ee are > “pow aes 5 A PASI Hove Veta in Po a Ae ys Cg ee eg ne tent bre tease Serie wid eae NY We Wane AVR Lp | tu , a | THE GEOLOGICAL MAGAZINE, DECADE V. YOL. X. JANUARY—DECEMBER, 1913. k 3 a 0 al j' uk ae ie + Saale \ ON } J THE GEOLOGICAL MAGAZINE Monthly Journal of Geology: WITH WHICH IS INCORPORATED GR \SlID), (GrId © IO) Eells dh ok NOS. DLXXXIII TO DXCIV. EDITED BY HENRY WOODWARD, LL.D., F.R.S., F.G.S., F.R.M.S. LATE OF THE BRITISH MUSEUM OF NATURAL HISTORY; PRESIDENT OF THE PALM ONTOGRAPHICAL SOCIETY ; ETC., ETC. ASSISTED BY Proressor J. W. GREGORY, D.Sc., F.B.S., F.G.S. Dr. GEORGE J. HINDE, F.RBS., F.G.S. Sir THOS. H. HOLLAND, K.C.1.E., A.R.C.S., F.B.S. Proressor W. W. WATTS, Sc.D., LL.D., M.Sc., F.R.S., V.P.G.S. Dr. ARTHUR SMITH WOODWARD, LL.D. Gtaseow, ‘F.RB.S., F.1.8., Src. G. Soc. AND HORACE B. WOODWARD, F.R.S., F.G.S. NEW SHRIBS. DECADE V.- VOL. =&- JANUARY—DECEMBER, 1913. LONDON: 2248 be DULAU & CO., LTD., 37 SOHO SQUARE, W. 1913. STEPHEN AUSTIN AND SONS, LTD. PRINTERS, HERTFORD II. LIST OF PLATES. FACING PAGE Portrait of Professor Suess Stems of Hquisetites columnaris (Brong.) . » Structure of Lophophyllum and Cyathaxonia . Chalk Polyzoa . The Mekong-Yangtze Divide The Mekong River at Tew-kow Chalk Polyzoa . Chalk Polyzoa . Portrait of Professor James Geikie ‘Solenopora garwoodt, Hinde, sp. nov. Portion of a trunk of Lepidodendron veltheimianum, Sternberg Sections of pedicle valve of Syringothyris aff. carteri (Hall), etc. Cothurnocystis Hlize and Dendrocystis scotica, Bather Chalk Polyzoa . Hoanthropus Dawsoni, A. Smith Woodward Vegetation and Desert Surface-features, South-West Texas” Arid Surface-features, South-West Texas . Portheus molossus, Cope, Chalk, Kansas . FOLDING TABLES. North American and European Drift Deposits Geological Horizons at which Calcareous Algz occur 49 14 593 LIST OF ILLUSTRATIONS IN THE TEXT. Stems with rhizomes attached of Hquisetites columnaris (Brong.) Diagram illustrating the Glacial and Interglacial Periods Generalized section, spilite lavas, northern type Generalized section, spilite lavas, southern type Genealogical development of the Monticuliporoids . , Diagram of Creechbarrow Hill Eolith from Plateau Gravel, Ightham Formation of columella in Lophophyllum and Cyathaxonia Map showing position of chalk-pebbles found in English Channel Key-map to Geological Survey Map, Cornwall Section across Cornwall Sketch-map of West Leicestershire Verruca from Norwich Chalk Porosphera globularis, Phillips Lower jaw, Pachygenelus monus, Watson, gen. et sp. nov. Molars, P. monus, Watson, gen. et sp. nov. The Yangtze and Salween Rivers An oasis, Mekong River Valley Lake in rock-basin on Mekong—Yangtze Divide End of femur of Hlopteryx nopcsai, Andrews, gen. et sp. nov. End of tibio-tarsus of #7. nopesai, Andrews, gen. et sp. nov. . Diagram of ambulacral plates of Lanieria lanier, Duncan Forearm of Lystrosaurus sp. . Upper ends of radius and ulna of Lystrosawrus sp. Lower ends of tibia and fibula of Lystrosawrus sp. . Lower jaw of lynx, Felis lynx, Gop Cave, North Wales . Upper maxilla of lynx, Cales Dale Cave, Derbyshire Dorsal aspect of Hurypterus Fischeri Ventral aspect of H. Fischeri Perischodonwus biserialis (maxille) P. biserialis (epiphysis) Plates of Helminthochiton equivoca, Robson, sp. nov. PAGE 140, 141, 146, 6 16 19 19 35 44 45 55 63 71 72 75 105 190 145 147 149 150 151 194 195 201 256 257 258 261 262 294 295 300 301 303 vill List of Illustrations in the Text. PAGE Bark of trunk of canoe-birch, Betula papyracea . , ; : - 309 Micropholis Stowi, Huxley . , ; : ; . 841, 342, 343, 344 Skull of ? Rienodon : : s , : B d ; : . 3845 Psalidocrinus reme3i, Bather, sp. nov. (figs. 1-5) . : : ; Si Bial P. strambergensis (Remes), (figs. 6-8) . re , : : ; Wie oaizel Cluirocephalus diaphanus (Prevost) ; ; : 2 : : . B54 Rochdalia Parkeri, H. Woodw., gen. et sp. nov. . g : 5 . 355 Map of coast around Bahia Bay . : : 3 b : : . 360 Illustrations of the growth of concretions : ; é : 3 . 362 Section showing position of human skeleton at Savonas (B.C.) : . 865 Section from Black Ven to Golden Cap, Charmouth i : : . 403 Sections of Three Tiers and Green Ammonite beds : : : - 406 Detailed section of the Belemnite Marls . ; : : : : . 409 Model for a polarizing microscope - F : : 2 ; : . 447 Sketch-map of basic and ultrabasic rocks of Garabal Hill ; , . 500 Sketch-map showing the occurrence of Davainite . 3 ; : . 502 Diagram showing quartz and biotite curves . : - : . 539 Foraminifera from Eocene, Hampshire . ‘ : : : : . O57 = Price 2s, net Monit Jounal of Geology. Will WHICH IS INCORPORATED THE GHOLOGIST. j : EDILTEBD BY | HENRY ~WOODWARD, LL.D., F.R.S., F.G.S.; &c. Prorrssor J. W. GREGORY, D.Sc., E.R.S., F.G.S. Dr, GEORGE J, HINDE, F:R.S., F-G:S. Sir THOMAS H: HOLLAND, K.C.I.E., A.R.C.S.,°D.sc., F.R.S., F.G?S. “Proresson W. W. WATTS, Sc.D., M.Sc., F.R.S., Vice-Pres. GEOL. Sac Dr. ae THUR SMITH WOODWARD, F.R:S., F.L:8.. Suc. Gror Soc. is | ! : “oC e@niat. HORACE B. WOODWARD, F.R.S., F.G.S. vse St ASSISTED BY ee, JANUARY, 1913. JAN 20 19] Aaa 2 CONTENTS. @ienal Muses Ne I. ORIGINAL ARTICLES. Page REVIEWS (continued). Page | Eminent Living Geologists: Dr. The Work of Rain and Rivers. By - Eduard Suess. ee a Por- Professor T. G. Bonney, ‘Sc.D., vrai, Plate I.) 1. I IBID RID ea ed aes) ees 36. Upright Hqwisetites Eanes in Oolite A Textbook of Palzsozoology. By ‘ of Yorkshire. By Dr. T. G. Professor von Reichenbach saesuen HALLE. (Plate Tk and Text: The Structure of the Earth. By ti figure.) .. oe 3 Professor T. G. Bonney, Se.D., 5 LEDS Men. Suc 2a: Ode - Notes. on Tatavior Oolite Bade with Equisetum. By Professor PERCY Dana’s Manual of Mineralogy ae 38 Prenmen Mce, B60, 62 7 | Preh Novices: “Bexinner’s’ Guide to the Microscope—Evolution of | Physical History of Norwegian - Primitive Man—Geology of Egypt | ae ee HOLL, —, | —Croydon Nat. Hist. Society ... 38 ; North American and European Drift III. REPORTS AND PROCEEDINGS. Deposits. By R. M. DEELEY, Cambridge Philosophical Society... 40 M.Inst.C.E. (With a “Folding Geological Society of London— ~ Table and. Text-figure.) ... ... 14 November 20,1912 ... ... .... 40 “Spilite Layas hed Rdiolaniun Rocks December 4 vrs, 0.5 see nee ame a in New South Wales. By. W. December 62) si. woe ees NoEL BENSON, B.Sc. (With | Mineralogical Society— is two Sections.) ... Sil November 12,1912... 2.) teu aie he Upper Trias of ee ee _ IV. CORRESPONDENCE. Bes R. HoRwoop .....- ... 21 | A. H. Bloomfield ... 2... 0. vee 45 : i Il. REVIEWS. sverige Won os. itt Se eae ee eeetatic Position of the Monti- ee ee ey Bol euliporoids. By E.R. Cumings. : V. OBITUARY. Reviewed se D. ee es Ramsay H. Traquair, M.D., LL.D., a Diagram.)... ... Rim eisee hoy Banus. Te & ly, FGos., Sever ee LONDON: DULAU ‘& ©0., Lm, 37 SOHO SQUARE, W. = The Volume for 1912 of the GEOLOGICAL MAGAZINE is ready, price 26s. net. Cloth Cases for Binding may be had, price 1s. 6d. net. . “THE MURDOCH ‘TRUST Px m For the benefit of INDIGENT BACHELORS and WIDOWERS of Good Character, over 55 years of age, who have done ‘ something’ in the way of Promoting or Helping some branch of Science. — Donations or Pensions may be granted to persons who comply with these » conditions. For particulars apply to Messrs j. and J. TURNBULL, W.S., 58 Frederick Street, Edinburgh. Two Volumes. Royai Quarto. With Three Portraits and other Plates. - Price, in Boards, £2 10s. net. Vol. I: pp. i-cxx, 1-597. Vol. Il: pp. i-viii, ii THE SCIENTIFIC PAPERS | SIR Wi cae HERSCHEL, KNT.. GUEL PS. LL:D., Fikes. ~ INCLUDING EARLY PAPERS HITHERTO UNPUBLISHED. Collected and Edited under the direction of a Joint Committee of the Royal Society and the Royal Astronomical Society. With a Biographical Introduction compiled mainly from Unpublished uk . Material by J. L. E. Dreyer. RAY SOCIETY. Just Published. For the Sixty-eighth Year, 1911. A MONOGRAPH of the BRITISH DESMIDIACEA. Re W. WEST and Professor G. S. West. Vol. IV. -xiv-+ 194-4 66 pages, with 33 plates (xcvi-Cxxvill). Svo. Cloth 1912. 1 §s. net. (Vols. [-H1l each £1 5s. net.) f THE BRITISH TUNICATA. By the late JosHuA ALDER and the late ALBANY Hancock. Edited by JoHN Hopkinson. Vol. IIL xii+-114 + 34. pages, with 16 plates (li-Ixvi). $vo. Cloth. 1912. 12s. 6d. net. (Completing the work) Vol. 1, 128. 6d. net; Vol. Il, £1 5s. net. PALZZONTOGRAPHICAL SOCIETY. | VOLUME LXV. 4to Boards, or in separate parts. £1 5s. net. May be had separately at the prices fixed. Containing— 1. THE PLEISTOCENE MAMMALIA. —MUSTELIDAE. | With “| Title-page and Index to Vol. II. By Professor S. H. ReyNoups. Eight plates. 8s. net. ; 2. THE CARBONIFEROUS GANOID FISHES. Part I, No. 6. By Dr. R. H. TRaguair. Five plates. 55. net. 3. THE FISHES OF THE ENGLISH CHALK. Part VII. With Title-page and Index. By Dr. A. S. Woopwarp. Eight plates. $s. net. 4. THE CRETACEOUS LAMELLIBRANCHIA. Vol. II, Part VIII. By Mr. H. Woops. Four plates. 45. net. 5. THE FOSSIL SPONGES. Title-page and Index to Vol. I. By Dy, JG]. SHINDER ES Ts.net- London: DULAU & Co., Ltd., 37 Soho Square, W. ale Grou. Mac. 1913. PLATE I, PROFESSOR: E: SUESS: Reproduced by permission of Mr. W. Engelmann, Leipzig. E GHOLOGICAL MAGAZINE NEWOOSE RIS DECADE We < ¥ Obes xX: No. IL—JANUARY, 1913. ORIGINAL ARTICLES. 1.—Eminent Livine Gronogists. \ Dr. Epvarp Svzss, Late Professor of Geology (1857-1908) in the University of Vienna; For. Memb. Roy. Soc. 1894; For. Corr. Geol. Soc. 1863; For. Memb. Geol. Soc. 1877; Wollaston Medallist, 1896 ; Copley Medallist, 1903. (WITH A PORTRAIT, PLATE I.) O write an adequate notice of Professor Eduard Suess’ work would be to review the progress of Geology during nearly half a century, for in all that time he was actively engaged in helping to explain the great problems connected with the formation of the features of the Earth’s surface, and to trace accurately the principles upon which these have been brought about. Born in London August 20, 1831, Eduard Suess went with his parents to Prague in 1834, his father being engaged as a merchant in the City of London in wool-importing from Bohemia, a business which had declined owing to the abundant arrival of wool from Australia. . Suess’ first publication appeared in 1850, entitled a Sketch of the Geology of Carlsbad and its Mineral Waters. In 1851 he was appointed an Assistant in the Imperial Museum, Vienna, and in 1857 to be a professor in the University of Vienna. In 1862 Suess resigned his museum work and devoted all his leisure not occupied by his lectures in the University to paleogeographical researches, which culminated in his great work Die Antlitz der Erde, “‘The Face of the Earth’’ (1883-5 and following years), wherein he endeavoured to show the main factors and methods which have ruled in geographical evolution. After a period of more than twenty years from its appearance in Vienna, an English translation of the first volume by Miss Hertha Sollas, edited by Professor Sollas, was issued by the Clarendon Press, Oxford, in 1904; whilst the fourth volume in its English dress was published in 1909, bringing the total number of pages up to 2,233. ‘“‘The first translation of Suess’ great work, Antlits der Erde, was into French (1897-1911), an edition which, thanks to the singular erudition of its editor, Mons. EK. de Margerie, has been so enriched with footnotes as to become an invaluable work of reference for published papers in every department of the wide range of subjects of which it treats” (Geikie). In a limited notice of Professor Suess’ life-work, such as the present, it would be quite impossible to give an adequate idea of the DECADE V.—VOL. X.—NO. I. 1 2 Eminent Living Geologists—Prof. E. Suess. vast field of cosmical phenomena dealt with by him in his book. The dominant feature is the careful study of the earth-movements and foldings to which various districts have from time to time been subjected, some areas like Laurentia showing little or no disturbance since Cambrian times, the strata of that epoch lying horizontal, whereas other regions have been affected by more or less complex systems of foldings at successive epochs, the movements being influenced by buttresses of older rocks that have led to deflection and overthrusting. But we must not overlook the various services rendered to science by Professor Suess during his long and brilliant career. By his lectures in the University of Vienna he exercised a powerful influence on the work of the distinguished school of geologists whom he taught —including such men as Neumayr, Mojsisovics, Fuchs, Waagen, Penck, and many others, which shows him to have been a great master of our science. i Since 1851 a steady stream of memoirs issued by him has proved him to be a great worker in geology, while the intellectual stimulus of his writings on foreign geologists shows him to bea great thinker. Suess was never a specialist. He began work on Graptolites ; he next laid the foundations of the modern classification of the Brachiopoda and Ammonites. Alpine problems roused his interest in dynamical and structural geology, and led to studies of the Austrian and Italian earthquakes, and to his suggestion of the connexion between these and the great circle of European Tertiary volcanoes and the elevation of the Alps. Work on the complex Tertiaries of the Vienna Basin and a study of the Mediterranean littoral geology led to his researches in Faunistic Paleontology, and so prepared the way for his pupil Neumayr. Asa practical application of his geological studies in the Alps we may record that he greatly improv ed the water- supply of Vienna by bringing it from the Alps by an aqueduct 110 kilometres long. For thirty years he was a Member of the Austrian Parliament, where he did good service for science. In 1863 Professor Suess visited London, for which city (as his birthplace) he had a strong attachment. In the same year he was elected a Foreign Correspondent of the Geological Society and a Foreign Member in 1877. He was. made Copley Medallist by the Royal Society in 1903 and Wollaston Medallist by the Geological Society in 1896, and a Foreign Member of the Royal Society in 1904. Professor Suess retired from the Chair of Geology after forty-four years active service, in his 77th year. In commemorating his 80th birthday on August 20, 1911, his friend Professor Steinmann delivered a eulogium on Professor Suess’ work. He writes \— ‘‘Far beyond his University, indeed wherever the sound of the German tongue reaches, the name of Eduard Suess will to-day be remembered with the profoundest esteem by every geologist and geographer, nay, almost by every naturalist as well . . *‘Scarcely any other investigator of modern times has influenced science so lastingly and deeply as Suess. For nearly half a century he devoted his mind to the great problem of the formation of the Dr. T. G. Halle—Kquisetites Stems. 3 earth’s surface and in tracing accurately the principles upon which it was founded, Relying largely upon his ample observations and experience in former years, his work Antlitz der Erde, from ‘the Origin of the Alps’ in 1875 up to its conclusion in 1910, is a unique memorial of scientific, synthetic reasoning. In a masterly way he gathered up his facts from innumerable articles, extracting what was of value even to the smallest paragraph, whether geological or paleontological. For, to his mind, every stone might contribute to the construction of that monumental edifice which he was erecting with such careful hands . .. ‘To the congratulations of the Viennese Geological lochs offered to him on the completion of the final volume of the Antlitz he replied, ‘the merit of the chief part of the work belongs essentially to those workers who have sacrificed their vital powers to carry out those investigations which I have recorded.’ His activity as a University Professor not only benefited his class, but quickly spread beyond the walls of the lecture-room to all who would lend a willing ear to the progress of that science which he so zealously taught. To-day Suess completes the 80th year of his life. How few scientific men are permitted to retire from active work in their full health and vigour and in the enjoyment of all their faculties. He can look back upon a happy life as an investigator and a teacher; as an active citizen of Vienna, as president for many years of one of the most eminent Academies, and as an elected Member of Parhament. The son, who is on the point of taking his father’s place at the University, also gives promise of most excellent abilities.” 1 Of Professor Suess? publications the list would be too long to give, but one may mention, however, specially, the following :— “Ueber Terebratula dyphya”’: SB. k. Ak. Wiss. Wien, 1852. [His Brachiopod and Cephalopod work was continued in many papers until 1870. ] Ueber das Wesen und der Nutzen palaeontologischer Studien. Wien und Oliniiz, 1857. Der Boden der Stadt Wien... Wien, 1862. Die Entstehung der Alpen. Wien, 1875. Das Anthtz der Erde. Prag, Wien, und Leipzig, 1883-1909 ; in French, Paris, 1897-1911 ; in English, Oxford, 1904-9. 11.—Own vrricur Houvrserrres STEMS IN THE OoxnitTiIc SANDSTONE IN YORKSHIRE. By Dr. T. G. HALLE, of Stockholm.? (PLATE IL.) \TEMS of Zquisetites columnaris (Brong.) have long been known to occur in a vertical position in the sandstones of the Inferior Oolite on the Yorkshire coast. This mode of occurrence has commonly been held as proving that the stems are preserved in the position in which they once grew, having been buried in situ beneath the layers ' Die Geologie an der Wiener Universitit in den letzten 50 Jahren. Hin Blatt des Gliickwunsches und des Gedichtnisses von G. Steinmann. Aus Geologische Rundschau, ii, pp. 368-9, Leipzig, Wilhelm Engelmann, 1911, 8vo. * Communicated by Professor A. @: Nathorst, LL.D., Se.D., Ph.D., Keeper of the Department of Fossil Plants, Royal Natural History Museum, Stockholm. 4 Dr. T, G. Halle—Equisetites Stenrs of sand that accumulated on the spot. On the other hand, it has been argued that the upright position need not be primary; it might. be as readily explained if the stems are regarded as drifted and secondarily deposited on the spots where they are now found. It is well. known and has been pointed out, particularly in the discussions of the upright stems in the Coal-measures, that a drifting tree often has a tendency to sink in a vertical position, the root-end being heavier because of adhering mineral matter or from some other reason. Phillips describes, in his Geology of the Yorkshire Coast, a locality at High Whitby where upright stems of Lguisetites columnaris occur in the sandstone. He continues!: ‘‘They ... are broken off or imperfect above, and seldom reach to the upper surface of the bed; they are also broken off below, but commonly pass to the lower surface; and some of the lower joints nearest the roots are found in the subjacent bed of shale.” These facts have led, according to Phillips, to the conjecture that the plants grew in the shale ‘‘and were buried by an influx of sand and water’’. The other possibility, that the stems had been floating and deposited in vertical position, was at one time contemplated by Phillips, but he finally became convinced that ‘‘in several cases on the coast . Equiseta were prostrated and buried in abundance near to the spots where they formerly grew, and that here and there a few stems appear erect in the attitude “ot their marshy growth ”. It would appear as if the idea of a preservation in situ of the upright Hguisetites stems had been, in later years, discarded for the opposite one. Seward, who figures in his Jossil Plants a fine example of three upright stems in one piece of sandstone, expresses himself in the same work decidedly for the drift hypothesis.* The question does not appear to have received much attention lately, but it certainly deserves to be more studied both from a paleeobotanical point of view and yet more because of its bearing on the mode of deposition of the sandstone. Many instances of occurrence of upright Hquisetites stems have been noted by different geologists. It is not intended to give any review of the previous observations here; but the subject will be more fully treated by Professor P. Kendall in a paper following the present. During a visit to the Yorkshire coast, in the summer 1910, for the purpose of collecting fossil plants, I paid, on the initiative of Professor A. G. Nathorst, some attention to the upright stems of Hguisetites columnaris. The species is a very common one, and. occurs in both the shales and the sandstones of the Lower and Middle Estuarine Series. In the shales the plant is mostly found as impressions or as very flattened casts lying on the bedding-planes. In the sandstones, on the other hand, it commonly occurs as upright cylindrical casts covered with a thin dark coating which often exhibits the teeth and other features of the leaf-sheaths. The vertical stems appear to be especially common in the sandstone cliffs of the Lower Estuarine Series along the coast from Whitby to Hayburn Wyke, but they are found also in 1 J. Phillips, Illustrations to the Geology of Yorkshire, pt. i, The Yorkshire Coast, 3rd ed., p. 148, London, 1875. * A. C. Seward, Fossil Plants, vol. i, p. 72, 1897. ‘qsvoo OIIYS10 1 ‘sy0 M WNTY yeog : aYTJOO Joeyuy ‘auospurg ouLeNnysy Tomor] “sowloztyt SUIMOYS (“SuOI_) szvnwwnj00 sagosinby Jo suIE4g ‘TT WivIg | ; S161 PVA. “Tom in Oolitic Sandstone, Yorkshire. : 5 the Middle Estuarine Series, as for instance between Hayburn Wyke and Cloughton Wyke and at Scarborough. The very abundance of the upright stems is perhaps rather in favour of the in situ hypothesis. This mode of occurrence is not only frequent but appears, in many places at least, to be the rule in the sandstone. The casts are often quite crowded and convey in a striking manner the impression of a fossil Réhricht.’ A direct proof would be established, however, if rhizomes or roots of the plant were found to occur in connexion with the stems in such a manner that they must have grown into the sand. The stems are often seen to attain a con- siderable height in the rock, a couple of feet or more, and it is no doubt largely due only to the fact that the vertical surface of the sandstone cliffs generally does not quite coincide with the plane of the stems that these cannot be traced further. In some cases, however, the stems are found, when followed downwards, to disappear rather abruptly into an intercalated shaly layer, and it is then possible, as suggested by Phillips (l.c.), that their rhizomes have grown in that layer though they are usually not preserved. It is difficult, however, to establish a direct proof that such was the case. ‘Yowards the end of my stay in Yorkshire, Professor P. Kendall, of Leeds, kindly conducted me to a place where he had discovered upright Hgudsetites stems occurring abundantly in the sandstone. The locality is at the Peak Alum Works close by the railway line between Robin Hood’s Bay and Hayburn Wyke.? After a short search a few examples were found which appear to throw some light on the question. The best specimen, which is shown here in Plate II, was in a continuous wall of the cliff, but was broken out and is now in the collections of the Paleobotanical Museum at Stockholm. To the right are seen remains of two upright stems about 20cm. high and with a diameter of 2-3cm. From the lower end of one of these stems arises a lateral shoot or rhizome which continues for some distance almost horizontally at a right angle to the mother-stem, the horizontal portion being completely flattened and therefore looking very thin as seen from the side. About 25cm. from the mother stem, this horizontal shoot begins to bend gradually upwards and continues in another upright stem. At the bend there arise from the shoot some sort of appendages, three in number, which cannot be anything but roots. These run in a downward course, and the two longest can be traced for a length of 7 cm. to the base of the piece of rock. The whole specimen is such that it cannot be satis- factorily accounted for except on the supposition that it is preserved in the position of growth. A branch has grown for some distance as a creeping rhizome and has then bent upwards to form another aerial stem. The roots arising. at the bend must be taken to have grown into the sand, and it is probable that the sand had been accumulating all the time round the growing plant. I think this explanation must be admitted to be the more plausible one. ‘To account for this complex specimen as drifted and later deposited would require the assumption of such improbabilities as might well be said to approach the impossible. ‘ Reed-bed. 2 The stratigraphical conditions will be described in Professor Kendall’s paper. 6 Dr. T. G. Halle—Kquisetites Stems. Another specimen is shown, on a larger scale, in Text-fig. 1. In this case there is a cylindrical cast which is not quite vertical but somewhat obliquely ascending. ‘The cast is fairly thick, about 3°5 cm. in diameter, but only three internodes are preserved, with a length of about 10 cm. together. To two of the nodes, the one at the base and the second node above it, are attached horizontal branches, one to each node. The lower branch is very indistinct, being seen, in its flattened condition, only from the side. The upper branch lies on the upper surface of the piece of rock and can be seen from above. Its flattened cast has a breadth of 3-4 em., and it ean be traced for a distance of more than 16 cm. from the main stem to the edge of a piece of rock. Near the point of insertion of the branch there is seen what must be taken to be a root protruding obliquely downwards into the rock. Another root-like fragment is seen a little below a node near the middle of the horizontal portion. The main Fig. 1. Stems with rhizomes attached of Hqwisetites columnaris (Brong.). Lower Estuarine Sandstone, Inferior Oolite: Peak Alum Works, Yorkshire coast. interest of this specimen is in the occurrence of creeping rhizomes at different levels above each other arising from the same stem. On the lower surface of the same piece of rock there is another horizontal, flattened cast, not shown in the Figure, which is no doubt a branch from the same stem, too, though the actual connexion is not seen. The horizontal portion has a length of about 20 cm. ; then the branch bends upwards to form a new aérial stem, in the same manner as in the specimen figured in Plate IT. The features here described seem to indicate not only that the plants grew on the spot just as they are now found, but also that the accumulation of the sandstone proceeded while the plants were still growing. The sending out of creeping, root-bearing rhizomes from the upright stems at successively higher levels may be regarded as an nO. L, Kendall —Equisetites on Yorkshire Coast. 7 attempt of the plant to hold its own against the overwhelming sand. Similar cases of preservation are known from the Carboniferous formation, and have generally been regarded as proofs of an occurrence in situ and as resulting from the even balance between the growth of the plant and the silting up of its habitat. Some figures of Coal- measure plants given by Grand’Kury illustrate practically the same conditions, especially one showing a very fine group of Calamites Suckowwt from the Carboniferous of Central France ; and Grand’ Eury’s interpretation of the structure of this specimen is similar to the one applied here to the Yorkshire Hgwsetvtes. ~~ If this interpretation of the vertical Hywisetites stems is right, it will be seen to throw some light on the conditions under which the surrounding sandstone was laid down. On the spots where the EHquisetites stems grew during the accumulation of the sand, the water must have been comparatively shallow, as the tops of the stems, at least, reached above the surface. The vertical casts cannot, as a rule, be followed for more than a few feet, yet it appears highly probable that the same conditions of sedimentation prevailed during the accumulation of thick banks of sandstone. The two specimens figured here come from beds at ditferent levels in one and the same section of the sandstone, and it may be concluded with some probability that the intermediate beds were formed in the same manner too. There is no reason to regard the cases here described as mere exceptions. I am _ inclined to believe, both from the descriptions of the older writers and from my own observations, that the upright stems of Aguisetites which are so common in the sandstones as a rule have been preserved under similar conditions, in which case the sandstone too should have been deposited in a uniform manner. It would be natural to imagine that the Hyuwisetvtes erew in large, shallow fresh- or brack-water lagoons or protected estuaries with low marshy shores, and that these lagoons or estuaries were gradually becoming filled up by accumulating sand, the area being, during this process, slowly subsiding. The whole question, however, requires much more extensive observations, and it certainly deserves to be made the subject of special studies. Ii1.—Norss on tHe SrraticRapHicaL Posirion or Breps wir / EQuiseTum. By Professor PERCY FRY KENDALL, M.Sc., F.G.S. ))* NATHORST mentioned to me in 1910 the fact that the rhizomes of Hguisetum columnaris had not been observed, and I offered to show him a place where [ thought they would be found. He had not time to visit the section on that occasion, but in the following year Dr. T. G. Halle accompanied me to the exposure and agreeably to expectation the rhizomes were found within a few minutes of our arrival. ; The section is exposed at the Peak Alum Works (now Brick-works), where a splendid sequence is exhibited, extending from the Alum " C. Grand’ Hury, Flore Carbonifére du Département de la Loire et dw centre de la France, Paris, 1877, p. 15, pl. i, fig. 1. 8 Prof. P. F. Kendall—EKquisetites on Yorkshire Coast. Shales (Dactylioceras commune zone) of the Upper Lias to the over- lying Dogger Sandstone and Lower Estuarine Shales and Sandstones. The succession is as follows :— ft. in. Soil and rubble 4540 Sandstone : : : ; ; ; : 4 0 Shale . : ; 2 : 4 0 Sandy shale with boxstone concretions - 5 0 Splintered sandstone : : : : A 6 0 Raggy sandstone . : ; ; : 36 Grey and black carbonaceous shale 13 0 Raggy sandstone with many rootlets in 1 the upper part and erect ee of Hquwisetum in the lower LOWER ESTUARINE SERIES (71 ft. 2in.). 3 feet 4 6 Sandy fissile shale ait rhizomes of Equisetum and poorly preserved fronds of Williamsonia 1oe@) Grey shale without marked bedding, much resembling a Coal-measure ‘ seat-earth ’ 4 0 Shale C0) Nodular and ferruginous shale : a0 Coarse, massive, ferruginous sandstone . 2.4 i Massive sandstone pierced with many vertical roots 2.3 Compact sandstone Ave Or Fissile sandy shale 10 Black shale : : : 6 0 Dogger, very ferruginous columnar sandstone with pebbly base c 3 0 Upper Lias The Dogger Sandstone is unfossiliferous. in this section, but its lithological characters are unmistakable. The columnar jointing is in many places extremely close and well-marked, the polygonal columns in some examples being not more than two or three inches in diameter. The pebbles at the base appear to be rounded concretions, probably derived from the Upper Lias. Some show small spheroids that may be of an oolitic character and remind me of the more sparsely oolitic varieties of the Cleveland Ironstone, to which I may have mistakenly ascribed pebbles in the Dogger at Wain-Stones (see. Mr. Rastall’s paper on the Dogger, Q.J.G.8., vol. 1xi, 1905). It is interesting to note that this section i is the exposure of Dogger nearest to the Peak Fault that brings in a greatly expanded develop- ment of this division of the Towne Oolites, as well as Blea Wyke Beds and the Striatulus shales of the Upper Lias, no representative of which are found on the upthrow side of the fault. The Lower Estuarine Beds present a strong resemblance to a section of Coal-measures, and were no doubt deposited under analogous condition; the chief difference between them is in the less degree of induration of the newer series. The guisetum bed is easily recognized from the level of the railway (Scarborough and Whitby line) that passes through the quarry as the second bed of sandstone above the Dogger. Sandstone casts of Hguisetum stems in the erect position pierce the sandstone in large numbers; some fallen blocks show transverse sections on the bedding-planes every 8 or 10 inches. Stems may be traced to a length of 18 inches. The top t Prof. EH. Hull—The Norwegian Fjords. Y) ends are commonly twisted as though they had been wrenched round and bent over. A careful search in the overlying shale has so far failed to discover the much-desired fruits of the Hguisetum, but I do not despair of finding them either here or at Blea Wyke. An exactly similar bed may be observed at about the same height above the Dogger beside the footpath descending the cliff in the re-entrant angle at Blea Wyke. ‘The erect stems are contained in a strong bed of sandstone, and the flattened rhizomes occur in an underlying black shale in which many well-preserved fronds of Wailliamsonia occur. I am indebted to my friend Mr. J. T. Sewell, J.P., of Whitby, for the following note, which shows that this is not the first record of the occurrence of rhizomes of this Aguisetum:' ‘‘In one part of these cliffs was pointed out a place where a bed of sandstone, high up in the cliff, contains stems of reeds (correctly speaking these plants appear to be allied to the Equisetaceee). These are an inch or more in diameter and 2 or 38 feet long, standing upright in the sandstone, while the shales below contain the traces of their roots.” I suspect that the place alluded to is near the ‘‘Jackass Road” at Hawsker, whence the late Stephen Palmer used to obtain for me what he styled ‘‘ pieces of cain’’ (cane). 1V.—Tuer Paysicat History or roe Norweeran Fyorps. By Professor HDWARD HULL, LL.D., F.R.S., F.R.G.S. The Scandinavian Promontory.—Vhis remarkable promontory, extending for over a thousand miles from the Naze to the North Cape, is formed mainly of Archean rocks, consisting of gneiss, crystalline schists, and other metamorphic rocks, penetrated by eranite and other igneous dykes of later date. These primeval rocks are overlain throughout a portion of their extent by Cambrian and Lower Paleozoic (or Lower Silurian) beds, between which and the Archzean masses there is entire discordancy, and, as regards their respective ages, a long period of unrepresented time. The Paleozoic beds are themselves highly altered when in contact with the intrusive igneous masses, so that it is difficult to distinguish them from the more ancient masses in some districts. The older rocks are azoic, the later are fossiliferous. These combined masses constitute a truncated ridge or plateau of rocks all rising into their highest elevations? towards the Atlantic coast and breaking off abruptly in stupendous cliffs traversed by deep and narrow channels, down which streams rising in the central snowfields pour their waters into the Atlantic; while in the other direction the general surface slopes down with a more gentle declivity towards the shores of the Gulf of Bothnia and the Baltic Sea. In consequence of this conformation of the surface the river 1 Report by Sir Charles Strickland, Bart., of an Excursion by Tug-boat from Whitby to Peak of members of the Brit. Assoc. (York Meeting): Report of the Whitby Lit. and Phil. Soc., October 28, 1881. 2 Snehetta reaches 7,615 and Galdhdpiggen 8,399 feet. 10 Prof. E. Hull—The Norwegian Fjords. channels are less deep and precipitous on the eastern or Swedish side than on the western or Norwegian side of the peninsula, and the watershed approaches the western coast and is nearly conterminous with the boundary between Sweden and Norway. The special interest regarding the Norwegian fjords is concentrated on those entering the Atlantic, and is not repeated in any other part of Europe. It is here, and nowhere else, that the waters of the ocean find their way up into the very heart of the mountains, the summits of which are covered by perennial snow giving rise to the streams which enter the fjords at their upper limits; and it is in Norway, and nowhere else, that the glacial ice falls directly into the waters of the Atlantic, as is the case with the Jokel Fjord, where detached masses of ice float away on the ocean surface. It is in Norway also that we find the largest snowfield of Europe, in the Jostedalsbre, which is estimated to have an area of 580 square miles.* From what has been said it will be evident that the fjords are continuous with the rivers draining the interior snowfields and glaciers, and are to be considered as partially submerged river valleys, or, as designated by Lord Avebury, ‘‘ drowned river valleys.” * We have now to consider the process which has eventuated in the formation of these unique physical features. The Archean ridge in all probability formed part of a great primordial land barrier ranging along the Arctic Ocean in pre- Silurian times; but it is impossible to suppose that any of the streams now entering the Atlantic from Scandinavia had their origin at this period. However this may be, there can be no doubt that they drained a land surface from the Silurian period downwards throughout the whole of the vast lapse of time represented by the Mesozoic and Tertiary formations. These formations have no repre- _ sentatives in Scandinavia; and in their absence we may assume they were not deposited upon the submerged surface of the older forma- tions. It is far more probable that the peninsula remained as unsubmerged land throughout the succeeding geological periods; and throughout this vast lapse of time the rivers which drained into the ocean were eroding their channels. This at any rate is the view I find it necessary to take, as it helps us to understand how, amidst rocks of such hardness as those of Norway, channels of the depth we contemplate, both emergent and submerged, were eroded ; and have thus produced the lofty cliffs which rise from the banks of the streams and excite our admiration and astonishment; such are those of the Romsdal, the Gudvangen, and the Stalheim, rising from 2,000 to 4,000 feet on either hand from the river banks.® The Fyords.—We shall now turn our attention to some of the fjords which I have myself visited and which, with the aid of the soundings on the Admiralty Charts, excite surprise by the depths to which they 1 Encyc. Brit., 11th ed., vol. xiv. 2 The Scenery of England, 1901, p. 101. * Professor J. W. Spencer has remarked that many of the sharper peaks and precipitous cliffs owe their form to the peculiar climatic conditions of Norway— the frosts of winter and long days of summer. Prof. EH. Hull—The Norwegian Fjords. 11 descend below the surface of the ocean-water with which they are filled; they are those known as the Sogne, the Hardanger, the Volden, and the Nord. The Sogne Fjord is by far the largest of the Scandinavian sea-locks entering the Atlantic, and drains a very extensive area of mountain land. By means of the isobathic lines contoured from the sounding on the charts, one gains almost at a glance the form of the channel in which the water les. Entering from the outer ocean with a com- paratively shallow depth, the floor is found to descend rapidly down- wards till it reaches to almost 4,000 feet (665 fathoms) below the surface, a depth which it retains for a considerable distance, only becoming shallower as it approaches the upper limit of the submerged channel, where it receives the waters of the rivers descending from the interior snowfield. The maximum depth is seen to occur where the fjord is bounded on either hand by mountain masses of great extent and elevation. Similar phenomena characterize the other fjords I have named above, and need not be repeated. They all increase in depth inwards from their outiet amongst the islands which follow the coast from south to north throughout its greater extent. This form of channel evidently requires explanation, being altogether different from that of river valleys elsewhere, which necessarily, in flowing from their sources to their outlets, descend from higher to lower levels. The following are the depths to which some of thefjords reach towards the centre of their range between their outlet and their source :— : Fathoms. Feet. The Sogne (about) . ; ; é 665 4,000 ,, Hardanger 3 ‘ : : 495 2,500 », Yolden . Ne ae : : 383 2,298 », Nord : : : : ; 300 1,800 Assuming then, as I have done, that the fjords are partly sub- - merged valleys of rivers which originally entered the Atlantic or the _ Arctic Oceans, it is clear that they could only have been eroded when they were in the condition of land surfaces—as rivers never erode their channels under the waters of the ocean. As soon as rivers enter the ocean their erosive action ceases, and the force of the streams is dissipated. We must therefore suppose in the case of the Norwegian Fjords an uprise of the whole area to an extent of several thousand feet above the present level (in reference to that of the ocean) at a time when rivers flowed down them, and as such they must have had ever-deepening channels throughout their course. This is quite in accordance with the form of the river valleys of Western Europe which entered the ocean in recent Tertiary times. _ The Glaciation of Norway.—In order to account for the peculiar form of the channels it is necessary to invoke the effects of glacial snow and ice under its two heads; first, the erosive action of the ice itself, which, carrying in its mass fragments of rock, or sand, and under the pressure of thousands of feet of ice, wears down the floor 1 As I have shown in my recently published monograph, On the Sub-oceanic Physiography of the North Atlantic Ocean (EH. Stanford), 1912. 12 Prof. E. Hull—The Norwegian Fjords. of the valley as it moves seaward; or second, the power of the ice in piling up masses of moraine matters on reaching the chain of islands which follows the coast from Stavanger (lat. 59°) to the Trondhjem Fjord. This, I understand, is the more favoured explanation with the Scandinavian geologists. It is almost unnecessary to state that during the Glacial Period the whole of Norway and Sweden was covered deep with snow and ice, except where lofty peaks thrust their heads above the vast ice-field of the interior. Those who are unfamiliar with the results of glacial erosion either in past or recent times in Scandinavia, the Alps, or the British Isles, in wearing down the surfaces of the hardest rocks into hummocky forms called roches moutonnées, or covering the surfaces with grooves and striz, and transporting blocks of rock to great distances from the central snowfields and scattering them over the plains, can little realize the extent to which the glaciers of this region covered the lands and invaded the ocean bed during ‘the Great Ice Age’ of post-Tertiary times. The Norwegian ice, during a period of great elevation, descending in both directions filled the fjords, also the North Sea and, to a varying distance, the Atlantic, and meeting the ice descending from the Scottish Highlands caused it to change its course, while both together swept round the coast of Scotland and entered the Atlantic, where it was broken up and dissolved by the warm waters of.the Gulf Stream.! On the other hand, the ice descending over the plains of Sweden filled the Gulf of Bothnia and the Baltic, and invaded the plains of Russia and neighbouring countries. During a recent visit to the Baltic I was everywhere greatly impressed by the evidence of the former action of the great ice-flow in moulding the surface of the rocks, and transporting from distant sources blocks of granite or other rocks which lie on the surface or have been turned : to use for walls and buildings. It can scarcely be doubted that on the Atlantic side this ice must have eroded the surface and deepened the beds of the fjords; and this view is confirmed by the fact that (as in the case of the Sogne Fjord) the position of maximum depth of nearly 4,000 feet is just where the fjord is bounded on either hand by mountains of great extent and elevation, and where in consequence the ice would accumulate in greater mass and be most effective in eroding the bed of the glaciers. I conclude, therefore, that the ice of the Glacial Period has been an agent in deepening the channels of the valleys, but to what extent it is impossible to say, as we are not certain to what extent the piling up by moraine matter in the passage through the chain of islands has decreased the depth of the channels. We may, however, conclude that both these agencies have combined to produce the remarkable conformation of these wonderful sea-locks which give to the fjords their special interest. They are, as far as I am aware, reproduced nowhere else, ’ This remarkable movement of the ice was first recognized by Professor James Geikie, and is shown in plate vii of the Monograph of the British Isles above quoted. ProF: ‘EE, Hull—The N orwegian Fjords. 13 The Post-Glacial Subsidence.— The phenomena above described occurred during a period of high elevation, and was succeeded by one of corresponding depression, accompanied by a return of milder conditions of temperature and gradual disappearance of the ice from the fjords and lower regions of Scandinavia. In my view it was these changes of level which were the direct cause of the Glacial Epoch.! The evidences of depression of the land are apparent in many places throughout Norway in the presence of old sea-beaches, con- taining marine shells of existing species, at levels of several hundred feet above the sea-waters. According to Reusch and Hansen, these terraces occur at levels of about 200 metres (615 feet) in the Christiania and Trondhjem districts, in front of the lakes of the east country forming large plains; but are generally at lower levels, sloping distinctly from higher positions in the interior of the fjords to lower levels towards the outer coast.*, The terraces are composed of reconstructed glacial matter consisting of sand, gravel, and boulders, and the marine shells found in the glacial clays show a transition trom the cold Arctic, to that of a milder, climate of the present day. Considering that the waters of the sea must have penetrated much further inland than at the present day, and that the conditions of the glacial stage were only passing away, we may suppose that the glaciers in many places actually entered the fjords, and gave rise to icebergs, which floated into the ocean waters, and on melting scattered their contents of mud and stones over the ocean bed. In this way we may account for the spread of glacial detritus over the floor of the North Sea, filling up the submerged channels of the rivers; and owing to this it is that the river valleys are seldom traceable by means of the soundings at the present day on the Admiralty charts. _ LHpoch of Re-elevation.—We now come to the consideration of the final stage upon which the peninsula entered in order to give rise to the relations of land and water now represented with admirable correctness on our charts. Re-elevation of the land was necessary for this result, but to a far less extent than that we have previously had to deal with. It was a case of a few hundred feet against several thousand, resulting in adding large areas of land along the margin and islands bordering the continent. Sweden must have gained enormously by this elevatory process, and many islands arose where the waters previously prevailed. Tt is not my intention to discuss the question how these movements of the crust were brought about; this is a geological problem which physicists will solve in various ways. All I have to say is that it was not due to volcanic action, but is to be explained in accordance t 1 This is the view which I have endeavoured to develop in my monograph above alluded to, and I hope successfully. Judging by the results obtained by the soundings, the submerged river-channels descended to over 1,000 fathoms (6,000 feet), which gives the amount of the uplift of the land above the present level of the ocean. But for full evidence of this conclusion the reader is referred’ to the monograph itself. ° According to Professor James Geikie, quoting from Erdman, the terraces are found at levels up to 800 feet or more above the surface of the sea. (Great Ice Age, p. 388.) 14 R. M. Deeley—North American with terrestrial movements which have occurred from time to time throughout all geological history. But, in order to measure the movements, it has been necessary to recognize the level of the ocean as a datum for reference in accordance with the views of our great master Lyell. But I would only point out that however great the oscillations of the crust may appear to us living on its surface, they will appear extremely diminutive when measured by the length of the earth’s radius, which is the true standard of measurement. V.