, for the sake of brevity, describe the area in question as the Blackness district. Geologically the shore section includes the upper part of the Oil Shale Series and the Lower Marine Limestones that overlie the oil shales and extend upwards to the coal seams of the Bo'ness area.

The more or less flat-lying sedimentary rocks that build up the plateau country of the northern, central, and eastern parts of Spitsbergen range in age from Downtonian to Tertiary. The rocks with which it is proposed to deal in this paper constitute the basement underlying this sedimentary succession in the east central part of Spitsbergen, in the region at the head, and to the east, of Klaas Billen Bay, the north-eastern branch of the Ice Fiord (Map, fig. I). An extension of these basement rocks is to be found in the mountains east of Wijde Bay, and similar rocks are to be found in other parts of Spitsbergen, notably in the western mountain ranges. Formations up to the Tertiary, as well as the Pre-Devonian, are involved in the folding of these western ranges; but the rocks dealt with in this paper may be designated as older than the oldest unfolded rocks in the country.

Prince Charles Foreland is a long, narrow, mountainous island with a N.N.W. to S.S.E. extension, which lies parallel to the western mainland coast of Spitsbergen, but separated from it by the Foreland Sound, with an average width of ten miles. Its southern extremity lies on the same parallel of latitude as Mt. Alkhornet at the entrance to Ice Fiord, and its most northerly point on the same parallel of latitude as King's Bay. The island is thus about 54 miles long, and is on an average 5 miles wide, the maximum width of 6½ miles being attained near Pt. James Murray, and also south of Ferrier Haven. Its area is approximately 270 square miles (see map, fig. 1).

The district described is of considerable relief, according to British standards. Pitlochry lies 300 or 400 ft. above sea-level, while two summits, south-west of the River Garry, reach 2559 ft., and Ben y Gloe, north-east of the same, attains to 3671 ft. Exposures are everywhere sufficient for the mapping of groups, but they seldom permit of the following of individual beds or the recognition of the pitch of isoclinal folds.

The Geological Survey has mapped the whole district on the six-inch scale, and published Sheets 55, 56, 64, and 65 of the one-inch Map of Scotland—all except Sheet 64 accompanied by explanatory memoirs.

The ammonites dealt with in this paper belong to the family Echioceratidæ (Buckman, T.A., 1913), a varied group of slender, generally evolute forms, usually ornamented by ribs but very rarely tuberculate. In many members of the family the periphery has only a feeble keel, but in some a sharp keel, with or without sulci, may be present.

Ammonites of this family have most frequently been recorded as Ammonites raricostatus, and the raricostate species are by far the best known. The species at present classified with the Echioceratidæ, however, can be roughly grouped, with reference to their form only, as follows :—

1. Raricostate forms, with strong widely spaced ribs and feeble carina, e.g. A. raricostatoides, A. zieteni.

2. Forms with closely spaced ribs, with carina absent or feeble, e.g. A. viticola, A. prorsum.

3. Forms with elevated whorls, bearing regular ribs of moderate strength and with carina and sulci, e.g. A. aplanatum.

4. Forms becoming smooth on the last whorls, which are thin, with an acute keel and obsolescent sulci, e.g. A. macdonnellii.

Much study has already been devoted to the plumage of birds and its development, and the extensive literature to which this study has given rise might at first sight make it appear that no room is left for any new contributions to a subject which has already attracted so many investigators. The special branches of the subject, however, which have attracted most attention, have been:—(1) The histology of developing feathers, to which Studer, Davies, Wohlauer, and Bornstein have contributed; (2) pigmentation, investigated by STRONG; and (3) more recently what may be called the continuity between early “down” and adult feathers, a condition which does not appear to have been clearly realised before Jones and Gadow published the results of their researches. Recently also Waterston and Geddes, working on the embryology and anatomy of the Penguin, have touched incidentally on the appearance of down-papillæ and down at successive embryonic stages in the Penguin and the Duck; but, covering a wider field of research, they have not devoted to feather development in particular that careful observation and detailed study which the interest of the subject and the deficiencies of our knowledge appear to warrant.

In 1917 I published an account (16) of the so-called pharyngeal gland-cells of earthworms, unevenly but intensely staining cells (whence the name “chromophil” which I gave to them) which form lobular masses on the pharynx, and smaller aggregations in other places in the anterior segments. I came to the conclusion that the cells were not, as was usually held, epithelial in origin—were not cells which had fallen out of the epithelial layer while still retaining their connection with the pharyngeal cavity by means of a long neck functioning as a ductule. On the contrary, they were, I believed, mesoblastic in origin, and congeneric with the peritoneum; and were devoid of ducts leading into the pharynx.

In a former memoir published in these Transactions (30) the floral development of the “Cannon-Ball” tree, Couroupita guianensis, Aubl., was described. The most striking floral feature of this remarkable Myrtaceous genus is the androecium, the form, proportions, and position of whose parts produce a curious zygomorphy with cellular gigantism. The Lecythidean andrœcium, and the torus which bears it, were considered of systematic importance and of physiological interest, and deserving of special study with reference to the Myrtaceæ as a whole.