—Norra American anp Evropean Drirr Deposirs. By R. M. DEELEY, M.Inst.C.E., F.G.S. (WITH A FOLDING TABLE.) ‘J]\HE classification of the drift deposits is one which has given rise to very divergent views. One school holds that the Glacial Period was marked by increasingly severe conditions of climate followed by a somewhat regular amelioration. Another school holds that it consisted of a series of cold periods separated by warm intervals. It is not contended that in Pleistocene times the ice disappeared completely ; for itis pretty certain that on high mountain ranges, and in the Arctic and Antarctic areas, snow-fields and glaciers existed continuously. With cold conditions the ice-covered regions spread from the Polar areas and glaciers descended from the mountains, and with the return of warmer conditions the Polar glaciers and ice-fields decreased in area whilst the mountain glaciers again retreated up the valleys. The problem as to the extent to which such variations in glacial conditions occurred, and the number of times they recurred, can only be settled by a study of the Pleistocene deposits themselves. In this matter theory cannot at present help us. During recent years much work has been done which has an intimate bearing upon the question, and several geologists have given their views on the subject of the classification of the drifts. In North America, where drift deposits are especially well developed, our knowledge of them has been greatly increased by the work of Salisbury, Chamberlin, Calvin, Wiedman, Upham, Calhoun, Tarr, Gilbert, Coleman, Stone Alden, Leverett, and many others. In the European Alps and North-West Europe, Penck, Bruckner, Suess, Hess, Forel, Wahnschaffe, Keilack, French, Credner, Emil Werth, Klantzsch, Berg, and many others have done a great deal in the classification, description, and mapping. In 1895 James Geikie ' gave us a classification of the glacial deposits in which he attempted a correlation of the North American with the European deposits, whilst Frank Leverett * in 1910, in the light of more recent work, has again dealt with the question in some detail. His paper is printed in English. Leverett spent the year 1908 in Western Europe ina study which had for its aim a comparison and tentative correlation of the glacial deposits in that area with those of the United States, on the study of ' Journal of Geology, vol. iii, pp. 241-69, 1895. ; * Zeitschrift fiir Gletscherkunde, vol. iv, pp. 242-95, 321-42, 1909-10. NortH AMERICA NortH-WEST HUROPE. Three centres of ice dis 2 i : ‘ Labrador, Kewatin, and C : Ice dispersion from Scandinavia. Jerseyean Drift. FromULabra Scanian of North Germany. Boulder-clay patches deeply weathered. and fluvio-glacial drift. Nebraskan Drift. From Kew a compact blue-black boulder-c woody material. Allegany Drift. Well devel large boulders and much silt All these drifts much weathe Aftonian. Beds of sand and| Paludinenbank of Berlin. Molluses: Palu- Also soils and weathered zonesqina, Unio, Pisidium, Bythinia, Valvata, horse, elephant, mastodon, Méand Neritina. Mylodon. Freshwater shells si living in region to-day. Hypnum mosses. Woody 1 coniferous. Kansan Drift from Labrador! Tower Diluviwn. This old drift is ex- Remnants of this drift occupy t}nosed in a narrow strip outside the middle to 90 per cent having beenremoyand young drifts, from the Russian boundary The upper portion is much Wéwestward to the North Sea. Contains depth of several metres, the weatyymerous Scandinavian erratics. Is much haying been deprived of its limleyoded, and where porous much weathered. the granites are in an advanced {Some dense non-porous clays are not much weathered. Morainic ridges are noticeable in the Netherlands. Yarmouth Soil and Loess a Riadorf interglacial horizon of North peat, sand, and silt, containing wWiGerman plain. It contains an exceedingly and bones of the wood-rabbit\rich fauna of large mammalia. In Central The pre-Illinoian loess and sles there also occurs a series of inter- of this age, and contain largelolacial deposits consisting of lacustrine marls jand shells and some aquatic. |helow and loess above. The lower beds contain spruce, larch, willow, and other plants which do not live near ice-sheets. It is covered by and rests upon Boulder-clay. Illinoivan Drift irom Labrador: jyiddle Drift of North German lowland. The Tlinoian drift of the Labra, jg fresh in aspect, and although loess- is widely exposed outside the Hgoverd is now considered as of later age drift. It has not been so sever¢han the Lower Diluvium. the Kansan Drift, and was oril calcareous; but has been leache of about 6 feet. Sanganumon soiland maim Loe The loess is a wind-carried deposit, the central States consist of soil, mubrincipal mass of which seems to have been covered by loess. Contain Mle eposited during this interglacial stage. genius in some of the clays ait contains terrestrial mollusca mainly. aduncum in the peat. Loess was the great plains east of the Rock and spread by wind over the n ~plains. Kewatin. The Wisconsin Drinweathered moraine of this age stretching have suffered very little denugcross the entire breadth of the German these new-looking drifts are regjjmpire, called Grundmoranenlandschaft. this age, whether covered by | A large number of distinct mo formed during temporary advanc Wisconsm Drift from Dr Upper Diluwiwm. There are broad belts of iro —~ pum a oe Grou. Maa. 1913. a NortH AMERICAN. NORTH AMERICAN AND RBURC)PRAN BRITISH, ‘| Three centres of ice dispersion : Labrador, Kewatin, and Cordilleran. >. DRIFT DEPOSITS . (LEVERETT). ALPINE. from British Mountains and Ice dispersion ‘ Scandinavia, Jerseyean Drift. From Labrador; scattered patches deeply weathered. Nebraskan Drift. From Kewatin; is largely a compact blue-black boulder-elay with much woody material. Allegany Drift. Well developed : contains large boulders and much silt and fine sand. All these drifts much weathered. Aftonian. Beds of sand and silt with peat. Also soils and weathered zones. Mammals: horse, elephant, mastodon, Megalonyx, and Mylodon. Freshwater shells similar to those living in region to-day. Peat contains Hypnum mosses. Woody plants largely coniferous. Kansan Drift. ? The Chalky Clay of the extreme south- east of Eneland. near London, is muel 1 more weathered than the Contorted Drift an d may be older than it. There seems little question that the Boulder-clay of this region iss but a meagre remnant of a very old depcsit of an age equal to, if not greater than, the Dispersion from the Alps of France, Switzerland, Italy, and Austria. DECADE v, Von. Me Tape I, NORTH-WEST EUROPE. Ice dispersion from Scandinavia. Giinz Drift and older Deckenschotter. | Almost completely covered by later glacial deposits, but its glacial outwash, known as | the older Deckenschotter, is spread widely | over the plains bordering the Alps. It is very much weathered and in places cemented | into a conglomerate. Scanian of North Germany. Boulder-clay | 1 and fluvio-glacial drift, Saxonian. Forest Bed Series of Norfolk. (a) Complex series of marine and -Auvio- marine or estuarine deposits which sh: ow, in passing up, a change from warm tempei-ate to Arctic conditions. Contains glacial er raties. (0) Forest Bed. Plants still indigenous to Norfolk. Freshwater shells, fishes, amy hibia, reptiles, and mammals of recent sj)ecies. Extinct mammals of more southern ‘type. Giinz-mindel. Tong interval, indicated by the great amount of erosion of Giinz out- wash. Identification of interglacial deposits of this age difficult. Lignite beds of Liffe, which contain early forms of elephant and | rhinoceros, may be of this age. Paludinenbank of Berlin. Molluses: Palu- dina, Unio, Pisidium, Bythinia, Valvata, and Neritina. | } } } | ; } | aie Kansan Drift from Labrador and Kewatin. Remnants of this drift occupy the divides, 70 to90 per cent haying beenremoved by erosion. The upper portion is much weathered to a | depth of several metres, the weathered portion having been deprived of its limestone, while the granites are in an advanced state of decay. Contorted Drift. The amount of weither- ing this has experienced is very simillar to the Kansan Drift, and morainic featurles are as pronounced as those of Holland. Mindel Drift and younger Deckenschotter outwash. It is the most extensive of the glacial formations along much of the northern border of the Alps. It connects with ex- tensive deposits of glacial outwash, known as the younger Deckenschotter, which is found in broad valleys excavated through the older Deckenschotter. Lower Diluwiwn. This old drift is ex- | 2 ‘posed in a narrow strip outside the middle jand young drifts, from the Russian boundary westward to the North Sea. Contains numerous Scandinavian erraties. Is much eroded, and where porous much weathered, Some dense non-porous clays are not much weathered. Morainie ridges are noticeable in the Netherlands. Yarmouth Soil and Loess are deposits of peat, sand, and silt, containing woody material and bones of the wood-rabbit and skunk. The pre-Illinoian loess and silt deposits are of this age, and contain large numbers of land shells and some aquatic. | | | | | | Mindel—Riss. The Hottinger Breccia, near Innsbruck, whose flora calls for a warmer climate than the present, is now referred by Penck to this age. The great length of this interglacial stage is shown by the large amount of erosion the Mindel Drift and outwash experienced before the Riss Drift was laid down. Riadorf imterglacial horizon of North German plain. It contains an exceedingly rich fauna of large mammalia. In Central ‘Russia there also occurs a series of inter- glacial deposits consisting of lacustrine marls below and loess above. The lower beds contain spruce, larch, willow, and other plants which do not live near ice-sheets. Tt is covered by and rests upon Boulder-clay. ; 3 | Tllinoian Drift irom Labrador and Kewatin. __ | The Tllinoian drift of the Labrador ice-field 1s widely exposed outside the limits of later drift. It has not been so severely eroded as the Kansan Drift, and was originally very calcareous ; but has been leached to a depth of about 6 feet. Fuss Drift and high terraces of Alpine region. It differs little from the third drift of the North German foreland. In the Riss Valley the ground moraine has a gently undulating surface scarcely to be dis- tinguished from the surface of the glacial outwash. It is a coarse gravel, becoming in places cobbly and bouldery. Sangammon soil and main Loess deposits of | central States consist of soil, muck, and peat vered by loess. Contain Hlephas primi- nin the peat. Loess was derived from pee plaing east of the Rocky Mountains e d over the more eastern | genus in some of the clays and Hypnum (LO Riss-Wiirm. ‘This interglacial stage was marked by somewhat extensive erosion and lays, etc., east of the Pem ; an deposits between - aie the collection of loess upon the Riss Drift. The majority of the interglacial deposits below the later or Wiirm Drift are referred by Penck and Bruckner to this stage, but some of them may really be older. ~ Wiirm Drift and low terraces. The i hich mark the | 5 of = Middle Drift of North German lowland, JIt is fresh in aspect, and although loess- covered is now considered as of later age than the Lower Diluvium. ibnweathered moraine of ERR TRO Mie a PMA Ce The loess is a wind-carried deposit, the jorincipal mass of which seems to have been (leposited during this interglacial stage. ‘It contains terrestrial mollusca mainly. Upper Diluvium. There are broad belts of i this age stretehing | ad and European Drift Deposits. 15 which he had been engaged since 1886. In this European study about three months were spent in making the circuit of the Alps. The several drift sheets were studied under a variety of topographic conditions. Several months study in the North German lowland extended from the Russian boundary westward to the Netherlands. The limits of the last glaciation and of the next older glaciation, as well as the characteristics of each of their drifts, compared with a still older drift, exposed in recesses of the mountains along the south side of the lowland, were leading subjects of study. In Great Britain the study consisted of a few trips only along the eastern coast and brief visits to the interior. ‘This will account for the small notice taken of British Pleistocene deposits. Leverett remarks: ‘‘It would be presumptuous for one to pretend to clear up the matter of worldwide correlations of glacial deposits in a single year’s study; and no one perhaps realizes better than does the writer what a small start can be made in this brief time. A full correlation, however, may in time be reached by repeated efforts of - this sort. Even though tentative it seems worth while at this time to state what impressions and results were obtained.” In Table I are given in outline the main results arrived at by Leverett. Nos. 1, 2, 8, and 4 are the four well-marked: cold periods, whilst A, B, and C are the interglacial warmer periods. For fuller details the paper itself should be referred to. Attention may be called to the fact that both in North America and on the continent of Europe, the trend of glacial work is to support the view that there were at least four cold periods separated by long warm intervals. J. Geikie has shown that even after the Wisconsin— Witirm period there were climatic oscillations, probably of short duration, which led to considerable increases and decreases in the size of valley glaciers. This view is also held by Swiss and German geologists of note. Penck and Bruckner! show that during each of the four cold periods when the glaciers debouched upon the foreland enormous quantities of gravel and sand were thrown out over the country, filling up and obliterating all traces of many valleys. These outwash gravels were. formed when the mountain valleys were filled with great glaciers and were grinding and plucking the rocks upon which they rested. The fine rock flour found its way down the rivers to the sea. During each interglacial stage, when the glaciers had almost wholly melted away, the rivers cut deep valleys through the outwash gravels. Thus valleys were eroded during warm periods and again filled by outwash gravels during cold periods. There is very good evidence that during the four main glacial periods the precipitation of moisture was about the same as that during the warm periods, and that the development of the glaciers was almost entirely due to fall of temperature. We, therefore, see that during the glacial periods the rivers were so charged with debris that they could not transport it at normal gradients, and, as a result, they deposited pans of outwash material. With the disappearance of the great glaciers great erosion ceased, and 1 Die Alpen Ciszeitalter. R. M. Deeley— Drift Deposits. 16 "Svat UI SE5V PoYVULI]S9 MOYS BSSOsqY “oUl[-MOUS JO JYSIOY UT SUONBIABA MOYS soyvUIPIC “UBET[OYD PUB ‘UBITEYSNOP, “UVIAYNOY ‘UBIUETVpSsByT ‘OIPTOON : UBUT Fo sosRAS arNgyNO *‘POpuUly—-ZUNy) = "WH ‘SSnJ-opurpy, “WIN AA -SSNT= "MAY :Spoleg [eVrovps1ejuy ‘TUM @ ‘zgtuqosy 6 ‘uneg p :sesvyg ‘zuny pur ‘fopurp ‘Sst ‘ULIMA\ : Spoltog [vIORpH ‘T ‘OIL Sivah0000k 000009 000008 00000-6 o00co¢ 900002 000001 0 = ae) Le Se Ge En De Se OOSI- PRU ee SS1Ay - J2pUIW UDNIOYI > — FOSSIL BEADS (?) FROM THE GRAVEL OF BEDFORDSHIRE. ARE THEY EVIDENCE OF HUMAN WORKMANSHIP ? Srr,—As I was searching in a gravel-pit some few weeks ago one of the workmen brought me some very curious beads, which I enclose to you. They lay in various positions in the gravel, and were not all in one place, but scattered about in ditferent parts of the pit, and they varied in size from that of a large marble to that of a pea. The supposition is that they are sponges, but possibly some of them may have been artificially fashioned and drilled for stringing. Advantage may have been taken in the case of the others of a natural perforation formed by the decay of the nucleus round which the sponge was formed, and the hole enlarged by one of those flint-borers which are often found, to admit of stringing on a sinew or a strip of hide. I am told that Paleolithic implements have been found in this pit, though I was not so fortunate as to find any. May I not pertinently ask, does not the occurrence of these beads point to a higher state of development in Paleolithic man than is generally conceded ? Indications are not wanting which strongly support this view. Witness the cave-paintings of Altamira in Spain, and the occurrence of highly worked Paleolithic implements in caves of Aurignacian age in France, and lately of similar flints at Duston, Northants. While on this subject may I ask why there should not have been in Paleolithic times men of different stages of development living in different parts of the world as at the present day? The tendency has been to class all these ancient races as under the same degree and state of development. It is probably in southern regions where the earliest traces of the higher-developed Paleolithic man are to be found, climatie conditions in the north in those early times being less favourable to their development, if not precluding their existence altogether. I may say Correspondence—Fossil Beads. 139 that the locality is Willington, Bedfordshire, and the formation river-gravel. J. T. Bawnron. KINGSTON RECTORY, CAMBRIDGE. January 18, 1913. P.S.—The Rev. O. Fisher M.A., F.G.S., and Professor J. E. Marr, Se.D., F.R.S., who have seen the beads, both support the view of their having been used as personal ornaments. They are often, though by no means always, perforated naturally. There is strong reason for supposing they have been used as beads.—J. T. B. Nore spy THE EDITOR ON THE SO-CALLED ‘ Fosstn Buraps’. In reply to Mr. J. T. Banton’s letter it may interest some of our readers to learn that the so-called fossil beads were figured by Dr. G. A. Mantell in his Geology of Sussex in 1822 from the Chalk near Brighton ; and in 1829 by Professor J. Phillips in Geology of Yorkshire. In 1833 Samuel Woodward in his Outlines of the Geology of Norfolk figured several examples from Norwich and from Holt as Millepora globularis (now known as Porosphera globularis, Phillips, sp., a small globular species of Calcisponge from the Chalk of England and the Continent). Their history is very extensive, and has been most carefully set forth by Dr. G. J. Hinde, F.R.S. (see Journ. Roy. Micro. Soc., 1904, pt. 1, pp. I 25, pls. 1 and 11), who describes and figures six species. In Mr. James Wyatt’s paper in the Geologist (vol. v, pp. 233-6, 1862) the writer says he first became acquainted with these objects about fifteen years earlier (1847) when uncovering some Anglo-Saxon remains in the Kempston gravel-pit, near Bedford, when several round stones perforated were met with; he adds, “‘ so strongly was I impressed at the time that they were the personal ornaments of the ancient chieftain just exhumed that I actually presented them to the Archeological Society as Saxon beads . Subsequent examination of the Drift gravels convinced me that the balls were of an earlier period than the Anglo-Saxon, whether works of art or natural productions. They are described by naturalists as specimens of the Chalk fossil Cosccnopora globularis, but the question is, how did they become perforated ?”? Mr. Wyatt, after having examined a great number of specimens, concludes the perforation in these small globular bodies to be artzficial. In this opinion he was supported by Dr. Rigollot,! who wrote that ‘‘les petites boules avaient servi a former des colliers 4 l’usage des peuple sauvages”’; but subsequently a strong objection was taken to this opinion by M. Albert Gaudry, who? denies that there is any evidence for the assertion that these are works of art, and asserts that they are found in the Chalk perforated in the same manner as those specimens found in the Drift. * See account of Dr. Rigollot’s observations (Mémoire sur les instruments en silex, etc., p. 16, Amiens, 1854). See also Lyell’s Antiquity of Man, 4th ed., 1873, pp. 165-6, fig. 22. F Trans. Inst. France. 140 Correspondence—Fossil Beads. In the same volume of the Geologist (pp. 285-6) Professor T. Rupert Jones points out that these bodies, so common in the gravel of Chalk districts, particularly in Bedfordshire and at St. Acheul, have all been, originally, derived from the Chalk in which they are abundantly found, either perforated or solid, or with a more or less shallow hole in their substance. They occur in the Chalk itself; on the beaches under Chalk cliffs (as at Ramsgate, etc.) and in drift beds, the materials of which have been furnished by the Chalk, and in the decomposed chalk along the bottom slopes of. the North and South Downs. ‘““The concavity of the typical variety (Porosphera globularis) becomes in many of the globular forms a small cavity, a hole, or even a neat cylindrical perforation. The roundness of the specimens and their holes and tubular cavities,’ says Professor Rupert Jones, ‘“‘ appear to have suggested to the old Flint-folk of the Valley of the Somme, that they might be used for beads; such perforated forms are frequent in the gravel that yields the flint axes. I may add” (he says) ‘‘that the imperforate forms occur in the gravels just as 5 Fic. 1. Porosphera globularis, Phillips, reproduced by the author’s kind permission from pl. i of paper by Dr. G. J. Hinde, F.R.S. (Journ. Roy. Micro. Soc., 1904, p. 1-25). much as the perforate. Also that the perforation of the non-drifted specimens in the Chalk is often just as smooth and straight as if artificial ; the interior surface is not worn, however, but consists of the natural structure of the organism.”’ (April 22, 1862.) Dr. G. J. Hinde, F.R.S., in his valuable memoir on Porosphera — (Journ. Roy. Micro. Soc., 1904, pp. 1-25, pls. 1 and ii) says that Dr. A. W. Rowe, F.G.S., in his researches on the fossils from the different zones of the Chalk on the east and south coasts of England has met with many hundred examples of Porosphera which he had placed in Dr. Hinde’s hands for examination. This little sponge is common in the chalk cliffs of Yorkshire, Kent, Sussex, Isle of Wight, Dorset, and South Devon. Dr. Hinde writes: ‘‘I may mention that within the limits of a moderately-sized garden situated on the slope of a chalk down at Croydon, Surrey, I have during the last sixteen years picked from the surface-soil 632 specimens of different forms of Porosphera which have all been derived by slow weathering from the underlying Chalk.”’ Correspondence—Fossil Beads. Po eal Out of the large series of 2,902 specimens of Porosphera examined and determined by Dr. Hinde, about two-thirds, he says, were obtained by Dr. A. W. Rowe, F.G.S., whose researches on the fossils of the different zones of the Chalk of England have become a classical work to all students of Cretaceous geology. In Dr. Hinde’s opinion we find only 3 examples named Porosphera Woodwardi, Carter, sp., from the Lower Chalk (Cenomanien) of Dover and the Dorset coast. 109 were obtained from localities in the Middle Chalk (Turonian), 99 of which are referred to P. globularis, 3 to P. patelliformis, and 7 to P. arrecta. But the majority of specimens, 2,770, were obtained from the Upper Chalk (Senonian), which yielded 2,244 examples of P. globularis, 257 of P. nuciformis, 149 referred to P. pileolus, 94 to P. patelliformis, 7 to P. arrecta, and 19 to ‘irregular forms of Porosphera’’; while of zones unknown, 14 are referred by Dr. Hinde to P. glubularis, 1 to P. prileolus, 4 to P. patelliformis, and 1 an irregular form. In all, 2,902 were examined and determined by him, of which 2,357 are referred to P. globularis and 545 to the six other species. If we except the Lower Chalk, P. globularis oceurs throughout the Middle and Upper Chalk, and is very abundant at Dover; in Devon, Seaford and Newhaven, Croydon, Margate, Brighton, Sewerby, and on the Dorset coast. These localities do Fig. 2. Porosphera globularis, Phillips, a small bead-like fossil sponge, derived from the Chalk, and found abundantly in the old river-valley gravels of Bedfordshire. The above figures are reproduced from an article by Mr. James Wyatt, F.G.S. (see the Geologist, vol. v, pp. 233-5, 1862). not include the vast number met with in the Bedfordshire gravels and elsewhere derived from the Chalk, whilst it is abundant in the gravels at Amiens and Abbeville in France, and is present almost everywhere in the Chalk of Middle and Northern Europe. Dr. Hinde adds: ‘‘In form these sponges are generally rounded like peas or marbles, but are sometimes oval, loaf- or cushion-shaped, without any distinctive base; they are mostly free and unattached, but in many cases they grew round foreign bodies, which have been incapable of fossilisation, and these sponges now exhibit cylindrical hollow tubes which extend partly or entirely through them [see 1, Fig. 1}. Generally increase of growth is uniform over the surface, but in some instances fresh layers are formed so as only to cover portions of the surface at once [see 4, Fig. 1]. Small specimens are found of about lmm., the larger forms range to 34mm. in diameter.” (Op. cit., ids U@s)) In another place (p. 11) Dr. Hinde says: ‘‘ Numerous specimens of P. globularis, and also of P. nuciformis, are penetrated by cylindrical 142 Correspondence—Fossil Beads. tubes, some of which extend quite through, so that the specimen becomes a natural bead, whilst others reach only to the central portion of the fossil or beyond to near the opposite side, but without passing through it completely [see 1, Fig. 1]. The tubes generally pass straight through the centres of the rounded forms, but they are not definitely orientated in the cushion- or pear-shaped fossils through which they extend either longitudinally, transversely or obliquely. Out of 1799 specimens of P. globularis . . . 321 or about 18 per cent were perforated; 147 being completely perforated, or natural beads, whilst 174 were partially perforated. Of P. nuczformis there were tubes in 32, 6 of which extended through, whilst 26 only reached to varying depths in the fossils.” In a letter just received from Dr. Hinde, the writer says: ‘‘I do not doubt in the least that the perforations are natural and I think it is a mistake to suppose that they have been artificially produced. Numbers of specimens from the surface soil of my garden still have the holes solidly infilled with chalk and I have had to pick out the material with a needle, so that in these examples, at least, the holes were present when the fossil was imbedded in the chalk ooze of the sea-bottom.” He adds: ‘‘Mr. G. Crick gave me, some years ago, numerous specimens of P. globularis from the Bedfordshire gravels, in which they are so common as to serve as playthings for children! These eravel-specimens have their holes wider and larger as a rule than those obtained direct from the Chalk’’—having been waterworn. ‘‘T quite agree with you that there is no definite evidence that they were used as beads by prehistoric man, although they might have been so used.” Referring to the abundance, origin, and wide distribution of this little sponge in the river-valley gravels of the Ouse, Mr. Horace B. Woodward, F.R.S., writes me: ‘‘'The Porosphera may well have come from the Chalk of Bedfordshire, which rises up in the Dunstable and Luton Downs—a continuation of the Chiltern Hills.. It may also quite possibly have come indirectly by way of the ‘Chalky Boulder-clay ’, which covers large tracts of the Bedford Vale resting on Oxford Clay, bordering the Valley Gravels. The gravel is largely made up of chalk-flints, but it also contains a good deal of Oolitic limestone, derived from the Great Oolite, etc., or from the Boulder-clay.” From the foregoing observations I think we may conclude— 1. That the cylindrical perforations, so commonly present in specimens of Porosphera, are natural, not artificial, being met with as frequently in specimens obtained directly from the Chalk as in those met with in the Valley Gravel. 2. That their great abundance, scattered promiscuously through the gravel of Bedfordshire and elsewhere, affords no evidence in favour of their having been adopted as ornaments by prehistoric man. 3. That there is no case known or recorded in which they have been so used. On the other hand, the shells of Wassa neritea and teeth of stag bored for suspension probably as a head-dress or necklace were found Correspondence—Dr. H. J. Johuston-Lavis. 143, with the skeleton of a prehistoric man, probably of Neolithic age, in a cave at Mentone.’ There are some interesting notes by Dr. Robert Brown, F.L.S., F.R.G.S. (1868), and Mr. Alexander C. Anderson (Vancouver Island) on shells used by prehistoric people and modern North American Indians as ornaments (see Reliquie Aquitanice, by HK. Lartet and H. Christy, edited by T. Rupert Jones, 1865-75, p. 296). In the same work also at p. 70 a shell-necklace from Cro-Magnon Cave is figured on B, pl. xi, composed of Littorina littorea, Purpura lapillus, Turritella communis, etc. In the Cavern of Bruniquel explored by the Vicomte de Lastic in the Valley of the Aveyron fossz/ shells were found perforated, which had evidently been used as personal ornaments (see op. cit., p. 70); the collection is now preserved in the British Museum. H. W. SEA-WATER AND CRITICAL TEMPERATURES. Sim,—How very true the parable of the moat and the beam is, and what a good example thereof is afforded by the letter of Mr. A. R. Hunt in your last number! He accuses his fellow-workers in geology, after a disquisition on the knowledge of foreign languages, of neglecting the researches of Daubrée and other workers abroad. Yet, although he has written on the subject of sea-water in volcanic and metamorphic action, he has apparently never read some dozen or more papers of mine on that subject, written years before (1892-4), though his own countryman. I have distinctly shown that the critical point of water has nothing whatever to do with the question, and that we have to consider the physical conditions of the gas H, O im solution, under varying pressure in fused silicates and oxides. I have urged the alkalinization of magmas by the assimilation of the alkaline salts in sea and other water, and accompanied by the liberation of the acid radicles in the form of the enormous emanations at volcanic vents. Furthermore, as mineralizers and fluxes, I have mentioned over and over again saline substances as being great agents in metamorphism. I laid down the fundamental principles of eruptive activity, which have never been controverted or controvertible because they are demonstrated and illustrated in all volcanic regions, principally by the nature and characters of the fragmentary ejecta of volcanoes. Strangely enough, geologists and petrographers steadily and uniformly ignore the invaluable lessons taught by a study of fragmentary ejecta, while they cover thousands of pages with hypothetical, chemical groupings of massive rocks, ornamented by the most astoundingly complicated nomenclature, which, in the end, adds naught to our knowledge. Almost equally uselessly, they make elaborate calculations of percentages of different hypothetical felspars, and are blind to other structures that really record the vicissitudes between the primitive, purely vitreous paste and the consolidated rock. 1 See Comptes Rendus, No. 26, p. 1597, June, 1872; also GEOL. MaAG., Vol. IX, pp. 272-4, 1872 (with a figure) ; also op. cit., p. 368, and article by Professor John Morris, Pop. Sci. Review, July, 1872. 144 Miscellaneous— Antarctic Expedition. If Mr. A. R. Hunt will read my papers, he will find that a very full use is made of the experimental geology of foreign workers, where they explain the genesis of minerals or rock structure in igneous and metamorphic rocks. I rather fear that the experiment of the piece of granite, suggested by Mr. Hunt, is not a fair reproduction of natural conditions. We must not expect the packing of any rock at great depths to allow fissures. The flow of solids under such conditions of high pressure and high temperature will reduce al/ rock substances to some advanced degree of viscosity, and allow the ‘écoulement des solides’, which, even in superficial rocks such as are found in mines, is known as ‘creep’. The transmission of water to igneous foci is really a process of hydration and solution (and not percolation), too long to discuss in this letter. I shall be pleased to supply Mr. Hunt with a list of my papers to which he may refer. H. J. Joansron-Lavis. BEAULIEU-SUR-MER. February 12, 1913. MIiSCHILUMAN HOUS. Anrarcric EXPEDITION. In Memoriam. It is with deep regret that we briefly record the deaths from exposure and starvation, after accomplishing their mission to reach the South Pole, of the heroic five, Captain Robert Falcon Scott, Captain L. E. G. Oates, Dr. E. A. Wilson, Lieut. H. R. Bowers, and Petty Officer Edgar Evans. They had arrived within eleven miles of their stores, but a blizzard which lasted nine days and nights over- whelmed them. It is but poor comfort to know that the relief party found and buried the unfortunate explorers and recovered all their records and geological specimens. Croypon’s ‘ Wor Warers’.—Croydon’s mysterious ‘woe waters’, the Bourne flow, made its appearance yesterday in Caterham Valley. In a few weeks the tiny stream on Welford’s Farm, Whyteleafe, will have become a rushing brook, overflowing its banks for miles down the valley to Purley. Originally each visitation was regarded as foretelling war, plague, or famine. Mr. Baldwin Latham, M. Inst.C.E., who has studied each flow since 1866, attributes it to the uprising of the ground-water (plane of saturation) in the Chalk, after periods of much rain. He fixed the flow this year for February 3.—In part from the Daily Telegraph, February 1, 1913. Erratum.—In a review of a memoir on ‘‘ The Sedimentary Deposition of Oil”, by Dr. Murray Stuart, F.G.S., Professor of Geology in Presidency College, Madras, the author’s name was by an oversight printed ‘‘Stewart” (see Gror. Mae., December, 1912, pp. 570-1, and in the Index, p. 583). Please correct to ‘‘ Srvarr”’. The Editor expresses his deep regret. eee PUBLISHED. Ho 8vo. pp. 116. With 3 Blatee and large Coloured Zonal ie eee Map. 10s. 6d. net. THE STRATIGRAPHY THE CHALK OF HANTS - WITH MAP ann PALAZONTOLOGICAL NOTES. BY . R. M. BRYDONE, F.G.S. BRITISH MUSEUM (NATURAL HISTORY) NEW PUBLICATIONS. Catalogue of the Collection of Birds’ Eggs in the British Museum (Natural History). Vol. V. Carinate (Passeri- formes completed). By W. R. Ocinvie-GRant. 8vo. pp. xxii, 547, with 22 coloured plates. Cloth. £2 Ts, 6d. Catalogue of the Cheetopoda in the Eritish Museum (Natural History). A. Polychxta.—Part I: Arenicolide. By J. H. ASHwortH. Roy. 8vo. With 15 plates. Cloth. 27s. 6d. MILLER (G.S.). Catalogue of the Moms of Western Europe (Europe exclusive of Russia) in the Collection of the British Museum. 68vo. pp. 1034, with illustrations. Cloth. 26s. History of the Collections contained in the Natural History Departments. Vol. II: Appendix, Zoology, 1856 to 1895. By Dr. A. GuNTHER. 8yo. pp. 118. Cloth. 5s. WOODWARD (Horace B.). The Geology of Soils and Substrata. With Special Reference to Agriculture, Estates, and Sanitation. London, 1912. Cr, 8v0. pp. 382. (Ss, 60.net, DULAU & CO., LTD., 37 SOHO SQUARE. LONDON, W. aes Fat Se Fh Node — r BRITISH PETROGRAPHY. With Special Reference to the Igneous Rocks. By J. J. Harris Teall. 1888. Roy. 8vo. 458 pp. of text, with 47 plates, some coloured, bound in cloth extra, gilt top. £3 3s. net. CLIMATIC CHANGES SINCE THE LAST ICE AGE. A Collection of Papers read before ‘the Committee of the Eleventh International Geologica/ Congress at Stockholm, 1970. 4to. Sewed. £1 net. THE IRON ORE RESOURCES OF THE WORLD. 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W. WATTS, Sc.D., M.Sc., F.R.S., Vick-Pres. GEOL. Soc. Dr. ARTHUR SMITH WOODWARD, F.R.S., F.L.S., Src. Grou. Soc. HORACE B. WOODWARD, F.R.S., F.G.S. apsonian Institge~. APRIL, 1913. /<* | 4 APRLO 1918 CF @ NG IN a ay ’ ? February 26, 1913.—Dr. Aubrey Strahan, F.R.S., President, in the Chair. The following communications were read :— 1. ‘The Geology of Bardsey Island (Carnarvonshire).” By Charles Alfred Matley, D.Sc., F.G.S.; with an Appendix on the Petrography by John Smith Flett, M.A., D.Se., F.G.S. Bardsey, an island a mile and three-quarters long, lies off the promontory of the Lleyn (Western Carnarvonshire), and forms the isolated extremity of the strip of pre-Cambrian rocks that borders the western coast of the Lleyn from Nevin south-westwards. The rocks are principally gritty schistose slates, with many thin and some thick bands of grit, quartzite, and limestone; and they contain an horizon of variolitic lava and tufaceous shale, which indicates that a volcanic episode took place during their formation. Sills of albite-diabase also occur, as well as one or more sills of a crushed granite. The rocks have been subjected to intense earth-pressure acting mainly from the north-west, and are mostly in a cataclastic condition, the harder rocks being almost always torn up into lenticles. The beds are shown to be arranged on the whole in a number of isoclinal folds, complicated by overthrusting, shearing, and _ brecciation. Stages in the formation of crush conglomerates are described. From the nature of the brecciation and the comparatively small amount of © mineral alteration that the beds have undergone, it is inferred that Reports & Proceedings—Geological Socrety of London. 189 the load of superincumbent rock at the time of the principal earth- movements was not great. The rocks are correlated with the lower portion of the Llanbadrig Beds and with the Llanfair y’nghornwy Beds of Anglesey, and they agree also with their Anglesey representatives in the manner in which they have been affected by earth-movement. ‘Some post-movement dykes of olivine-dolerite occur, with a north- west to south-east trend. They are probably of Tertiary age. Glacial striae and boulders indicate that the island was invaded by a portion of the Irish Sea ice-sheet, which, after crossing Anglesey to the west of Red Wharf Bay in a south-westerly direction, was deflected in Carnarvon Bay and traversed Bardsey in a south-easterly direction. This direction is tentatively attributed to the pressure of ice radiating from Ireland. There are doubtful indications of a post-Glacial raised beach at 18 to 20 feet O.D. - In an Appendix Dr. J. 8S. Flett describes the petrographical characters of the granites, the pillow-lavas and their tuffs, and the diabases. 2. ‘The Loch Awe Syncline (Argyllshire).” By Edward Battersby Bailey, B.A., F.G.S. Mr. J. B. Hill’s classification of the sedimentary schists of the district, into the Loch Awe Group above, and the Ardrishaig Group below, is accepted. So also is his reading of the Loch Awe Syncline. This syncline is a comparatively shallow trough, with well-marked fan-structure due to small-scale isoclinal folding, in which the limbs of the folds are vertical along the axial belt of the syncline, and inclined outwards on either side. _ There are, however, two modifications of Mr. Hill’s original interpretation, both of them already dealt with, in part, by Dr. B. N. Peach and the author in the Geological Survey memoir describing the southernmost portion of the region (Sheet 28). One of the proposed alterations is concerned with the numberless igneous rocks folded along with the sedimentary schists. Many of these are obvious intrusions; but some, as Dr. Peach showed in 1903, are certainly lavas. In the present paper Dr. Peach’s volcanic zone is traced throughout the whole district, where it maintains a constant horizon in the Loch Awe Group. This brings us to the second sugeested modification, affecting, as it does, details of the strati- graphy of the Loch Awe Group, for which the following sequence is proposed :— Loch Avich Green Slates and Grits (volcanic rocks in the lower part). Tayvallich Black Slates and Limestones (volcanic rocks throughout) Crinan Grits and Quartzites. | Shira Limestone, constituting a passage-zone down into the Ardrishaig Phyllites. Attention is drawn to evidence, already published, that the order of superposition of the sediments in the Loch Awe Syncline corresponds with the original order of sedimentary superposition. Finally, a recent suggestion of Mr. Hill’s is adopted, in which he correlates the extremely low grade of metamorphism of the rocks 190 Correspondence—A. kh. Hunt. of the central part of the Loch Awe Syncline with their high structural position. The hypothesis is that these rocks were not deeply covered during their metamorphism, and accordingly were never raised to any very high temperature. CORRESPONDENCE. ———— > CRITICAL TEMPERATURES AND CRITICAL CONTROVERSY. Srr,—Referring to Dr. Johnston-Lavis’ letter, I am sorry if I have failed to do him justice. I have a list of eighty of his papers to 1890, none, however, bearing on critical temperatures. If he will send me references to any subsequent ones bearing on the action of superheated water I shall be obliged. And now I must throw myself on your Editorial leniency and that of your readers. On the day I received the proofs of the article which appears this month I suffered a serious nervous collapse, and am under strict orders to spare myself in every way, and this just at a moment when the Survey Memoir of Dartmoor makes it incumbent on me to review nearly thirty years of observation of that district; and Mr. Jukes-Browne’s papers on ‘‘The Making of Torbay” and on ‘‘The Torquay Limestones” do the same for about forty years’ reflections on the raised beaches and general geology of that district ! In addition to this there is a good deal that wants saying about Kent’s Cavern. I am very sorry to have broached subjects in your columns which I cannot for the moment now defend, in critical controversy, but I will try to meet any objections, or yield to them, if possible later on. If not in this Magazine, then somewhere else. A. R. Hunt. SouTHWOOD, TORQUAY. March 7, 19138. PREHISTORIC BEADS. Srr,—As a supplement to my letter in the Gror. Mac. for March, p- 138, and your reply thereto, pp. 1389-48, I send you the following quotation from Sir Charles Lyell’s Antiquity of Man (4th edition, p. 165). He writes as follows: ‘In the gravel-pits of St. Acheul, and a (4 b a, b, Porosphera globularis, Phillips, copied from Lyell’s Antiquity of Man, 4th ed., p. 165, fig. 22, 1873; c, part of same magnified. in some others near Amiens, small round bodies, having a tubular cavity in the centre, occur. They are well known as fossils of the White Chalk. Dr. Rigollot suggested that they might have been strung Obituary—Russell Frost Gwinnell. 191 together as beads, and he supposed the hole in the centre to have been artificial. Some of these round bodies are found entire in the chalk and in the gravel, others have a hole passing through them, and sometimes one or two holes penetrating some way in from the surface, and not extending to the other side. Others, like 6 in Figure, have a large cavity, which has a very artificial aspect. It is impossible to decide whether they have or have not served as personal ornaments, recommended by their globular form, lightness, and by being less destructible than ordinary chalk. Granting that there were natural cavities in the axis of some of them, it does not follow that these may not have been taken advantage of for stringing them as beads, while others may have been artificially bored through. Dr. Rigollot’s argument in favour of them having been used as necklaces or bracelets appears to me a sound one. He says he often found small heaps or groups of them in one place, all perforated, just as if, when swept into the river’s bed by a flood, the bond or string which had united them together remained unbroken.!”’ J. T. Banron. KINGSTON RECTORY, CAMBRIDGE. OBITUARY - RUSSELL FROST GWINNELL, B.Sc., Assoc. R.C.Scr., F.G.S. BorRN APRIL 21, 1880. DiED MARCH 15, 1913. WE deeply regret to record the death of Mr. R. F. Gwinnell, at the early age of 33 years. He had been for some years Demonstrator in Geology under Professor W. W. Watts, F.R.S., in the Imperial College of Science and Technology, South Kensington, and also an Examiner in Geology to the Board of Education. Mr. R. F. Gwinnell was a bachelor living at home with his parents, his father, Mr. Wintour ~F. Gwinnell, B.Sc., F.G.S., 34 Barrowgate Road, Chiswick, W., being a well-known University ‘coach’ and an accomplished science teacher of long standing. MALCOLM POIGNAND. Born 1850. DIED MARCH 2, 1913. We regret to record the death on March 2, in his 63rd year, of Dr. Malcolm Poignand, of the Beeches, Walsham-le- Willows, Suffolk. He was a member of the Geologists’ Association, and took an active interest in geology, having collected many fossils from the Jurassic strata of Dorset and other formations, some of his specimens being referred to in the Proceedings of the Association (vol. ix, p. 204). He received his medical education at St. Bartholomew’s Hospital, and subsequently at Aberdeen University, where he took the degree of M.D. in 1878. “*1 Rigollot, Mémoire sur des Instruments en Silex, etc., p. 16. Amiens, 1854.”’ 192. Miscellaneous—Thomas Pennant Collection of Fossils. MISCHLUIANHOUS.- OAPs Ture Tuomas Pennant CoL.ecrion oF Fossitzs. Some published notices have recently appeared calling attention to the natural history collections of Thomas Pennant, formed a century and a half ago, which have been generously presented to the British Museum by the Right Honourable the Earl and. Countess of Denbigh, of Downing, Flintshire, Pennant’s birthplace and home, where the collections have lain since his death in 1798. As no mention has been made of the fossils, which form an important part of this gift, it seems necessary to make a statement on the subject. These fossils comprise upwards of a thousand specimens, including the remains of Vertebrates, Mollusca, Brachiopods, Crustacea, Corals, and other groups of organisms from various geological horizons of both British and foreign localities. Many of the specimens bear a number having reference to a manuscript catalogue where brief descriptions are given. The main title of this volume is somewhat quaint, and reads as follows: Reliquie Diluwiane, or a Catalogue of such Bodies as were deposited in the Earth by the Deluge. On the back is printed in gilt letters ‘‘ Extraneous Fossils, vol. 3”. A few of the fossils are distinctly interesting from the fact that they have been either figured or mentioned in literature; and particularly is this the case in connexion with three small Wenlock Limestone corals from the Coalbrookdale area of Shropshire. These were described and figured by Pennant in one of his earliest published papers of the Philosophical Transactions (Royal Society), vol. xlix, pt, qu, pl. xv, figs. 1, 3, 4, pp. 518, 514, 1757, entitled ‘‘ An Account of some Fungite. and other Coralloid Fossil Bodies’’; such specimens being now recognized under the genera Lavosites and Actinocystis. There is also a Mammoth tooth which is referred to in his Synopsis of Quadrupeds, p. 90 (1771), as having been found in a bed of gravel beneath a thick limestone, ‘‘at the depth of 42 yards in a lead-mine in Flintshire.” Thomas Pennant (1726-98) was a naturalist of considerable reputation, having been a contemporary and correspondent of Linneus, and a close friend of Gilbert White, whose letters forming Zhe Natural History of Selborne were mostly addressed to ‘‘Thomas Pennant, Esq.”? He was the author of numerous works on natural history, such as The British Zoology (1766), Genera of Birds (1778), History of Quadrupeds (1781), etc., some of which reached several editions. It may be of interest to add that a small selected series of these fossils is now exhibited in one of the Museum table-cases of the Geological Department, in company with the Hans Sloane, the Brander, and other historical collections ; the remainder are arranged in the cabinet drawers beneath. 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A Descriptive Catalogue of the Marine Reptiles of the Oxford Clay, based on the Leeds Collection in the British Museum (Natural History). Part Il. pp. 230; 78 text- figures and 14 plates. 4to. Cloth. £1 5s. Part I, 1910. 4to. pp. 228; 94 text-figures and 11 plates. Cloth. £1 ds. Svo. Cloth, £1 1s. | Observations on the West of England Mining Region. Being an account of the Mineral Deposits and Economic Geology of the Region, and forming Vol. XIV of the Transactions of the Royal Geological Society of Cornwall. By: l-COLEINS, F.G.S. BRITISH PETROGRAPHY. With Special Reference to the Igneous Rocks. By J. J. Harris Teall. 1888. Roy. 8vo. 458 pp. of text, with 47 plates, some coloured, bound in cloth extra, gilt top. 43 35. net. DULAU & CO., LTD., 37 SOHO SQUARE, LONDON, W. THE LAST ICE AGE. A Collection of Papers read before the Committee of the Eleventh International Geologica/ Congress at Stockholm, 1910. 4to. Sewed. £1 net. CLIMATIC CHANGES SINCE | THE IRON ORE RESOURCES OF THE WORLD. 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WATTS, Sc.D., M.Sc., F.R.S., Vice-Pres. Gror. Soc. Dr. ARTHUR SMITH WOODWARD, F.R.S., F.L.S., Src.GE HORACE B. WOODWARD. F.R.S., MAY, 1913. - CONTENT Ay, I. ORIGINAL ARTICLES. Page REVIEWS counee Bird Remains from UpperCretaceous - Water Resources of Iowa of Transsylvania. By C. W. Did Coral-reefs exist in Paleozoic ANDREWS, D.Sc., F.R.S., British Times ?... .... i Museum, Nat. Hist. (With 2 Woods’ Cretaceous Bivalves ... Meret SCE Sead esas oan eae se LOE Brief Notices: South Biodocia = New Chalk Polyzoa. By R. M. Meteoric Iron, Missouri—Waters BRYDONE, F.G.S. Gee eV Lela aes of Poitou—TIridosmine eC O OG) (Continued.) SS oe Qa Sige er ‘Deccan; III. REPORTS AND PROCEEDINGS. a remarkable Hchinoid. By The Royal Society, March 6... ... 230 HERBERT LL. HAWKINS, M.Sce., Geological ean F.G.S. (With a Text-figure.)... Marea one eaa a eee Oo The Upper Trias of Leicestershire. Mareh 19 ... .. Se AGES) By A. R. Honwoop. (Continwed.) Edinburgh Geological Society Tao28o Fossil Plants, South Staffordshire Mineralogical Society mies ees ... 236 Coal-field. By EH. A. NEWELL- ARBER, M.A., Se.D., F.G.S. ... IV. CORRESPONDENCE. ik Eoaeee. = . Jukes-Browne ... ... ... 236 D a ~OWesliampluch=<222 20 95..-.s6 238 Dr. T. G. Halle’s Mesozoic Flora of r. H. J. Johnston-Lavis ... ... 239 Graham Land ... Geology of Ivybridge and Modbury, V. OBITUARY. Deyon ... . Hed). Mocklercs 2: secre ee Oe) Dr. Andrews’ Marine Reptiles ‘of the Oxford Clay... ... VI. MISCELLANEOUS. J. B. Scrivenor’s Géology of the Geological Survey of India ... ... 240 Federated Malay States ... ... 223 | Geological Congress, Toronto ... 240 United States Geological Survey ... 224 | Mr. Wm. 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O long ago as 1897 Baron Franz Nopesa’” recorded the discovery of numerous bones of Dinosaurs and Chelonians in freshwater deposits of Upper Cretaceous age at Szentpeterfalva in Transsylvania. Since that time he has made extensive collections of bones from the same locality and has published various papers concerning them. In his Jast collection, now in the British Museum (Natural History), there occur some fragments of limb-bones which he does not consider to be reptilian but rather of avian origin. ' These specimens he has kindly submitted to me for determination and ges DuON, and they form the subject of the present paper. The limb-bones of which portions have been pbened are the femur and tibio-tarsus. The femur is represented by two imperfect specimens: of these, one consists of the upper end and about the proximal fourth of the shaft (Fig. 1), almost uncrushed and altogether in a very good state of preservation; the other includes the upper end and the greater part of the shaft, but in this case the bone has been much crushed and broken and the head and other prominences considerably abraded. - The head of the femur (/.) is large’ and would be nearly hemispherical if it were not for the large circular fossa for the attachment of the ligamentum teres (1.t.), situated rather towards the posterior side of the head and looking inwards and backwards. Ventrally the head is marked off by a well-defined groove, but above its surface passes into that of the great trochanter (¢r.), the two being separated by a slight concavity only. The head as a whole is directed slightly upwards, rising a little above the trochanteric surface. This latter is gently convex and roughly triangular in outline, its most prominent angle projecting strongly forwards and inwards. The posterior angle is less prominent and is truncated by a deep muscle impression (0.m.), probably for the attachment of the obturator muscles. Beneath the trochanteric surface the anterior face of the bone is concave, the concavity being bounded above by the rather prominent anterior edge of the trochanter, and externally by a strongly developed forwardly directed ridge running down from the antero-external angle. The lower end of this ridge is continued 1 Published by permission of the Trustees of the British Museum. 2 Verhandl. d. k. k. geol. Reichsanstalt (Vienna, 1897), p. 273. DECADE V.—VOL. X.—NO. V. 13 194 Dr. C. W. Andrews—Upper Cretaceous Birds. on to the anterior face of the shaft as a strongly marked linea aspera, which runs downwards and obliquely across towards the inner distal condyle; its full extent cannot be seen on account of the incompleteness of the distal end of the specimen. This ridge probably marks the line of insertion of the femoro-tibial muscles. The outer face of the trochanter is concave, owing to the presence of deep pits for the insertion of muscles, probably the gluteus medius and the gluteus externus. The surface truncating the posterior angle of the trochanter and probably serving for the attachment of the obturator muscles has already been referred to. Beneath the trochanteric region the bone narrows to a shaft which is oval in section, the transverse diameter being a little the greater. The muscular ridge on the anterior face has already been referred to, and there is another strong /inea aspera (l.a.) on the hinder face, beginning just beneath the trochanter and running downwards and outwards, apparently towards the outer condyle, and becoming very strongly marked at its lower end. There is some evidence that towards its lower end the shaft curved considerably backwards. Fic. 1. Upper end of left femur of Hlopteryx nopcsai, gen. et sp. nov. A, from behind; B, from the front; C, from above. ‘Type-specimen, Znat.size. h. head of femur; l.a. linea aspera; l.t. pit for the insertion of the ligamentum teres ; 0.m. point of insertion of the obturator muscles ; tr. trochanter. In the uncrushed specimen the fractured end shows that the wall of the shaft consists of a hard compact outer layer measuring from 3°5 mm. in thickness at the front and back to about 6°5 mm. at the sides. Within this there is a spongy layer of indefinite thickness enclosing a central cavity. Judging so far as is possible from the crushed specimen, the central cavity is larger towards the lower end of the shaft, the spongy layer being less developed, while the outer hard layer also is thinner. The outer surface of the bone is sculptured in a remarkable way, being raised into a series of fine wrinkles which are for the most part irregular and run into one another, though in some places, as for instance on parts of the anterior face of the trochanter, they may be more or less parallel, and in that case, as a rule, they run more or less in the direction of the long axis of the Dr. C. W. Andrews—Upper Cretaceous Birds. 195 bone. A similar sculpture may be seen on some bird-bones, e.g. on the femur of Phalacrocorax and to a less extent in Pelecanus, but in these cases it is less distinctly seen, being partly masked by the presence of organic matter which has been removed in the fossils. Similar sculpture occurs on the fragment of a tibio-tarsus described below. This peculiarity in the texture of the surface of the bone, taken together with the similarity of form of these femora with those of some recent birds, even in details of muscle attachment and of the disposition of the linee aspere, seems to leave no doubt as to the avian nature of these remains. A fairly exhaustive comparison of these portions of femora with those of various groups of recent birds leads to the conclusion that, so far as the evidence available goes, there is reason to believe that these extinct forms approach most nearly to the Steganopodes, e.g. the cormorant (Phalacrocorax). The points of similarity are (1) the form of the great trochanter, especially the strong forward prominence of its antero-external angle, (2) the position and depth of the muscle impressions on the outer face of the trochanter, (3) the fact that the summit of the head rises above the trochanter, (4) the large ‘Fic. 2. Distal end of the right tibio-tarsus of (?) Elopterya nopesar. A, from front; B, from outer side. 2 nat. size. %.c. inner condyle; 1.g. inter- condylar groove ; 0.c. outer condyle ; 7. outer ridge. size of the pit for the ligamentum teres. Furthermore, the arrange- ment of the muscular ridges, at least in the upper part of the shaft, is closely similar to that seen in the Steganopodous femur, as is also the tendency to a backward flexure of the lower part of the bone. The bird represented by the remains just described was about as large as a pelican and is certainly different from any previously known form. I propose that it should be called Hilopteryx nopesat, gen. et sp. nov. Another specimen which seems to belong to a bird is the distal end of a right tibio-tarsus (Fig. 2), including the articular region and about two centimetres of the lower end of the shaft; both the articular end and the shaft are strongly compressed from before backwards. The articular surface consists of two sub-equal condyles, the outer (0.¢.) being a little the more prominent and convex ; these are separated by a deep intercondylar groove (7.g.), bounded above by a narrow shelf of bone which forms the floor of a deep fossa at the lower end of the anterior face of the shaft. The condyles project very little posteriorly, and pass by a continuous curve into the flat or 196 Rk. M. Brydone—Chalk, Polyzoa. very slightly concave posterior face of the shaft; the trochlear surface of the inner condyle (7.c.) extends a little higher up than that of the outer. The fossa on the anterior face of the shaft is bounded internally by a slight ridge, while on its outer side there is a strong flattened ridge (7.) running obliquely down to the upper border of the outer condyle, and perforated by a very narrow passage directed obliquely downwards and inwards. This passage is too narrow to represent the channel for the extensor tendons, present in most birds, and moreover is not in the right position. A similar foramen is present in many birds of very different groups, e.g. Didus and Dinornis ; probably it transmitted a blood-vessel. The outer face of the external condyle bears a deep rounded fossa towards its anterior border, and behind this there is a narrow deeply cut pit, both probably serving for the attachment of strong ligaments. The inner face of the inner condyle is also excavated for the attachment of ligament, but the cavity is comparatively large and shallow. Above the inner condyle on the side of the shaft there is a roughened depression for the attachment of a muscle. No very closely similar form of tibio-tarsus has been found among recent birds. The fact that the condyles are nearly equal in size and that one does not project below the other separates this tibia widely from that of Phalocrocorax, and gives the impression that the bird was not adapted for swimming, but was ambulatory. It is of course uncertain whether this tibia belongs to the same bird as the femora described above, but from the close similarity of the sculpturing of the surface of the bone in the two cases it seems most probable that this is the case. If that is so, the resemblances found to exist between the femur of Hlopteryx and that of Phalocrocorax lose some of their value, and it appears possible that the deep muscle impressions on the trochanter of the femur, though indicating a very powerful limb, do not necessarily point to an aquatic mode of life. Much more material must be obtained before it is possible to ascertain the affinities of Hlopteryx, but that a large bird existed in Transsylvania at the close of the Secondary period and in association with Mochlodon, Telmatosaurus, and other Dinosaurs is certain. It is not the occurrence of birds at this horizon that is remarkable, but the extreme rarity of their remains, while their complete absence from such deposits as the Purbeck and Wealden is still more extraordinary. The few remains that have been found in the later Secondary rocks show that the group was already highly differentiated, and in the Kocene probably all the chief orders now existing were already established. II.—Norrs oN NEW OR IMPERFECTLY KNOWN CHALK Potyzoa. By R. M. BRYDONE, F.G.S. (Continued from the March Number, p. 99.) (PLATE VIL.) fF\HERE are a number of simple Cheilostomata which develop avicularia distinctly larger than the zocecia and more or less constricted in the middle by prominent masses apparently due to R. M. Brydone—Chalk Polyzoa. 197 infolds of the side walls. schara Lesueuri, Hag. , Sp.,' 1s a good example, and others have been figured by D’Orbigny. Similar forms are not uncommon in the English Chalk, but it is curious that all the foreign forms seem to be of branching Biflustrine habit, while all the English species I have yet met with form unilaminate sheets. Mempranipora GRavENsIS, sp. nov. Pl. VII, Figs. 1, 2. Zoarium unilaminate, always adherent. Zoecia large, subpyriform, with distinct side walls and a variable amount of internal front wall, in consequence of which the areas vary from slightly elliptical to practically semicircular, but the lower lip of the area never becomes convex. Owcia helmet-shaped, large and wide, with a gently convex free edge. Avicularia about half as long again as the zocecia; above the constricting prominence they possess fairly definite side walls and front walls; these side walls thin away against the adjoining zoecia, and their bounding sutures are very hard to trace; the front walls are fairly wide and very deep-set at the head, but narrow gradually and rise steadily towards the middle; the infold of the side wall starts a long way below the level of the upper end of the area, is bold and runs with a slightly convex edge obliquely inwards until it overlies the edge of the rising front wall, and then the two edges appear to run together, meeting a little further down and inwards ; the junction is made into a small, rather brittle, projecting point by | the sharp cutting-back immediately below it of the upper part of the mass, which then passes rapidly into a rounded side wall with a steeply sloping inner surface, which flattens out until at the foot the avicularium is subpyriform like the zocecium; the area is naturally marked off by the constricting prominences into an upper and a lower section, the upper being much the larger. Avicularia are rarely developed until the zoarium has attained a considerable size, and it is therefore difficult to distinguish small zoaria from the mass of featureless specimens which it is customary to identify with some simple living Jlembranipora, but which are probably incapable of satisfactory identification. This species is at present known to me only from the zone of M. cor-anguinum at Gravesend, where it is rather scarce. Mempranrpora Sparkst, sp. nov. Pl. VII, Figs. 5-8. Zoarium unilaminate, always free and foliaceous. Zoecia normally hexagonal and equilateral, with well-marked boundary sutures, thick flat walls, and slightly elliptical areas, but very variable at times both in shape and size; at the head of the zocecium there is suddenly developed a narrow deep-set internal front wall, which is very characteristic. Owcia rare, but strong and well preserved, helmet-shaped and wide, with a free edge only slightly concave. Avicularia very sparse in occurrence, of the same general type asin MM. Gravensis, but with a strong tendency, both in external and 1 Hagenow, Die Bryozoa der Maest. Kreideb., p. 72, t. viii, fig. 17, and t. xii, fig. 12. 198 R. M. Brydone—Chalk Polyzoa. areal outline, to be long and parallel sided with pointed ends; at the head the side wall has a slight but definite thickness; the infold of the side wall has a concave edge, which never quite hides the edge of the front wall, and it can be clearly seen that these edges unite in the projecting point; the lower end of the avicularium is (in correspondence with the zocecia) simple, not subpyriform; the upper and lower sections of the area are approximately of equal size. The basal lamina is distinctive and apparently so constant in form as to be reliable for purposes of diagnosis, and I have figured a small piece. This species is. well distributed in the (restricted) zone of A. quadratus in Hants, and is abundant in Sparks’ Pit, near Cosham. MEMBRANIPORA CERVICORNIS, sp. nov. Pl. VII, Figs. 3, 4. This species, which succeeds Jf. Sparkst very closely in tine, is naturally very closely related to it, and is perhaps best described by enumerating the points in which it differs from that species. It is always adherent; the zocecia have rounded side walls and no internal front wall; the avicularia and their areas tend to be short, broad, and round-ended, the front wall is very wide, the upper section of the area is smaller than the lower, and the constricting prominences stand up very strongly and have flowing outlines suggestive of those of a deer’s antlers; no traces of ocecia have yet been observed. This species occurs sparingly in the base of the zone of B. mucronata at Portsdown. MeEmMBRANIPORA PLICATELLA, sp. nov. Pl. VII, Fig. 9. Zoartum unilaminate, free or adherent, the free specimens showing a strong tendency to tubular branching shapes, as if they had incrusted seaweeds. Zoecia elongated, roughly hexagonal, with a considerable amount of internal front wall at the foot and bounded by definite sutures ; areas of very variable size, but relatively small, roughly oblong, with gently convex sides. Oecia not yet observed. Avicularia relatively very large, of general Lesueuri-type ; there is practically no distinction between front wall and side wall at the head, the two combining into a bowl-shaped ending; the edge of the infold of the side wall seems to split into an upper and a lower lamina, the upper one being cut back very early and dying out; the area is relatively very small, being little larger than that of the larger zocecia, and narrowly elliptical, and the constricting prominences, which practically do not impinge on it, are median in position. This species is fairly abundant at Trimingham. MeEMBRANIPORA #DIFICATA, sp. nov. Pl. VII, Figs. 10, 11. Zoarium unilaminate, always adherent. Zoecia long and narrow, with flowing outlines and separated by faint sutures; areas very variable in size but relatively very small and situate quite in the upper half of the zoccia, wide and flatly Grou. MaG., 19138 Prats VII. R. M. Brydone, Photo. Chalk Polyzoa, Herbert L. Hawhkins—On Lanieria of Dunean. 199 rounded at the lower end and narrowing gently upwards, usually with obtuse angles at the upper corners due to the arising of a very slight straight- edged internal front wall at the head. Ocecia abundant, rather fragile, consisting of gentle helmet-shaped swellings with concave free edges. Avicularia with very faint boundaries, rather modified from the general Lesueurz-type; the infold of the side walls starts well above the level of the top of the area and runs downwards with a straight edge until it impinges slightly on the area close to its upper end and forms the constricting prominence, which is thus exceptionally far up the avicularium; the cutting-back below is very slight, though discernible; upwards from the point where the infold starts the side walls are straight and well marked and slope inwards to meet in an acute angle, like roof timbers, so that the outline of the front wall is that of a cross-section through a simple building; the area is a narrow ellipse, and, as indicated, the upper section of the area is very small, the lower very large. This species is well represented at Trimingham. EXPLANATION OF PLATE VII. (All figures x 12 diams.) Fies. 1,2. Membranipora Gravensis. Zone of M. cor-anguinwm, Gravesend. re 3,4. M. cervicornis. Zone of B. mucronata, Portsdown. , 5,7,8. M. Sparkst. Zone of A. quadratus, Portsdown. Fie. 6 ‘i Zone of A. quadratus, Hensting, Hants. 9. WM. plicatella. Trimingham. Figs. 10,11 wie edificata. Trimingham. II].—On ZawzrerrA, Duncan, A REMARKABLE GENUS OF THE HOLEC- TYPOIDA; WITH A PRELIMINARY NOTE ON THE TENDENCIES OF Ecurnoi Evororton. By HERBERT L. Hawkins, M.Sc.; F.G.S., Lecturer in Geology, University College, Reading. CONTENTS. Historical. Redescription of Lanieria laniert. Description of Cenholectypus cube, n.sp. The family Lanieriine, nov. The Biological Significance of the Lanieriine. Or He CO bo 1. Hisroricau. OME time after the year 1850 d’Orbigny recognized, among L) a collection of fossils from Cuba, a species that he referred to the genus Galerites under the name of G. laniert. The description and figures of the species were to have been included in vol. vill of the Historia fisica, politica y natural de la isla de Cuba, but the part of that work that should have contained them seems not to have been published. It was not until 1881 that Cotteau (‘‘ Description des Echinides fossiles de Cuba,’’ Mém. Soc. géol. Belg., vol. ix, p. 11, pl. i, figs. 7-18) gave a description of the form. He used d’Orbigny’s 200 Herbert L. Hawkins—On Lanieria of Duncan. specific name of danier?, and, with hesitation, included it in the genus Lehinoconus, as the Galerites of previous authors was then called. As Cotteau himself remarked, the name of the fossil must be ascribed to him, as d’Orbigny’s description was unpublished. In 1897 Egozcue y Cia gave a Spanish translation of Cotteau’s description (Bol. Com. Map. geol., Madrid, No. 22, p. 9), giving a reproduction of the figures, and adding further measurements and a new locality for the species. Duncan, in the Revision (1889), p. 168, very properly removed the species from Fchinoconus and diagnosed a new genus, Lanieria, for its reception. It was, and is still, the sole species of the genus. Cotteau, in the original description of the species, made use of several specimens (not all of which, unfortunately, belonged to the same genus), and gave figures of two. One of the figured specimens (Cotteau, loc. cit., pl. i, fig. 11), was in the Dewalque Collection, and is now in the British Museum of Natural History. In view of the confusion of forms described hereafter I hereby select this specimen (E. 4570) as the holotype. There are five other specimens from the same locality and collection in the Museum. AlIl of these were labelled ‘‘ Kcehinoconus lunieri”’, and among them all the main features of Cotteau’s description are included. However, only two of them (besides the type) belong to the genus Lanierta, the others being certainly referable to Coen- holectypus. It becomes necessary, therefore, to distinguish between the two types represented, and to free the diagnosis of Lanieria from the characters of Cenholectypus with which it is encumbered. At the same time some further details of the structure of Lanieria can be given. The peculiar features of the genus raise a question of phylogenetic and morphological interest. I am preparing a more detailed study of this question as it affects the Irregular Kchinoids, but the lines of argument are briefly put forward at the close of this paper. 2. Repescriprion or LAnzeRIA LANIERI (Correav), Duncan. The three specimens of this species in the British Museum are registered as E. 4570 (the lectotype), HE. 4571, and E. 4572. In the following description the first part is concerned solely with the type, additional features seen in the other specimens being added later. All the specimens are from the (?) Uppermost Cretaceous, Cienfuegos, Cuba. E. 4570. Diameter 15-9, height 14°2 mm. at ambitus. Ambulaera 3, interambulacra 7 mm. wide. Diameter of peristome 4:8, of periproct 3°9 and 2°2mm.; distance between peristome and periproct 1-8 mm. Diameter of apical system 0:8 mm. The ambitus is practically circular, and is situated about halfway between the apex and the peristome. The form of the test is almost globular, there being no appreciable flattening of the adoral surface. In fact, the specimen rests on the actual margin of the peristome, and on that alone, when placed with the adoral surface downwards. The test 1s very thin. The apical system is central, approximately circular in outline, and projects slightly above the surrounding coronal plates. The sutures J Herbert L. Hawkins—On Lawieria of Duncan. 201 between the plates are not very clear, but suffice to show that there are five large genital plates, each perforated by a large pore, and five small ocular plates minutely perforated. The madreporite is broken, but was central and apparently prominent, restricted, as usnal, to the right anterior genital. The whole apical system is typically that of a Cenholectypus. The pertproct is oval, and, although below the ambitus, is situated well up on the test, being inclined at an angle of about 45° from the horizontal. The outline is sharply pointed at both the adoral and adapical ends, the latter being slightly the more acute. . The peristome is small (compared with that of the Holectypine) and apparently quite circular. No indication of branchial slits can be seen, but the margin of the aperture is not very clearly exposed. . Diagram of adapical part of amb. iii of Lamieria lanieri [B.M. BE. 4572]. Diagram of adoral part (not quite reaching to peristome) of amb. iv of Cenholectypus cub@é [B.M. BE. 11516]. The numbers refer to plates, counted from the ocular margin. td ‘The ambulacra are straight and narrow.’ The pores of each pore- pair are slightly inclined perradially and adorally. Towards the - peristome the pore-pairs become triserial in arrangement, but they seem to recover something of their uniserial plan when quite near the peristome margin. ‘There are about four ambulacral plates to each interambulacral on the adapical surface, and apparently throughout. Only eight or nine primary ambulacrals intervene between the oculars and the ‘crushing-point’, and the full degree of crushing is 202 Herbert L. Hawkins—On Lanieria of Duncan. rapidly attained. ‘he arrangement of the plates is similar in many respects to that found in Conulus. Of the three elements of a triad the adapical one is anarrow primary with parallel margins, the median one is an extremely minute demiplate (hardly extending perradially beyond the inner pore of its pair), and the adoral one is large, about twice the height of the adapical one. The perradial suture is zigzag for the length of about twenty plates from the apex, and then becomes almost straight. The main series of tubercles is situated on the large plates, near their adradial margins, and is persistent from apex to peristome. ‘The second series is on the narrow plates, almost median, but becoming nearer to the perradial margin, and is persistent through most of the area. Both series of tubercles are of about the same size and are similar to those of the interambulacra. The interambulacra are a little more than twice the width of the ambulacra. They are composed of about twenty-seven plates per column. ‘The interradial suture is zigzag above, but becomes almost straight at and below the ambitus. The main tubercle series is not separable, in point of size, from the others. It is median on the adapical plates, but keeps at an almost uniform distance from the adradial suture throughout the column, thus appearing to pass down the outside of the area. The subsidiary tubercles that are between the two main series of an area are horizontally arranged, three or four on each plate near the ambitus. Those towards the ambulacra are in zigzag order—the principle of tuberculation being typically that of the Discoidiide. The surface between the tubercles is granulate. The test is somewhat worn adapically, but below the tubercles are seen to be in deep scrobicules. E. 4571. | Broken> | Simple> | ‘ Pygaster-like’> Hehinoidea Irregularia.| Cordiform. | Restored. | Compound.| Uniform, granular. Lameria . ; ; R A A Ra Discholectypus . : R A A Ra Conulus . : : Ra rA A rA R =retarded evolution. A = accelerated evolution. Ra = retarded, but slight progress. rA = progress, but not complete. In tracing the condition of phylogenetic development of a group it is necessary, then, to have regard to three points: (1) an analysis of the individual and a ‘diagnosis’ of each separate structure ; (2) a knowledge of the corresponding features of the original member of the group (sometimes available, often partly hypothetical); and (3) a knowledge of the ultimate possibilities of each structure in the course of its evolution (hypothetical, but to be roughly ascertained by considering the most highly developed conditions found in the group). Care must, of course, be taken to eliminate, as far as possible, conditions which are the direct results of adaptation to | environment. IV.—Tue Urprer Trias or LEICESTERSHIRE, By A. R. HORWoopD. (Continued from the March Number, p. 121.) (5) The Rhetie Outerop. LTHOUGH the Rhetic beds are not exposed continuously along the eastern boundary of the Keuper outcrop, they have been proved at many points from the River Trent in the north on the 206 A. R. Horwood—Upper Trias of Leicestershire. Nottinghamshire border to Glen Parva in the south. South of this point there is so much drift, and borings within the Liassie outcrop have been so isolated or shallow, that there is a gap in our knowledge of the intervening ground between the last point and the Rugby district. The Countesthorpe boring, carried to a depth of over 600 feet, encountered Upper Keuper beneath the Drift, with no intervening Rheetics. Commencing in the north in the Gotham district the two outliers are capped above the Red Marl and Tea-green Marl with Rheetic beds, and Lower Lias Limestone (Ps. planorbe zone) above. | At Ash Spinney at the south end of the southern outlier, and at the east end of Crownend Wood, Black Shales with Avzeula contorta crop out; and on the west side septaria are seen. On the north-west side of the northern outlier at Cottager’s Hill Protocardium phillipianum has been found in a well-section near the lane. Rheetic shales are seen in the shafts driven for gypsum works about Gotham. To the south, at Kast Leake, in the railway cutting through Normanton Hills at the south end of the tunnel, there was formerly a good section showing Lower Lias and Rhetics faulted against New Red Marl, with a very sharp line of division, a continuation of the Hoton fault, which is extended in a north-west direction to Castle Donnington, between which two points the Soar Valley obscures it; but it cuts off the Lower Keuper at Hemington, bringing the Red Marl to the surface. A section measured opposite the fault where the beds became more horizontal showed :— ft. in Stone 0 2 Shales Onset Stone 0 9 Shales Abe Stone 0 9 Shales Daw, Stone Oe Shales LAG Stone 0 6% Shales (Oy al Lower Lias } Stone On? (Planorbis | Shales 0 14 zone). Stone Og Shales 0 2% Stone 0 08 Fissile pyritic stone, parted by way-boards of shale (finch), partly conjoined with the next : P ; : : Shales q i A Stone with Ostrea liassica Shales below nodular limestone Shale , Nodular limestone Upper Rhetic shales Nodular limestone Lower Rhetic shales Tea-green Marl Orr OCOOCCOoOOCoO SENS OSS CUES BO He | tll SS?) 62 23 A. R. Horwood—Upper Trias of Leicestershire. 207 In a section Browne drew up for the Ipswich meeting of the British Association he gives the following section :— ft. Upper Rhetic shales : Droaiiaute 3 Nl, Limestone : : : Lower Rhetic shales, dark-grey ; Lower Rheetic shales, ah black (Isodonta, Myophoria) : : ‘ Sandstone, pyritous Shales, black . ; Shales, black, hard band . Thickly laminated shales Sandstone, with galena, pyritous Black shale Upper Keuper Tea-green }) Marls 5 pH oe) Onnoowr>s (=ork—=) OHMonrr ob Pa ol 8 A section on the west side, north end, showed Red Marl on one side of the fault with two skerries below a thick bedded sandstone above. ‘Tea-green Marls are shown squeezed in between this, and the Rheetic and Lias. Another section showed Lias with two beds of limestone at the Loughborough or south end of the tunnel, rising to the north above Upper Rhetics with a band of White Hur below, and Lower Rheetic beneath it. An interesting suite of fossils was obtained here (see Paleontology). Mr. W. T. Tucker found a piece of bone-bed, 2 inches thick, ‘‘ stuffed full of bones, scales, and similar to the Aust breccia.’’? About 10 feet above the Tea-green Marls a fish-band was found, also coprolites, vertebre, and teeth. He also noticed a nodular band 80 feet below the first Lias grey nodular band, with 20 feet black shales beneath it. If so, the Rheetics here were 50 feet thick. At the junction between the Tea-green Marls and the black shales there was a yellow band, but no regular bone-bed. The Tea-green Marls showed traces of erosion. At the north end of the tunnel the dip was 6° to the south. At the south end it was 2°-6°. To the east at Costock at Flint Farm in the stream section flinty limestone is exposed, and some pits about here were formerly worked for limestone. To the south at Rempstone flinty limestone occurs at Sutcliffe Hill, and where the outcrop crosses King’s Brook. The Stanford fault shifts the outcrop again to the west, and about Stanford Hall in the trough high sround is probably formed by these beds. Between Walton nal Bano, in the valleys cut through the Drift and Lower Lias, the Rhetics have been exposed on each side of the brook, and the outcrop is continuous between here and Walton, black shales being struck in a well 500 yards west-south-west of Walton Church. The outcrop continues westward from here to Barrow Hill. H. B. Woodward! recorded the occurrence of Rheetics at Barrow- on-Soar, and remarked that ‘‘ above the black shales there was a considerable thickness of apparently unfossiliferous grey earthy ' Ansted (1866) noted them earlier. 208 A. Rk. Horwood—Upper Trias of Leicestershire. marl, capped by a hard bed which I took to represent the upper limit of the Rheetic formation. Above it the ordinary Lower Lias limestones and clays come on”’. Laminated lumpy shales overlying Tea-green Marls have been exposed in the Midland Railway cutting 600 yards north-west of the station. South of Barrow at Netherfield grey shale and nodular limestone was found with a dip of 12°, accentuated by the Barrow and Sileby fault. At Barrow Hill black shales and a bone-bed overlaid Tea-green Marl. To the south, in the Wreake Valley, Lias comes on directly against Red Marl owing to the Sileby and Barrow fault, which causes a displacement of the beds to the west, and in a well-sinking at Ratcliffe Boulder-clay (80 feet) rests on Red Marl, showing they are absent here. The lowest beds of the Lower Lias are seen to the east at Kirby Bellairs, so that the fault runs north of the Wreake Valley. In the boring for water at Melton Rhetic black shales and a nodular limestone 16 ft. 4in. thick rest on 247ft. 10in. of Red Marl, with sandstone near the base, and gypsum beds. At Brooksby Red and Grey Marls are found up the Wreake Valley, indicating the extension of the Rheetics so far east. In the stream-side between Queniborough and Gaddesby Grey Marls and mottled clays are exposed, and further south near the village east of the new hall Grey Marls are seen along the slopes. In the brook at Barkby and half a mile from the village Grey Marls are also exposed, as well as in fields. At the New York Farm on the Ridgemere road, black shales were met with for 52 yards. Paper shales have been exposed on the ridge north of the fault at Barkby- thorpe, which makes a bold escarpment. At Humberstone the Rhetic beds have been exposed at various points and pierced by borings and well-sections to the east of the Spinney Hills in the low ground between the latter and Crown Hills from Evington Road to Uppingham Road. The shales were struck in the boring at Lodge Farm (2) and appear in the other adjacent or Crown Hill borings (16 ft. 9in.), but were absent in the Willow Brook boring. They crop out in the Humberstone drive, where Lower Lias beds succeed them. The well-boring at the Asylum pierced Lias and 20 ft. of Rhetics with nodular limestone. The nodular septaria were recently met with in a well in Freeman’s Road North below river gravels, and the slopes at the junction of Green Lane and Coleman Road are in Rheetic shales. At the top of the Gipsy Lane Pit, on the east side, thin bands of black shales succeed a thick section of Tea-green Marl. At their junction I found Zstheria minuta. In a small pond in a field to the east they are again exposed. Following the hillside they run in a north-east direction to a point just north of the Humber Stone, where in a ditch the line of fault brings the Red Marls against the black shales in the second field on the Humberstone and Barkby- thorpe bridle-road. In an excavation for St. Philip’s Church 2 feet of Rhetic shales were encountered beneath 9 feet of soil and drift. In Green A. R. Horwood—U; ‘oper Trias of Lewestershire. 209 Lane Road 2 feet of shales were found in a well-section under 8 feet of soil and drift, and they outcrop in the ditch on the west side. There has been some discrepancy as to who first discovered the Rheetic beds at Leicester. Mr. J. J. H. Teall, F.R.S., reported their oceurrence here in 1874, but they were not then actually recorded. Later on Mr. W. J. Harrison described them in 1876 in the Report of the Geological Section to the Leicester Literary and Philosophical Society. The section of Rheetics at the Spinney Hills, now built over, was described by W. J. Harrison in 1876. Then three brick-pits were situated on this ridge, which forms the Rheetic escarpment between Humberstone Road and Victoria Park. ‘The valley between has been excavated, and only the Tea-green Marls are visible, but eastward the Rhetics come on again. The floor of the pits was in Red and Blue Keuper Marl (10 feet) with selenite and salt pseudomorphs. He notes the diminished thickness of the red bands at the top of the Keuper. There are about 16 feet of Tea-green Marls below the Rheties here, which are black shales about 10 feet thick. The higher beds with a second nodular limestone were noticed in other excavations. . The section here (Moore’s Pit, junction of Wood Hill and Prospect Hill) was :— Soil and drift, with flintimplementsand Roman ft. in. pottery, etc. ¢ : : A : é 1 0 Nodular band of limestone, with casts of Estheria, Avicula contorta . : : : light-coloured shales, with sandy partings, Modiola minima, Avicula contorta, Cardium rheticum . é ; ; : 4 P 4 Dark shales, with sandy partings, Ophiolepis ae damesit, Pho lidophorus mottiana ( = higginst) 1 Ruste, Finely laminated black shales, Avicula con- torta, Cardium rheticum . : Sandstone = Aximus bed, worm-tracks Black shales, coarsely laminated : : Bone-bed, Gyrolepis, Saurichthys apicalis, Hybodus minor, Ceratodus, Nemacanthus monilifer, Ichthyosaurus, Plesiosaurus, \. Sargodon tomicus, etc. ; é : : Upper | lush sandy shales with hard courses, 0 6 bo © bo (or =) i=) S bluish nodules on lower part, fish scales . 16 0 AST Red and Blue Upper Keuper Marl . : 6 Oy © a7 4 The upper surface of the Red Marl was uneven, hollowed out in long curves. The dip was south-east. The Tea-green Marl was green in parts, with blue nodules in the lower part, fissured, and with conchoidal fracture. Selenite occurs in it, and pseudomorphs of salt crystals, as well as ripple-marks. Fish-scales are numerous. I have examined these, and they are of the Semionotoid type. In the same material Zstheria minuta is abundant. Teeth also occur. Mr. Harrison said he found a single insect wing here, but I think this must have been Zstheria, as he said it perished on exposure, a feature common to Zstheria. The upper surface was uneven. DECADE VY. VOL, X.—NO. V. 14 210 A. R. Horwood—Upper Trias of Leicestershire. Rain pittings were abundant. In the unweathered state the bone- bed is hard, but the contents brittle. Harrison obtained from here large vertebrae of Jchthyosaurus, rib bones belonging to Plesiosaurus (one 18 inches), and Labyrinthodont bones, worn and rolled bones, coprolites containing small quartz pebbles and bits of Dane Hill Sandstone. Pebbles are mainly quartzose or of slate, and rounded ; some 3—4 inches, of local origin. sodonta occurs loose in the bone-bed. The Pullastra Sandstone is reddish, and 3-1 inch thick. The first British example of Ophiolepis damesii was found here, but others have recently been found elsewhere. It is probably dimorphic, with alarge andsmallform. Recently fine large types have been found at Glen Parva, as well as the smaller type. Both were regarded by Wright as belonging to this species. Kaolinite, bitumen, selenite, and mica are common in the dark shales with sandy partings. In the nodular limestone the stheria occurred with __— THE AGE OF THE TORBAY RAISED BEACHES. Srr,—If Mr. A. R. Hunt desires to be an effective critic and not a mere needless fault-finder, he should not base an argument on ancient history and ignore modern research. He thinks it ‘ unfortunate” that in dealing with the evidence of raised beaches in a recent paper on ‘* The Making of Torbay” I made no reference to the ‘‘ voluminous literature”? concerning them, and he writes as if he supposed there had been no change of opinion about them since the discussion which took place at the Geological Society in 1890. Apparently he has not realized that the whole question of the age of the raised beaches in Devon and Cornwall has entered an entirely new phase since the discovery that the raised beach of Gower (in Correspondence—A. J. Jukes-Browne. _ 237 South Wales) is older than the local glacial deposits. That discovery was made by R. H. Tiddeman in 1900, and was published in this Magazine for that year. Moreover, in 1903 Messrs. Wright and Muff (Maufe) proved that the 12 to 15 ft. raised beach in the South of Ireland was also relatively pre-Glacial. These observers have shown that the descending succession in both countries is as follows :— Upper head or local rubble. Glacial deposits. Lower head and cave earth. Raised beach. In Devon and Cornwall the succession is the same where most complete, but is usually without any glacial deposit, because the area was probably outside the lmits of continuous ice even at the epoch of maximum glaciation. An accumulation has, however, been found above a raised beach in the Scilly Isles, which Mr. Barrow has not hesitated to describe as ‘‘ a glacial deposit’, and his final remarks regarding it are so much to the point that I may be excused for quoting them. He says: ‘‘he occurrence of this [deposit] is of the utmost importance, for not only can the old beach be now seen to be identical with that on the Cornish coast, but it is obviously contemporaneous with that described by Messrs. Wright & Muff(Maufe) occurring on the south coast of Ireland. It is also identical with that occurring in the South Wales area, for in both instances the head overlying the old beach is capped by a Glacial deposit. Thus, then, the old beaches in the Scilly Isles, in Cornwall, in South Wales, and in the South of Ireland are not only contemporaneous, but in addition are older than part of the Glacial Deposits” (The Geology of the Isles of Scilly, Mem. Geol. Survey, 1907). To this I need only add that Mr. Ussher has accepted the same date for the raised beaches near Plymouth (Mem. Geol. Survey, 1907). Naturally, therefore, in dealing with ‘‘ The Making of Torbay”’ I thought it was sufficient to state that the age of the raised beaches in Devonshire had been so determined, and consequently I did not refer to the ancient history of the question. Mr. Hunt, however, is bold enough to assert that ‘‘ the intrinsic evidence of the Torbay beaches against an early glacial antiquity is very strong”, and he indicates three lines of evidence, viz. those of flint implements, Molluscan fauna, and geographical position. He says that flints of recognized Neolithic age have occurred ‘‘ at Hope’s Nose in Torbay, in the Irish beaches, and in the Scotch beaches, all within the 25 foot level or terrace’’.. Now, if by the words “ at Hope’s Nose’’ he means in the material of the beach we should like to have particulars of the find. The neolith obtained from the floor of Torbay proves nothing, neither do the finds in the raised beach of Antrim or in the Scotch 25{ft. beach, because it has been shown that the land-movements in the north were quite different from those in the south-west of the British area. Mr. Hunt’s second argument, based on the non-Arctic character of the Molluscan fauna, is specious but fallacious, because we have no standard of comparison within the areas of the English and Bristol 1 GEOL. MAG., 1900, pp. 441-3. 238 Correspondence—G. W. Lamplugh. Channels, and we do not know how much the Molluscan assemblage in the Channel waters was affected by the cold of the Glacial Period. If I am right in believing that the Straits of Dover did not exist at the time when the raised beaches were formed, and that the Channel Sea was then a gulf opening westward, it is probable that the temperature of the water was never very much lowered, and that its fauna underwent very little change from early Pleistocene time to the present day. With regard to Mr. Hunt’s geographical facts, I quite fail to see their bearing or why a beach at Hope’s Nose should ‘ represent a very much later stage of coast erosion” than one at Portland Bill. The matter stands thus: It is not a case of all the available evidence tending to show that I did not know what I was writing about; the geological facts are as I have stated above, and if Mr. Hunt declines to accept the inferences that other people have drawn from them, he will have to adduce much more definite and cogent reasons for his disbelief. It will certainly take all he can get out of ‘‘ geography, conchology, physics, paleontology, archeology, anthropology, and micro-petrology ” to upset the geological evidence ! In 1905 he had to admit that he had completely misunderstood one important particular in Messrs. Wright & Muff’s (Maufe’s) account of the Cork raised beach, and it now looks as if he had quite failed to realize its bearings in another direction. 5 A. J. Juxrs-Browne. P.S.—Since writing the above I have discovered what Mr. Hunt meant by his reference to a Neolithic flint ‘‘ at Hope's Nose”’. It is recorded in one of his own papers,! and, as I suspected, it was not found in the beach itself. His words are: ‘‘I noticed a flint flake jutting out of a stratum of landwash at the top of the little cliff just east of the Hope’s Nose beach. It was about two feet below the surface. With it there were three other fragments and two littorina shells. I sent the flake with one of the smaller pieces to Sir John Evans, K.C.B., who replied: ‘ Both the enclosed seem to be artificially made flakes probably of Neolithic date.’ As there are some flints in the raised beach, it seems possible that these flakes were made on the spot.” It is evident, therefore, that Mr. Hunt knew that the flint was only a flake, and that it did not occur in the material of the beach but in landwash above it; yet he blandly quotes its occurrence as an argument against the early Pleistocene age of the beach! It will be interesting to learn what explanation Mr. Hunt has to offer. Ac. Je SB. WESTLEIGH, ASH HILL ROAD, TORQUAY. AGE OF RAISED BEACHES. Str,—In an ingenious classification of the Raised Beaches and associated deposits of the South and West of England, Mr. H. Dewey (Grot. Mac., April, 1918, pp. 154-68) refers to similar beaches in the: South of Ireland and brings them within his scheme. By a round- about argument from their hypothetical relationship to the Thames. ' Trans. Devon Assoc., vol. xxxvi, p. 475, 1905. Correspondence—H. J. Johnston-Lavis. 239 gravels, all these beaches are ranked in the scheme as newer than the Chalky Boulder-clay. But the only Infra-glacial beach that is known to occur within the region of the Chalky Boulder-clay, viz. that which is at times clearly exposed at Sewerby on the Yorkshire coast, is left entirely out of the reckoning. Thorough investigation of this beach by digging and borings in 1887-90 enabled me to show that it was older than the oldest (‘ Basement’) Boulder-clay of the York- ‘shire coast, which is at least as old as the Chalky Boulder-clay. Further, there can be no doubt that the Infra-glacial beaches of the South of Ireland, with which I am well acquainted, are of practically the same age as the Sewerby beach and stand in the same relationship to the glaciation. There seems every reason, also, for supposing that the Infra-glacial beaches of South Wales belong to the same period. If Mr. Dewey be right in his correlation of the beaches of Devon and Cornwall with those of the South of Ireland, it would follow that they are older than the Chalky Boulder-clay, and not newer. But, in the absence of Boulder-clays south of the Bristol Channel, the correlation has still an element of uncertainty. Deposits of the character of ‘Head’ and ‘Combe Rock’ are unsatisfactory materials on which to base conclusions as to time-divisions of the Glacial period, since it is clear that rubbles of this type were being formed locally throughout the period in areas not covered by ice. In Yorkshire, though the chief masses occur beneath all the Boulder- clays, the rubbles are by no means confined to this horizon. G. W. Lamriuen. St. ALBANS. April 18, 1913. SHA-WATER AND CRITICAL THMPERATURES. Sir,—I certainly have never written a paper with the actual title referring to critical temperatures, but very much of my life has been spent in promulgating the view of the solubility of H?O in fused silicates and laying down the fundamental principles of varying volcanic action based upon that as illustrated in fragmentary ejecta. Neither the critical temperature of water nor the spheroidal state has anything to do with the question, which, I have always maintained and repeat, depends on the critical temperature and pressure of solution of gaseous oxides (H?0O), etc., in fused liquid oxides and silicates. Curiously enough, my views have never been much referred to in England, but are very generally accepted by Continental geologists, which, if we are to believe Mr. A. R. Hunt, means that English geologists read very little either the researches of their own country- men or those of foreigners. Nine of my papers in the list mentioned by Mr. Hunt refer to the subject under discussion, and I am now sending him a new list up to date of 161 papers, in which four others treat of the same question. H. J. Jounston-Lavis. BEAULIEU-SUR-MER, FRANCE. April 7, 1913. 240 Obituary—Frederick James Mockler. Ob rt TOA ye FREDERICK JAMES MOCKLER, Freperick JAMES Mécxkter died on March 12, 1918, aged 68. After a varied career, in which he became best known, perhaps, as an authority on Baxter Prints, Mr. Méckler was appointed curator of. the Holburne Museum, Bath, a post which he was obliged to vacate some ten years ago on account of ill-health. Up to this time he had | become acquainted with geological matters by handling material of Charles Moore’s collecting, and by gathering and washing Faringdon Sponge Gravel for the use of E. C. Davey in his work on the fossils contained in that deposit. It was not, however, until his employment for preparation-work in the Geological Department of the British Museum that he found scope for the exercise of the skill, amounting to genius, with which he resolved intractable sediments into a paste from which the particles of clay could be washed, and extracted thence organisms of extreme minuteness and delicacy ; taking a genuine pleasure in the labour involved in picking over the residues grain by grain and separating the fossils from the inorganic particles. Itis too soon to be possible to estimate the value to science of his labours; this will be fully appreciated by those who in future work out the Museum collections of Foraminifera, Polyzoa, Echinoderms, ete., with the material his skill has provided. But the untiring industry and humble conscientiousness with which he employed his talent declared his value to those who knew him. Science has lost in him a hard- working devotee, and his colleagues a genial and warm-hearted friend. W.; dose MIiSCHILUAWN HOUS.- SPR EST GrorocicaL Survey or Inpra.—The Secretary of State for India in Council notifies that one appointment to the Indian Geological Survey Department will be made in July next. A further vacancy is expected to occur in the year 1914. INTERNATIONAL GEOLOGICAL Concress.—Since the preliminary notice of the Session to be held in Toronto (given in the GxrornogicaL Maeaztne for September, 1912, p. 431), the dates of the meetings have been fixed to commence on Thursday, August 7, and to terminate on Thursday, August 14, 1918. Particulars have now been printed concerning the dates of excursions, the areas to be visited and the cost, accompanied by maps of the routes. (See second circular, to be obtained from the Secretary, Twelfth International Geological Congress, Victoria Memorial Museum, Ottawa, Canada.) GrotocicaL Socrery or Lonpon, Aprit 9, 19138.—Mr. Wilham Rupert Jones (son of the late Professor T. Rupert Jones, F.R.S.), who has filled the office of Assistant Librarian to the Geological Society, will retire on pension after forty years’ service. He was a man with a remarkable knowledge and memory, and for many years had prepared a valuable list of additions to the Society’s Library, which was regularly printed and circulated to the Fellows. : BRITISH MUSEUM (NATURAL HISTORY) NEW PUBLICATIONS. Catalogue of the Collection of Birds’ Eggs in the British “Museum (Natural History). Vol. V. Carinatez (Passeri- formes completed). By W. R. OgiLviE-GRANT. 8vo. pp. xxiii, 547, with 22 coloured plates. Cloth. £2 7s. 6d. Catalogue of the Chzetopoda in the British Museum (Natural History). A. Polycheta.—Part I: Arenicolide. By J. H. AsHwortH. Roy. 8vo. With 15 plates. Cloth. 27s. 6d. MILLER (G.S.). Catalogue of the Mammals of Western Europe (Europe exclusive of Russia) in the Collection of the British Museum. §8vo. pp. 1034, with illustrations. Cloth. 26s. History of the Collections contained in the Natural ‘History Departments. Vol. II: Appendix, Zoology, 1856 to 1895. By Dr. A. GuNTHER. 8vo. pp. 118. Cloth. 5s. A Descriptive Catalogue of the Marine Reptiles of the Oxford Clay, based on the Leeds Collection in the British Museum (Natural History). Part II. pp. 280; 78 text- figures and 14 plates. 4to. Cloth. £1 5s. Part I, 1910. 4to. pp. 228; 94 text-figures and 11 plates. Cloth. £1 5s. 8vo. Cloth, £1 is. Observations on the West of England Mining Region. - Being an account of the Mineral Deposits and Economic Geology of the Region, and forming Vol. XIV of the Transactions of the Royal Geological Society of Cornwall. By ob) COLEINS. FG. JUST PUBLISHED. THE OLDER PALZOZOIC SUCCESSION OF THE DUDDON ESTUARY. 8vo. pp. 24. With map and 2 figs. in text. Sewed. Is. net. DULAU & CO., LTD., 37 SOHO SQUARE, LONDON, W. CLIMATIC CHANGES SINCE THE LAST ICE AGE. A Collection of Papers read before the Committee of the Eleventh International Geological Congress at Stockholm, 1910. 4to. Sewed. £11 net. THE IRON ORE RESOURCES OF THE WORLD. A Summary compiled upon the initiative of the Executive Committee of the Eleventh International Geological Congress, Stockholm, 1910, with the assistance of Geological Surveys and Mining Geologists of different Countries. EDITED BY THE GENERAL SECRETARY OF THE CONGRESS. 2 vols. 4to. Wirth 28 plates and 137 tlustrations in the text, and accompanied by a folio Atlas of 42 maps. Price £3 net. DULAU & CO. LTD., 37 SOHO SQUARE, LONDON, W. THE SUBANTARCTIC ISLANDS OF NEW ZEALAND. Reports on the Geophysics, Geology, Zoology, and Botany of the Islands lying to the South of New Zealand. Based mainly on observations and collections made during an expedition in the Government steamer Hzvemoa (Captain J. Bollons)in November, 1907. Edited by CHAS. CHILTON, M.A., D.Sc., F.L.S., Professor of Biology, Canterbury College, University of New Zealand. Profusely illustrated with full- page plates, photographs, and text-figures, and a large map of the Antarctic and Subantarctic Regions specially compiled and based on the most recent surveys. In two volumes, demy 4to, of about 4oo pages each, 42s. net. JUST PUBLISHED. CATALOGUE OF GEOLOGICAL WORKS No. 15—Dynamical, Palaeontological, and Stratigraphical. Post free on application. All Communications for this Magazine should be addressed to THE EDITOR, 13 Arundel Gardens, Notting Hill, London, W. Books and Specimens to be addressed to the Kditor as usual, care of MESSRS. DULAU & CO., LTD., 37 SOHO SQUARE, W. STEPHEN AUSTIN AND SONS, LTD., PRINTERS, HERTFORD. Decade V.—Vol. X.—No. VI. GEOLOGICAL MAGAZINE Monthly Journal of Geology. WITH WHICH IS INCORPORATED See Son Oia, @ Goes see HENRY WOODWARD, Proryssor J. W. Dr. GEORGE EDITED BY ASSISTED BY GREGOR J. HINDE, ies Ds Y, D.8c., F.R.S., ReneS hEEGES + Cec: F.G.S, WIR ISog Weiss, Sir THOMAS H. HOLLAND, K.C.I.E., A.R.C.S$., D.Sc., F.R.S., F.G.S. PrRoressor W. W. WATTS, HORACE B. Sc.D., M.Sc., F.B.S Dr. ARTHUR SMITH WOODWARD, F.R.S WOODWARD, F.R.S., ., VICE-PRes. GEOL. Soc. ., F.L.S., Ske. Gro. Soc. Hs Giese JUNE, 1913. PC @Qy eh Baw rs ~ I. ORIGINAL ARTICLES. Eminent Living Geologists: James Geikie, LL.D., D.C.L., F.R.S., Professor of Geology, University of Edinburgh. Plate IX.) New Chalk Polyzoa. BRYDONE, F.G.S. (Continued.) . The Rigidity of the Barth. By the Rev. O. FISHER, M.A., F.G.S. “By R. M. (Plate VIII.) wae a Portrait,’ Page Minerals of the Barrington Bone- bed. By R. H. RASTALL, oe F.G.S. ee ee Limbs of Lystrosaw: US. . 8. WATSON, M.Sc. s Tee figures.) : Occurrence of the layne in ‘North Wales and Derbyshire. By J. WILFRID JACKSON, F.G.S. (With 2 Text-fieures.) ... .. Submerged River-valleys. ByR.M. DEELEY, F.G.S., M.Inst.C.E. . (outh African Cretaceous Dinosaurs II. REVIEWS. 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MISCELLANEOUS. International Congress... .. South African School of Withee . 284 . 286 --. 288 . 288 ... 288 .. 288 Ba eS The Volume for 1912 of the GEOLOGICAL MAGAZINE is ready, ¥3 e 26s. net, Cloth Cases for Binding may be had, price Is. 6d. net. Price 2s. net. TWO IMPORTANT BOOKS. The Building of the Alps. T. G. BONNEY, Sc.D., LL.D., F.R.S.; Emeritus Professor of Geology, University College, London ; Past President of the Alpine Club, the Geological Society, and the British Association. With 48 Illustrations. Demy 8vo, cloth. (Second Impression.) 12s. 6d. net. ‘The result of all this learning and experience is a book of absorbing interest to anyone who passes a summer or a winter season in the Alpine region and wishes to make’use of his eyes or his imagination. . . . Whatever Dr. Bonney’s attainments as a geologist, he adds to them the power of writing a language which can be understood by those who are not geologists.’’—Times. ‘* Tt is not simply a technical treatise, but a vivid, picturesque, and fascinating account of the life history of the Alps.’’—The Freld. Hampstead Heath: Its Geology and Natural History. BY MEMBERS of the HAMPSTEAD SCIENTIFIC SOCIETY. With a Coloured Frontispiece, Maps, and other Illustrations. Demy 8vo, cloth. 10s. 6d. net. The Natural History Section of the Hampstead Scientific Society has for many years been exploring the district. This work contains chapters on bird life, plant life, and pond life; on mammals, molluscs, and insects. Mr. F. W. Rudler discusses the geology of the area, which for London is of peculiar interest; the general features of the Heath are described in a topographical section, together with so much of its history as affects or explains its present aspect; and there is an account of local meteorology, based partly on the records of the Society’s own observatory and partly on such previous records as are available. Although the book is written in a clear and popular style, it is at the same time a careful and accurate scientific survey of the district. T. FISHER UNWIN, 1 Adelphi Terrace, London. Grou. Mac. 1913. Puatrt 1X ” eR, aug Same fo PROFESSOR JAMES GEIKIE, LL.D., D.C.L., F.R.S., Etc. By permission, from a photograph by Messrs. Elliott & Fry, Ltd. THE GEOLOGICAL MAGAZINE NEW SERIES. DECADE V. VOL. X No. VI.—JUNE, 19138. ORIGINAL ARTICLES. T.—Emrvent Livine GxoLocists. James Gerxie, LL.D., D.C.L. (Dunelm.), F.R.S. L. & E., F.G.S. Murehison Professor of Geology and Mineralogy and Dean of the Faculty of Science in the University of Edinburgh. (WITH A PORTRAIT, PLATE IX.) \HE name of Geikie has become as familar to present-day geologists as those of Murchison, of Sedgwick, or of Lyell were to our immediate predecessors. Notices and portraits of his elder brother, Sir Archibald Geikie, K.C.B., the President of the Royal Society, have already appeared in the GrorocicaL Maeazrne (see Vol. for 1890, Pl. II, pp. 49-51, and 1907, Pl. I, pp. 1-2); it is high time to present that of the younger brother, Professor James Geikie, who occupies the leading place in our science and in geography in “idinburgh and its University, and is known everywhere also by his published works, especially by his contributions to Glacial Geology. James Geikie was born in Edinburgh August 28, 1839, and after being educated at the High School and the University of his native city, he entered the Geological Survey in 1861, and became a District Surveyor in 1869. ‘‘In those early days,’’ writes James Geikie, ‘‘ when I joined the Geological Survey in Scotland, the Survey maps showed only the ‘solid geology’; the loose superficial deposits known generally as ‘drift’ were entirely ignored. It was then decided that the ‘drift? should henceforth be mapped, and thus my earliest years on the Survey were spent in re-surveying ground which had already been mapped so far as the solid geology was concerned, my work being confined to the insertion on the field-maps of the so-called ‘drift’ and peat. From the first, therefore, I became interested in our ‘superficial formations’, more especially in the Boulder-clay and the gravels and sands associated with it. My interest in these deposits, however, dates much further back—in fact, to my school days; so that I did not come to the Survey quite a greenhorn so far as the drifts were concerned. “ Later on, while mapping in the Southern Uplands, the peat-bogs, with their remains of trees, arrested my attention, and seemed to suggest that the explanation of the phenomena then in vogue was » insufficient. Accordingly my holidays for a few years were spent in _ the Highlands and Outer Hebrides, for the purpose of increasing my DECADE V.—VOL. X.—NO. VI. 16 242 Eminent Living Geologists— knowledge, not only of peat, but of ‘superficial formations’ generally. Eventually I reached the conclusion that the phenomena of the peat bore witness to a succession of climatic changes, and my views were communicated to the Royal Society of Edinburgh in a paper ‘On the Buried Forests and Peat-mosses of Scotland, and the changes of climate which they indicate’! (1866). ‘‘T have, since then, considerably extended my acquaintance with the peat-bogs of Scotland and other lands, but have found no reason to change or modify the general conclusions I arrived at so long ago —conclusions which have been of late years strongly supported by Dr. Lewis, whose researches into the botanical history of the peat- mosses seem to me to mark a distinct advance in our knowledge of Pleistocene geology.” Dr. James Geikie’s survey work in succeeding years lay chiefly in the Lowlands, and the bordering tracts of the Southern Uplands and Highlands. He had thus to map considerable areas of Silurian, Old Red Sandstone, and Carboniferous, together with large tracts of the associated igneous rocks. This ‘solid geology’ was sufficiently engrossing, but the glacial phenomena had certainly the greater fascination for him, and most of his holidays were devoted to the study of these phenomena either in this country or on the Continent. Having arrived at certain conclusions as to the climatic changes of Pleistocene times, he broached these views in the Gxrotocican Magazine (1871-2) in a series of papers ‘‘On Changes of Climate during the Glacial Epoch”. These papers formed the germ of James Geikie’s Great Ice Aye, issued in 1874, a second edition of which appeared three years later. His Prehistoric Europe, published in 1882, was really a supplement to that edition, while the third edition of the Great Ice Age (1894) embodied the further results obtained by assiduous study of the work done by others, and by the devotion of his holidays to research in this country and abroad. Having been appointed (1882) to the Chair of Geology at Edinburgh, many new interests claimed his attention. His pupils having com- plained that the textbooks of geology then available were either too meagre or too elaborate for their purpose, Professor Geikie was induced to prepare an ‘intermediate’ textbook ( Outlines of Geology) which was issued in 1884, a fourth edition being called for in 1903. He also set himself the task of improving the teaching of geography in schools. The kind of geography taught at that time and the textbooks in common use were dry and forbidding, and one had no difficulty in proving that such was the case. But James Geikie was only one of a number of ardent reformers, who in 1884 united to form a Scottish Geographical Society, which has succeeded beyond their utmost expectations, and has played no small part in effecting a complete revision of the mediaeval system of teaching geography in the Scottish schools, and in getting lectureships on the subject established in the universities. Dr. James Geikie was elected president in 1904, but after holding office for six years his constantly increasing work at the University compelled him to resign. On his retirement 1 See GEOL. MAG., 1867, pp. 20-3, and Roy. Soc. Edinb., vol. xxiv, pt. ii, pp. 363-84. ! Professor James Geikre. 243 the Council awarded him the gold medal of the Society, and invited him to have his portrait painted for the Society’s hall. Professor James Geikie has for many years acted as Honorary Editor of the Society’s organ, the Scottish Geographical Magazine, one of the best scientific journals extant. His long connexion with the Royal Scottish Geographical Society induced him frequently to bring before his associates the importance of geology to all serious students of geographical science, and. he summed up much of what he had advanced, in lectures and papers on the subject, in arth Sculpture or the Origin of Land Forms (1898; last edition, 1909). Dr. Geikie has now in the press another similar work dealing with the borderland of geology and geography, but treating more especially of mountains. Meanwhile his interest in the history of the Ice Age has not abated. A few months ago he delivered a course of lectures in the University (under the ‘Munro Foundation’) on the ‘‘ Antiquity of Man in EKurope’’, in which the subject was discussed mainly from the geological point of view. . As a teacher Professor Geikie has of course endeavoured to give as wide a view of the stony science as one man can be expected to do. In the early ‘eighties’ he had to do all the work of his department single-handed, lecturing, demonstrating minerals, rocks, and fossils in the laboratory, as well as conducting field excursions. By and by, however, the department was strengthened by the appointment of able lecturers and assistants, and is now probably as well equipped as any similar school in the kingdom. Students of applied science are, as might be expected, more keenly interested in practical work than in paleontological research or historical geology. From the first, therefore, Dr. Geikie endeavoured to meet their special requirements by devoting the summer term to the study of structural and field geology, and in 1898 he issued a textbook on the subject, which has gone through three editions (the last appearing in 1912), so that the book has apparently met a ‘felt want’. Some years ago he began to form a lending and consulting ‘class library’ for the use of his students, which has now grown to respectable dimensions, thanks largely to generous contributions of geological literature from his brother, Sir Archibald Geikie. It contains upwards of 5,000 volumes, and many thousands of ‘separates’ from the scientific journals of this and other countries, besides a large collection of geological maps. This library (with the _ consent of his brother) has been presented to the University. While busy enough with his duties as a teacher, Professor Geikie yet found time to take part in the administration of the University, having acted since 1891 as Convener of the Science Degrees Committee, and subsequently, after a Faculty of Science had been instituted by the Royal Commission in 1894, his colleagues did him the honour to elect him their Dean, an official position which he still holds. Since James Geikie joined the University in 1882 great changes have taken place. Not only have several new Chairs in the Faculty of Science been founded, but numerous additional lectureships have been instituted, and the whole system of teaching has been in a measure revolutionized. More especially is this noticeable in practical work— 244, Eminent Living Geologists— the provision for which is constantly being increased by the enlarge- ment of old laboratories and the building of new ones. Asa relief from professional work Professor Geikie has indulged, as most folk do, in hobbies. One of these has been the study of foreign literature—not wholly geological, as the issue of a volume of translations of Heine’s Songs and Lyrics may serve to show. But not much idle time outside his professional duties has been allowed him, for he has been twice elected a President of a section of the British Association, that of Geography in Edinburgh and of Geology at Newcastle ; while the United States carried him off to America to deliver « course of lectures at the Lowell Institute in Boston. Professor James Geikie received the Brisbane Medal of the Royal Society of Edinburgh and also the Murchison Medal of the Geological Society of London in 1889. In presenting the latter Dr. W. T. Blanford, then President of the Geological Society, said: ‘The Council has awarded the Murchison Medal to Professor James Geikie in acknowledgment of his important contributions to the geology of, North Britain, and especially of his investigation of glacial phenomena. His Great Ice Age contamed a. full, careful, and admirably written summary of the observations made up to 1874, and the interest excited by the work was proved by a second edition being required in 1877. Professor Geikie has besides published numerous papers, not the least important of which were two that appeared in the Society’s Quarterly Journal containing his observa- tions ‘On the Glacial Phenomena of the Long Island or Outer Hebrides’.”’ A third edition of his Great Ice Age (largely rewritten) was published in 1894, and although so long a period had elapsed since the second edition appeared it speaks highly for the author’s merits and charm as a writer that the book had lost none of its interest with geologists, nor with the reading public in general. One of the most important advances made in glacial geology is afforded by the various evidences which have been brought to ight which tend to establish the conclusion that prehistoric man was living and resident in Europe probably before the Great Ice Age, and certainly during the several mild interglacial periods which occurred prior to the final removal of the intense cold and the great permanent snow-fields of the Northern Hemisphere. In a valuable and exhaustive notice of Dr. James Geikie’s work at the time (see Grot. Mag., 1895, pp. 29-38) Dr. Hinde observes: ‘‘ Opinions may differ respecting some of the generalizations of the author, but all will agree on the value and importance of having the evidence on this subject stated in so clear and impartial a manner.” The warmest personal regard is entertained for Professor James Geikie, not only by his many friends and fellow-workers, but by the still larger number of those students who have come under the influence of his teaching and his writings during the past thirty years, and he will always be remembered as having added new impulse both to geography and geology, especially in the University of Edinburgh, where his name and services are not likely soon to be forgotten. Professor James Geikie. 245 LIst OF SCIENTIFIC PUBLICATIONS BY PROFESSOR JAMES GEIKIE, F.R.S., ETC. 1866. 1867. 1868. 1869. 1870. 1871. 1872. 1874. 1875. 1876. 1877. ‘On the Metamorphic Lower Silurian Rocks of Carrick, Ayrshire”? : Quart. Journ. Geol. Soc., vol. xxii, pp. 513-34; Phil. Mag., vol. xxxii, pp. 154-5; Grou. Mae., Vol. II, pp. 321-2. ‘“On the Metamorphic Origin of certain Granitoid Rocks and Granites in the Southern Uplands of Scotland ’’: Grou. MacG., Vol. II, pp. 529-34. © ““On the Buried Forests and Peat Mosses of Scotland, and the Changes of Climate which they indicate’’?: Trans. Roy. Soc. Edinburgh, vol. xxiv, pp. 8363-84; Proc. Roy. Soc. Edinburgh, vol. v, pp. 635-7 ; GEOL. MaG., Vol. IV, pp. 20-3. ‘Hydrothermal Origin of certain Granites and Metamorphic Rocks ”’ GEOL. MAG., Vol. IV, pp. 176-82. ‘**On the Metamorphic Origin of certain Granites, etc.’’: ibid., Vol. IV, pp. 287-8. *“Qn Denudation in Scotland since Glacial times ’’: Trans. Geol. Soc. Glasgow, vol. iii, pp. 54-74; ibid., Vol. V, pp. 19-25. “Note on the discovery of Bos primigenius in the Lower Boulder-clay of Scotland ’’: ibid., Vol. V, pp. 393-5, 535-6. ** Additional Note on the discovery of Bos primigenius in the Lower Boulder-clay at Crofthead, near Glasgow’’: ibid., Vol. VI, pp. 73-8. “On the Age of the Stratified Deposits, with Mammalian Remains, at Crofthead, near Glasgow ’’: ibid., Vol. VII, pp. 53-7, illus. “‘ Carboniferous Formation of Scotland,’’ remarks on Mr. Croll’s letter: Trans. Geol. Soc. Glasgow, vol. iv, pp. 78-80 ; GEOL. MAG., Vol. VII, 1870, p. 298. ““On Changes of Climate during the Glacial Epoch’’: GEOL. MAG., Vol. VIII, pee 545-53 ; Vol. IX, Tei2 pp. 23-31, 61-9, 105-11, 164-70, 215-22, 254- 65. ‘The Carboniferous Formation of Suotlada ”: Trans. North Eng. Inst. Min. Engin., vol. xx, pp. 131-57; Trans. Glasgow Inst. Engin., vol. xiv, pp. 5-381. “4. EB. Térnebohm’s Theory of the Origin of the Swedish Asay”? GEOL. MAG., Vol. IX, pp. 307-9, illus. “On the Geological Position and Features of the Coal- and Ironstone- bearing Strata of the West of Scotland’’: Journ. Ivon. and. Steel Inst., vol. ii, pp. 8-24. ‘‘ On the Theory of Seasonal Migrations during the Pleistocene Period ’’: GEOL. MaG., Vol. X, pp. 49-54, illus. “The Antiquity of Man in Britain ’’ (a lecture): GEOL. MAG., Vol. X, pp. 175-9. ‘On the Glacial Phenomena of the Long Island or Outer Hebrides ”’ : Quart. Journ. Geol. Soc., vol. xxix, pp. 532-45; GEOL. MAG., Vol. X, pp. 377-9. ‘“Note on the occurrence of Erratics at higher levels than the Rock- masses from which they have been derived’’: Trans. Glasgow Geol. Soc., vol. iv, pp. 235-41; Gon. MacG., Dec. Il, Vol. I pp. 566-7. The Great Ice Age and its relation to the Antiquity of Man. pp. xxiii, 575, 17 pls., 8vo, London. Geology. (Chambers’ Elementary Science Manuals.) pp. 96, illus., 8vo, London. X “ Origin of Lake Basins”: GEOL. Maa., Dec. Ii, Vol. ILI, pp. 139-40. “*The Cheviot Hills”’: Gaod Words, vol. xvii, pp. 11-15, 82-6, 264— 70, 331-7, illus. Historical Geology. pp. vii, 94, 8vo, London and Edinburgh. “The Movement of the Soil- cap’’: Nature, vol. xv, pp. 397-8. ‘“The Antiquity of Man’’: ibid., vol. xvi, pp. 141-2. Letter to Mr. J. Gunn on the Glacial Beds of the East of England, Norfolk Chronicle, February 17. 246 1877. 1878. 1880. 1881. 1882. 1886. 1887. 1888. 1890. 1891. Eminent Living Geologists— The Great Ice Age and its relation to the Antiquity of Man. 2nd ed., pp. xxvii, 624, 19 pls., 8vo, London. ““ On the Glacial Phenomena of the Long Island or Outer Hebrides ’’ (2nd paper): Quart. Journ. Geol. Soc., vol. xxxiv, pp. 819-67, illus. ‘“On the Preservation of Deposits of Incoherent Materials under Till or Boulder-clay’’: GEOL. MAG., Dec. II, Vol. V, pp. 73-9, 287-8. (With A. C. Ramsay) ‘‘On the Geology of Gibraltar’? : Quart. Journ. Geol. Soc., vol. xxxiv, pp. 505-39. “Discovery of an Ancient Canoe in the Old Alluvium of the Tay, at Perth ’’: Scottish Naturalist, vol. v, pp. 1-7. “Changes of Climate in Post-Glacial times’’: ibid., pp. 193-203. ““Natural Rubbish Heaps’’: Proc. Perthshire Sci. Soc., vol. i, pp. 3-5. ‘“The Geological History of Perthshire’? (Presidential Address, March 3, 1881): ibid., pp. 17-21. “The Age of the Igneous Rocks of Iceland’’: Nature, vol. xxiv, pp. 605-6. Prehistoric Hurope: a Geological Sketch. pp. xviii, 592, 2 pls., 3 maps, 8vo, London. ‘“Notes on the Geology of Colonsay and Oronsay ’’: Trans. Glasgow Geol. Soc., vol. vi, pp. 157-64. “Climatic and Geographical Changes in Post-Glacial times’’: Proc. Perthshire Sci. Soc., vol. i, pp. 47-50. ‘“The Study of Natural Science’’ (Presidential Address): ibid., pp. 65-70. “The Intercrossing of Erratics in Glacial Deposits’’?: Scottish Naturalist, vol. vi, pp. 193-200, 241-54. ‘* On the Geology of the FeréeIslands’’: Trans. Roy. Soc. Edinburgh, vol. xxx, pp. 217-69, 4 pls.; Proc. Roy. Soc. Edinburgh, vol. x, pp. 495-501 ; GEOL. MaG., Dec. II, Vol. IX, pp. 278-9. ‘“The Aims and Method of Geological Inquiry ’’ (Inaugural Lecture, October 27, University of Edinburgh): Nature, vol. xxvii, pp. 44-6, 64-7, 8vo, Edinburgh. fl ‘“ Note on the occurrence of Drifted Trees in Beds of Sand and Gravel at Musselburgh ’’: Proc. Roy. Soc. Edinburgh, vol. xii, pp. 745-55. ‘“The Physical Features of Scotland’’: Scottish Geogr. Mag., vol. i, pp. 26-41, map. ‘““Leading Physical Features of Scotland’’: Ordnance Gazetteer of Scotland, vol. iii (Appendix), No. 2, 8vo, Edinburgh. ‘List of Hill Forts, Intrenched Camps, etc., in Roxburghshire on the Seotch side of the Cheviots’’: Proc. Berwick Nat. Club, vol. x, pp. 139-48. ““Mountains: their Origin, Growth, and Decay’’: Scottish Geogr. Mag., vol. ii, pp. 145-62. ““The Geographical Evolution of Europe’’: ibid., pp. 193-207. ‘“ Note on Sand-dunes of the Western Islands ’’: ibid., p. 474. ‘“The Natural History of Kinnoull Hill.’’ II. Geology: Proc. Perthshire Sci. Soc., vol. 7, pp. 235-7. Outlines of Geology. 8vo, London. : ‘“Geography and Geology’’: Scottish Geogr. Mag., vol. iii, pp. 398- 407, map. ‘Geology and Petrology of St. Abb’s Head’’: Proc. Roy. Soc. Edinburgh, vol. xiv, pp. 177-983, illus. Songs and Lyrics by Hewmrich Heine and other German Poets. 8yo. Outlines of Geology. 2nd ed., 8vo, London. “The Evolution of Climate’’: Scottish Geogr. Mag., vol. vi, pp. 59-78, 2 maps. ‘Glacial Geology ’’ (Presidential Address to Section C, Geology, of the British Association): Rep. Brit. Assoc. for 1889, pp. 551-64; GEOL. MaG., Dec. III, Vol. VI, pp. 461-77. ““On the Scientific Results of Dr. Nansen’s Expedition.’’ I. Geology : Scottish Geogr. Mag., vol. vii, pp. 79-86. 1892. 1893. 1894. 1895. 1896. 1897. 1898. 1899. 1900. 1901. Professor James Geikve. 247 “On the Glacial Succession in Hurope’’: Trans. Roy. Soc. Edinburgh, vol. xxxvii, pp. 127-49. ‘‘Supposed Causes of the Glacial Period’’ (an address): Trans. Edinburgh Geol. Soc., vol. vi, pp. 209-30. “The late Sir Andrew Crombie Ramsay, LL.D., F.R.S., etc.’ : ibid., vol. vi, pp. 233-40, portrait. Address to the Geographical Section of the British Association, Edinburgh, 1892: Scottish Geogr. Mag., vol. vii, pp. 457-79, map. ‘* Recent Researches in Pleistocene Climate and Geography ’’ (Abstract of a Lecture to the Royal Scottish Geographical Society, May 18, 1892): ibid., vol. viii, pp. 357-62. “Geographical Devélopment of Coastlines’’ (Presidential Address to Section E, Geography, of the British Association): Rep. Brit. Assoc. for 1892, pp. 794-810. Fragments of Earth Lore, Sketches and Addresses, Geological and Geographical: pp. vi, 428, 6 pls., 8vo, Edinburgh. ‘On the Glacial Period and the Earth Movement Hypothesis ’’: Trans. Victoria Inst. London, vol. xxvi, pp. 221-49. The Great Ice Age and its relation to the Antiquity of Man”’ : 3rd ed., pp. xxviii, 850, 18 pls. and maps, Svo, London. Review, GEOL. MAG., Dec. IV, Vol. II, pp. 29-38. ‘* Scottish Interglacial Beds’’?: Ghou. MAG., Dec. IV, Vol. II, pp. 283-4. ‘‘The Morphology of the Harth’s Surface’’: Scottish Geogr. Mag., vol. xi, pp. 56-67. ““ Classification of European Glacial Deposits’? : Journ. Geol. Chicago, vol. ili, pp. 241-69. ‘“The ‘Challenger’ Expedition’’: Scottish Geogr. Mag., vol. xi, pp. 231-43. Outlines of Geology. 3rd ed., 8vo, London. “«The last Great Baltic Glacier’’: Journ. Geol. Chicago, vol. v, pp. 325-39. ‘“Excursion from Bathgate to Linlithgow’’: Proc. Geol. Assoc., vol. xv, pp. 145-9. ‘““ Excursion from St. Monans to Elie’’: ibid., pp. 149-51. (Director) ‘‘ Long Excursion to Edinburgh and District—Bathgate Hills’: ibid., pp. 197-200. (Director) ‘‘ Long Excursion— Elie and St. Monans’’: ibid., . pp. 205-6. ““The Prehistoric Rock-shelter at Schweizersbild, near Schaffhausen ”’: Scottish Geogr. Mag., vol. xili, pp. 466-75. “The Tundras and Steppes of Prehistoric EHurope’’: ibid., vol. xiv, pp. 281-94, 346-57; Ann. Rep. Smiths. Inst., pp. 321-47. Harth Sculpture, or the Origin of Land-forms. pp. xvi, 320, 8vo, London. ‘“On the proposed Antarctic Expedition’’: Scottish Geogr. Mag., vol. xv, p. 256. ‘“A White-hot Liquid Earth and Geological Time’’: ibid., vol. xvi, pp. 60-7. ‘Mountain Structure and its Origin’’: International Monthly, vol. iii, pp. 17-41, 202-30. (With J. S. Flett) ‘‘The Granite of Tulloch Burn (Ayrshire) ’’: Rep. Brit. Assoc. for 1901, pp. 634-5 ; Grou. Mac., Dec. IV, Vol. IX, 1902, pp. 38-9. 1901-2. ‘‘Mountains’’: Scottish Geogr. Mag., vol. xvii, pp. 449-60 ; vol. xviii, 1902. 1903. 1905. 1902, pp. 76-84. Earth Sculpture, or the Origin of Land-forms. New edition, pp. 336, 8vo, London. Outlines of Geology. 4th ed., pp. 436, illus., Svo, London. Structural and Field Geology for Students. pp. xx, 435, 56 pls., 8vo, _ Edinburgh and London. 248 R. M. Brydone—Chalk Polyzoa. 1906. ‘‘Prom the Ice Age to.the Present’’: Scottish Geogr. Mag., vol. xxii, pp. 397-407. ‘Qn the so- -called ‘ Postglacial Forntations’ of Scotland’’: Journ. On Geol. Chicago, vol. xiv, pp. 668-82. »1907. -'! Old Scottish , Voleanoes’’: Scottish Geogr. Mag., vol. xxiii, pp. 449-63. : ; ‘‘ Tate Quaternary Formations of Scotland”? : -Zeitschr. fiir Gletscher- ‘ kunde, Bd. i, pp. 21-30, fig. 1908. Structwral and Freld Geolatiy for Students, ete. 2nd ed., pp. 443, 56 pls., 8vo, Edinburgh and London. 1909. Harth Sculpture, or the Origin of Land- forms. 2nd ed., 8vo, London. ‘*Calabrian Earthquakes ’’: Scottish Geogr. Mag-, vol. xxv, pp..113- 26, figs. 1911. ‘‘ The Mer ticchtins and Origin: of the Alps’’?: ibid., vol. xxyii, pp. 393-417, figs. ; 1912. Structural and Field Geology for Students, etc. 3rd-ed., pp. 452, 69 pls., 8vo, Edinburgh. a the) Deeps’. of the Pacific Ocean and their Origin ’’: Scottish Geogr. Mag., vol. xxviii, pp. 113-26, map.. Memoirs of the Geological Survey of Scotland (partly contributed to by J. Geikie). Sheet Memoirs: 1869; Sheet 7 (Ayrshire, South- Western District), Sheet 14 (Ayrshire, Southern District), Sheet 24 (Peeblesshire) ; 1872, Sheet 22 (Ayrshire, North part); 1873, Sheet 23 (Lanarkshire, Central Pistigel 1879, Sheet 31 (Stirling- shire). Il:—Norrs oN NEW OR IMPERFECTLY KNowN CHALK Potyzoa. By R. M. BRYDONE, F.G:S. . (Continued from the May Number, p. 199.) (PLATE VIII.) VICULARIA. of what I have called the Leswewri-type are not confined to Membranipora. There are at least two species provided with them which come nearer to Seméeschara. SEMIESCHARA LABIATULA, sp. nov. (PI. VIII, Figs. 1-4.) Zoarium always adherent. Zoecia subpyriform, with separate side walls which are broad and pass gradually down into the front wall; apertures large and sub- triangular, with the apex flattened owing to the development of a slight internal front ‘wall, fairly straight sides with a tendency to bulge inwards towards the top anda lower lip always more or less convex with an upturned tip which catches the lght and is very useful for rapid recognition; these convexities are most marked in the later forms and may be so pronounced as to make the aperture definitely trifoliate (Fig. 4). Oecia abundant, narrow helmet- aay swellings of the foot of the succeeding zocecium. Avicularia abundant and typical; aperture broadly elliptical, but with a distinct tendency toassimilate itself in general outline to the zocecial aperture (especially in the lower lip, which may be strongly convex), the lower section nearly or quite equal in size to the upper; the infold of the side wall sudden, with a concave edge; avicularia of a modified form looking as if a small zocecium had been set into the aperture of a normal avicularium occur very sparingly (Fig. 2), Grou. Mage., 1913. PLATE VIII. R. M. Brydone, Photo. Bemrose, Collo. Chalk Polyzoa. R. M. Brydone—Chalk Polyzoa. 249 The species occurs rarely and of small size in the upper subzone of the zone of O. pilula, and becomes fairly common in the restricted zone of A. quadratus but remains small; at Trimingham jit is abundant and distinctly larger, occasionally attaining a very con- siderable size. I have no specimens from intermediate horizons. The avicularia enable it to be distinguished at once from such species as Cellepora Villierst, D’Orb.,1 or the earlier figures of Eschara Delarueana, D’Orb.,? to which zocecially it bears some resemblance. SEMIESCHARA occLUSA, sp. nov. (Pl. VIII, Figs. 5-8.) Zoarium always adherent. Zoecia long and pyriform, with separate side walls; apertures more or less semicircular, with strongly rounded corners and slightly flattened at the head, by the development of a tiny internal front wall; imperforate lids which completely seal up the aperture are preserved here and there all over the zoarium and abundantly among the early zocecia. ; Oecia abundant, narrow helmet-shaped swellings of the foot of the succeeding zocecium. . — Avicularia apparently very similar to those of S. Jabiatula, but with the infold of the side wall in such low relief that it is very difficult to make out its details (the definiteness of the illustrations has largely accrued in the process of reproduction); apertures normally enlarged copies of the zocecial apertures, but with a distinct tendency to rectilinear outlines, which sometimes goes so far as to turn them intorude hexagons; modified avicularia similar to those of S. labiatula, but much less conspicuous, are fairly common. ‘he species is common at Trimingham, especially in the lowest beds exposed there, and probably therefore has a further range downwards, and as this range does not extend to the Weybourne horizon it may possibly be of assistance in identifying Chalk intermediate between the Trimingham and Weybourne horizons. SemipscHara Muwnpssterensis, mihi.® (Pl. VIII, Fig. 9.) The original figure of this species was inaccurate, and as it is near enough to S. Jabiatula for comparison I give a photograph of the type. It will be seen that the avicularia are constructed on the same general plan of infolded side walls as the Zesweurt-type, but cannot be included in the latter, as they are not conspicuously larger than the zocecia. I have found rather primitive specimens of this species very occasionally in the mucronata-chalk of the Isle of Wight and Hants. SemrescHara Canuz, mihi? (PI. VIII, Figs. 10, 11.) EscHara Rower, mihi? (Pl. VIII, Fig. 12.) I take this opportunity of supplementing the diagrammatic original figures of these species by photographs of specimens lending them- selves to photography more kindly than the types. In the case of S. Canui, Fig. 10 shows that this species possessed ocecia in the shape of large, flat, rather inconspicuous swellings, 1 Pal. Frang., tom. v, p. 407, pl. 605, figs. 8, 9. 2 Tom. cit., p. 105, pl. 602, figs. 6-8. > GEOL. MaG., 1906, pp. 289-300. 250 Rev. 0. Fisher—Rigidity of the Earth. a perfect one and one unroofed being visible. They are of rare occurrence. The avicularian aperture has a semicircular upper lip with unbroken curve when perfect, as shown by the original figure and Fig. 11, but the regularity of the notches shown in Fig. 10 suggests a median line of weakness, perhaps indicating that the species started with a notch there, the filling up of which was not yet fully consolidated. In the case of #. Rowe: it is clear that the outline of the avicularian aperture was misrepresented in the original figure, and that it has a straight lower lip and diverging sides and a convex upper lip, and that the lower lip bears a long slender denticle. EXPLANATION OF PLATE VIII. (All figures X 12 diams.) Fie. 1. Semeschara labiatula. Zone (restricted) of A. quadratus, Upham, Hants. Fics. 2, 3. 8S. labiatula. Trimingham. Normal specimens. Fic. Aes Joie it Trimingham. Small form with trifoliate apertures. Fies. 5-8. SS. occlusa. Trimingham. Fie. 9. S. Mundeslerensis. Trimingham. Type-specimen. Fies.10,11. S.Canwi. Trimingham. Fic. 12. Hschara Rowet. Trimingham. I1I.—On tae Rieipiry or tHE Earru, and on Coronet Burrarn’s THEORY OF THE HiMaAtayYas. By the Rev. O. FISHER, M.A., F.G.S. N the April number of this Magazine a review appeared of Colonel Burrard’s memoir! on the origin of the Himalaya Mountains. The writer, Sir T. H. Holland, in it refers to a paper of mine originally published in the Phil. Mag.,? and subsequently in an amended form as Appendix No. 1, 1905, Indian Survey Papers, professional vol. xviii. I shall be glad to make a few remarks upon the subject. After duly crediting me with having partially anticipated the results now obtained by the Survey, by calculating the deflection of the plumb-line in North India which would follow from my theory of mountain compensation by a ‘root’ extending to a depth of about 29 miles, the reviewer continues—“ The variations now observed are, however, more violent than those expected by Mr. Fisher, for the northerly deflections of the plumb-line decrease to zero at a distance of about 15 instead of over 60 miles from the visible foot of the hills.” I would reply that I have not caleulated the deflection at 15 miles, and it is not safe to guess a priort what it would be. The numerical calculation for a given distance is tedious, and I could not now undertake it. Though Sir T. H. Holland appears to admit that my theory (or rather Airy’s) of mountain roots goes some way to account for the observed deflection, he nevertheless adds that it does not ‘‘ march”’, like Colonel Burrard’s, ‘‘ with the growing belief in a solid earth.”’ 1 Survey of India, professional paper No. 12, Calcutta, 1912. 2 Phil. Mag., January 7, 1904. 3 In the Phil. Mag., p. 24, in the formula for the attraction of the plateau, there is a misprint. After the first bracket insert «. Rev..0. F isher—Rigidity of the Harth. 251 This statement possibly refers to Professor Hecker’s observations on the bodily tides of the earth. I understand the word ‘solid’ as opposed to ‘fluid’, not’ as equivalent to ‘rigid’. Is it not possible that there may be a liquid substratum to the earth’s crust, and the earth may nevertheless be rigid with respect to the external disturbing forces of the attraction of the moon and sun as evidenced by tides ? By way of illustration, we are quite unconscious of the rotation of the earth on which we stand. but if we could observe the earth with a telescope from the moon, the effect of rotation would be very marked by the rapid passage of objects near our equator across the field of view. Is it not possible that the earth’s rotation may impart ‘to it a ‘gyroscopic’ quasi rigidity, which may enable it to withstand the deforming influence of external’ forces, although at the same time forces internal to the earth will be unaffected by it. Professor Perry, in his little book on spinning-tops, illustrates how ‘‘rapid motion gives a peculiar quasi rigidity to flexible and even to fluidthings. Here,” says he, ‘‘is a disk of quite thin paper ; and when I set it in rapid rotation you observe that it resists the force exerted by the blow of my fist as if it were a disk of steel. Hear how it resounds when I strike it with a stick. Where has its flexibility gone?” In the highly interesting and instructive paper which Sir G. H. Darwin read at the Geodetic Conference of 1909, giving an account of Hecker’s observations of the tidal deformation of the earth, he reproduced Hecker’s curve, which represents the rigidity both in north and south, and east and west directions. The radius of this curve is proportional to the rigidity, and shows in a remarkable manner that the rigidity is much greater in the east and west direction than in the north and south. And in the discussion that followed Darwin said that he ‘‘ considered as worthy of consideration Professor Hecker’s explanation of the remarkable absence of symmetry in the path of the vertical” (that is, the difference of rigidity in different directions, Hecker’s explanation depending upon the geographical situation of Potsdam), ‘‘ but he suggested an alternative possibility. The curve was much compressed in the north and south direction, showing that the earth has much greater rigidity east and west than north and south. It is possible to explain this to some extent by the earth’s rotation. Lord Kelvin introduced the idea of ‘gyroscopic’, that is of greater rigidity east and west due to rotation. Whether this is a sufficient explanation cannot be said, because no one has succeeded in solving completely the gravitation problem of a rotating elastic globe’’;! nor yet, I believe, of a partially liquid one. Although it may be that rotation imparts a greater rigidity in the equatorial direction, yet Professor Perry’s experiment quoted above shows that there is great rigidity imparted in the axial direction also. If rotation is competent to impart the needful excess of rigidity, it may be pertinent to ask, why not the whole of it? I do not remember ever to have seen changes of level accounted for on the hypothesis of a solid earth. There also appears to be some 1 Nature, vol. lxxxi, p. 427, October 7, 1909. 252 R. H. Rastall—Minerals of Barrington Bone-bed. reason for believing that alterations in the force of gravity are even now going on at Dehra Dun in India, which would indicate internal movements of mass incompatible with solidity.’ Colonel Burrard’s theory, of a rift in the sub-crust along the area of low density skirting the mountain range, will no doubt receive the consideration which the high position of its author demands for it; but it is obvious that there are difficulties. He appears to believe that the sub-crust beneath the mountains contracted upon itself, and in being shortened laterally became thickened vertically, and rose up into a mountain range, leaving a rift where it parted from the adjacent sub-crust. If it was in a state of tension, it is conceivable that a rift might have been formed, and that it might have contracted upon itself until the tension was relieved. During this part of the process it would have decreased in volume and become more dense. Then it seems to be supposed that the process of lateral contraction continued, and, contrary to what might be expected, it became less dense. A decrease of mass below corresponded to the protrusion of the mountains above. The material remaining below thus became less dense than the mountains which it pushed up, and that in spite of the pressure. Thus partial isostacy would result. These movements being supposed to have gone on in a sub-crust, any rift formed by them would appear to have been more likely to open from below, and to have been filled with heavy material rather than with sediment from the surface. Rifts have been abundantly formed among the older rocks, but they are never empty, but filled with some intrusive material or mineral veins, usually of a denser character than the country rock. An empty rift would be an anomaly. In any theory of a mountain range allowance must be made for the enormous amount of material which has been denuded from it; in the case of the Himalayas, the Sewalik range, the alluvium of all the Indo-Gangetic plain, besides what has been carried out to sea by rivers. Elevation in compensation of this waste is continually going on, and it is probable that it is this which is the cause of the frequent earthquakes that occur in the district. TV.—Tue Mivnerats oF THE Barrineron BonE-BeED. By R. H. RASTAuL, M,A., F.G.S. NE of the most important and most interesting features of the geology of the Cambridge district is the deposit at Barrington, so widely known for its richness in mammalian remains. This bone-bed has been described many times, and the literature is large. Most of the descriptions, however, confine themselves chiefly to the organic contents, mentioning briefly the character of the larger stones and pebbles, and saying little or nothing about the nature of the finer matrix in which these are embedded. The author has been for some time past engaged in the study of the mineralogical composition of the sands and gravels of Pleistocene 1 See Colonel Burrard’s paper, Phil. Trans., ser. A, vol. ecv, 1905. Also Nature, vol. xci, p. 148, 1905. ) R. H. Rastall—Minerals of Barrington Bone-bed. 253 and Recent age in this district, with a view to ascertaining whether the character and possible derivation of the smaller mineral grains might throw any light on the correlation of these puzzling deposits. Some of the results have been already published,’ while other groups are still under investigation. Since the Barrington Bed is so widely known, and so peculiar in character, it seemed advisable to accord it separate treatment. The earliest detailed description of the lithological character of the bone-bed appears to be that given by the Rev. O. Fisher in 18797; it is as follows :— ‘‘The materials of which the bone-bearing deposit consists are peculiar. The matrix isa grey sand with a slight admixture of clay. The pebbles consist of flint in subangular pieces of no great size, sometimes ochreous, sometimes grey, sometimes black. These are not rounded, but have their surfaces worn, polished, and the angles rubbed off. There are rolled lumps of Chalk-marl and a considerable admixture of ‘coprolites’, as might be expected, seeing that the coprolite-bed is abraded by the deposit itself. The remaining pebbles are well-rounded pieces of crystalline rocks, consisting of quartz, quartzite, syenite, jasper, and trap. ‘These old rocks contribute a large part of the pebbles, so that the material cannot be called a flint-gravel, in that it appears to consist of the least destructible parts of the Boulder-clay, mixed with materials from the Chalk-marl and Greensand. “:> bearing appendages 40 of mid-body. Sesments of hind-body with no appendages. Post-anal tail-spine or telson. | Fic. 2. Lower or ventral aspect of Hurypterus Fischer, from the Upper Silurian of Oesel in the Baltic. The drawing made from G. Holm’s original figure. Nat. size. Reproduced by permission of the Trustees of the British Museum (Natural History). 296 Dr. H. Woodward—The Position of the Merostomata. Hemiaspis limuloides from the Lower Ludlow, Shropshire (see Quart. Journ. Geol. Soc., vol. xxi, pp. 482-92, pls. xii, xiv). In 1866 I commenced a monograph of the British Fossil Crustacea of the order Merostomata in the annual volumes of the Palseontographical Society, completed in 1878, in which fourteen genera and eighty-three species are recorded and all the then known British species described and figured. From 1878 to 1911 more than a hundred contributions have been added to our knowledge of this truly wonderful group. Special reference should be made to the remarkable work of G. Holm? on KLurypterus Fischert from the Upper Silurian of Root-si-kul, in the Baltic island of Oesel. Professor J. M. Clarke writes: ‘‘ Taking for the subject of his investigations the same wurypterus fischeri from Oesel, that had been already studied by Nieszkowski and Schmidt, he succeeded by most clever manipulation in isolating the chitinous test of the animal, which in this locality is not metamorphosed into a carbonaceous film, as in other deposits, and was able to elaborate its organization in such detail that 2. fischeri has really become the most completely known of all extinct animals, and our exact knowledge of it is quite comparable with that of its recent relatives. ‘By comparison with Zimulus, the differences in the appendages of the first and second sternites were referred to their proper sexes. Many details of structure were discovered, such as the minute chelicere, the epicoxite of certain coxal segments, the endostoma of the posterior margin of the mouth, the connection of the metastoma with the gnathobase, the clasping organ of the second endognathite of the male, the originally composite nature of the metastoma, corresponding to the chilaria of Zemulus, and the interior tubular processes of the female opercular appendage. His work has served to bring out with still greater force the numerous homologies and consequent close relationship of the Eurypterids to Limulus.” Figs. 1 and 2 give actual reproductions of this remarkable specimen, showing the dorsal and ventral aspect (pp. 294-5). To those who are interested in the study of these ancient forms, it may be desirable to mention that a model of Hurypterus Fischert (by Mrs. Blackman) is exhibited in the Zoological Gallery of the Natural History Museum, Cromwell Road, 8. W. Foremost of the long list of modern investigators, and following, as Director of the New York State Museum, in the position so long and honourably held by Professor James Hall at Albany, N.Y., stands the name of Professor John M. Clarke, Ph.D., D.Se., LL.D., For. Corr. Geol. Soc. Lond., and one of the most able and energetic geologists and paleontologists in North America. Assisted by Dr. Rudolph Ruedemann, Professor J. M. Clarke issued last year (1912) from the State Museum, Albany, two grand volumes entitled Memoir 14, Zhe Kurypterida of New York (one volume of text, pp. 440 quarto, with 121 text-figures, and one volume of 88 plates, several of which are large folding plates, and pp. 441-628, 1 “ Ueber eine neue Bearbeitung des Hurypterus Fischeri, Hichw.’’ : Acad. Imp. Sci. Bull. St. Pétersbourg, sér. V, iv, 369, 1896; Geol. For. i Stockholm For., Bd. xxi, p. 83, 1899. Dr. H. Woodward—The Position of the Merostomata. 297 of explanations of plates, with a full index at the end). It is delightful to find in these massive tomes such a grand collection of materials relating to the American Merostomata, which the authors have themselves brought together so carefully and studied and described with so much patience and acumen, nor has the contemporary foreign literature on the group been neglected, for every writer will find his work and observations duly recorded and acknowledged. The volumes just issued by the New York State Museum make us acquainted with no fewer than sixty-six American species, ranging from Professor Walcott’s Beltana Danai, Echinognathus Clevelandi, and Strabops Thatchert of Cambrian age to the Huryptert of the Coal- measures. No Limuli are recorded, but they are accepted as next of kin to the Eurypterids on the one hand and to the Scorpions on the other. Of actual complete forms of American Kurypterids known and figured by Clarke and Ruedemann in their memoir (vol. ii), may be cited— Strabops Thatcheri, Beecher. Upper Cambric. ES remupes, De Kay. Siluric. #. lacustris, Harlan. Bertie Waterlime. ‘ ranilarva, Clarke. Lockport Limestone. H. Dekayt, Hall. Waterlime. EH. microphthalmus, Hall. Manlius Limestone. #H. Maria, Clarke. Shawangunk Grit. H. Kokomoensis, Miller & Gurley. Waterlime. Husarcus scorpionis, Grote & Pitt. Waterlime. H. Newlini, Claypole. Waterlime. (Size, 26 x 13 inches.) Dolichopterus macrocheirus, Hall. Waterlime. Stylonurus longicaudatus, Clarke. Waterlime. S. excelsior, Hall. Catskill Beds. (56 inches long.) S. cestrotus, Clarke. Shawangunk Grit. S. myops, Clarke. Shawangunk Grit. Hughmuilleria socialis, Sarle. Pittsford Shale. A. Shawangunk, Clarke. Shawangunk Grit. Pterygotus Buffaloensis, Pohlman. Bertie Waterlime. P. macrophthalmus, Hall. Bertie Waterlime. By by To these must be added nearly fifty species described and figured from more or less perfect remains, many of which, however, add greatly to our knowledge of structural details of the group. The plates are admirably executed and show the minutest features of each species. The eighty-eighth and last plate gives an enlarged figure ( x 7) of Proscorpius Csborni, Whitfield, Upper Silurian, affording a convenient comparison with Hurypterus and other Merostomes. The following fifty species are arranged in order from the Cambrian to the Coal-measures :— Beltana Danai, Walcott. Greyson Shales, Montana. Echinognathus Clevelandi, Walcott. Utica Slate, Oneid Cap. Hurypterus megalops, Clarke. Frankfort Shale. Hf. pristinus, Clarke. 36 H. stellatus, Clarke. si9 Eusarcus triangularis, Clarke. 35 Ei. (2) longiceps, Clarke. 5p Dolichopterus frankfortiensis, Clarke. -,, D. latifrons, Clarke. 28 Hughmilleria magna, Clarke. 39 298 Dr. H. Woodward—The Position of the Merostomata. Pterygotus nasutus, Clarke. Frankfort Shale. P. prolificus, Clarke. 4 Stylonurus (?) limbatus, Clarke. ay Megalograptus Welchi, Miller. Richmond Group. Hurypterus promimens, Hall & Clarke. Clinton Beds. H.sp. Arisaig, Nova Scotia. Drepanopterus longicaudatus, Clarke. Lockport Limestone. Hurypterus Boylei, Whiteaves. Elora, Ontario. H. Puttsfordensis, Sarle. Pittsford Shale. Stylonurus multispinosus, Clarke. Pittsford Shale. Hughmilleria socialis, var. robusta, Sarle. Pittsford Shale. Pterygotus Monroensis, Sarle. Pittsford Shale. Husarcus cicerops, Clarke. Shawangunk Grit. Dolichopterus otisius, Clarke. A D. stylonuroides, Clarke. ie Stylonurus cestrotus, Clarke. os = sp. a, sp. B, sp. 7. = Diams globiceps, Clarke. Hurypterus lacustris, var. pachychir us, Hall. Bertie Waterlime. EH. pustulosus, Hall. Bertie Waterlime. Dolichopterus siluriceps, Clarke. Bertie Waterlime. D. testudineus, Clarke. ae Pterygotus Cobbi, Hall. 5 P. grandis (Pohlman). P. Atlanticus, Clarke. Devonic. P. sp. ae Gaspé, Quebec. Hurypterus pulicaris, Salter. +3 EHurypterella ornata, Matthew. ae New Brunswick. Stylonurus (?) Wrightianus (Dawson). Portage Sandstone. S. Beecheri, Hall. Catskill Beds, Penn. Hurypterus approximatus, Hall & Clarke. Waverly Beds. H. Mazonensis, Meek & Worthen. Coal-measures. H. Mansfieldi, C. EK. Hall. Coal-measures, Penn. H. Pennsylvanicus, C. KE. Hall. ae E. potens, C. E. Hall. at EH. stylus, J. Hall. ar Since the important contributions made to this group by Professor James Hall (1859-62) all zoologists have accepted the correctness of his correlation of Limulus with Hurypterus, Pterygotus, and their allies. But another question was raised by Sir E. Ray Lankester (in 1881)! as to whether Limulus was indeed a true Crustacean after all, but should be rather considered as an aquatic Arachnide. If we make a brief comparison of the characters of the three great groups of Limulide, Kurypteride, and Scorpionide, we shall be str uck by the family resemblances they offer. In Limulus the body, although compressed, represents by its paired appendages the concealed presence of a common number of coalesced segments. The head-shield bears upon its upper surface both ocelli and compound eyes. On the under side is the mouth with six pairs of chelate appendages, the bases of which serve as mouth organs (save the first pair) and for prehensile or walking-legs at their distal extremities. The mid- and hind-body are coalesced and bear on the under side six broadly expanded and united pairs of plates, the first pair carrying the ovaries and genital pores, the five pairs following 1 * Timulus an Arachnid ?’’: Quart. Journ. Mier. Sci., N.S., xxi, p. 609. Dr. H. Woodward—The Position of the Merostomata. 299 being gill-bearing (branchie). The hind-body has no limbs, but to it is articulated a long bayonet-shaped tail-spine (or ‘ telson’). In Eurypterus the head-shield is smaller than in Limulus and the body much more elongated and the segments free and movable. The head-shield bears upon its upper surface both ocelli and compound eyes. On the under side is the mouth with six pairs of chelate or simple maxillipeds, the first two pairs serving as tactile organs (cheliceree and antennz), then three simple spinose limbs, and lastly -a pair of larger swimming appendages with well-developed basal jaws and a central oval plate or metastoma. The mid- and hind-body are not coalesced (as in Limulus), but the segments are distinct and flexible and adapted to a swimming existence. On the under side, immediately behind the head (as in Limulus), is a broadly expanded plate, the operculum carrying on its inner surface the paired ovaries and genital pores, followed by three or more broad plates carrying the gill-packets or branchie. The hind-body is destitute of appendages, but to its last segment is articulated a long and slender telson or tail- spine, which in Pterygotus is broad and spear-shaped at its extremity. In Scorpio the head is oblong in form and bears on its upper surface ocelli in the centre and groups of eyes at the anterior angles. On the under side is the buccal orifice with short chelicere in front, and a pair of large chelate pedipalps, followed by four pairs of simple or clawed oral appendages, used in terrestrial locomotion in the living species, and for assistance in swimming in some of the fossil aquatic forms. The mid-body bears a pair of comb-like organs, and also the organs of reproduction (genital openings).- The segments following carry three or more ors of gill-packets or tracheal openings (respiratory organs) adapted for terrestrial.existence in the living species, and for aquatic life in the early fossil forms. The six following segments forming the hind-body are narrow and elongated without appendages; to the last segment is articulated the ‘telson’ or tail-spine, which in modern Scorpions serves as a sting or poison-organ. We know that Zimulus has always been aquatic in its habit, and in the earlier forms the segments of the mid- and hind-body apparently were mostly free and movable, and adapted for swimming, as is the case with the young stages in the development of the living king-crab.1 It is the opinion of Lankester, of Pocock, of Laurie, and others that the early Silurian Scorpions (Palgophonus, Proscorpius, etc.) were aquatic forms, their remains having been found in truly marine deposits. The correlation of Zamulus with such forms as Hurypterus and Pterygotus naturally suggested a close affinity with the Scorpionide, and it is also of interest to note that Scorpions have been met with in America, in Scotland, and in the Baltic area in marine strata ‘associated with Hurypterus, Pterygotus, and Limulus. It is an astonishing fact that two of these types, Scorpvo and Limulus, should have persistently survived through all the accidents and changes of living things, from Silurian times to the present day, and that both 1 See A. S. Packard, ‘‘Development of Limulus polyphemus’’? (Mem. Boston Soc. Nat. Hist., 1870, p. 154); Anton Dohrn, Jenaische Zeitsch., v, p. 6, 1871; A. Agassiz, Amer. Journ. Sci., ser. II, xv, 75, 1878. 300 H. L. Hawkins—The Lantern of Perischodomus. ‘should be found distributed over so vast a geographical area among the living fauna of our globe. They may indeed justly claim to be considered as amongst the oldest living races and the marvels of the animal world. It is true that the other great group to which they are so closely related, the Eurypterida, has passed away, not having survived beyond the Carboniferous epoch ; but as this group certainly appeared earlier on life’s scene, it doubtless impressed its mark upon other types of Arthropoda, and quite possibly was the great ancestor of the Scorpions and King-crabs in earlier Cambrian times. IV.—Tue Lantern or PERISCHODOMUS. By HERBERT L. Hawkins, M.Sc., F.G.S., Lecturer in Geology, University College, Reading. OME years ago Mr. D. M. S. Watson and I collected, from the Carboniferous Limestone of Clitheroe, Lancashire, a considerable series of Echinoids. One slab of the limestone (measuring 16 X 12 cm.) is covered by a great number of disjointed plates and other skeletal fragments of a large Perischodomus, probably P. bisertalis, M’Coy. Dr. R. T. Jackson refers to the specimen (Phylogeny of the Echint, p- 406), and, as the jaw fragments show features not hitherto CU LM) Fies. 1, 2.—Perischodomus biserialis (?). Alveolar and interpyramidal views of maxille. described for the genus, it seems advisable to give a brief account of it. The preservation of a compass is a point of special interest, as these delicate structures are known in very few eases in the fossil state. Maxille (Figs. 1, 2).—Fragments of eight of the ten maxille are preserved, three of them being very well shown. The two figured examples show the interpyramidal and alveolar surfaces completely. They agree absolutely in measurements, as do all the other fragments as far as can be ascertained. Symphysial margin 16, dental slide 16, H. L. Hawkins—The Lantern of Perischodomus. 301 total length 24:4, greatest width (margin of epiphysis) 12°3 mm. As is usual among Paleozoic lanterns, the maxille are very wide (measured radially) and have the interpyramidal faces considerably curved. The convexity of the outer surface (at the symphysis) is such that the tooth must have projected almost at right angles to the line of the upper part of the pyramid—perhaps working horizontally. None of the specimens show the outer face completely, but the indications point to its being similar in proportions to that of Archeocidaris neret (cf. Jackson, op. cit., pl. x, fig. 6). - Epiphyses (Fig. 3).—Two of these ossicles are shown, one being almost complete and exposed from the side of its articulation with the maxille. Its radial width is 12°2mm., and its height at the outer edge is 10°4mm. Its inner height is only 4:2mm. There is a slight concavity on the free part of the surface, and a very low knob at the inner and upper corner. The articulation surface is irregularly and coarsely roughened. _ Compass (Figs. 4, 5).—One compass exists on the slab, exposed from the side and upper surface. It is broken, apparently along the Perischodomus biserialis (?). Fic. 3. Epiphysis, articular surface. Fias. 4,5. Compass, upper and side views. suture by which all compasses are traversed, and has been pressed into one of the interambulacral plates. A scar is left on the plate where the compass has been destroyed, and this additional part is. indicated on the figures by shading. The total length, as far as can be ascertained, is 10°5 mm. (measured along the chord). From the outer-muscle prominence to the circular-muscle prominence is 4mm. From the outer extremity to the fracture (?suture) is 6mm. The height at the inner (broken) end is 2.4mm. ‘The compass is flattened and broad (viewed from above) in the outer part, but inward from the cross- fracture becomes compressed and narrow. ‘This feature has probably been exaggerated by crushing. The bifurcation of the outer end is not very marked, although the prominences project laterally to a considerable amount. The most striking features in the compass are the supports for the circular muscle. These project even further outwards than the external supports, as shown in Fig. 4. As far as I am aware, no such 302 G. C. Robson—On Helminthochiton. prominence in this region of the compass is met with in any other Echinoid, fossil or recent—in fact, the usual articulation for the circular muscle is rather.a depression than an elevation. The compass of Pholidechinus (Jackson, loc. cit., pl. xxvii, fig. 5) shows ncething comparable, but is not very perfectly preserved. That of Archeocidaris rossica (loc. cit., pl. xii, figs. 1, 2) is particularly slender and smooth in outline. The precise function of the circular muscle is not known. It is therefore idle to speculate as to the reasons for this extraordinary development in the compass of Perischodomus. It suffices to record that it is unique among known forms. Tooth.—A small fragment of the distal end of a tooth is shown on the specimen. It is 58mm. long (as far as exposed), and 4°25 mm. broad before it begins to taper. It is, as usual, Aulodont in character, and the groove is shallow. The point is broken away. The specimen is now in the Manchester Museum, registered No. L. 8722. V.—HELMINTHOCHITON 2&QUIVOCA, N.SP., LowreR ORpovIcIAN, Bouemia. By Guy C. Rosson, B.A. (Published by permission of the Trustees of the British Museum.) ‘| \HE species described in this paper is based on specimens acquired for the Geological Department of the British Museum in 1912 from Professor C. Kloucek, of Prague, who collected them from the upper portion of D,y(=Arenigian) at Sarka and Malé Prilepy. The fossil was referred in the first instance by Professor Klouéek to ‘“«Chiton sp.?”’ and the result of the present investigation has been to uphold the reference to the Polyplacophora, though the precise generic status must remain’ vague. The remains themselves consist of a number of imprints of shell- fragments in portions of two separate ironstone nodules, and have been studied by means of gutta-percha squeezes. In the nodules the imprints are arranged in a crude linear series of indeterminate form, while several of them lie apart from the main series. Two only have the appearance of being applied to one another in the characteristic Chiton fashion. A large number of the fragments are too amorphous to justify the expenditure of time in studying them. We therefore direct attention to six pieces, the shape and texture of which are sufficiently well characterized to enable one to form an opinion of their nature. These, however, are in no case connected with each other, nor do they afford any grounds, save those of general resemblance, for referring them to the same individual. A typical fragment would consist of a single plate bent into halves, at an angle of 90° or less, along a line occupying the sagittal axis. At their line of junction the two halves form a sharp carina, while at one end of the plate the outer angles of the sides are produced, leaving a median V-shaped notch or emargination. There is probably a corresponding median projection at the other end, but of this it is impossible to be certain. On the surface of the plates a diagonal G. O. Robson—On Helminthochiton. 303 sculpture is seen extending as two or three faint grooves from the carina at one end to the free angle at the other (emarginate) end. Under a moderate power of the microscope, but scarcely visible with . a hand lens, a faint concentric striation, ike growth-lines, is visible running parallel to the outer margins. The valves themselves are very small, a typical example measuring 5 mm. along the carina, and 3°5 mm. from the carina to the inferior free border. It is impossible to distinguish any other characters than these. Thus it will be seen that the data available for determining the nature and affinities of this fossil are very scanty. The bent plates with diagonal and concentric sculpture suggest a Chiton more than any other form, and we shall see that one character at least—the (posterior) emargination—suggests a definite genus of Chiton. One or two of the plates look superficially lke the carinals of an unorna- -mented Cirripede, though there is nothing beyond the carination to endorse this view, and Messrs. Cowper Reed and Withers have not upheld it after examining the specimens. Helminthochiton equivoca, .x 6. Lateral view of plates. a—a, median line; 6, the posterior emargination. Reference to the literature of Ordovician and Silurian inverte- brata has yielded only one genus to which this fossil might be referred, viz. Salter’s Helminthochiton (1846-7) as redefined by de Rochebrune (1883). Through the kindness of Mrs. Robert Gray and Dr. R. F. Scharff it has been possible to make a careful study of H. grayie, Woodward (1885), from the Starfish Bed of the Drummuck group of Girvan (Ashgillian age), and of HZ. griffithit, Salter, from the Silurian (Upper Llandovery) mudstones of Galway. The type of the latter from the National Museum, Dublin, was lent by Dr. Scharff, while ample material representative of the former was lent by Mrs. Gray. The Bohemian fossil seems to be adequately distinguished from the Girvan form. The only feature in common between them is 304 G. C. Robson—On Habovinthocnin. the nature of their sculpture. But while in H. grayi@ both the concentric and diagonal markings are prominent and clearly defined, in the Bohemian form they are very faint and almost imperceptible, and withal very different in character. Indeed, with regard to H. grayia, Mr. Cowper Reed’s doubts (1907) as to its true zoological position seem fully justified, and one would not be in any way surprised if it were to be at a future date removed from the Amphineura altogether. On the other hand, there is a significant point of agreement between the Bohemian fossil and #. griffithi in the (posterior) excavation above alluded to. In addition the valves are short and deep in both species. On these grounds the new form may provisionally be placed in the same genus as H. grifthi. It is distinguished from that species by the possession of concentric and diagonal sculpture, and the more acute angle which the two halves of each plate form with each other. So far as I can discover, no Chiton has been recorded from the Lower Ordovician before. Billings’ problematic Chiton canadensis (1865) is apparently the oldest-known member of the family up to the present. This form was obtained from the Black River Limestone of Llandeilian age (= Middle Ordovician). If H. @guivoca should retain the classificatory position here assigned to it, it will rank as the oldest-known representative of the Amphineura. The early Paleozoic Chitons would appear to have been small animals, possessed of an armature of thin valves, probably lacking insertional lamine. In addition some of them were devoid of sculpture on most of their valves, while others (canadensis, Billings, the Silurian dohemica, Barrande, and the present one) were adorned at least with a sculpture of fine strive. Differentiation into dorsal and lateral areas was scarcely marked, and a well-developed carina was probably present. In conclusion, the author wishes to express to Dr. F. A. Bather, F.R.S., and Mr. F. R. Cowper Reed his acknowledgment of their valuable assistance. Helminthochiton equivoca, n.sp. Valves minute, strongly carinate in the median line, (posteriorly) markedly emarginate, lacking insertional lamine, subquadrate. Sculptured with two or three diagonal grooves, and with numerous fine concentric striz running parallel to the free edges. Lower Ordo- vician, D,y (= Arenigian), of Bohemia. Holotype in the Geological Department of the British,Museum (G 22212), from Malé Prilepy. Paratype (G 22213) from Sarka. PAPERS REFERRED TO. J. BARRANDE, Syst. Silur. de la Bohéme, vol. iii, p. 175, 1867. E. Binuines, Paleozoic Fossils of Canada, Ottawa, 1865, p. 394. A. T. DE ROCHEBRUNE, Ann. Sci. Géol., vol. xiv, pp. 1-74, pls. i-iii, 1883. F. R. COWPER REED, GEOL. MAG., 1907, pp. 108-15. J. W. SALTER, in Griffith & M’Coy, Silurian Fossils of Ireland, Addenda, 1846, p. 71. — Quart. Journ. Geol. Soc., vol. iii, pp. 48-52, 1847. H. WOODWARD, GEOL. MAG., 1885, pp. 352-8. G. W. Tyrrell—Petrology of Arran. 305 , V1I.—Tur Perrotocy or ARRAN. By G. W. TYRRELL, A.R.C.Sc., F.G.S., Assistant to the Professor of Geology, University of Glasgow. 1. Tur RIeBECKITE-ORTHOPHYRE OF THE Hoty Istz.—Four occur- rences of acid and sub-acid igneous rocks containing the rare soda-amphibole riebeckite have been recognized in Great Britain, of which that of Ailsa Craig is the best known. The occurrences of Ailsa Craig! and Mynydd Mawr, Carnarvonshire,” are riebeckite- microgranites or paisanites. They contain ragged moss-like areas of riebeckite, together with microphenocrysts of quartz and alkali- felspar, in a microcrystalline groundmass of quartz and felspar. Riebeckite was also found by Dr. Teall in the granophyre of Meall Dearg and the neighbouring area of Druim an Hidhne, Skye.’ Harker described the riebeckite in these rocks as occurring in two forms, one having the usual ragged, sponge-like appearance, and the other being idiomorphic, the faces in the prism zone being well-defined, but with irregular terminations.’ The fourth occurrence differs somewhat from the others. This rock occurs as an intrusion into the Upper Old Red Sandstone, or Calciferous Sandstone of Kaster Eildon Hill, Melrose, and was described by Barron as riebeckite-trachyte or phonolite.* It consists principally of sanidine, occurring both as microphenocrysts and in the groundmass, with interstitial patches of riebeckite, and a little nepheline. Harker describes the rock as an orthophyre.*® It is interesting to be able to add a fifth occurrence of a riebeckite rock in the so-called felsite of the Holy Isle, near Lamlash, Arran. It is noteworthy that Ailsa Craig is only 18 miles from this locality. The Holy Isle forms a steep and - rugged conical hill rising to a height of 1,080 feet, and fitting, so to speak, at a distance es 13 miles, into the recess of Lamlash Bay. It is a prominent landmark in the Firth of Clyde, as prominent almost as Ailsa Craig itself, and moreover of much the same shape. The island is extended in a N.N.W. to S.S.E. direction for 2 miles, and has an average width of half a mile. According to the Survey memoir and map of this district the Holy Isle consists of thick sills of felsite intruded into the third group (red sandstones and conglomerates) of the Lower Trias.’ The latter occupies a narrow strip on the western and southern sides of the island, and is also intruded by a dolerite mass which forms a continuation of the Kuingscross sill and by basalt dykes. The felsites, however, are probably later than the dolerites and basalts. According to the memoir they belong to the group of felsite sills, which seldom show free quartz and are usually non-porphyritic. These are believed to be later than 1 Teall, Min. Mag., ix, 219-21, 1891. 2 Harker, Bala Volc. Ser. Carnarvon, 1889, pp. 50-2. 3 Q.J.G.S., 1, 219, 1894. 4 Tertiary Igneous Rocks of Skye (Mem. Geol. Surv.), 1904, p. 158. > GEOL. MAG., 1896, p. 376. 2 » Petrology for Students, 4th ed., 1908, p- 129; see fig. 33B, p. 128. " The Geology of North Arran, South Bute, and the Cumbraes (Mem. Geol. Surv.), 1903, p. 70. * DECADE V.—VOL. X.—NO. VII. 20 306 G. W. Tyrrell—Petrology of Arran. the contrasted group of quartz-porphyries, since they intrude the latter and are seldom pierced, as the quartz-porphyries are, by the ordinary basalt dykes.’ In several places the ‘felsite’ of the Holy Isle forms great vertical cliffs showing a rude columnar jointing. On the western side of the island the igneous rock clearly rests on horizontal red sandstones and has a sill-like appearance. The rock composing most of the island is a compact, hard, greyish, ‘felsitic’ material, which weathers deeply with a yellowish erust. On breaking open one of the large, loose, angular blocks which strew the slopes, a very regular concentric distribution of colour, due to gradations of alteration, is seen. The exterior yellow zone of decomposed material is often an inch thick, and, with regular gradations. of colour, passes into fresher and fresher rock, and ultimately into a kernel of quite fresh rock. The latter is very compact, dark grey in colour, and shows minute, flashing cleavage- plates of sanidine. The rock frequently breaks into angular tabular fragments conditioned by a close horizontal jointing, and on steep slopes illustrates the formation of screes on a small scale to perfection. Microscopically the rock consists of microporphyritic sanidine in a groundmass of smaller lathy crystals of the same mineral, with riebeckite and minute specks of iron-ore. The sanidine occurs in euhedral, rectangular, simply-twinned crystals, which are evenly and numerously scattered all over the field. The groundmass consists of subhedral laths of sanidine, closely packed together, with abundant riebeckite. The latter appears to occur in two forms, as in the Beinn Dearg granophyre. One set is in small independent prisms, parallel-sided in- the prism zone, but with ragged irregular terminations; the other occurs in the well-known ophitic, mossy, or sponge-like masses. The latter are generally altered to an indeterminate yellow mineral, but the prismatic crystals are quite fresh and show the usual pleochroism from indigo-blue, through greenish-blue, to yellowish-green. Search was made for nepheline, but microscopic and staining methods failed to reveal any trace of this mineral. The small laths of the groundmass show some approach to flow- orientation, but the numerous, short, stumpy, rectangular prisms of sanidine, dispersed in all directions throughout the rock, determine the texture as orthophyric. This, together with the intrusive mode of occurrence, renders the term riebeckite-orthophyre more appropriate than riebeckite-trachyte. The rock differs from that of Ailsa Craig in being entirely devoid of quartz, which occurs both in the. groundmass and as micro- phenocrysts in the latter rock. It is curious that these two islands, so similar in general appearance, should both be composed of riebeckite-bearing rock. If it were possible to examine the contacts of the Ailsa Craig mass, it is not improbable that it would be found to have geological relations similar to those of the riebeckite- orthophyre of the Holy Isle. The closest petrological affinities of the Holy Isle rock, however, are with the riebeckite-phonolite or 1 Geology of North Arran, etc., p. 91. G. W. Tyrrell—Petrology of Arran. 307 orthophyre of the Eildon Hills, Melrose. The latter differs only in its somewhat coarser grain, and in the abundance and large size of its areas of riebeckite. , 2. Crinanires or Waitrne Bay anp Dipprin.—The crinanites are ophitic olivine-analcite-dolerites occurring as dykes in many parts of Argyllshire and the Western Isles. They are so called from Loch Crinan, which lies almost in the centre of their area of distribution. They are closely associated with olivine-dolerites which differ from them only in the absence of analcite, and also with the remarkable monchiquites and camptonites which have recently been described from Colonsay and Mull. Complete descriptions of this suite of dykes have been given by Dr. J. 8. Flett in recent Survey memoirs, and chemical analyses have been made in the Survey laboratory.* These dykes have the north-west trend so common in the Tertiary suite of the Western Isles and the adjacent mainland. Their unusual petrological character, however, has rendered their connexion with Tertiary igneous activity of some dubiety. In the south of Mull a few undoubted Tertiary dykes of analcite-dolerite have been found, and Mr. Wright has found analcite-dolerites amongst the north-west dykes of the Beinn Dearg group in Skye.* The crinanites show transitions to the camptonites in their type- locality, and also have many resemblances to the Carboniferous teschenites which are common in the Midland Valley of Scotland. Dr. Flett, however, enumerates four differences: they are finer in grain than the teschenites, have a perfect ophitic texture, hornblende and biotite are scarce, and they occur as thin, vertical, parallel dykes instead of sills One might add that in general they are much richer in olivine than the teschenites, but poorer in analcite and alkali-felspars. These mineralogical differences are clearly brought out in a comparison of the chemical analyses of the two rocks. The teschenites are much richer in ‘alkalies and combined water, but considerably poorer in ferrous iron and magnesia.° The present paper records the occurrence of a dyke of crinanite at Whiting Bay in the south-east of Arran, and also records that the great sill of Dippin, hitherto regarded as a teschenite, is much closer in its affinities to crinanite. The sills of Kingscross and of the Clauchland Hills are also to be regarded as crinanites. All these rocks intrude the Triassic sediments, and are most probably of Tertiary age. The Arran occurrences thus furnish one more link in the chain of evidence which connects the crinanites and the associated monchiquites and camptonites of the type-locality of Argyllshire with Tertiary igneous activity. 1 Summ. Prog. Geol. Surv. for 1909, 1910, p. 52. 2 The Geology of Knapdale, Jura, and North Kintyre, 1911, pp. 116-18; The Geology of Colonsay and Oronsay, with Part of the Ross of Mull (Mem. Geol. Sury.), 1911, pp: 41-6. 3 The Geology of Colonsay and Oronsay, 1911, p. 41. 4 The Geology of Knapdale, Jura, and North Kintyre, 1911, p. 117. ° For analyses of teschenites see The Geology of the Neighbourhood of. Edinburgh (Mem. Geol. Sury.), 1910, p. 299. 308 G. W. Tyrrell—Petrology of Arran. Petrography.—On the shore of Whiting Bay and at Kingscross Point are numerous rounded pebbles and boulders of a fresh doleritic rock which is rendered prominent by a distinct spotting of rounded lighter areas on a darker ground. Ultimately this rock was traced to a thick dyke penetrating the Triassic sandstones on the shore of Whiting Bay, a little to the north of the School. In thin section the rock is seen to consist of an ophitic plexus of plagioclase and augite, in which the former is largely predominant. Fresh olivine is very abundant, and a skeletal or platy ilmenite only less so. Analcite or a fibrous radiating zeolite fills many of the polygonal interspaces between the felspar laths. The plagioclase is euhedral and zonal, the composition ranging from acid labradorite (Ab, An,) in the interior to oligoclase (Ab, An,) in a thin marginal zone. As usual, the undulose “extinction due to zoning is very prominent in untwinned sections cut parallel to the clinopinacoid. The augite is a deeply-coloured purplish variety, with a pleochroism ranging | from deep purplish-brown to a pale sepia, and is probably rich in titanium oxide and alkalies. It is very subordinate in quantity to the plagioclase, and is cut up by the latter into thin strips and small triangular or polygonal patches. The abundant olivine is very fresh, or at most has suffered only incipient serpentinization, and occurs in small, more or less rounded, subhedral granules, which are frequently enclosed along with ilmenite in the plates of augite. Turbid but still isotropic analcite fills up many of the straight-sided interspaces between the felspars. In some cases, however, the spaces are filled with a low-polarizing, radial zeolite, whose optical characters agree with those of scolecite. ‘The ilmenite is mostly skeletal, but sometimes occurs in long thin plates or rods, which are enclosed in and earlier than the titanaugite, but frequently mould the terminations of felspar laths. Occasionally small scraps of red biotite are associated with the iron-ore. The spotting visible in the hand specimen is due to a comparative scarcity of the ferromagnesian minerals in certain areas, and is only recognizable with difficulty in thin section. From this description it will be evident that this rock is identical with crinanite. I have been able to confirm the identification by comparison with slides of typical erinanite from Argyllshire kindly lent by the Geological Survey. The great sill of Dippin which has been described by Corstorphine as olivine-analcime-diabase,’ and by Harker as teschenite,? appears to me to be more nearly related to crinanite. It agrees with the latter in the perfect ophitic relations between augite and plagioclase, and in the abundance of fresh olivine, both of which characters are very unusual in the teschenites. In many specimens (e.g. from the north end of the Dippin cliff) the interstitial analcite is not at all prominent. Only in some outcrops in Glen Ashdale does the analcite become as abundant as in the teschenites. The mass of the Dippin rock, however, is much coarser in grain than is usual with the typical crinanites, but this, of course, is conditioned by its mode of occurrence ' Tscherm. Min. Petr. Mitth., xiv, 463-5, 1895. * The Geology of North Arran, South Bute, and the Cumbraes (Mem. Geol. Surv.), 1903, pp. 112-14. Reviews—The Geology of the Lizard. 309 in thick sills. Near the contacts the Dippin rock becomes identical with crinanite even in the matter of grain-size. The sill of Kingscross Point must also be correlated with the Dippin sill and with the crinanites. It differs from the Dippin rock in carrying a much smaller quantity of interstitial analcite and zeolites and in a finer grain-size. The felspars are approximately equal to the titanaugites in bulk, but the individual crystals are much smaller. The ophitic plates of titanaugite are pseudo-porphyritic in a groundmass composed of closely packed laths of plagioclase. The Kingscross sill has suffered a curious veining by a tachylytic basalt, and has also developed pegmatitic variation-facies in which analcite and other zeolites are very prominent. From Allport’s description it is probable that the great sill which caps the Clauchland Hills is also a crinanite. He says: ‘A typical specimen from Dun Fion contains crystals of plagioclase beautifully striated, augite and olivine in a remarkably fresh condition, magnetite, a few plates of brown mica, a little apatite, and a clear amorphous glass in the interstices of the constituents.” 1 The ‘‘ clear amorphous glass”’ is almost certainly analcite. All the rocks described above are unquestionably Tertiary in age. Very similar rocks, however, are to be found amongst the alkalic Late Carboniferous or Permian eruptives of Ayrshire.” Most of the rocks of this sub-province which are to be regarded as related to crinanite are intrusive in the Permian sandstones and underlying lavas of the Mauchline basin, and are’ associated with analcite-syenite. A good crinanite from an intrusion at New Gilston, Fifeshire, has recently been brought to my notice by Miss A. ‘I’. Neilson, of the Hunterian Museum, University of Glasgow. ; REVIEWS. I.—GeronoeicaL SurveEY Memoir. Tur Grotocy or THE Lizarp anp Menzace. By Dr. J. S. Frert, M.A., and J. B. Hitt, R.N. 8vo; pp. viii, 280, with 15 plates and 10 text-illustrations. London: printed for His Majesty’s Stationery Office, 1912. Price 5s. Ke ENEAGE, as we are told in the preface to this memoir, is an old Cornish name for the Lizard promontory, south of the Helford River; so that the name applies to the whole of the Lizard area, but strictly speaking not to the northern margin in the Geological Survey map, which includes Rosemullion Head on the east and Breage on the west. The colour-printed map (Sheet 359) shows clearly the line of demarcation between the igneous and metamorphic Lizard Series and the mainly sedimentary series, which in old days was known generally as ‘killas’. This forms the northern portion of the area, together with some intrusive and interbedded igneous rocks, including a fringe of granite at Constantine and a small tract at Breage. The two great rock-series appear to be 1 Q.J.G.S. xxx, 563, 1874. . 2 Tyrrell, GEOL. Maa. (V), IX, 124, 1912. 310 Reviews—The Geology of the Lizard. separated by a fault or thrust-plane, heading to the south and south-east, and carrying well-marked breccia. The disturbance is well shown near Polurrian Cove on the west and near Porthallow Cove on the east, but it cannot be definitely traced throughout the intermediate ground. The southern area has been mapped and described by Dr. Flett, the northern by Mr. Hill. The entire region is a somewhat irregular plateau, averaging about 280 feet in elevation, but rising on the serpentine of Goonhilly Down to 370 feet, and on the hornblende schist of Roskruge Beacon, west of Porthallow, to 378 feet. This plateau, eroded to a great extent probably in Miocene and early Pliocene epochs, was further planed down in later Pliocene times, when the area was submerged to the extent of about 420 feet. Relics of gravels regarded as of Pliocene age (but not fossiliferous) occur on the gabbro of Crousa Common north of Coverack. The coastline in general is rugged and rocky, and often difficult of access, but characterized by numerous highly picturesque coves, while the broad tidal waters of the Helford River and the Loe valley south of Helston are bordered by wooded slopes of great beauty. The region in general is described as essentially an agricultural and not a mining country, and in this respect it compares with the metamorphic area of Salcombe in South Devon, which is included in the fertile district of the South Hams. In the Lizard the least cultivated portions are on the serpentine, which yields a thin clayey soil, liable to be waterlogged, and the land is comparatively barren and dreary. A full, and in all respects excellent, account of the previous literature relating to the Lizard Series is given by Dr. Flett, and it is interesting to read of the gradual progress of knowledge and of the diverse views concerning the origin and relations of the rocks in this complex area. ‘To the elucidation of the problems Professor Bonney, Dr. Teall, Mr. Howard Fox, Mr. Harford J. Lowe, also the late General McMahon and Alexander Somervyail, have been the principal contributors. It has remained for Dr. Flett to examine in detail the entire area and bring the experience gained by seeing the whole of the evidence to the interpretation of the mineral changes in the rocks, their sequence, and structural features; and it may be affirmed that as complete a story as possible has been unfolded by the masterly way in which this petrographical area has been investigated. The one point on which we fail to find definite expression of opinion is that of the geological age of the Lizard rocks, though it may be inferred that Professor Bonney’s reference of the mica schists to the Archzean is not contested by Dr. Flett, who regards the Old Lizard Head Series as ‘‘an important part of the Lizard schists’’.1 Moreover, the intimate connexion of the series appears manifest when we read that ‘‘in 1893 Somervail advanced the hypothesis that all the principal rocks of the district, the horn- blende schist, serpentine, gabbro, black dykes, and banded gneisses, were differentiated from one magma. As he had already arrived at a correct conception of the sequence of these rocks, he may be regarded 1 See also Flett’s account of ‘‘ The Geology of the Lizard ’’ (Proc. Geol. Assoc., xxiv, p. 118, 1913). Reviews—The Geology of the Lizard. 311 as the first to solve one of the most fundamental, and at the same time most obscure, problems of Lizard geology’’. With regard to the vexed subject of fluxion banding and foliation, it is remarked that ‘‘in the plutonic and intrusive rocks of the Lizard there is a foliation intimately connected with the injection of the igneous magma, but it is clear also that earth-movements were going on at the same time. The most important fact to bear in mind is that the igneous rocks can be shown to have attained their present meta- morphic state as soon as, or very shortly after, they had consolidated”. The following sequence, in descending order, is recognized by Dr. Flett :— Granite and Granite Gneiss. Kennack Gneisses (banded). Dolerite and Epidiorite dykes. Gabbro (with augen gabbro and gabbro schist). Troctolite. Serpentine (Bastite, Tremolite, and Dunite varieties). Hornblende schists: Traboe schists. Treleague Quartzite. Man of War Gneisses. Hornblende schists : Landewednack schists. ( Green schists. Old Lizard Head Series ; Granulites. Mica schists. It is pointed out that sedimentary rocks are represented by the mica schists, granulites, and Treleague quartzite; and that the varieties of serpentine pass one into another, the dunite variety being the marginal facies, the tremolite serpentine adjoining it, and the bastite variety or lherzolite being the central rock. In separate chapters full particulars are given of the subdivisions of the metamorphic rocks of the Lizard Series. Turning now to the northern: series of rocks, we find the sedi- mentary Mylor, Falmouth, and Portscatho Series of Mr. Hill, grouped as Ordovician (?), although as they presumably underlie the Veryan Series regarded as of Llandeilo or Arenig age, and ‘‘ probably Arenig”’, the three former series may include rocks that are pre-Ordovician. Only the Veryan Series has yielded fossils, and with it are grouped the Radiolarian cherts of Mullion Island. Lower Devonian is recognized in the Manaccan Beds, which consist of slate, sandstone, and conglomerate, with fragments derived from the Portscatho and Veryan rocks. The sequence maintained by Mr. Hill has, however, been contested by Mr. Upfield Green and Mr. C. D. Sherborn, who, in their latest grouping, place the ‘ Dartmouth, Falmouth, Ladock, Grampound, Manaccan, Mylor, Portscatho, and Veryan”’ Beds in the Lower Devonian (Gedinnian); and they apply the term Veryan to ‘beds containing lenticular inclusions yielding Ludlow, Wenlock, and Woolhope fossils”, placing them beneath the Manaccan Beds and above the Ordovician quartzites of Gorran.' There does not appear to be any justification for this application of the term Veryan, as it strictly belongs to the strata (thin limestones, Radiolarian cherts, slates, quartzites, and pillow-lavas) grouped by Mr. Hill as Ordovician. 1 See GEon. Maa. for 1912, p. 560. 312 Reviews—C. D. Walcott?s Cambrian Brachiopoda. The important discoveries of Silurian (Ludlow) fossils made by Mr. Green and Mr. Sherborn in ‘ Black slates with limestone lenticles”’ at Fletching’s Cove near Porthalla (Porthallow on map), and in the ‘‘Slates with inclusions” at Nare Cove, south of Nare Head, do not prove that the inclusions and lenticles are of a con- glomeratic character and of Devonian age. In such a region of faulting and thrusting and probable infolding, it would seem more likely that the inclusions have been brought about by disturbance. The fact observed by Mr. Hill that the Manaccan conglomerate contains fragments of the Portscatho rocks, etc., does not appear to have been taken into consideration by Mr. Green and Mr. Sherborn, and this evidence strongly favours Mr. Hill’s view that the Manaccan conglomerate forms the local base of the Devonian. It is to be hoped that these three geologists may be able in due course to harmonize their views. Materials for the definite determination of some of the problems are still wanting. It has been pointed out that the absence of any fragments of the Lizard Series in the Ordovician and Devonian rocks of the area is remarkable, and cannot be satis- factorily explained; and there are features that have led Mr. Hill to see evidence of a transitional passage from the Veryan group into the Lizard Series. The facts for and against this hypothesis are fully discussed in the memoir, wherein it is stated ‘‘that this difficult problem is not yet by any means settled”’.! In thus referring to the chief controverted subjects, we have no space in which to enlarge on the accessions to knowledge in reference to the various igneous rocks and to metamorphism. It should be mentioned, however, that apart from the Lizard Series there are pillow-lavas (spilites), granite, elvans, and mica-traps in the northern area, and these are duly described. Some account is given of the possible derivation of the Gunwalloe beach-shingle from an old Eocene deposit, and then follow descriptions of the Pliocene gravels, raised beaches and head, submerged forests, and coast erosion. An interesting and instructive account is given of the soils and agriculture, followed by notes on the water supply, building materials, serpentine industry, and mining, to which last subject Mr. D. A. MacAlister has contributed. The plates include excellent views of scenery, rock-structures, and photomicrographs of rocks, and among them is one of a “ Glacial Boulder on the Beach at Porthleven’”’. This, known as the ‘ Giant’s Rock ’’, is a block, about 50 tons in weight, of ‘‘ microcline gneiss of a type unknown in Britain’’, and has evidently been derived from the raised beach. II.—Primirive Bracuropops. CampBrian Bracutopopa. By Cuartes D. Watcorr. Monographs of the United States Geological Survey, vol. li, part i, pp. 1-872; part ii, pp. 1-363; platesi-civ. 4to. Washington, 1912. HIS immense work is another example of the wonderful energy of American scientific investigators, and is afurther proof of their very comprehensive grasp of their subjects. Not alone the students 1 See also Hill, Proc. Geol. Assoc., xxiv, p. 153, 1913. | Reviews—C. D. Walcott’s Cambrian Brachiopoda. 313 ot Palzozoic rocks, but all paleontologists and all evolutionists owe to the gifted author, Dr. Walcott, their cordial thanks for a monograph dealing so fully with the Brachiopod fauna which existed in those far-off days when the earth was yet in her youth. Looking at these two fine volumes, with their testimony to careful scientific work on every page—these two volumes published by the United States Geological Survey, well printed and magnificently illustrated—one is doubtful whom to envy most, the scientific investigator who has not only the ability and the patience but also the time to execute such a task, or the Government. which so ably places his results before the world. For publication is a very important factor. There is nothing more stimulating to any worker than to know that his task when accomplished will be adequately printed; there is nothing which undermines the worker’s energy more than a doubt whether his work may ever see the light, while the feeling that it may in the end be mutilated or very inadequately presented on the score of expense is almost as fatal. Scientific workers in other countries, then, might be forgiven if they exclaim to Dr. Walcott, or to his Government, « Almost thou persuadest us to become Americans! ” What, however, of the contents of these volumes? To criticize them in detail would be futile. Dr. Walcott has made a life study of the faunas of the Cambrian rocks, and his expert knowledge is of worldwide reputation, proved and attested by many previous com- munications. The present monograph on the Cambrian Brachiopods of the world has occupied the author for the last ten years: that it has been accomplished in that space of time is a tribute to the author’s untiring perseverance. “This monograph includes the description of 44 genera, 15 sub- genera, 477 species, and 59 varieties of Cambrian Brachiopoda, and of 3 genera, 1 subgenus, 42 species, and 1 variety of Ordovician Brachiopoda. . . . In this paper the Brachiopoda are treated in three ways— historically, geologically, and zoologically. Historically the treatment comprises (1) a bibliography and (2) a table of synonymic reference. . . . Geologically the distribution of the Brachiopoda is considered under the following headings: (1) General geographic and stratigraphic distribution; (2) detailed geographic distribution; (8) detailed stratigraphic distribution; (4) habitat ; and (5) fossil localities. Zoologically the discussion covers (1) the physical characters of the Brachiopoda; (2) their distribution ; (3) their evolution; and (4) their classification. Lastly come the detailed descriptions of genera and species and the illustrative plates” (p. 11). The number of species of Cambrian Brachiopoda is remarkable ; it is an interesting picture of how much development and differ entia- tion had been accomplished even in those early days. Tables of Detailed Geographic Distribution are given in pp. 114 et seqq., but one misses a comparative analytical table of numbers of species in different regions. North America supplies by far the largest number —the species are some hundreds; but as a remarkable contrast South America is credited with only five species. Next to North America 314 Reviews—C. D. Walcott’s Cambrian Brachiopoda. in point of numbers comes Europe with about a hundred species, but the British Islands can only boast about one-fifth of this total; the greatest number is provided by Scandinavia, including Finland. Asia yields about forty species and Australia six, but there can be little doubt that further exploration of these regions would increase the number. This very elaborate monograph cannot fail to be of the utmost importance to the student of the Brachiopoda of the Paleozoic rocks. There is a bibliography extending to thirteen pages, and, what is always of the very greatest assistance to the worker, there is an exhaustive Table of Synonymic References—how exhaustive may be judged from the fact that it extends to about seventy pages; it is also testimony to the large amount of investigation, and the constant rearrangement in the light of further knowledge, which the Cambrian Brachiopods have received. That the present monograph exhibits the nomenclature in anything like a final form no one could pretend to hope, especially when it is considered how very obscure are some of these small fossils, and how difficult they are to interpret. But the energy which Dr. Walcott has brought to bear on the elucidation of his subject deserves our warmest thanks. America may well boast of the industrious, and, what is perhaps more important, of the very progressive investigators of Brachiopoda which she has produced, men who have given us what has almost seemed to be revolutionary work. James Hall and C. E. Beecher, Professor J. M. Clarke, Professor Schuchert, Dr. E. R. Cumings, and others form with the writer of the present monograph a band who have made our knowledge of fossil Brachiopoda, especially of the older formations, advance from comparative chaos to well-arranged order. Considering the nature of the remains and the magnification so frequently required, the excellent plates are deserving of special commendation. Dr. Walcottsays (p. 13): ‘‘the drawings have been prepared mainly by Miss Frances Wieser, of the United States Geological Survey. The plates are the evidence of her faithful work.” They are; it is not only good work but a magnificent task. There are over a hundred plates, and the number of separate figures must run into several thousands, figures full of fine detail, all very carefully executed. Nothing more beautiful has been placed before the student of Cambrian Brachiopoda: perhaps if we said of any Brachiopoda it would not be incorrect. There is a small matter connected with the plates—mainly an editorial matter—to which we would call attention. It is very desirable that all the explanation of each plate should appear in the one opening, opposite the plate. In view of the immense amount of literature, workers’ time should be saved in every way, and reference to figures of a plate should be made as clear and easy as possible. But this cannot be where there is the too common fault of separating the explanation from its plate, or even, as in the work before us, carrying the explanation over to a leaf behind the plate. In many cases in the present work such carrying over has been quite needless, and all the explanation could have been placed on the facing page. In other cases the use of smaller type would have enabled the Reviews—Fourtaw’s Egyptian Hchinoids. 315 required position to be achieved. In yet other cases where even that expedient would have failed, askeleton explanation printed at the top of the facing page, to be followed by the detailed explanation, would have been of great assistance. Anything which lessens chances of misquotation and facilitates reference to a work makes that work, in our opinion, the more valuable. And frequent reference to such a work as this is to be desired, for the monograph thoroughly deserves it. We congratulate Dr. Walcott on the completion of a magnificent task, most worthily executed. It is another monument to his great abilities. IlJ.—CaraLocuE Drs INVERTEBRES FOSSILES DE LEG¢ypre REPRESENTES DANS LES CoLLEections pu Gxonocican Musrum av Carre. Par R. Fourtav. Terrains tertiaires. 1ére partie: Hchinides Kocénes. 4to; pp. 1-98, pls. i-vi. Le Caire. Gouvernement égyptien. Administration des Arpentages. 1913. URING the Cretaceous and Eocene periods the Echinoid fauna of the Mediterranean region seems to have been one of the richest known from any part of the world. In the case of the former period the wealth of species and individuals may probably be ascribed to the littoral conditions then prevalent in Northern Africa, where, perhaps in a tropical climate, shore-life must have been uniformly prolific. It might be expected that the relatively pelagic conditions which came in with the Tertiary epoch would have resulted in a reduction in numbers and variety; and, indeed, it may yet be a question whether the list of 130 species recorded from the Egyptian Eocene alone may not in some measure owe its length to excessive zeal in the separation of ‘ species’. This question seems the more appropriate when it is found that the genus Schizaster is credited with eighteen species and Lehinolampas with nineteen ! In the study of the fossil Echinoids of the eastern part of the Mediterranean the mantle of de Loriol has fallen upon M. R. Fourtau, and he proves himself a worthy successor in the task of analysing the, as yet, fragmentary knowledge of the fauna. The present catalogue supplies a valuable résumé of past work on Egyptian Eocene Echinoids, and adds not a few new forms to the list. Although the main work is necessarily purely systematic, the author gives an interesting ‘apologia’ in his Introduction. The methods of systematists often seem to date from the earlier half of last century, when, in the absence of any definite creed of evolution, the slightest differences between two specimens must needs lead to their specific separation. Although M. Fourtau adopts these methods in no small degree, he gives at the outset a confession of faith in the principles of the ‘‘ Enchainements du monde animal”’. He anticipates that, with fuller knowledge, it will be possible to unite many of the ‘species’ described in his catalogue into genetic series, but he regards all such attempts at present as being premature. He differentiates very properly between the zoological and stratigraphical conceptions of species, and reluctantly restricts his paleeontology to its geological aspect. 316 Reviews—Dr. Ethel de Fraine on Sutclifiia. For the purposes of a catalogue such a course is inevitable. But M. Fourtau suggests that in no other place would any but systematic work upon Egyptian fossil Echinoids be appropriate or even feasible. Surely 130 species from one formation represent sufficient material for philosophical consideration! Any phylogenetic grouping, however tentative and even inaccurate, would be more illuminating than a purely alphabetical arrangement of species. May we express the hope that M. Fourtau, with his unique opportunities and peculiar knowledge, will at some future time yield to his temptation to discuss rather than describe his specimens. In the catalogue under consideration there seem to be more than the average number of misprints and other small inaccuracies. Misprints in dates are always dangerous, and on p. 88, under the heading of Zchinolampas ovalis, there occurs a flagrant case. Would it not be a safeguard if new species were indicated as such in words, and not merely ascribed to the author with a date? In the present work new forms appear, ascribed to R. Fourtau under the varying dates of 1912, 1913, and even 1914! In one case ( Conoclypeus delanouet, var. macropyga) the legend to the plate includes the words ‘nov. var.’, whereas in the text it is found that the variety was described in 1908! Surely the removal of such fruitful sources of confusion to later systematists is worth a little care in the proof- reading. A discrepancy in the title of the work, as engraved on the plates and as printed on the cover, is a further illustration of the unnecessary trouble that may be caused to future bibliographers. In spite of the above criticisms of detail, the catalogue as a whole must be regarded as an invaluable contribution to our knowledge of Eocene Echinoids, and its publication would, of itself alone, assure M. Fourtau a high place among systematic Echinologists. Dei Gs 18L. TV.—Srrvucrure anp AFFINITIES OF SUTCLIFFIA. PAPER in the Annals of Botany, by Dr. Ethel de Fraine, concerns a fragment of a petrified stem which was obtained from the colliery at Dearnley, near Littleborough. The specimen is of Lower Coal- measure age, and obtained from a nodule in the roof of the workings, probably from the same seam as the stem of Suteliffia insignis, described by Dr. Scott (Trans. Linn. Soc. London, ser. 11, vol. vil, pt. iv). The specimen was of large size, 9°5 by 3°5cem. being the maximum transverse dimensions, while the total length of the fragment was about 25 em. The structure presents considerable complexity, and consequently a model of the vascular tissues was constructed, in order to elucidate the behaviour of the strands. The main vascular axis consists of a solid central strand of wood (aprotostele), surrounded by leaf-traces of varying size (the ‘meristeles’); a network of extra-fascicular bands of wood and bast encloses the stele and ‘ meresteles’, while a zone of secondary cortex forms the limit of the specimen. The leaf- traces (‘ meristeles’) pass out from the protostele without appreciable disturbance of its tissues, and are precisely similar to it; they divide up irregularly into smaller bundles, and are ultimately entirely used up 1 Vol. xxvi, No. civ. { . Reviews—F. Frech’s Catalogue of Fossils. 317 in the production of the small concentric foliar traces. Occasionally © accessory concentric bundles are present, recalling the similar strands which occur in the cortex of Cycas. The vascular strands of all orders, except the ultimate foliar traces, are surrounded by a broad zone of secondary wood. On account of the general structure of the vascular system, the origin and behaviour of the ‘meristeles’, the leaf-trace bundles, and the close agreement in histological details (such, for example, as the pitting on the tracheidal walls), the stem is included in the genus Sutclifiia of the family Medulloseze. It is provisionally attributed to Sutcliffia insignis, Scott, for the additional features which are characteristic of the specimen are such as would be expected to occur in an older stem: such features are the occurrence of secondary wood, the extra-fascicular strands, the secondary cortex, and the absence of leaf-bases. The specimen is of some importance on account of the additional light which it throws on the affinities of the extinct family of the Medullosee. The great possibility of the origin of this group from a fern-like ancestry has been fully considered elsewhere, and many investigators have regarded it as the source of origin of the Cycadacee. — The discovery of the present stem adds considerable weight to this view, for in many respects the structure is of a distinctly Cycadean type. It is suggested that by modification of the protostele and elaboration of the extra-fascicular zones of some such genus as Sutclifia, the Cycadaceee were evolved; while, on the other hand, increasing complexity in the number and arrangement of the steles may possibly have led through such a type as the Englsh Medullosa anglica to the complex Permian Medulloses. V.—Fossitrum Caratocus. I. Animalia. Editus a F. Freca. Pars 1: F. Frech, Ammonez Devonice (Clymeniide, Aphyllitide, Gephyroceratide, Cheiloceratide). 4to; pp. 42. Berlin: Junk, 1913. Price 4 marks. HIS seems to be just one of those works whose usefulness fails because the compiler refuses to adhere to a strictly alphabetical arrangement. So splendid an example of what an Index Palzonto- logicus should be was bequeathed to science by H. G. Bronn that it is difficult to comprehend the mind of those who spend their time on a systematic arrangement which in nearly every case can only be of service to the narrow specialist, and little indeed to him, for he already knows his subject. Further, why limit the references to Devonian forms? ‘There is already much grumbling among those who have to consult the three or four indexes extant for generic names and a request that they may all be thrown into one, but in this proposed work we are threatened with a separate index ~ not merely to each group but to each geological horizon of the families of the group. In the work itself we consider that a date should be attached to each entry. We note the twenty-nine titles quoted do not represent the complete literature; we do not understand on what authority the name Agoniatites, Meek, is rejected for Aphyliites, Mojs.; and we hope ‘‘ Mopisovus”’ on p. 25 will be intelligible to the uninitiated. 318 Reviews—Dr. J. H. Poynting—The Earth. If our German friends would organize a staff and get another ‘Bronn’ ready for the next generation they would be doing a real service to Paleontology, but we honestly think that work published in parts in this way is of little or no service to the real worker, especially when it is arranged in systematic and not alphabetical order. It is never wise to introduce into a reference book any personal idiosyncrasies. ViI.—Tue Earra: irs Suapn, Size, Weitent, anp Spry. By J. H. Poyntine, Se.D., F.R.S. 8vo; pp. 141, with 49 text-figures. Cambridge: at the University Press, 1918. Price 1s. net. IFFERENT branches of geology have been dealt with in previous volumes of this enterprising series, and Professor Poynting’s little book is concerned with the earth from a physical aspect. There are only three chapters, and their simple-sounding titles are: ‘‘ The Shape and Size of the Earth,” ‘‘ Weighing the Earth,” and ‘‘ The Earth as a Clock.’”’ In telling the story of the growth of the idea of a round earth, the author would take us to the top of a hill on aclear day to look over a stretch of lowlands, where we might with the ancients conclude there was nothing to suggest that the earth is not flat. In our first chapter we are told how a different conception of the earth’s form came into being, and how Columbus proposed to reach India by sailing to the west. A few simple figures and some easy calculations are given in support of the modern view, and these are followed by a description of the method of measuring distances on the earth’s surface. The base-line method of measuring is illustrated also by an account of the finding of the distance of the nearer stars. In beginning his second chapter the author illustrates clearly the relationship between the weight and mass of the earth. We then read of the earth-weighing experiments—the early ones of Newton, Bouguer, Maskelyne, and Cavendish, and the later and more delicate one of Professor Boys. When considered as a clock, our planet is regarded, of course, as whirling round the sun, and we see how the spin of the cyclones is connected with this movement. The principle of Foucault’s pendulum is also dealt with. But by far the most interesting topic is that of the tides, which are treated in connexion with Sir George Darwin’s discoveries. It is shown that the tides are gradually reducing the earth’s spin, that the action of the moon on them is gradually lengthening the day, and the reaction of them on the moon is lengthening the month. The same reckoning points to the probability of the moon and the earth forming the same body in the past, and the likelihood of the moon’s ending her journey by reunion with the parent globe in the far-distant future. VII.—Errects or PressurE AND TEMPERATURE ON RocK-FORMATION. EOLOGICAL speculations on matters connected with the formation of rocks have often been founded on misunderstood or mis- interpreted experiments. Mr. John Johnston and Mr. L. H. Adams, in a paper on the effect of high pressures on the physical and chemical behaviour of solids, published in the number of the American Journal Reviews—Prof. H. W. Skeats—Nepheline at Omeo. 819 of Science for March, 1913, have done good service by collecting and critically discussing the available data. They point out that a non- uniform pressure, i.e. one involving a shear, is an incomparably more effective agency than a uniform pressure, which is not so important as a high temperature. VIII.—On tHe occurrence or NepHELINE IN Puonowre Dyxzs ar Omezo. By Professor K. W. Sxeats. Section C: pp. 126-381, with one plate. Australasian Association for the Advancement of Science, 1912. HIS paper gives a list of previous records of felspathoids in Victoria, and shows that most of these have been due to incorrect determinations. ‘he author corrects his previous record of nosean and melilite in the alkali rocks of Mt. Macedon. A brief sketch of the geology of Omeo, Kastern Gippsland, is given. Granites and quartz-diorites are intrusive into pre-Ordovician or pre-Cambrian schists, and there is a group of anorthoclase-trachytes and solvsbergites, which are younger than the plutonic rocks. Another group of dykes occurs at Omeo, and the phonolite dykes here described are the youngest in this area. The rocks are described in detail, and the percentages of alkalies in one rock have been determined. The mineral composition is : soda-orthoclase 46, nepheline 28, and egirine 25 per cent. A mineral occurring interstitially between the felspars is referred provisionally. to cancrinite. ITX.—Cawnapa. GroLocicaL SURVEY oF CANADA. (A) In Memoir No. 17z (1912) is an account of the ‘‘ Geology and Economic Resources of the Larder Lake District, Ont.”’, by Mr. M. E. Wilson. The formations shown on the map are Keewatin (greenstone and various schists, slate, dolomite, quartz- porphyry, and rhyolite), Pontiac schist, Laurentian (granite, gneiss, etc.), Huronian (conglomerate and greywacke), Post Lower Huronian (diabase, etc.), and Pleistocene and Recent deposits. The mineral products include gold, silver-lead, copper, cobalt, nickel, molybdenite, and iron. ‘The report contains interesting views of scenery and rock-structures. (B) Memoir No. 35 (1912) gives the results of a ‘‘ Reconnaissance along the National Transcontinental Railway in Southern Quebec ”’, by Mr. J. A. Dresser. The rocks described include Cambrian, Ordovician, Devonian (igneous), and Drift. The district has been glaciated from the N.N.W., and the rock surface is generally, and in places heavily, covered by soil. Stratified Drift deposits of clay, sand, and loam occur in the lowlands and in some of the upland valleys. The mineral prospects are not of great promise. Small quantities of asbestos, chromite, chalcopyrite, and bog iron-ore occur; there is slate of good quality, also quartzite, and peat-bogs. Much of the district is suitable for farming, and part for lumbering. Among the illustrations there is a striking view of the St. Lawrence lowland. 320 Reviews—Geology of Canada. (C) Deparrment oF Mines, Canapa: Murnus, Brancu, 1912. Pyrires in CAnapA. By A. W. G. Witson. pp. xi+ 202, with 27 plates, 26 tables, 29 figures in the text, and 1 map. This report, while outlining the pyrites resources of Canada, has for its object the promotion of a further development of these resources. If is pointed out that, if a steady supply of a uniform grade of ore were assured, more than four times the present production in Canada of this ore would find a ready market. This market might be still further increased on account of the rapid expansion of the sulphide pulp industry in Canada. The book gives a short account of the chemical and physical properties of the chief sulphur ores, and notes on the mining and marketing of pyrites. The statistics of the production of pyrites are given in fifteen tables. The occurrence of pyrites in Canada is treated at length, some forty prospects being described. This chapter is illustrated by an admirable series of photographs and by a map showing the positions of the pyrites deposits in Eastern Canada. The same chapter contains descriptions of the pyrrhotite at Sudbury, Ontario, and of the famous pyrites deposits of Huelva, Spain, and of Norway and Japan. The remaining chapters deal with the roasting of pyrites, the manufacture of sulphuric acid, and the importance of pyrites to the paper-manufacturing industry. Appendices give a list of firms interested in Canadian pyrites, types of furnaces used for burning sulphur, a discussion of the use of pyrrhotite as a sulphur ore, and of the contact process for the manufacture of sulphuric acid. The book is most profusely illustrated. It contains a fund of information of a highly practical nature which must prove invaluable to those actively engaged in the production of pyrites, while its less technical matter cannot but appeal to those interested in the scientific aspects of pyrites deposits. (D) Mrynerat Propvcrion, Canapa, 1911-12. (1) A general summary of the mineral production of Canada during 1911. (2) Preliminary report on the mineral production of Canada during 1912. By J. McLetsux. The decrease in mineral production of 1911, as compared with 1910, is attributed largely to the strike of coal-miners in Alberta and in the Crowsnest district of British Columbia. The preliminary report for 1912 shows an increased production for every important mineral mined with the exception of petroleum. The working of the nickel-copper ores of the Sudbury district of Ontario in 1912 shows a greatly increased output. Small shipments of nickel ore were also made in 1912 from the Alexo Mine at Kelso in the Nipissing district. (E) Guonoeicat Survey, Brirish CoLtumBra. Map 62a (to accompany Memoir 34). Nelson and vicinity, West Kootenay, British Columbia. A geological and topographical map of an area of about 120 square miles, on the scale of 1 mile to the inch, with contours at intervals € Reviews— United States Geological Survey. 321 of 250 feet. It is based on the map published in 1904, and gives the relations of the Nelson batholith (granites, monzonites, and quartz- diorites) and its accompanying dykes to the rocks of the Rossland and Pend d’Oreille groups (? Carboniferous). X.—Proressor Dortrer’s Mrineraboey. HE first part of a second volume of Professor Doelter’s great work (Handbuch der Mineralchemie, edited by Hotrat Professor , Dr. C. Doelter; vol. 11, pt. i, pp. 160; Dresden and Leipzig, Theodor Steinkopff, 1912; price 6-50 marks net), which deals with silica and the silicates, comes fully up to its predecessors in point of view of interest and importance. It opens with a resumé by Professor Becke of the physical characters of the silicates. He compares the refraction of many species with the corresponding value calculated from Gladstone and Dale’s well-known law; the agreement is often very close, but discrepancies are met with which eall for further investigation. The general theory of the optical characters of isomorphous mixtures is considered, with special reference to the plagioclase felspars. A lucid and thorough account of the paragenesis of the silica minerals comes from the pen of Professor J. Koenigsberger. Professor Doelter himself writes on the vexed question of the constitution of the silicates, and discusses the various theories that have been put forward. He also describes very fully the physical characters of quartz, chalcedony, and opal, the information given being exhaustive and well up-to-date. XI1.—Unitrep Srares GronogicaL SURVEY. E have received Water-supply Papers Nos. 281, 283, and 301, * dealing with the Surface Water Supply of the United States, including the North Atlantic Coast and Ohio River Basin; also No. 299, part ii, dealing with stream measurements in San Joaquin River Basin, California. Illustrations are given of the apparatus used in gauging the flow of streams. In No. 299 there are views showing the measurements made by the engineers of the Geological Survey by means of a current meter, which is operated from a bridge, a car suspended on a cable, a boat, and by wading. The Thirty-third Annual Report of the Director (Mr. George Otis Smith) for the year ended June 30, 1912, contains a useful map showing areas of the United States covered by geologic surveys. There are some interesting remarks on the work of the Committee on Geological Names, their duty being to consider all geologic names of formations suggested by members of the Survey, prior to publication in both official and unofficial works. During the past fiscal year the Committee ‘‘ considered 143 manuscripts, comprising a total of 21,614 pages and about 5,000 geologic names”’. Various card-catalogues bearing on nomenclature are kept up for the Committee, whose useful labours might well be followed in other countries. DECADE V.—VOL. X.—NO. VII. 21 322 Reviews—Cotteswold Naturalists’ Field Oak. Bulletin No. 471 (1912) consists of ‘‘ Contributions to Economic Geology (short papers and preliminary reports), Part II, Mineral Fuels”. The subjects dealt with are petroleum and natural gas, coal and lignite ; including gas in Alabama, petroleum and gas in Kentueky and Utah, petroleum in California and Wyoming, coal in North Carolina, Colorado, North Mexico, Utah, and Wyoming, lignite and coal in Montana, and lignite in North Dakota. These short papers and reports occupy, with index, etc., 663 pages, and they are accompanied by 62 plates (maps and sections) and 15 text-illustra- tions. They include topographic and geologic descriptions, records of borings, analyses, etc. Taking, for example, the report on the ‘‘ Geology of the San Juan Oil Field, Utah”’, by Mr. E. G. Woodruff, we learn that the oil-field is situated in the valley of the San Juan River in south-eastern Utah, that the area is part of the Colorado Plateau, consisting of much irregular and uneven ground, of which about 80 per cent is destitute of vegetation, and subject to erosion by the local and occasional, but copious, rains. There are two canyons with precipitous walls, about 1,400 feet deep, and possessing grand scenic beauty. More than 5,000 feet of strata ranging from Carboniferous to Jurassic are exposed in the field, and it is in the older strata, the Goodridge formation of the Pennsylvanian system, that the oil occurs. The oil is generally found in sand or sandstone, but small quantities occur in limestone. ‘The Goodridge Sand, 26 feet thick in places, is one of the most productive beds. Oil springs issue from different strata near the level of the San Juan River, the highest seeps in geological position being those from the Goodridge Sand, the lowest being in stratigraphic distance 1,450 feet below. The deepest well is 1,425 feet, but in some situations oil occurs at about 150 feet from the surface. It is noted that all the prolific wells are situated in synclinal strata, the - area being ‘‘ moderately complicated by north-south folds ”’. Bulletin No. 501 (1912) is on ‘‘ The Bonnifield Region, Alaska ’’, by Mr. S. R. Capps. The region contains productive auriferous placers and extensive lignite deposits; there are also possibilities of lode-mining. The report is well illustrated by photographie views and maps. XII.—Correswotp Naturauists’ Fretp Crus. ART I of vol. xviii of the Proceedings of this Club (19138) contains the address of the President, the Rev. Walter Butt, who dealt with some problems connected with Prehistoric Man, and concluded that the earliest safe evidence of man’s existence in the British Islands was in the Mousterian stage. Reports of various excursions contain much of geological interest, especially in reference to Droitwich, Cleeve Hill, Thornbury and Aust, Painswick and Kimsbury Castle, Bath and Box (the report on which contains a plan of the Box quarries). A more distant excursion was made to Bridport (outside the bounds of the Club), and the report is accompanied by some excellent photographic views of cliff scenery. The original articles include a paper, with one plate, on ‘‘ Some Reviews—Sulphur-mines in Sicily. 323 Inferior Oolite Brachiopoda”’, by Messrs. L. Richardson and C. Upton ; an account of ‘‘A Swallow-hole in the Inferior Oolite near Cheltenham’’, by Mr. Richardson; notes on ‘‘The Distribution of Calluna on the Cotteswolds”’, by Mr. H. H. Knight, who describes the relations of the heather to the soils and substrata; notes by Mr. Upton “On the abundant occurrence of Jnvolutina liassica (Jones) in the Lower Lias at Gloucester ’’—here we miss a reference to the paper on this subject by H. B. Brady (Gron. Mac., 1864, p. 193); a paper, with one plate, ‘‘ On the Stratigraphical and Geological Distribution of the Inferior Oolite Echinoids of the West of England (Supplement),”’ by Messrs. Richardson and EK. T. Paris; and a description of some ‘« Well-Sinkings on Lansdown, Bath”, by the Rev. H. H. Winwood, who refers to the attenuation of the Great Oolite, as indicated by the presence of Forest Marble. Particulars of that formation would be of interest, as it is not shown on the Geological Survey Map. Mr. Roland Austin has compiled a useful Index to the Proceedings of the Club (1846-1912). This replaces Mr. Richardson’s Index of 1904. XIII.—Lavoratione Rationale DELLE SoLFARE VIRDILIO E MINTINELLA. Monografia Technico-Economica. (A technical and economic Report upon the Sulphur-mines of Virdilio and Mintinella in Sicily: by Emmanvrtze Crimono, Engineer.) 4to; pp. 152, with 2 coloured plates. Palermo: Libreria Internazionale A. Reber, 1912. LONGSIDE the road between Naro and Campobello di Licata (Sicily) are the rich sulphur-mines of Virdilio and Mintinella, which form the subject of the elaborate and detailed monograph now before us. The object of this work is to present a rational scheme for the working of the sulphur, and the author hopes that it will be of permanent value, both scientific and economical. In configuration the sulphur-bearing basin has the shape of a wide horseshoe. The first part of this work is devoted to descriptive geological notes, in which the succession of the beds and mode of occurrence of the sulphur are described. The resemblance between the beds of Virdilio and Mintinella and those of other Sicilian localities is also discussed. Engineering reports connected with the difficulties encountered in working the deposits are contained in the second part, in which also are incorporated the opinions of various authorities on the causes that conduce to vibration and rock-fracture, and suggestions as to precautions that might be taken against catastrophes resulting therefrom. ‘Two schemes for working the mines are considered in detail: one for carrying on operations above ground, and another for underground working. The relative cost of either is discussed, and full calculations as to the amount of overlying material, of transport, excavation, banking, etc., have been included. Statistical tables and full details connected with the exploitation of the sulphur are con- tained in the last three parts of this monograph, which is illustrated by two good coloured plates of sections and plans. (324 Reviews—Brief Notices. XIV.—TuHe Resources or Tennessee. By A. H. Purpur and W. A. Netson. Vol. ii, No. 2, pp. 62-116, April, 1913. N this number A. H. Purdue contributes two short articles. One outlines the principles of water-supply for cities and towns, and is illustrated by a section showing the water-bearing strata at Etowah. The other points out the grave heed for eeological investigation of the foundations of large engineering structures. C. H. Gordon has written an account of the principal types of iron-ore deposits and their origin, with special reference to Tennessee. The deposits of limonite of Kast Tennessee are shown to be due to the weathering, probably in Tertiary times, of ferruginous limestones of Ordovician age. The hematite deposits are of two types: residual deposits, due to the leaching out by surface waters of calcium carbonate in ferruginous limestones; deposits of the Clinton type, in which the hematite occurs as beds of original deposition which have since undergone secondary enrichment. This paper contains four figures and numerous analyses. The discovery of Mastodon remains in a quarry near Nashville is recorded. The remains consisted of teeth and bones, and were found at a depth of 15 feet in a clay-filled solution channel in the Carters Creek Limestone. XV.—Brier Norices. 1. Instrrution or Minine anp Mrtatiturcy.—We have received the Presidential Address delivered on March 18, by Mr. Bedford McNeill, F.G.S8., before this Institution. He discusses the relations between mining and capital, the extension of mining, and makes especial reference to the relative and average annual production of gold and silver at various periods from 1493 to 1911. He also calls attention to the meeting of the International Congress of Mining, Metallurgy, Applied Mechanics, and Practical Geology to be held in London in 1915. The address is accompanied by an admirable portrait of the President. 2. Smart: Gepet Hamman Fartn.—Mr. G. W. Murray has an interesting note on the structure of this hill in the Catro Scventifie Journal, vol. vii, pp 21-4, February, 1913. The sea-face of Gebel Hamman Farin shows 45 metres of bedded basalt resting uncon- formably on variegated shales yielding many fossils, including Hemiaster. The basalt is overlain apparently conformably by 15 metres of Oyster limestones, among which Ostrea vestcularts is conspicuous. The evidence points to a contemporaneous flow in Santonian times. The hill is faulted down at its north-west end, and the basalts are not seen therefore at the point of previous interest, where the hot springs gush out amongst the beach shingles for some 400 metres. 3. CatirorntAN Tertiary Suarks.—Messrs. Jordan and Beal, having received a large collection of shark’s teeth from the Kern River, near Oil City, have been enabled to add several species to the fossil sharks of California. When describing these in the Bulletin of the University of California, 1918, they have taken the opportunity Reports & Proceedings—The Royal Society. 325 of giving a table of the geological range of Western American sharks from Triassic to Pleistocene. 4. Cattrorntan Eocens Motztusca.—A number of new forms of Kocene Mollusca have been described from the Marysville Buttes by R. E. Dickerson in the Bulletin of the University of California, 1913. The beds were deposited on a coarse-grained andesitic valley floor, overlain by gravels and sands (Ione Beds), which in their turn were capped with andesitic mud-flows, subsequently firmly cemented. The fauna is-considered to have accumulated in 100 fathoms under tropical or sub-tropical conditions. 5. FoRAMINIFERA OF SouTHERN CatiForNIA.—The Bulletin 518 of the Department of the Interior U.S. Geological Survey, 1912, is devoted to a description and illustration of the Plocene and Pleistocene Foraminifera from Southern California by Rufus M. Bagg. Over a hundred forms are described in ninety-two pages of text, and illustrated in twenty-eight plates by a series of excellent figures. That the author knows his subject is evident from the paucity of ‘n.spp.’ 6. BrptiograpHy oF Norta American GroLogy (PETROLOGY AND Miyeratocy) For 1911.—This useful work, compiled for 1911 by John M. Nickles, was published last year as Bulletin 524 of the Department of the Interior U.S. Geological Survey. It contains 1,266 entries, and has a first-class analytical index. 7. Patmozorc Seprments.—In the Journal of Geology (Chicago) for April-May, 1913, is a very suggestive paper by T. C. Brown on the origin of certain Palzozoic sediments. The author discusses the conglomerates, the oolites, and the interbedded sands of the Cambrian and Ordovician rocks of Center County, Pennsylvania. In the same Journal E. 8. Bastin has a paper on ‘‘Chemical Composition as a criterion in identifying Metamorphosed Sediments”’, which may be read in conjunction with the preceding. 8. Miocene Fauna or Eecensure.—Dr. F. X. Schaffer deals with this interesting fauna in the Abhandlung der k.k. geologischen Reichsanstalt, valk xxi, pt. 11( November, 1912). The paper includes the Gasteropoda, Cephalopoda, Crinoids, Echinoids, and Brachiopoda, and is fully illustrated. The fauna is singularly vich in Cerithium, Turritella, and Patella, and the occurrence of several species of Antedon is interesting. RHPORTS AND PROCHHDINGS.- I.—Tux Royan Socrery. June 5, 1918.—Sir Archibald Geikie, K.C.B., President, in the Chair. The Croonian Lecture was delivered by Dr. Robert Broom, C.M.Z.S., on ‘‘ The Origin of Mammals’’.? An endeavour is made to trace the evolution of mammals from Cotylosaurian ancestors through the carnivorous Therapsida. In 1 The accompanying abstract has been furnished by the author. 326 Reports & Proceedings—Geological Society of London. Upper Carboniferous times the line probably passed through some primitive generalized Pelycosaurs; in Lower Permian through primi- tive, probably Therocephalian, Therapsids. In Middle and Upper Permian the line passed through the Gorgonopsia. In, Triassic times the mammalian ancestors were small generalized Cynodonts. In Lower Jurassic the mammals are so Cynodont-like, and the Cynodonts so mammal-like, that in no single case are we absolutely certain which is which. In the Therocephalia, the Gorgonopsia, and the Cynodontia, the skull is very mammal-like. The zygomatic arch is, as in mammals, formed by the jugal and the squamosal. The teeth are divided into incisors, canines, and molars. In the later Gorgonopsians there is an imperfect secondary palate; in Cynodonts a complete secondary palate as in mammals. In Permian Therapsids there is a single occipital condyle; in the Triassic Cynodonts there may be a single condyle slightly divided or two exoccipital condyles. There is, on passing from earlier to later types, a steady increase in the size of the dentary and decrease in the size of the other elements of the jaw. The quadrate also becomes much reduced in the higher types. In Gorgonopsians and probably all earlier types the arch of the atlas is a pair of bones; in Cynodonts, as in mammals, there is a single arch. It is argued that the small Gorgonopsians fed almost exclusively on the comparatively slow-moving, small, herbivorous Anomodonts. In the Trias the small Anomodonts became very rare, and the carnivorous Therapsids had to feed on other small forms, apparently the more active lizard-like Cotylosaurs, such as Procolophon. The change of habit resulted in the Cynodontia. In Upper Triassic times the larger Cynodonts preyed upon the large Anomodont, Kannemeyeria, and carried on their existence so long as these Anomodonts survived, but died out with them about the end of the Trias or in Rhetic times. The small Cynodonts, having neither small Anomodonts nor small Cotylosaurs to feed on, were forced to hunt the very active long-limbed Thecodonts. The greatly increased activity brought about that series of changes which formed the mammals—the flexible skin with hair, the four-chambered heart and warm blood, the loose jaw with teeth for mastication, an increased development of tactile sensation, and a great increase of cerebrum. Not improbably the attacks of the newly evolved Cynodont or mammalian type brought about a corresponding evolution in the Pseudosuchian Thecodonts which ultimately resulted in the formation of Dinosaurs and Birds. I1.—Geotoeicat Socrery or Lonpon. (i) May 28, 1918.—Dr. Aubrey Strahan, F.R.S., President, in the Chair. The President, in referring to the loss which the Society had that day sustained by the decease of John Lubbock, 1st Baron Avebury, recalled the fact that Lord Avebury had been a Fellow of the Society for no less than fifty-eight years, that he had contributed several valuable papers to the Society’s Journal, and that he was the recipient Reports & Proceedings—Geological Socrety of London. 327 of the first Prestwich Medal. The President added that he felt sure that the Fellows would associate themselves with the resolution of condolence’ and sympathy which the Council had addressed to Lady Avebury. The following communications were read :— 1. ‘‘On the Age of the Suffolk Valleys; with Notes on the Buried Channels of Drift.” By Perey G. H. Boswell, B.Sc., F.G.S. The main watershed of Suffolk follows generally the Chalk escarpment, but keeps rather to the east of it, running in a north- easterly direction from Haverhill in the extreme south-west of the county. Suffolk forms a plateau, 100 to 400 feet O.D., dissected by a valley-system which is palmate in form, the chief rivers, taken from north to south, being the Waveney, the Alde, the Deben, the Gipping (with its estuary, the Orwell), the Brett, and the Stour. The Little Ouse and the Lark flow north-westwards into the Wash basin. _ The strata (Chalk, Lower London Tertiaries, London Clay, Crags, etc.) cut through by the valleys, and the mantle of glacial deposits (sands, gravels, and loams, Upper Boulder-clay, and morainic gravels), which more or less covers the whole county, are described briefly. Reasons are given for thinking that the Contorted Drift does not extend far south of the Waveney. The valleys, although they may have been etched earlier, are on direct evidence post-Pliocene in age; but, by analogy with the Waveney and the Norfolk rivers, they may be younger than the Contorted Drift. The Upper Boulder-clay (=the Great Chalky Boulder-clay of S. V. Wood, jun.) covers much of the plateau, and wraps down into the valleys in a very characteristic manner.’ The glacial Sands, etc., below it also appear at times to lie on the valley-slopes. Intense glacial disturbances are found to be situated always on ‘bluffs’ or ‘spurs’ of the plateau projecting into the wide open valleys, which were thus in existence before the advent of the valley glaciers to the action of which the disturbances have been attributed. In each of the main valleys occur one or more buried channels of Drift; borings made recently allow these to be described in detail, and the deposits filling them to be discussed. A contour map of the top of the Chalk is prepared for the county, and this serves to bring out the anomalies in the valleys. These buried channels were probably eroded by sub-glacial water-streams, and a comparison is instituted between them and the Fohrden of North Germany, Schleswig- Holstein, Kerguelen, etc., described in detail by Dr. Werth and others. | The evidence, therefore, indicates that the pre-Glacial or early Glacial contours of Suffolk were in the main much as they are now. The form of the rivers and valleys suggests that some amount of capture may have taken place before the deposition of the Upper Boulder-clay; and that the present river- yescue is recovering from a state of arrested development, due to the ‘overloading’ of the valleys with Drift deposits and torrential debris during the last glaciation of the area, and to the subsidence (some 60 to 80 feet) which followed it. 328 Reports & Proceedings—Geological Society of London. 2. ‘The Internal Structure of Upper Silurian Rugose Corals from the Grindrod Collection, Oxford Museum.”’ By Donald Esme Innes, B.A. (Communicated by Professor W. J. Sollas, Sc.D., F.R.S., F.G.S.) In this paper the following genera and species are described :— Paleocyclus porta, P. fletchert, P. rugosus. Cystiphyllum siluriense, C. cylindricum. Cyathophyllwm (?) : a new species. Cyathophyllum articulatum, C. truncatum. Strombodes murchisoni, Str. typus, Str. diffluens. The new species of Cyathophyllum (?) is of especial interest. It was figured by Milne Edwards & Haime as Cystiphyllum ecylindricum, Lonsdale; with which it has no close affinities. It combines characters of the Silurian Cyathophylla and Hallie with those of the Lower Carboniferous Caninie. Particular attention is paid to the construction of a septum in the various genera, the following types being well represented :— (1) Radial spines on the vesicles, with their bases often connected by a web. Example: Cystiphyllum. (2) Rods placed in juxtaposition and cemented together. Example: Paleocyclus. (3) Simple plates. Example: Cyathophyllum articulatum. (4) Crumpled plates. Example: Cyathophyllum (?), the new species. (5) Plates with backward costal prolongations. Example: Strombodes. Comparison of the Upper Silurian coral facies with that of the Lower Carboniferous shows that Cystiphyllum, in its vesicular and spinose structure, bears a close resemblance to the compound Michelinia, while Strombodes is allied in structure to Cyathophyllum regium of the Viséan. (ii) June 11,1913.—Dr. Aubrey Strahan, F.R.S., President, in the Chair. The following communications were read :— 1. ‘Certain Upper Jurassic Strata of England.” By Dr. Hans Salfeld, University of Gottingen. (Communicated by S. S. Buckman, F.G.S.) The writer has studied the Upper Jurassic strata of North- Western Germany, the Boulonnais, and Southern England with special reference to the Ammonites and their zones. The results of his labours are to be published in detail; but, in anticipation, he offers to the Society an epitome of his conclusions with regard to the English strata. The localities with which he deals are the Dorset coast from Kimmeridge to Abbotsbury, and the Wiltshire exposures at Swindon and Westbury, with an incidental reference to Market Rasen. The formations concerned are the Portlandian, Kimmeridgian, and for a starting-point the Upper Oxfordian: these terms being employed in the German sense. ‘The Upper Oxfordian=upper part of the English » Corallian (+Kimmeridge Clay loeally) is divided into three zones, found at Osmington, Westbury, and Swindon. The Kimmeridgian is divided into five zones, and is equal mainly to the Lower Kimmeridge Clay of English authors, with one important exception ; | | Reports & Proceedings —Geological Society of London. 329 the Abbotsbury Iron-ore is placed as the second zone of the Kimmeridgian, and is correlated with the Market-Rasen Clays. The Portlandian is divided into nine zones; but the term as used in the paper includes the Portland Oolites, Portland Sands, and Upper Kammeridge Clay of English authors. Three new genera of Ammonites are named, and two new zonal species of Ammonites are defined. 2. ‘The Volcanic Rocks of the Forfarshire Coast and their Associated Sediments.” By Albert Jowett, M.Sc., F.G.S. The peculiar intermingling of fine sediments with the Lower Old Red Sandstone lavas of Scotland is well known from the writings of Sir Archibald Geikie. The author has found that in Forfarshire these sediments are frequently amygdaloidal, the production of the cavities having been accompanied by the buckling and fracturing of the layers of sediment. It is suggested that such effects may result from the pouring of molten rock over wet unconsolidated sediment : steam being produced within the sediment, but unable to escape owing to the presence of the overlying rock. The surface of the sediment was apparently ploughed up by the lava, the lower portion of which occasionally contains rounded nodules of hard amygdaloidal sediment. The sediment is sometimes slightly altered where in contact with the volcanic rock. Further evidence of the pouring of molten rock into water is furnished by the occurrence of a rude pillow-structure in some of the lavas. Several lenticular conglomerates are interbedded with the volcanic rocks, resting upon eroded surtaces of the latter. The conglomerates consist of large rounded blocks of volcanic rock, enclosed in a matrix composed almost entirely of volcanic debris. Most of the volcanic rocks are olivine-basalts, rhombic pyroxene as well as olivine sometimes being present. Some contain rhombic pyroxene to the exclusion of olivine. A few porphyrite dykes of Lower Old Red Sandstone age are intruded in the lavas. The fine sediments consist of a variable proportion of quartz and mica and a little felspar, together with chlorite, iron oxides, and occasional minute fragments of volcanic rock. Calcite, quartz, chalcedony, and chlorite are the commonest minerals in the amygdules, in both lavas and sediments. In the south-west of Lunan Bay, a mass of Upper Old Red Sandstone with a basal conglomerate has been found resting unconformably upon the Lower Old Red Sandstone volcanic rocks. 3. “On a group of Metamorphosed Sediments situate between Machakos and Lake Magadi in British East Africa.” By John Parkinson, M.A., F.G.S8. That part of British East Africa which borders the Athi Plains and extends westwards to the eastern edge of the Rift Valley, is undulating country composed of foliated rocks of ancient appearance, crossed by pegmatites which are unconnected with any apparent granitic intrusions. 330 Reports & Proceedings—Mineralogical Society. A series of crystalline rocks, for which it is proposed to use the name Turoka Series, is situated just below the great lava plateau of the Kapiti Plains, and forms the ground drained by the head-waters of the Turoka River. The following rock-types are present in the chief section, in the following apparent upward succession :— (1) Hornblende-schist, seen to a thickness of 3ft. Sin. ; (2) flaggy and impure marble, 3 feet; (3) biotite-gneiss, 2 feet; (4) cale-mica rock with lenticles of biotite-gneiss, 3 ft. 8 in.; (5) hornblende-schist similar to No. 1, 1 foot; (6) impure cale-rock, 2 feet; (7) quartz-felspar vein, 2 feet ; (8) hornblende-schist, 2 feet ; and (9) impure cale-rock, resembling No. 5 and about 4 feet thick. A detailed petrographical description is given of the various rock- types present in the series, which, in addition to those mentioned above, includes kyanite-garnet-gneisses and a scapolite-garnet rock. The author concludes that the group represents a series of metamorphosed arenaceous and calcareous sediments, and that there is a complete passage from calc-mica rocks into biotite-gneisses. MINERALOGICAL SocrEery. June 17.—Dr. A. E. H. Tutton, F.R.S., President, in the Chair. W.L. Bragg: Crystal Structure as revealed by Rontgen Radiation. An analysis of the diffraction patterns obtained when X-rays traverse a section of a crystal shows that in many simple crystals the diffraction is caused by a set of points arranged on a space-lattice. This is the case when the molecule contains either a single heavy atom of at least twice the atomic weight of the other constituents, or only two atoms of nearly the same atomic weight. By comparison of the pattern given by certain alkaline halides, such as KCI and KBr, a definite structure of these cubic crystals is clearly indicated, and it would appear that the atoms are arranged on a space-lattice whose elementary parallelopiped is a cube, alternate atoms being along the axes, so that atoms of one kind form a face-centred cubic space- lattice. These conclusions are confirmed by a comparison of the distances between planes parallel to the various faces of these crystals carried out by means of the X-ray reflection-spectrometer, and it appears that a single atom is associated with each point of the space- lattice which diffracts in the case, for instance, of the alkaline halides, calcite, fluor, blende, and pyrites. If the suggested structure of the erystals is correct, a simple calculation gives the absolute wave- length in centimetres of the homogeneous components in the X-ray beam from a platinum anticathode.—H. V. Ellesworth: The Crystal Habit of Topaz from New Brunswick, Canada. , Topaz, a rare mineral in Canada, occurs in York Co., New Brunswick, associated with wolframite, molybdenite, and a little fluor. On the crystals the forms 110, 120, 011, 112 are prominent, but other pyramid and prism forms are sometimes present, sixteen forms altogether being observed. Dull faces were coated with silver by Brashear’s process, in which an ammoniacal solution of silver nitrate is reduced by a sugar solution.—Dr. G. T. Prior: On the Meteoric Stone which fell at Baroti, Punjab, India, in September, 1911. The stone, Reports & Proceedings—Zoological Society of London. 331 which belongs to the ‘intermediate chondrite’ group of Tschermak’s classification, was found on analysis to contain about 9 per cent of nickel-iron and 7 per cent of troilite, which were disseminated in small particles through a colourless matrix of enstatite and olivine showing only few chondrules.—Dr. A. W. Gibb exhibited kimmererite from Unst, Shetland Islands. ITV.—Zootoetcat Soctery oF Lonpon. May 20,1913.—Professor E. A. Minchin, M.A., F.R.S., Vice-President, in the Chair. Dr. R. Broom, C.M.Z.S., read a paper ‘‘On the South African Pseudosuchian Reptile Huparkerva and allied Genera”. Besides giving an account of the very completely known South African form, he also discussed the structure of the Elgin allied forms, Ornthosuchus and others. The group of Pseudosuchians he regarded as an extremely important primitive reptilian order, as there is good reason to believe that not only does it contain the ancestor of the Dinosaurs, but also the ancestors of the Pterodactyles and Birds. Huparkeria and Ornithosuchus are, in structure, almost Dinosaurs, and it is held that when the bipedal habit was more fully acquired the few characters not quite Dinosaurian would’ become Dinosaurian. Birds are held to have originated from a Pseudosuchian which, by a bipedal habit, had acquired a Dinosaur-like hind limb, and had then become arboreal in habit and acquired the peculiar power of flight. June 8, 1913.—Professor E. W. MacBride, M.A., D.Sc., F.R.S., Vice-President, in the Chair. A paper on ‘‘ Some Miocene Cirripedes of the genera Hexelasma and Scalpellum from New Zealand”, communicated by Dr. W. T. Calman, F.Z.8., was read by Mr. T. H. Withers, F.G.S. An account is therein given of the ‘ gigantic Cirripede’ of New Zealand, originally described as Scalpellum aucklandicum, of which remains have long been known to occur in the Waitemata Beds (Miocene) of Motutapu Island, Auckland Harbour. The valves of this Cirripede attain a length of 8 inches, and have been previously supposed to belong to a pedunculate form, but while Sir James Hector (1887) referred them to the genus Scalpellum, Professor W. Blaxland Benham (1903) thought that they approached more closely to the genus Pollicipes. From a study of the original material collected by Professor James Park (1887). it is now shown that this Cirripede is a sessile form allied to Balanus, and it is referred to Dr. P. P. C. Hoek’s recently instituted genus Hexelasma (1903). A smaller undetermined species of Hexelasma and a new species of Scalpellum (sensu lato) are also described. These are in the collection of the Geological Survey, New Zealand, and occur in the same beds as the ‘ gigantic Cirripede’. A second new species of Scalpelium is founded on some valves from New Zealand, and a restoration is given, the remains being sufficient to justify their reference to the sub-genus Arcoscalpellum, Hoek. 1 GEOL. MAG., 1903, p. 110, Pls. IX, X. | 332 Obituary——Thomas Francis Jamieson. Oe ET iOeASay ea THOMAS FRANCIS JAMIESON, LL.D., F.G.S. BorRN APRIL 26, 1829. DIED May 24, 1913. We regret to record the death of T. F. Jamieson, of Ellon, Aberdeenshire, distinguished for his researches on the glacial geology of Scotland. The results of his earliest geological work and of all his more important subsequent observations were com- municated to the Geological Society of London, introduced in the first instance by Murchison in 1858. Four years later Jamieson was elected a Fellow of the Society, and in 1898 he was awarded the Murchison Medal by the Council. On that occasion, although unable to be present, he wrote expressing his gratification and his ‘‘ recollection of the warm-hearted Sir Roderick’’, from whom he had received much kind attention and help many years ago when a young man. Jamieson was born at Aberdeen, and educated at Marischal College during the years 1843-6, but he did not graduate. His energies were now devoted to rural economy. For many years he was Factor on the Ellon estate, and subsequently took the farm of Mains of Waterton, and became widely known and respected as an expert in agricultural matters. In 1862 he was appointed Fordyce Lecturer on Agricultural Research in the University of Aberdeen, his services being recognized in 1884 by the conferment of the honorary degree of LL.D.!. Meanwhile his leisure time was occupied with studies of the various Drift deposits and the effects of glacial action. In his first paper, on the ‘‘ Pleistocene Deposits of Aberdeenshire’ (read in 1858), he described various mounds and ridges of gravel and the shells from the drifts, which in his opinion were accumulated at a time when the land was 450 feet lower. Subsequently it stood higher than it does now. In another paper (1860) on the ‘ Drift and Rolled Gravel of the North of Scotland’’, he dealt more fully with the Pleistocene phenomena, and for the first time brought forward detailed evidence relating to the land-glaciation of Scotland, to the fluting, grooving, and scratching of the rocks, the dispersion of boulders, ete. Interesting observations were also recorded on the positions assumed by pebbles in streams. In the same year he drew attention to the occurrence of characteristic Crag shells in the Drift of Aberdeenshire, and regarded the evidence as indicating a patch of Crag preserved in situ. In 1882, in a further account, he gave reasons for believing that the shells were derived. In 1862, in a paper on the ‘‘ Ice-worn Rocks of Scotland’’, he pointed out the great ercsion by ice-action, and the presence of boulders far above their parent rocks. He illustrated his remarks on land-ice by reference to phenomena in Greenland and on the Antarctic continent, and gave a sketch-map of Scotland showing the direction of the glacial markings. 1 For these particulars we are indebted to the Aberdeen Free Press, May 26, 1913. Obituary—Thomas Francis Jamieson. 333 In 1863 his great paper on the ‘‘ Parallel Roads of Glen Roy ”’ was published, and therein he showed that they are beaches of freshwater lakes, which originated from glaciers damming the mouths of valleys and reversing their drainage. The date of the lakes he regarded as posterior to the great land-glaciation of Scotland. As remarked by Lyell (Antiquity of Man, 4th ed., p. 305), Mr. Jamieson ‘‘ observed many facts highly confirmatory of the theory of glacier-lakes’’, which had been previously suggested by Agassiz and Buckland, and ‘‘ showed that this theory affords a complete explanation of all the most striking peculiarities ’’.’ In 1891 he published ‘‘Supplementary Remarks on Glen Roy’’, dealing with subsequent explanations and further supporting his original views. In 1865 he read an important paper on the ‘‘ History of the Last Geological Changes in Scotland”. In this he referred to evidence of the Mammoth having inhabited Scotland before the Glacial period. He noted the enormous thickness of the land-ice, Schiehallion (3,500 feet high) being glaciated near to the top as well as on its ‘flanks. He considered that the ice was developed as a thick cake and flowed off ‘‘ not so much on account of the inclination of the bed on which it rested ’’, but ‘‘in the way that a heap of grain flows off when poured down on the floor of a granary . . . given a floor of infinite extension, and a pile of grain of sufficient amount, the mass would move outward to any distance”. He concluded that ‘‘the waat of much inclination in the surface of a country, and the absence of great Alpine heights, are therefore objections of no moment to the movement of land-ice, provided we have snow enough”’. He further noted how the Boulder-clay varies in colour and character according to the rocks from which it was derived, and he expressed his opinion that certain kaims (or kames) may have been formed by the ridging-up of gravel in front of a glacier. Finally, he discussed the introduction of the plants and animals into the British Isles since the Glacial period, admitting that ‘‘ice might have formed a bridge to some, but not to the greater part’’. This paper contains a long list of Glacial shells. In 1866 he described the ‘‘ Glacial Phenomena of Caithness’’, and in 1874 he dealt with the ‘‘ Last Stage of the Glacial Period in North Britain ’’, discussing the formation of kaims and eskers, and advocating the development of a second ice-sheet, but not so thick nor so extensive as that in the earlier glaciation. In 1882 he read a paper on the “‘ Red Clay of Aberdeenshire ’’, considering that it was laid down before the last advance of the glaciers. We need only further mention that Mr. Jamieson on two occasions entered other geological fields, writing in 1861 on the ‘‘ Structure of the South-West Highlands of Scotland (parts of Bute, Cowal, and Jura) ’’, and in 1871 on the ‘‘ Older Metamorphic Rocks and Granite of Banffshire’’, when he advocated the metamorphic origin of the granite, and was supported by Ramsay.’ He Bee 1 See also EH. B. Bailey, Proc. Geol. Assoc., xxii, 203, 1911. 2 Seventeen papers, from 1865 to 1908, are credited to Mr. T. F. Jamieson in the GEOLOGICAL MAGAZINE.—ED. 334 Obituary—The Right Hon. Baron Avebury. THE RIGHT HON. BARON AVEBURY, DiCsLs, DL D,, ER.S.,. FS. FGost, aa Born APRIL 30, 1834. DIED MAY 28, 1913. In the death of Lord Avebury natural science has lost one of its most enthusiastic and cultured disciples. Born at Eaton Place, London, he was the son of Sir John William Lubbock, 8rd Baronet, F.RS., F.G.S., a distinguished mathematician and astronomer, who died in 1865. John Lubbock succeeded to the baronetcy in that year, and was created Baron Avebury in 1900. He received a school education at Eton, but no University training, as his services were wanted before he had attained the age of 15 in the banking-house of Robarts, Lubbock & Co., Lombard Street, an establishment of which his father was then the Head. John Lubbock became a partner in the firm in 1856 and succeeded to the chief position on the death of his father. It will be unnecessary here to refer in particular to his great business capacity and to the services he rendered to commerce, the arts, and to education in general. As a Member of Parliament he represented Maidstone and afterwards the University of London, taking an active part in promoting the Ancient Monu- ments Act, the Open Spaces Act, and many other measures. Interest in the study of natural history was developed in Lubbock at an early age, and the proximity of his home at High Elms, near Farnborough, to that of Darwin at Down, in Kent, no doubt greatly influenced the character of his recreative pursuits. In course of time he acquired a wide range of knowledge in archeology, entomology, botany, and geology, and we may be content here to refer to his researches on the first and last of these subjects. One of his earliest discoveries, made in 1855 in company with Charles Kingsley, was that of the skull of a musk-ox in a gravel-pit close to Maidenhead railway station, and the specimen was described by Owen in the following year as the first example which had come under his notice from a British locality. In 1860 and again in 1862 and 1863 he joined Prestwich and others in excursions to the flint- implement-bearing districts of Amiens and Abbeville, and in 1861 he spent a holiday in Switzerland with Tyndall and Huxley. The knowledge thereby obtained stimulated those further studies which led in one direction to the publication in 1865 of Lubbock’s Pre- historic Times, as illustrated by Ancient Remains and the Manners and Customs of Modern Savages.. This work was followed in 1870 by The Origin of Civilisation and the Primitive Condition of Man. Both works have attained to the sixth edition. It may further be mentioned that he was associated with Huxley, Busk, and others as one of the editors of the Natural History Review (1861-5). In 1867 he brought before the Geological Society a paper ‘‘On the Parallel Roads of Glen Roy”, advocating their formation in a lake, the waves in which did not arrest but threw down to lower levels the angular debris of the hill-slopes. His interest in Switzerland led to many journeys to that country and to the publication in 1896 of Zhe Scenery of Switzerland and the Causes to which it is due. OF this work a fourth edition has been issued. A companion volume on Obituary—Herbert Kelsall Slater. 335 The Scenery of England and the Causes to which it is due was published in 1902, and the subject, beautifully illustrated, clearly expounded, and treated in an enthusiastic spirit, made the work so popular that it has reached a fifth edition. In 1903 Lord Avebury gave to the Geological Society the results of ‘‘An Experiment in Mountain-building’’, based on apparatus which produced compression in two directions. The features thus produced on pieces of carpet-baize and alternating layers of sand were illustrated in his short published account of the phenomena. He was elected a Fellow of the Geological Society in 1855, and in 1903 the Council awarded to him the first Prestwich Medal. He was elected a Fellow of the Royal Society in 1858, and became a Trustee of the British Museum in 1878, taking a warm interest in its affairs, and especially in the Natural History branch, afterwards established in South Kensington. He was chosen president of many societies representing diverse scientific and practical subjects, among them the Linnean, Royal Microscopical, Ray, Entomological, and Statistical Societies, and the Anthropological Institute. As the representative of many sciences he was fitly selected to preside over the jubilee meeting of the British Association held at York in 1881. Lord Avebury was twice married, his second wife being daughter of General Pitt-Rivers, F.R.S. He died at his seaside residence, Kingsgate Castle, near Margate, and was buried on May 31 at Farnborough churchyard, Kent. He is succeeded in the Peerage by the Hon. John Birkbeck Lubbock, his eldest son. HERBERT KELSALL SLATER, F.G.S. Born AUGUST 28, 1875. Drep May 2, 1913. WE regret to record the death from snake-bite of Mr. Herbert Kelsall Slater, F.G.S., Assistant Geologist and Acting Second State Geologist to the Mysore Government. He was the son of the Rev. T. E. Slater, a well-known missionary in Mysore, and was educated at Bishop’s Stortford College, Herts, and the Central College, Bangalore. In October, 1894, he joined the newly formed Mysore Geological Department under Mr. Bruce Foote, and afterwards served under his successors, Dr. J. W. Evans and Dr. W. F. Smeeth. He had already acquired a competent knowledge of geology in India when he returned to England in 1901 and studied at the Royal College of Science under Professor J. W. Judd. In 1909 he again visited this country for purposes of study, and afterwards spent some months in Canada and made himself familiar with its crystalline rocks, as these present many points of similarity to those on which he was working in India. He mapped a con- siderable portion of Mysore, especially in the Shimoga, Tarikere, and Kadur Districts, which lie in the north and west of the State, and brought an independent mind to the problems that presented themselves. His work will be found in the Records of the Mysore Geological Department. See vol. ii, pp. 118-80, 1899; vol. iii, pp. 148-62, 1901; vol. iv, pp. 119-46, 1903; vol. v, pt. ii, pp. 35-56, 1904; vol. vi, pt. u, pp. 5-26, 1905 (‘intrusive’ and ‘corrosive’ 336 Obituary—Lester Frank Ward. quartz); vol. vii, pt. ii, pp. 1-20, 1906 (describing a remarkable conglomerate in'the schists between Birur and Tarikere); vol. viii, pp. 31-72, 1907 (iron-bearing rocks associated with charnockite) ; vol. ix, pp. 35-72, 1908 (banded magnetite quartzites). He also reported to the Government on various metalliferous deposits and building stones. On the morning of his death, Mr. Slater was at a short distance from his camp near Tirthahalli, in the Shimoga District, when he trod upon a large snake, which coiled itself round his boot and bit him repeatedly under the knee through stout cord breeches. Death took place some twelve hours later. Mr. Slater leaves a widow and three young children. J. W.E. LESTER FRANK WARD, A.M., LL.D. WE learn from Nature that Dr. Lester Frank Ward, A.M., LL.D., Professor of Sociology at Brown University, Providence, R.I., and formerly Palontologist of the U.S. Geological Survey, died in Washington on April 18, in his 72nd year. He was born in 1841 at Joliet, Illinois, and was known to geologists more especially by his researches on the Flora of the Laramie Group, which he regarded as having equally Upper Cretaceous and Lower Tertiary affinities. ERNST ANTON LEOPOLD KITTL. BORN DECEMBER 2, 1854. DIED May 1, 1913. Tue death is announced of Professor Ernst Kittl, who was for many years associated with the geological and paleontological department of the Imperial Court Natural History Museum of Vienna, first as assistant and ultimately as director. In 1885 he published two papers on the Lower Pliocene Mammalia of Maragha, Persia, and during subsequent years he prepared numerous other important papers on fossils, chiefly Mollusca. He also wrote a Guide Book to the Geology of the Salzkammergut, for the use of the International Geological Congress which met in Vienna in 1903. WILLIAM FOX, M.INST.C.E. WE regret to record the death on June 14, aged 66, of William Fox, M.Inst.C.E., M.Inst.Mech.E., an eminent waterworks engineer, whose labours naturally brought him into association with various geological problems. For many years he was a Fellow of the Geological Society, but had recently resigned. MISCHLILAN HOUVUS. Mr. Caartes Panzerra Carwin, of the Geological Department of the British Museum (Natural History), has been appointed Assistant Librarian to the Geological Society of London. Mr. Chatwin carries with him the cordial wishes of his friends, who feel that his many qualifications will in time allow him to settle down into a long career of usefulness to the Fellows of the Society. BRITISH MUSEUM (NATURAL HISTORY) NEW PUBLICATIONS (continuea). Catalogue of the Collection of Birds’ Eggs in the British Museum (Natural History). Vol. V. Carinatee (Passeri- formes completed). By W. R. Ogruvie-GRANT. 8vo. pp. xxiii, 547, with 22 coloured plates. Cloth. £2 7s. 6d. Catalogue of the Chzetopoda in the British Museum (Natural History). A. Polycheta.—Part I: Arenicolide. By J. H. ASHwortH. Roy. 8vo. With 15 plates. Cloth. 27s. 6d. MILLER (G.S.). Catalogue of the Mammals of Western Europe (Europe exclusive of Russia) in the Collection of the British Museum. 68vo. pp. 1034, with illustrations. Cloth. 26s. History of the Collections contained in the Natural History Departments. Vol.II: Appendix, Zoology, 1856 to 1895. By Dr. A. GUNTHER. 8vo. pp.118. Cloth. 5s. A Descriptive Catalogue of the Marine Reptiles of the Oxford Clay, based on the Leeds Collection in the British Museum (Natural History). Part II. pp. 280; 78 text- figures and 14 plates. 4to. Cloth. £1 5s. Part I, 1910. 4to. pp. 228; 94 text-figures and 11 plates. Cloth. £1 5s. 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KINDLE, Geological FP. Mennell’s Manual of Petrology 375 Survey of Canada. (Plate XI and A. Holmes: Age of the Harth . 376 a Text-figure.) ... .. 387 | §. 8. Buckman’s Yorkshire ae : Micropholis . Stow, Huxley. By 2 Ammonites . On D. M. S. Watson, M.Sce., Uni- Brief Notices : Yorkshire Phil. Soc. - versity College, London. ee —Cambridge Phil. Soc.—South 5 Text- figures.) Sees ... 340 African Vertebrata—Pleistocene Psalidocrinus stramber gensis, by Geology, New York — North Dr. M. REMES; and P. reme%i, American Camels—Trachodon— by Dr. F. A. BATHER, H.R.S. Road-metal ... . 378 (With 8 Text-figures.) ... ... 346 Rochdalia Parkert. By HENRY : OD WD, oie ROR III. CORRESPONDENCE. (With 2 Text-figures.) ... ... 8352 | R. M. Brydone ... 380 Cretaceous of Bahia, Brazil. By A. R. Horwood . 881 JOSEPH MAWSON, F.G.S. (With a Map.)... . 356 Earn Structure. ByJ. E. Topp, Me OBITUARY: M.A., University of Kansas. 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A= Dar Siaus. . 4to. 2 Clothe ee Vol. Il E—K. 1904. 4to. Cloth. £1, Voli] Te Ot910- 4to. Chotheeeae Vol. TV. . P—SN; — 19138. 4to. ‘Cloth -éi- My Piety zt henna OR GEOL. Maa. 1913. PLATE XI. Portion of a trunk of Lepidodendron veltheimianum, Sternb., from French, Lick, Indiana. 4 nat. size. THE GEOLOGICAL MAGAZINE NEW SE RiESw in DEGAD EM WD WOE. XK: No. VIII.—AUGUST, 1913. ORIGINAL ARTICLIES. I.—Nore on a Process oF FossirizaTIonN IN THE PALmozorIc Lycorops.! By H. M. KINDLE, Department of Mines, Geological Survey of Canada, Ottawa, Ontario. (PLATE XI.) _ i OST collections of fossil plants include specimens of tree-trunks or branches in which the bark is preserved in great perfection, while no trace of the structure of the trunk within the bark remains. Striking examples of this type of fossilization, in which the bark is preserved in exquisite detail while the space within the bark is wholly filled with fine siliceous sediments showing no trace of the original plant structure, occur frequently among the various species of Srgillaria and Lepidodendron. The fossilized armour-like outer cortex of Lepidodendron fails to retain any remnant of the inner woody material about as often as the various molluscan species of Spirifer fail to preserve their delicate internal spires. We know from the silicified specimens which have been found that the greater part of the trunk in Lepidodendron is occupied by a soft middle cortex which is very readily disposed of by micro-organisms. The relatively small cylinder of secondary wood which is found in most species which have attained to a large growth was itself rather susceptible to decay, the tracheids being relatively thin-walled, with the medullary cells very large and the rays voluminous.?, Innumerable examples of the entire failure of the woody tissue of these Lycopods to survive the processes which left the outer cortex admirably preserved occur in the fine-grained sandstones of Pottsville: age in Orange County, Indiana. These beds, which have long been quarried for the manufacture of whetstones, contain numerous fossil trunks of Zepidodendron velthermianum, Sternb. (Plate XI), which show the carbonized bark in a good state of preservation, while the space inside the bark is wholly filled with very fine sand similar to that of the strata in which the fossils he. These sand-filled tree-trunks generally retain approximately their original outline, except for a slight flattening of the trunk. Two trunks of Lepidodendron about 10 inches in diameter and 8 feet in height were observed at the time of my visit standing upright in | one of the whetstone quarries. The largest trunk seen had a circum- ference of 4 ft. 8in. The usual size of the trunk is 6 to 15 inches in 1 Published with the permission of the Director of the Geological Survey of Canada. * Letter to the author from David White. DECADE V.—VOL. X.—NO. VIII. 22 338 EH. M. Kindle—Fossilization of Paleozoic Tree-trunks. \ diameter. None of the trunks observed in the whetstone quarries, whether large or small, showed any trace of woody tissue within the bark, which was usually altered to coal. Similar sand-filled trunks of Leprdodendron and Sigiliaria have been described by Dawson from Joggins, Nova Scotia, and by various geologists from other localities. The exact conditions under which the substitution of sand for woody tissue within the bark occurred during the fossilization of the latter have, so far as the writer is aware, never been illustrated by examples from our present forests. Rational explanations of the obscure phenomena of the past are often facilitated by means of the analogy supplied by existing agencies. I may therefore venture to call attention to the remarkable resistance to decay of the bark of the common canoe-birch and the equally striking susceptibility to decay of the wood of this tree. Consideration of the differential rate of decay of the bark and the wood of the birch throws much light on the process which has so often produced the kind of fossilization represented by the sand-filled bark of the Lepidodendron. The decay of wood is essentially a biological process resulting directly from the metabolism of the fungi and bacteria which gain access to it. But since moisture and free oxygen are essential to the life of these organisms, wood kept either in a very dry atmosphere or under water is practically immune from decay. The protective agency of water is illustrated by the fact that many of the oak piles in a certain town in Wales which were used in the construction of a dock five hundred years ago are still doing service. It seems clear that the degree of resistance of various kinds of woods to decay depends primarily not upon the texture of the woody tissue but upon the presence or absence of substances in it which fail to support or are directly harmful to the life of destructive fungi. Thus pitch and resin in the soft wood of the conifers and tannin in the cells of the oak are unfavourable to the growth of fungi. During life the bark of all trees is highly resistant to colonization by either fungi or bacteria, and until broken affords complete immunity from their attacks on the enclosed wood. After the death of the tree, however, the bark in many species loses the qualities which made it while the vital processes were active immune to the vital activities of fungi and micro-organisms, and decay may proceed in it much more rapidly than in the wood. This is true in the case of the walnut, beech, tulip, and many other trees where the bark completely decays or breaks up into small fragments while the wood is still in a good state of preservation. In the case of the birch, however, the immunity to decay which characterizes the bark of all living trees persists to a remarkable degree after death. So great is this resistance in the canoe-birch, Betula papyracea, that the wood may completely disappear while the bark is still in a perfect state of preservation and retains the original shape of the tree-trunk. The photograph (Text-figure) shows a section of the bark of a birch-tree from Manitoba in which the wood had almost completely decayed and disappeared. This bark shell which retained but a trace of decomposed woody dust, however, is wholly untouched by decay, . and similar examples may be observed wherever birches flourish. E. M. Kindle—Fossilization of Paleozore Tree-trunks. 339 Another section of a small birch-tree represented by perfectly pre- served bark from which the wood had wholly disappeared illustrates well the possibilities which the birch affords for the formation of sand-filled fossil tree-trunks similar in their general features to those of the Paleozoic Lycopods. This was found nearly filled with sand and partially buried in a river bar. The density of the bark of the birch is such that a section of it remains almost completely submerged when in the water. ‘his characteristic would facilitate its speedy sinking and burial in sediment whenever subjected to fluvial action. The birch-bark specimen shown in the figure has suffered a slight flattening, resulting from the decay and removal of the supporting wood. Itshould be noted that this slight flattening of the birch-bark is duplicated very often in the fossilized trunks of Lepidodendron. The Section of the bark of the trunk of the canoe-birch from which the wood has completely decayed, but leaving the bark in a nearly perfect state of preservation. partially sand-filled section of birch-bark just alluded to clearly illustrates how perfectly one of the trees of our present flora combines in itself characteristics which would lead to the same kind of fossilization so often met with in Lepidodendron. Observations of the empty bark shells of decayed birch-trees in the Canadian forests can hardly fail to convince one that Lepidodendron possessed a bark which, like that of the birch, far outlasted the woody interior. It appears most probable that the bark cylinders of the fossil Carboniferous Lycopods were generally hollowed out by rapid decay of the wood and then filled with sediment before fossilization began, just as empty birch-bark 340 D. M.S. Watson—On Micropholis Stowi, Hualey, tree-trunks are now being prepared for fossilization in Canadian lakes and rivers.' { Wote.—Excellent sound timber for gate-posts and other agricultural purposes is obtained both in Scotland and Ireland from the perfectly preserved bog-oak and other trees found in the peat. The piles of the Swiss lake-dwellings (of Stone and Bronze age) testify by their soundness the durability of wood under water, the only important change being their blackened condition.—Ep. | EXPLANATION OF PLATE XI. Portion of a trunk of Lepidodendron velthevmianum, Sternb., from French, Lick, Ind. 4 nat. size. The specimen represents a mould composed of fine siliceous sediments which have been deposited inside a section of empty bark trunk. A portion of the original carbonized bark which still adheres to the mould is seen in the dark irregular patches. Il.— WUicrorzoris Stow, Huxtry, a TemnosponpyLous AMPHIBIAN From SourH AFRICA. By D. M.S. Watson, M.Sc., Lecturer in Vertebrate Palzeontology in University College, London. MECROPHOLIS Stowi was described by Huxley in 1859 from a small and very incompletely preserved skull found by G. W. Stow at Rhenosterberg (north-west of New Bethesda), District Graaf Reinet, Cape Colony. Subsequently R. Owen described another specimen as Petrophryne granulata. In his description he suggested that it might prove to be identical with Huxley’s type. The British Museum now contains these two type-specimens and three other examples of the form, all except Huxley’s type being from the Procolophon zone of Donnybrook, Upper Zwartkei, District Queenstown. Owen’s excellent description and beautiful figures have already made clear the general structure of the roof of the skull, but it is now possible to make out some more sutures, all of which are represented in Fig. 1. The most remarkable features are— 1. The small bone between the premaxille. ‘This is a small bone with the same ornament of tubercles as the other skull bones, lying rather loosely in a small fenestra left between the internasal processes of the premaxille. The fenestra is present in the three specimens which show this region, and in one small skull it is not filled with a bone. I can find no exact parallel for this bone, but in two types, Sclerocephalus Roemert (H. v. Meyer) and a small Stegocephalan, 1 Dr. G. R. Wieland, who kindly read the MS. of this paper, has furnished the following interesting memorandum: Indeed, it is curiously in accord with _ the foregoing facts that in the Paleozoic the thin rind of bark not only tended to outlast the wood in various types, but in turn sometimes aided in the conservation of lesser stems subsequently floated into the bark cavity. In the Laggan Bay bark cylinder figured by Seward no less than five of these floated-in Lepidodendron stems appear in fair conservation, while the fact that the cuticular layer must have been remarkably resistant is fully attested by the well-known occurrence in the Permian of Tonea of the thin bands of “‘ paper coal’’, made up as shown by Weiller of the little-changed and readily stained * cuticles of Bothrodendron. 4 / an Amphibian from South Africa. 341 (ct. Ricnodon), (B.M.N.H. R. 2818) from the Permian Gas Coal of Nyran, Bohemia, there is a small median element in the roof of the skull between the nasals and frontals. I propose to call the anterior of these bones, that which occurs in Jicropholis, the internasal and the other the interfrontal. Their occurrence is interesting in connection with the median bones so commonly found in the skulls of Dipnoans, which are remotely allied to the Tetrapods. 2. There is a distinct septomaxillare shown on each side in two specimens. It is a little curved plate of bone lying inside the nostril and articulating by its outer edge with the lachrymal. This bone has only once been recorded before in a Stegocephalian, in Eryops by Case; it also occurs in ‘ Bothriceps’ Husleyr. 3. The arrangement of the bones round the orbit is extremely unusual. The lachrymal is a large bone entering into the borders of the orbit and nostril; this condition, which obtains in many primitive reptiles, is very rare in Stegocephalia. Four of the skulls show very Fic. 1. Micropholis Stowi, Hux. Dorsal surface of anterior part of skeleton. x 1. Skull with all sutures on upper surface from R. 510. Vertebre, ribs, shoulder-girdle, humeri from R. 510a. Forearm and hand and quadrate from specimens in the Geological Society’s Collection. Hr. frontal ; I.Tem. intertemporal; Ju. jugal; Lac. lachrymal; Ma. maxilla; Na. nasal; P.Mz. premaxilla; P.O. post-orbital; P.Par. post-parietal; Par. parietal; Po.Fr. post-frontal ; Qu. quadrate; Qu.J. quadrato-jugal ; S.Mzx. septo- maxilla; Sq. squamosal; Tab. tabular. clearly the course of the ductus naso-lachrymalis (Text-fig. 2), which is a narrow canal running in the substance of the lachrymal bone from the orbit, which it leaves by two openings, to the nostril, where it opens below and behind the septomaxilla. This is, I believe, the first recognition of a ductus naso-lachrymalis in the Stegocephalia,- and the occurrence is very interesting from several points of view— (a) The very superficial position of the duct. In development in - recent types this begins merely as an epidermal thickening which grows down into the head and subsequently acquires a lumen; in 342 D. M. 8. Watson—On Micropholis Stowi, Hualey, Micropholis we have an early condition where the duct is still in the skin and has not yet sunk at all deeply. (6) The very great forward extension of the duct and its very unusual exit, practically on the outer surface and just behind the septomaxilla, are of interest. The duct only occurs in Tetrapoda, never in fish, and its origin is obscure; it may be suggested that it is possible that it has been derived from one of the lateral line canals so commonly found in Stegocephalia, of which there is no trace in Micropholis. The jugal is very small; it lies along the upper edge of the maxilla, and its anterior end is united by a suture to the lachrymal. Its slender posterior end just meets the anterior end of the post-orbital in the middle of the lower border of the orbit, the two bones being covered outside by the maxilla. The post-orbital is a very large bone forming a great deal of the posterior and lower borders of the orbit, having a very extensive suture with the maxilla and also touching the jugal and quadrato-jugal. _4. In the temporal region the three bones squamosal, intertemporal, and supratemporal are present. The squamosal has its usual relations, the sub-otic part of the bone sheathing the back of the quadrate and meeting the pterygoid. The other two bones are not in relation to any underlying bones and are remarkable in that the posterior bone, the supratemporal, is much reduced, covering a very small area EMx Mix. Fig. 2. Micropholis Stowi. Side of face. Xx 2. From a Geological Society specimen. The dotted lines in the lachrymal mark the course of the ductus naso-lachrymalis. between the squamosal, intertemporal, and tabular. In every other Stegocephalian that I remember the intertemporal is the bone which is reduced, the supratemporal remaining large. The palate (Text-fig. 3) is beautifully shown in Owen’s type- specimen. The basi-occipital has not been seen, but R. 510a shows well the two large exoccipital condyles, from above and the back. The basisphenoid is not well shown, but has large laterally directed basipterygoid processes with which the pterygoids articulate. There is a large parasphenoid forming a plate much higher than wide, whose upper edge is channelled to receive the cartilaginous mesethmoid. ‘lhe lower surface of the parasphenoid bears a double row of small backwardly directed sharp teeth. — The pterygoid articulates loosely with the basipterygoid process of the basisphenoid, sends a ramus, which consists of a deep narrow an Amphibian from South Africa. 343 plate whose upper border nearly touches the roof of the skull, back to cover the inner side of the quadrate, and to articulate with the squamosal. The rest of the bone appears in the palate, and its lateral border has a suture with the palatine. There is apparently no transpalatine. The palatine is an extremely narrow slip of bone lying between the maxilla and the very large interpterygoid vacuity. It apparently bears three rather large teeth. Its inner border is in contact with the pterygoid behind and the prevomer in front, and its anterior border forms the back of the posterior naris. The prevomers are large bones meeting one another in the middle line, articulating in front with the premaxille and forming the inner borders of the posterior nares, each of which is enclosed by a row of teeth. All the individuals have the lower jaw present and tightly closed on the skull. The jaw is very slender, and the thin bones of which NS Fic. 3. Micropholis Stowi, Hux. Ventral surface of anterior part of skeleton, x 1. Skull from R. 510. Lower jaw from all material. Shoulder-girdle and vertebre from a specimen in the Geological Society’s Collection. Ang. angular; Cr. coronoid; Den. dentary ;. P.Art. prearticular; P.v. prevomer ; Pa.S. parasphenoid; Pal. palatine; Pt. pterygoid; Sp. splenial ; Swr.Ang. surangular. it is composed have long overlaps: in development the ends of these bones are almost always pulled off with the matrix, but owing to the abundance of material it is possible to be quite certain of the structure. ; The articular is well ossified, but not produced behind the articulation. Its inner side is covered by the prearticular, which extends forward below the supra-Meckelian vacuity on the inner side of the jaw for nearly half its length. In front its upper end rests against the dentary. The hinder end of the prearticular is pierced by a small foramen for the chorda tympani (seventh nerve). The outer 344 D. M. 8. Watson—On Micropholis Stowi, Hualey, side of the articular is covered by the surangular, which reaches so low down that it very nearly, if not quite, touches the prearticular. The angular is a boat-shaped bone forming the lower surface of the jaw and overlapping the surangular and prearticular. The dentary is a long bone extending from the symphysis far back, overlapping the surangular and angular, and towards the front forming the lower edge of the jaw. The coronoid is a very large bone on the inner side of the jaw, reaching well forward and running back with a long overlap on to the angular and prearticular; in all regions it comes right down to the lower edge of the jaw. The splenial is a small bone on the inner side of the jaw, which has a symphysis with its fellow, and passes backward, overlapping the coronoid. The material does not show whether an epicoronoid was present or not, but if present it must have been small. Vertebral column. R.510a has fourteen vertebre in a continuous chain behind the skull, which are exposed from the dorsal surface. Another specimen shows the ventral surface. The atlas is shown in R. 510a. The neural arch is in two pieces which meet or nearly meet in the middle line. They are large and carry the facets for the exoccipital condyles. Behind and below is a small pleurocentrum, Fie. 4. Left scapulo-coracoid of Micropholis. x 14. Geological Society specimen. which articulates also with the neural arch of the second vertebra. The specimen cannot be cleaned sufficiently to show the intercentra in this region. All the succeeding vertebre are much alike; they are tripartite rachitomous vertebre of very slender build. The neural spines are of medium height and the zygapophyses slender and narrow from side to side. The anterior vertebre have a strong transverse process carried on the pedicel; in succeeding vertebre this becomes progressively shorter. The pleurocentra are very thin plates of bone of which little can be said, and the intercentra are small wedge - shaped pieces of a cylinder bearing a special projection for the articulation of the rib. The ribs are sufficiently described by Figs. 1 and 38, the more posterior ribs being similar but more slender. The shoulder-girdle is very well shown in a specimen formerly belonging to the Geological Society. The cartilage bones of each side are fused into one mass in which the sutures shown dotted in Fig. 3 are only very doubtfully recognizable. an Amphibian from South Africa. 345 The scapula has a large thin blade quite smooth on the outer surface, and, if the sutures are correctly recognized, is turned inwards in front so as to form a horizontally placed sheet of bone on the ventral surface, which is continuous with the coracoid and precoracoid, which are wholly on the ventral surface of the animal. ‘The scapula above the glenoid cavity is strengthened by the development of a strong buttress on its inner side near the posterior margin of the blade. This results in the formation of two deep pockets on the inner and posterior sides of the bone which are connected by the supra- glenoid foramen. ‘There is also a ‘coracoid’ foramen in the suture between the scapula and the precoracoid. There is apparently no glenoid foramen. It is perhaps of interest that a glenoid foramen occurs in the majority of frogs, where I have observed it in the genera Discoglossus, Alytes, Bufo, Megalophrys, Scaphiopus, Nototrema, Phyllomedusa, Hyla, Limnodynastes, Calyptocephalus, Leptodactylus, Ceratobatrachus, Rana, Breviceps, Callulops, Rhombophryne, Callula, and Cacopus; it does not occur in Pipa, Hymenochirus, and Xenopus. The interclavicle is a thin rounded plate of bone with no stem, and the clavicles are very slender, bent at right angles, and like the interclavicle scarcely at all ornamented. The cleithrum is not fully Fic. 5. Skull of ? Ricnodon, R. 2818. x1. To show the interfrontal and the small dermal ossifications in the orbit. exposed, but is, so far as seen, a very slender slip of bone lying along the front of the scapula; it seems to be certain that it was not continued up so as to form a cap over this bone, as in such types as Eryops and Cacops. The humerus is a very remarkable bone; it has only slightly expanded ends, whose broad planes are at right angles to one another, and the deltoid crest is both slender and short. The radius and ulna are sufficiently described by the figures (Figs. 1,3). The carpus is well ossified even in the young individual in which it is preserved, and the metacarpals and phalanges are little hour-glass shaped bones. Dermal armour. No specimen, except Huxley’s type, shows any of the scutes in position, but it is probable that the whole of the skin between the lower jaw and the clavicles was strengthened by a mosaic of small polygonal scales. I have seen no dermal ossifications behind the shoulder-girdle on either the dorsal or ventral surface. One specimen shows a series of ‘sclerotic’ plates in the orbits; these are not well preserved, but seem to be restricted to the upper 346 Dr. M. Remes—On Psalidocrinus strambergensis. part of that opening and to have united by their edges to the upper border formed by the pre- and post-frontals and frontal. Comparison with the very similar series of bones in the orbit of the specimen of ? Rienodon (Fig. 5) shows that these bones are not really in the eye at all, but are dermal ossifications in the eyelid corresponding roughly to the palpebral bones of crocodiles. Micropholis Stowi comes from the Procolophon beds, the age of which, although not accurately known, is undoubtedly either Lower or Middle Trias. It is hence of much interest as the latest rachitomous Stegocephalian, of which much is known (isolated vertebree were described many years ago by v. Meyer from the Lettenkohle of Wurttemburg). It is an exceedingly advanced type, as is shown by the following features :— 1. The unique arrangement of the bones of the top of the skull. 2. The enormous interpterygoid vacuities. I showed recently that the really primitive Amphibia (Péeroplax, etc.) have very small interpterygoid vacuities, and tha‘ enlargement of them is one of the chief lines along which the cliaracteristic Amphibian as opposed to reptilian evolution takes place They are larger in Micropholis than in any other rachitomoy*+2.te, but, as in all members of that order, the pterygoids are at .culated with the basisphenoid and not suturally united with the parasphen vid as in all Stereospondylus types. 3. The slender clavicles and great reduction of the cleithra, a parallel specialization to that common to the Reptilia. 4. The very slender humerus. 5. The loss of the grooves for lateral line sense organs. Despite its many advanced characters, Wcropholis is a comparatively unspecialized animal, free from the many bizarre features of such types as Zrematops, Cacops, and Jssorophus. Its ancestors are unknown, and no types really closely allied to it have been found, so that it will have to form a separate and distinct family. Il].—Psatmocrinus: 4 NEW GENUS OF CRINOIDEA FROM THE TITHONIAN oF SrkAMBERG. By Dr. MAurIc REMES, Olomouc, Moravia, and Dr. F. A. BATHER, F.R.S., British Museum (Nat: Hist.). PAPERS REFERRED TO. ie 1891. JAEKEL, O. ‘‘ Ueber Holopocriniden, otc.’’: Zeitschr. Deutsch. geol. Gesell., vol. xliii, pp. 557-670, pls. xxiv—xliii. 1907. JAEKEL, O. ‘‘ Ueber die Kérperform der Holopocriniten’’: N. Jahrb. f. Mineral., Festband, pp. 272-309. 1912. ReEMES, M. ‘‘Nové zpravy o lilijicich z moravského tithonu’’: Zvlastni otisk z Gasopisu moravského musea zemského. Brno1912. Roénik xii, Cis. 1, pp. 157-169, pls. i-iii. PART I. By Dr. M. REMES. HE species Hugeniacrinites strambergensis was-described by me in 1912 (pp. 161, 167, pl. iii, fig. 2) on the evidence of a single specimen (A), Examination of a better specimen (B), subsequently acquired, and believed to be of the same species, has convinced me that, though the species appears to belong to the family Eugenia- crinide, Zittel, still it belongs to none of the known genera. This Dr. M. Remes—On Psalidocrinus strambergensis. 347 new genus, it is true, resembles Aps¢docrinus in the union of its interradial processes, which form a kind of vault above the patinal cavity (Jaekel, 1907, p. 304; Remes, 1912, pp. 163, 168), but it differs from that genus in the form of the interradial processes, and especially in the size and shape of the radial facets. Description of the Specimens.—(A) Holotype of Hugeniacrinites strambergensis (Text-figs. 6-8). The measurements of the patina are: height, circa 8mm. [incomplete]; diameter at base, circa 5mm. ; diameter at upper margin, cerca 12mm. In the lower half the sides of the patina ascend almost vertically, but spread outwards rapidly in the upper half, till the level of the radial facets is reached. The interradial processes, of which two are partially preserved in this specimen, then ascend almost vertically, but with a slight inward bend, for a short distance. Their broken surfaces then bend rather sharply towards the oral pole, at the same time spreading out above the radial facets and then ending in a point, so that the outline of the whole cross-section somewhat resembles that of a spade in playing-cards (Text-fig. 6). The radial facets (Text-figs. 7, 8) are large and wide, with deep muscle-fosse. In the upper part of the patina, wherever preserved, theentéerradial sutures are distinctly depressed. The patinal cavity is spau is. It was the resemblance of the patina and of the radial facets to those of Hugeniacrimites which caused me formerly to refer the specimen to that genus, and to compare it with #. armatus, Zittel, and LZ. alpinus, Ooster. (B) Second specimen (Text-figs. 1-5). This also is a patina, and has the following measurements: height, from stem-facet to summit of interradial processes, 17 mm.; diameter at stem-facet, 4:8 mm. ; diameter at level of radial facets, 16-4mm. In external form this specimen resembles the holotype, except that the interradial processes are better preserved, one of them being almost complete. From this one we may infer that they were large and wide at their proximal “ends, but thinner above. About the middle of their height they spread out on each side into a wing-like process. The interradial sutures are distinctly and deeply depressed, starting from about half-way up the patina. Radial facets (Text-figs. 3, 4) large, deeply notched; they stretch almost half-way up the interradial processes. On them may be observed a ligament surface, ligament fossa, axial canal, and the transversely elongate muscle-fosse and articular fosse. — ‘In both specimens the external surface of the patina is smooth, with no distinct trace of any sculpture. Diagnosis of Psalidocrinus (yradis, Wadc6os, a vaulted chamber; the name marks the resemblance to Indicating direction of dip of Cretaceous rocks as seen on the coast. 1. Exposures of recent Raised Beach. 2. Remains of reptiles and fishes, usually associated with Entomostraca and mollusean shells. 3. Quarry with numerous reptilian remains and fish-scales. _ 4. At Setubal Point teeth of crocodiles are numerous, with small teeth and scales of fishes, and Paludina. 5. In the shales, limestones, and conglomerates between Escada and Plata- forma numerous remains of reptiles (Crocodilia, Dinosauria, and Plesiosauria) and fishes (Mawsonia, Lepidotus, Belonostomus, Diplomystus, Chiromystus, Acrodus), with numerous molluscan shells and badly preserved Entomostraca. 6. In a high cliff a rich bone-bed with well-preserved fish-remains. 7. In the shales and limestones between Pedra Furada and Montserrat numerous remains of reptiles and fishes associated with molluscan shells and Entomostraca. A Pterosaurian tooth found here. Remains of reptiles and fishes also in the conglomerate at Montserrat. 8. In an inlet at km. 4, shale with Entomostraca and fish-remains (Mega- lurus, etc.) was met with. VI.—More azsour SEPTARIAN STRUCTURE. By J. HE. Topp, M.A., Assistant Professor of Geology and Mineralogy, University of Kansas. N his article on septarian structure in the March number of the GxotocicaL’ MacazinE Dr. A. Morley Davies seems to call for further light upon the subject, hence the following is offered. The writer became convinced of the fallacy of the current teaching concerning the formation of concretions with cracked interiors and of septaria more than thirty years ago, and has so taught in his classes ever since. In 1902 he published a paper on ‘‘ Concretions and their Geological Effects”, which presented facts which virtually demonstrate that the cracking is due to the expansion of the exterior rather than by a contraction of the interior, as Dr. Davies has also concluded. The clearest evidence was obtained from compound concretions in the loess of Eastern Nebraska, of which illustrations are given.: Simple concretions abound there, and uniformly whenever they are over an inch or two in diameter they are cracked inside. From them there is little instruction on the point under discussion except that the interior is of the same composition as the exterior, viz. fine silt cemented with carbonate of lime. There is not more of clay in the 1 Bull. Geol. Soc. Am., vol. xiv, pp. 353 ff. 362 J. E. Todd—On Septarian structure. Fias. la-e. A series of drawings illustrating the growth of a concretion having cracked interior, caused by the expansion of the exterior by more rapid interstitial deposition in that portion. Fic. 2. Diagram of a compound calcareous concretion from the Loess of Eastern Nebraska. The different members were doubtless added in the order indicated (a-d). FIGs. 3a-c. Photographs of fragment of such a concretion. J. H. Todd—On Septarian structure. ~ 363 cracked portion, as the old theory postulated. The compound ones, on the contrary, are very instructive. They show apparently successive additions made on one side after another and sometimes one overlapping another, as in Figs. 2 and 38. To explain them by shrinking we must assume that small bodies of very contractile -material had been mixed with less contractile in curious lenticular shapes by some inexplicable process. And if that be admitted, the cracks should be widest in the centres of the respective contractile members, whereas the facts are that the widest part of each crack is toward the centre of the whole. And the centre of the concave or inner side of each addition is evidently lifted away from the one under it. By a further study of Figs. 2 and 3 it will appear very clearly that the most obvious and easy explanation is that there is first a collection of molecules of calcium carbonate in the pores of the silt around some nucleus, but the conditions are such that the deposition is not entirely at the surface, but largely in a shell reaching to a considerable distance below the surface. After the concretion has attained a certain size the centre will cease to receive additions to its mass, while the outer shell will continue growing both radially and tangentially, with forcé not only sufficient to crowd back surrounding and superincumbent material, but to also rend asunder the interior. _ Should this seem incredible, let us remember the power of molecular attraction manifest in the tensile strength of wire, or in the supporting strength of rock, or of steel. In all cases it is the attraction of molecule for molecule, the apparently opposite directions in which it is manifested being due to different mechanical relations. The power of freezing water and the capillary action of water in wood which was used by the ancients for splitting rock are also illustrations of similar forces. It may be noted further that the first cracking of the interior takes place when the thickness of the growing shell is several times the diameter of the ruptured interior, and that the cracks spread gradually toward the surface which they may eventually reach. When that is attained, water charged with various minerals will enter and begin filling the crevice. When lined with crystals they constitute a form of geode; when perfectly filled with crystalline matter, a true septarian. Professor N.S. Shaler appealed to similar action in the formation of geodes of the common form, and also ascribed the filling of many veins to the expanding effect of crystallizing minerals.' Dr. Davies argues in his paper that we should not hope to find effects of the expansion of the concretions in the surrounding shale because the compression of the shale was subsequent to the growth of the concretion. That may be true in some cases, but the writer has frequently noted in the shaly clays of the Pierre formation in South Dakota a shell of cone-in-cone structure surrounding large concretions of the sort under discussion. He has considered this a direct effect of the growth of the concretions. 1 “Formation of Dikes and Veins’’: Bull. Geol. Soc. Am., vol. x, pp. 253 ff. 364 G. F. Monckton—Human Skeleton, B. Columbia. This expansive power of crystallizing or solidifying minerals may be credited also with the formation of those problematic structures known as ‘stylolites’ or ‘ lignilites’. Given a horizontal film of some impervious substance in a mass of calcareous mud, hard particles above or below it to serve as nuclei for the deposition of calcareous material from one side only, and we should expect that this force of expansion in solidification would force a nucleus below the film upward and one above the film downward, simulating exactly what we find in ‘ stylolites’. In closing, the writer would allude to another observation which seems to point in the same direction. He has often received drillings from artesian wells. When they have been put wet into glass bottles he has frequently found some of the bottles broken in drying. So far as tests were made, all those broken were found to contain matter highly calcareous, while those unbroken were sand or clay without calcareous material. VII.—Gerotocgicat Norges on a Human SKELETON FOUND IN SILT ar Savonas, British CoLumsBia. By GEOFFREY F. MONCKTON. a the early part of 1910 I noticed some bones projecting from a cliff near the foot of Kamloops Lake, B.C. The cliff is composed of silt, and belongs to the formation known as the White Silts. These belong to the Quaternary period, having been laid down during the retreat of the great glacier. They stand in very steep banks, which is partly due to the small rainfall, only 7 inches, in this district. Little streams of water from melting snow, collecting in a hollow on the flat behind, had been for three years or so gradually cutting a fissure, and it was in the side of this fissure that these bones appeared. Some cutting down of the face of the cliff to bank up the trail exposed them more, and at the end of the year a road was made up it and we took them out. The silt is very definitely laminated. ‘There are also a few seams of fine pebbles through it. One of these actually touched the bones. None of these seams or laminations showed any sign of movement of the ground. Had the bones been put in from the top it would have necessitated a hole 12 feet deep. A fissure would Have left its mark on the seams of pebbles. People have been living along the beach in front of the cliff since 1860, and at that time the face of the cliff must have been at least 8 feet farther forward, as it has not only been constantly cut back from time to time in order to bank up the trail, but a good deal was taken away in the early eighties to level sites for houses. The bones must therefore be of the same age as the silt. The silt is very dry, and contains a small quantity of lime. It should therefore be a good preservative medium. As to its position, the bones of the body were all bunched together, the legs stretched forward, and the skull close to the knee, as if the body had rested in the soft mud in a sitting position, and, as it decayed, the bones had fallen together. I should imagine that its owner was drowned very likely by falling through thin ice. There G. F. Monckton—Human Skeleton, B. Columbia. 365 were no implements whatever found with the skeleton. Unfor- tunately the lower jaw is missing, but most of the other parts of the skeleton were found. A careful search revealed no teeth. During the following summer the Canadian Northern Railway laid a track across the spot in my absence. I submitted this skeleton to Mr. Charles Hill Tout, who is well known for his ethnological work in connection with the British Association and who has made a special study of prehistoric man in British Columbia, and I quote from him as follows: ‘It was the skull of a mature person. All the sutures had coalesced. The type is also markedly dolichocephalic, the cephalic index being about seventy-five. In stature the individual was short, not much over 5 feet, and the ridges on the tibia or shin-bones are less sharp than those of modern man.’ The bones are now in the hands of the specialist attached to the Canadian Geological Survey for examination. The exact point of discovery was about three hundred yards above the Thompson River Bridge, at the foot at Kamloops Lake, on the north side. It is about a mile from Savone station on the C.P. Railway. o HfE 30 60 ————————S$?sT{T_ 4 Boulders | from » Mountairy j Sits with horizontal adie bedding an layers of broken rock near | A O sae mountain 1% Or, Zs Section showing position of skeleton in silts at Savonas, British Columbia. Briefly, the later geological history of this district is as follows. During the Glacial period, the elevation was much greater than it is now. At the end of that period, the land gradually subsided as the ice receded. Dr. G. M. Dawson seems to think that it subsided to a depth of 4,000 feet below the present level, but I venture to differ as to that, and consider that 1,000 feet would be quite sufficient. After that it was again uplifted to its present position. Many large glaciers still remain in the country, and anyone who has travelled much in the higher mountains will realize that a greater snowfall or uplifting of the land would cause a great extension of the glaciers. A very complete description of the White Silts is given by Dr. G. M. Dawson, who named them, in vol. vii of the Canadian Geological Survey Reports. From this I quote: ‘It is probable that we - may place the upper level of the Silt formation in this region at about 2,500 feet, though it is still apparent that the more important developments of the deposit lie below 1,700 feet. The Silt deposits are found in this part of the interior plateau down to € 366 G. F. Monckton—Human Skeleton, B. Columbia. less than 1,000 feet, but it is possible that some of the lower-level. deposits have been secondarily formed from the denudation of the higher. “In the valley of the South Thompson the Silt formation is most characteristically represented, forming, as before stated, broad terraces or benches along the sides of the valley, with the surfaces gently sloping towards its axis, where the river has formed for itself a deep subsidiary channel. In some places, as above Kamloops on the south side of the valley, the edge of the White Silt bench has been cut up by little streams descending at times from its summit into complicated and ragged ridges. The eroded faces are always very steep and occasionally vertical, and in the sunlight have a peculiar glossy shimmer due to the great abundance of particles of mica, which when the bank is wet become arranged parallel to its surfaces, and on drying adhere in that position. The bedding is generally almost or quite horizontal, and layers of a few inches in thickness succeed one another with great regularity. The deposit is remarkably fine throughout, and no boulders or stones so large as to imply the action of ice were seen. ‘‘These White Silts very often rest directly upon the boulder-clay. They are generally fine and uniform in texture and are usually well bedded in perfectly horizontal layers of 1 to 2 or 3 inches in thick- ness. Where occasional sandy or gravelly layers are intercalated these are attributable to local causes, being most frequently found opposite the mouths of valleys down which streams have flowed. The silts have evidently been laid down as a rule in tranquil water of considerable depth, and their material has as obviously been supplied by streams or rivers discharging from glaciers not far removed.” From the general correspondence in elevation between this and other deposits in the Cordilleran region and the Red River Valley he draws the conclusion that the inland lake in which these silts were formed was connected with the sea, and ‘‘ governed in its level by that which the sea held at the time”. It does not appear to me that this was so. If it had been, one would expect to find beaches with marine deposits on the coast at much higher levels than that at which they have been found, which does not exceed 200 feet. I think we may find sufficient reason for the formation of a large inland lake which would include the valley of the North Thompson for 100 miles north of Kamloops, and the South Thompson Valley from a short distance below the Little Shuswap Lake to below Spences Bridge, about 125 miles more, with some tributary valleys. This reason is the narrowing of the outlets through high mountain ranges which would result in the blocking of the channel by the meeting of glaciers from the two sides. As to the outlet leading to the Fraser, at Gladwin the 4,000 ft. contour-lines on opposite sides of the Thompson are only 2} miles apart, and at the 3,000 ft. 14 miles. Sixteen miles further up the river, near Spences Bridge, the difference is barely 2 miles at the 3,000 ft. level, and less than — 3 miles at Pukaist, which is 8 miles higher up. At the 2,500 ft. level - they are a mile and a half apart at the first two points and scarcely G. F,. Monckton—Human Skeleton, B. Columbia. 367 over 2 miles at Pukaist. From Spences Bridge to below Gladwin many summits of 5,000 feet and over occur within a mile of the 3,000 ft. level, so that no great stretch of imagination is required to block this outlet with glaciers from the heights above up to the 2,500 ft. level long after théy had retired from the more open part of the district. As the river cut down, it must also have been temporarily affected by serious slides in this gorge. Even since white men came to this country the river has been completely blocked on occasions by slides, and was once raised 70 feet. There is another outlet immediately south of Kamloops, where the distance between the two contours at 3,000 feet is 2 miles, and also one leading into it from the head of Cherry Creek, which is less than a mile, but this is above the 2,500 ft. line, and so is the narrower valley of Campbell Creek into which these lead. In this region also there are several high mountains from which local glaciers would descend till a late period. The main part of the water of this lake would therefore very likely have to find its way eastward by Little Shuswap Lake, whence it would pass through the Greater Shuswap Lake either through the very narrow Eagle Pass, 1,840 ft. elevation, into the Columbia, or in larger quantity into the Okanagen through a pass 1,196 feet above the sea. At several points on its course it would probably be ' greatly restricted by glaciers from the mountains close by. It would also be considerably impeded at certain seasons by icebergs breaking away from glaciers on the edge of the water, especially in the earlier stages of the recession and stranding of the ice in the channel. These outlets that I] have mentioned would have to carry away the water from a district covering about 12,000 miles, and probably the Little Shuswap would be the only one available. It is estimated that the ice covering this region was in many places 6,000 feet thick. Since its general direction was south-eastward, it must have been 5,500 feet thick at Kamloops Lake, as it had to cross a mountain range to the south, which averages over 4,000 feet above the sea. Kamloops Lake level is 1,110 feet elevation at low- and 1,138 at high-water mark. _ The time which has elapsed since burial of the skeleton I estimate as follows. I calculate that the silt and gravel which would be deposited in the area now occupied by Kamloops Lake and six miles west, and two miles east of it (comprising with its tributary valleys about 150 square miles), would be drawn from a region extending 35 miles north and 10 miles south, with a length of 25 miles. This would cover 1,125 miles, of which the probable average area covered by glaciers during the period of their retreat would be at least 500 square miles. The area to be filled may for purposes of the calculation be divided into a lower trough below 1,500 feet, a middle stage up to 2,000, and an upper level up to 2,500 feet above sea-level. The lowest would cover 50, the upper 150 square miles. Basing our calculation on the Muir Glacier discharge as measured by Professor G. F. Wright, of one-third inch over the whole area covered by the glacier annually — 8368 G. F. Monckton—Human Skeleton, B. Columbia. One-third inch on 500 square miles would fill lower trough of Years. 50 square miles in 1,800 years, and from just below the 1,200 ft. level in : 1,100 One-third inch on 500 square ‘miles would fill the middle stage up to the top and provide sufficient for the eee Ma of silts in all the sheltered bays up to 2,500 feet in : - 7,200 Total number of years for Henositie of silts since burial of the skeleton : - . 8,300 In making this estimate we fee nee that the time would probably be much less: (1) because of frequent slides from the mountains, which would fill many places with local material; (2) because when the great glacier covered all this region and was travelling over high ridges it “would naturally tend to leave deposits of boulder- clay at several points in hollows, or in places where on account of the flattening of the grade it could not exert much pushing power, and as the glacier retreated these deposits would be very quickly reassorted by the flooding waters. It appears to me that for these reasons the above figures might well be reduced by 1,500 years. Without making such an allowance, there would have elapsed Years. since the burial of the skeleton . ; . 8,300 If we allow 2 feet in ten years as the average rate for the cutting down of the silts when the land began to rise from the 2,500 ft. level to the water-level in Kamloops Lake, the outlet would be reduced to 1,140 feet in less than 6,800 years (high-water mark is 1,138 feet) ; A ; . 6,800 Total number of years since burial A é : . 15,100 The rate of cutting down would probably be much greater: (a) because silt deposits above 2,000 feet would not be universally distributed ; (6) on account of the rush of water which would follow the removal ‘of dams in the narrow gorge to the west near Spences Bridge ; (¢) the uplifting of the land, say 1,000 feet ; (d) the lake has now cut down so low that the grade of the river below it is only 10 feet to the mile, and therefore its excavating power is very small now compared to what it must have been. I should make a further deduction of at least 1,500 feet for these reasons. The cutting down has not been carried on at an even rate, since it is evident from the appearance of terraces and old shorelines in the valley that the level of the water has at times been almost stationary and at others it has been lowered with a sudden rush, due probably to the breaking of dams and in some part to the elevation of the land. These two deductions would reduce the total to 12,100 years. There is also another possible reduction to be made. These calculations have been founded upon the theory that the whole lower trough of the valley was filled by the silts. There is an argument against this, which is, the peculiarity (referred to by Dr. G. M. Dawson in several papers) that the greater part of Kamloops Lake is evidently a rock basin, 400 to 600 feet deep. If it was once all filled with silts, how could it be excavated? If we assume, however, that the silts were simply deposited in limited areas, each area fed by its own river system, the explanation appears simple. We should then have the silts of the Deadman River extending westward from its mouth and G. F. Monckton—Human Skeleton, B. Columbia. 369 eastward about 3 miles up the lake, where the water is shallow, except where there is a current which must have been stronger in the past. There would be found further up the Deadman where the stream was more rapid a development of gravel, which is the case, and as the river built up its delta and the glaciers receded, the silts would be laid down farther back on a higher level, as may be seen now near Criss Creek. There would be a small local development of silts at the mouth of Copper Creek at points where there would be but little current, and a large area at the mouth of the Cherry Creek valley and also at the Tranquille River, where there are actually large exposures of the silts at the mouth and contemporaneous gravels higher up (see Dawson’s Report, vol. vii, Geol. Survey, as to this last). If this theory be adopted, and it has always seemed to me the correct one, it would explain why some 10 miles of this lake average over 400 feet below the present outlet, which outlet itself is not more than 20 feet above bed-rock showing now in the river below. The only other possible explanation of this hole it that it was excavated by ice, but if so, why did the ice leave the silts untouched at the lower end of the lake ? and there is no trace of such ice. Shuswap Lake to the. eastward has the same peculiarity, namely, a rock basin with deltas of silt and gravel close to it, showing no silt along its sides except where it might be locally derived. Should this surmise be correct, another 3,000 years might well be taken off the 12,100, leaving only 9,100 years. To my estimates it will no doubt be objected that they are based on too high estimates of glacier work. It is true that researches such as those of Dolfus Ausset on the Unter Aar Glacier premise a much slower rate of glacial deposit and erosion, but against this there are several Aroumentc. The first is that his observations were drawn from glaciers descending from mountain peaks. Now, the fundamental reason for the existence of a mountain peak is that it is composed of the hardest material in the district. Therefore an- estimate of erosion based upon work done under such conditions is certain to be very low, much too low for calculation of the work done by an ice-sheet crossing all kinds of rock-formations. Then, again, to estimate the work of ice-sheets covering hundreds and thousands of square miles by that which is done by glaciers of such limited area is very deceptive. Therefore I put aside his calculation of 0°6 of a millimetre eroded yearly by the Unter Aar Glacier as useless for our purpose. ‘When we compare the movement of the little glaciers of the Alps with that of the great ones of Greenland we find that while those of Switzerland move at the rate of 3 feet daily, that of Jacobshavn Fiord, 24 miles wide, moves 60 feet a day according to Helland, and Rink estimated the movement of the Karajek Glacier, 4 miles wide, at 22 to 38 feet daily, and that of others at 24 and 46 feet daily, _ although he considered that the average motion of glaciers in Greenland was not over 21 feet. As to the amount of deposition, Helland reported a great variation in Greenland in the amount of glacial mud carried down in suspension by glacial rivers, ranging from 2,374 grammes per cubic metre of DECADE V.—VOL. X.—NO. VIII. 24 \ 370 Reviews—C. Reid—Submerged Forests. water at Alandgardlek and 678 at Tuaparsuit, down to 104 at Jacobshavn. J. KE. Marr (Gror. Mae., 1887) said that results in Greenland showed a variation from 200 grammes in one river to 9,744 in another. Great glaciers still exist in British Columbia and Alaska, but are receding rapidly. The Muir Glacier in Alaska when seen by Vancouver in 1794 filled the inlet 25 miles farther down than it does now. I may say that Vancouver’s statements and surveys were remarkably correct. The supposition that the recession of the glaciers in this area is comparatively recent is borne out by the fact that the surface disintegration as shown by excavations is practically nil. Also, we have some evidence of a rapid fall of the lake-level in old Indian kekwullie houses, which were pits roofed with logs and boughs and then covered with earth. At two points on Kamloops Lake similar huts exist about 70 feet above high water. They are always built as near to water as possible. One of these is at least two hundred yards above the level of the water. But about fifty years ago some were inhabited near the lake as low as 15 feet above high-water mark. There seem to be none between these two stages, suggesting a rapid fall in the water-level. Regarding my estimate of 10,100 years, I may also note that Warren Upham allows 5,000 years for the erosion of glacial drift and 5,000 years for the Champlain period, which includes the period of: retreat of the glaciers. My figures for this would be as above, 9,800. Professor Wright estimates 7,500 years for the streams tributary to Lake Erie to cut their valleys, a work which commenced after the retreat of the glaciers. Professor N. H. Winchell estimated 8,000 years for post-glacial erosion of the Mississippi gorge from Fort Snelling to St. Anthony Falls; G. K. Gilbert 7,000 years for the recession of Niagara Falls, which commenced soon after the close of the Glacial period. Against this must, however, be set the opinion of Dr. J. W. W. Spencer in his exhaustive report on the recession of the falls for the Geological Survey of Canada, in which he estimates 39,000 years as the period required, which he considers might be reduced 38,500 years by admitting Russell’s theory of the Erie discharge. If the suggestion advanced by Dr. Pohlmann to the effect that the river re-excavated an old channel from the whirlpool to Queenston were correct this might be further reduced. The writer is not competent to judge as to this, but the retreat of the glacier from the high ranges of the Western Cordillera would probably be much later than in the east. It is generally admitted that the glacial RHEVIEWS. Sats « J.—Susmercep Forests. By Crement Rep, F.R.S. 8vo; pp. viii, 129, with 1 plate and 4 text-illustrations. Cambridge: at the University Press, 19138. Price 1s. net. N this clearly and concisely written little book we are taught the | lessons that can be learnt from a careful study of submerged forests by a geologist who is the chief authority on the natural / Revie C. Reid—Submerged Forests. 371 history of the subject. The occurrence of peaty beds and of stumps of trees that had evidently grown on the area had been observed more than a century ago on the borders of estuaries and of other marshy tracts adjacent to the open sea, as in Lincolnshire. For the most part these exposures afforded no clue to the thickness and | character of the strata that are now known to compose the submerged forests, and it is chiefly from the fine sections opened up in excavations for docks that the great interest and importance of these accumulations have been made manifest. As the author points out, there is no doubt that some portions of marshy areas have subsided through compression and shrinkage of silty and peaty deposits. Again, in some instances alluvial areas that had been protected from the sea by higher portions of the mainland, as in north-western Norfolk, or by accumulations of beach or blown sand, as in the case of Eccles on the north-eastern coast of the county, have been brought within the influence of the sea by the erosion of the barriers or the shifting inland of the sand-dunes. The true submerged forests, however, are those which have undergone a considerable amount of depression, proved when the full thickness of the accumulations has been determined. Judging by the evidence of various excavations and borings, the term is rightly applied to nearly all the submerged forests observed along our coasts. Modern science requires that attention be bestowed not on the mass of the strata, but on each differing layer, so that the sequence of geological events, the fauna and flora, and the objects of archeological interest may be correctly recorded. The evidence supplied by dockyards and borings proves that some 50 or 60 feet of deposits may be grouped with the submerged forests, excluding the most recent marsh deposits and the uppermost, estuarine silt or warp known as Scrobicularia-clay. Deeper down there are found alternations of peat or peaty soil with roots of trees, and estuarine silt, at three or four successive horizons, the whole often based on estuarine sand and gravel. y The author rightly refers to older deposits of somewhat similar character, such as the Cromer forest-bed of Pliocene age and certain Pleistocene deposits, as at Clacton, to which, however, the term ‘submerged forests’ is by common usage not applied. In dealing with the submerged forests he givés particulars only of the principal localities where careful detailed evidence has been obtained, as along the Thames Valley at Tilbury. There the channel was cut to a depth of about 60 feet below the modern river-bed, and the maximum elevation of the land is estimated to have been about 80 feet above its present level. Further north, along the eastern coasts, it is noted that in Kast Norfolk and in the Fenland the ascertained depth of the Alluvial strata with peat-beds is 50 or 60 feet, and in the Humber the channel was about 60 feet deep, as in the case of the Thames. It is remarked that ‘‘ north of Flamborough Head it seems as though depression gave place to elevation, and when we pass into Scotland the Neolithic deposits seem to be raised beaches instead of submerged forests’’. Similar evidence is referred to in Scandinavia, Northern Ireland, and the Isle of Man. 372 Reviews—C. Reid—Submerged Forests. Reference is made to the Pleistocene accumulations of the Dogger Bank and to the recent observations of Messrs. H. Whitehead and H. H. Goodchild, who obtained from the Bank loose masses of peat, known to the fishermen as ‘moorlog’. Samples of this, examined by Mr. and Mrs. Reid, yielded a highly interesting series of plant- remains, and also of insects which were determined by Mr. G. C. Champion, all of species still living in Britain. The occurrence of this peat indicates a sunken land-surface or submerged forest at a depth below sea of about 60 feet or more. It is remarked that ‘‘the lowest submerged land-surface is found in Holland at just about the same depth as it occurs in England, and probably on the Dogger Bank also”. Further, it is suggested that on this Bank the Pleistocene deposits may have ‘‘ formed islands in the ancient fen, as they do now in East Anglia, Holderness, and Holland’. It should be noted that the Pleistocene fossils of the Dogger Bank have been known for a longer period than ‘‘the last 50 years’. In the GrotogicaL Magazine for 1878 (p. 443) a figure is given of the lower jaw of a mammoth dredged off the Dogger Bank in 1887. The evidence of the submerged forests of Lancashire and the Bristol Channel again points to subsidence of about 60 feet, while data obtained in the excavations at the Celtic village of lake-dwellings at Glastonbury are mentioned as indicating that the movement of subsidence ceased ‘‘ probably not more than 3,500 years ago”. Interesting particulars and conclusions are given respecting the English Channel and the submerged forests generally, in the south of England from Pegwell Bay to Cornwall. Some account is also given of the severance of Great Britain from the Continent. The areas were connected probably in Newer Pliocene times by a low divide, an extension of the Chalk of the North Downs. ‘‘ Afterwards, during the Glacial epoch, when an ice-sheet accumulated and blocked the northern outlet of the North Sea, the water was ponded back in the southern part. There was no easy outlet northward for the water of the Rhine and other great rivers, so the level of the North Sea rose slightly till it overflowed this low col and cut an outlet where les the present Strait of Dover.” Subsequent elevation obliterated the Strait, and ‘‘converted a great part of the North Sea into a wide alluvial plain’”’. When subsidence initiated the formation of the submerged forests the Strait again became an open channel, which has been gradually widened and deepened. The author points out that much submarine erosion has taken place: that ‘‘ tidal scour may go on at any depth, provided the current is confined to a narrow channel”’, and the Atlantic swell,may remove coarse sand at depths of at least 50 fathoms. In the English Channel the troughs coincide with lines of tidal scour, and do not usually continue the lines of existing valleys, while the continental platform ‘¢ig in all probability in the main a feature formed by the deposition of sediment during long ages ”’. In East Anglia the Norfolk Broads are regarded as directly associated with the subsidence connected with the submerged forests. In the south of England Romney Marsh and Pevensey Level are considered to be submerged flat-bottomed valleys that have been Reviews—Dr. W. Gibson—The Concealed Coal-field. 373 silted up. Westwards the marshlands bordering the rivers, as near Lewes, afford similar evidence, while Southampton Water, the Solent, and Spithead, with the adjacent harbours, are likewise submerged valleys. In Cornwall and on the Devon borders Plymouth Sound is held to represent a basin once filled with Tertiary and Secondary deposits and subsequently cleared out, the rocky basin having been in part silted up again. The stream-tin deposits belong to a late stage of the Pleistocene period, and were succeeded by the growth of trees and of sundry layers belonging to submerged forests. With regard to the vexed question of the isolation of St. Michael’s Mount, the author is of opinion that ‘‘as far as can be calculated from its known rate of encroachment, the sea cannot have reached the Mount till long after the Roman period ”’. In a final chapter the author gives a summary of his conclusions, and points out that his main object has been to suggest directions for further research on a much-neglected subject. All the accumulations of the submerged forests appear to be of Neolithic age. The fauna and flora consist of Jiving British species, with a few mammals since exterminated by man. The account which we have given of this volume will indicate how earefully the author has considered all aspects of his subject with regard to both fact and opinion. At the same time it may be said that opinions which will be regarded by some geologists as debatable, are not wanting. In a bibliography the author gives the titles of papers specially bearing on the matters discussed, but as he does not attempt to deal with or even enumerate the many submerged forests that have been described, there is no mention of some geologists like Pengelly, Ussher, and Codrington, who have published important papers on the subject. I].—Gronocicat Survey Memorr. THe ConceaLeD Coat-FIELD oF YoRKSHIRE AND NorrinéHAMSHIRE. By Watcor Grsson, D.Sc. 8vo; pp. vi, 122, with 3 plates and 5 text-illustrations. London: printed for His Majesty’s Stationery Office, 1913. Price ls. 6d. HIS is an eminently practical memoir, dealing as it does with the underground extension of the Nottinghamshire, Derbyshire, and Yorkshire Coal-fields, sometimes grouped as the Great Yorkshire Coal-field. The exposed areas of Coal-measures in Nottingham border the Erewash valley in the western part of the county ; in Derby they border the western side of that river-valley, extending through Chesterfield to the northern end of the county ; thence in Yorkshire the strata are exposed from Sheffield to Leeds. The Magnesian Limestone and other Permian beds cover the eastern portion of the Coal-measures, succeeded by various members of the Trias and sundry superficial deposits. Beneath the Permian and newer. deposits Coal-measures have been proved through the greater part of Nottinghamshire, and northwards into the area now known as the East Yorkshire Coal-field, which extends from Doncaster to Thorne and Selby in the Vale of York. This area is shown on the map 374 Reviews—Geology of Hampstead Heath. (plate i), on which the sites of collieries and boreholes are marked, with the depth to Coal-measures, and other information. It comprises about 1,200 square miles, and the author remarks, in regard to the accessibility of the coals, ‘that the boring at Kelham, near Newark- on-l'rent, indicates that the lower seams of the Middle Coal-measures (a division which contains the chief workable seams), ‘are well within the 4,000-ft. limit of working in Nottinghamshire. In south Yorkshire, from the evidence of the Thorne Boring, it is reasonable to infer that they will seldom exceed this depth, while the Top Hard Coal in Nottinghamshire and Barnsley seam in Yorkshire should be met with under 3,000 feet.” After a general description of the Carboniferous strata, including particulars of the Coal-measures with its coal-seams and fossiliferous horizons, the author passes on to the Permian, Triassic, and superficial deposits, and gives a tabular statement of the thicknesses of these newer formations as proved in various borings from Owthorpe to Selby. A series of vertical sections (plate 11) also illustrates this subject. There is an important chapter on the configuration, structure, and limits of the coal-basin, and the map before mentioned will be found of great use in the study of this part of the subject. On it the contours of the concealed surface of the Coal-measures are indicated, and the approximate depth to these strata, over areas not yet proved, can be ascertained. Diagrammatic sections are also inserted in the text to explain the probable structure of the coal-field. Detailed records of shafts and borings are given, together with a series of vertical sections (plate 111) to “illustrate the Middle Coal- measures above the Top Hard or Barnsley Coal. The volume thus contains a full account of all that is known of this great and important tract of concealed Coal-measures, the details being tabulated and the problems discussed by one who is a leading authority on the subject. I]J.—Hampsreap HeatH: irs Grotocgy anp Narurat History. Prepared under the auspices of the Hampstead Scientific Society. 8vo; pp. 328, with coloured frontispiece, 10 other plates, and 3 maps. London: T. Fisher Unwin, 1913. Price 10s. 6d. net. M\HIS volume, printed in bold and excellent type on thick but light paper, will justly take a high place among local natural histories, and, as the several contributors show, ‘‘ Hampstead still offers, considering its nearness to London, considerable scope for the study of nature.’’ This especially applies to the protected area of the Ken Wood Estate. Of the three maps, one shows the contours of the land, without names of places. Affixed in front of it is a geological sketch-map on transparent paper, showing somewhat roughly the names of principal localities, and the areas occupied by London Clay, Bagshot Sand, Plateau Gravel, Boulder-clay, and Valley Drift. In this map - is marked the area under description, which is confined to a radius of 3 miles from the Hampstead Flagstaff. The third map shows the northern portion of Hampstead and part of Finchley, but does not extend over the 3 mile limit. Reviews—F. P. Mennell’s Manual of Petrology. 375 The section on geology occupies twenty-eight pages, and when we mention that it is written by Mr. F. W. Rudler it is needless to add that it is an admirable essay. An account is given of all the formations above mentioned, including even the ‘ Claygate Beds’, a term recently applied to the passage-beds of sand and loam that bridge over the interval between the mass of stiff London Clay and the mass of overlying Bagshot Sands. Two photographic views are given of the Sands in Ken Wood. The fossils of the London Clay rightly receive a good deal of attention, and a new list is given of species collected from the Hampstead Tube Railway. The minerals of the formations are duly noted, while the subjects of soils, scenery, - water-supply, and deep borings are not neglected ; nor, we may add, are references to the former resident geologists, N. T. Wetherell and Caleb Evans, and to others who have dealt with the geology of the district. The section on topography is by Messrs. H. R. Maynard and C. J. B. Findon, while one of the three botanical chapters, that on the vegetation of Hampstead Heath and the neighbouring woods, by Mr. A. G. Tansley, contains references to the soils and substrata, the author observing that ‘‘it is essential to understand the geological structure of a district in any attempt to unravel the distribution of the vegetation ’’. In other chapters there are records and descriptions of various forms of animal life, also of pond life in particular, and of climate. IV.—A Manvat or Perrotoey. By F. P. Mennerz, F.G-S., ete 8vo; pp. 256, with 124 figures in the text. London: Chapman and Hall, Limited. Price 7s. 6d. net. fYVHIS book forms an enlarged and improved edition of the author’s Introduction to Petrology, which was published in 1909. The text has been printed in larger type, and over fifty of the figures, mostly photomicrographs, are new and are a great improvement on those which appeared in the book in its earlier form. The chapters have been re-arranged in more logical sequence, several of them have been rewritten, and tables of analyses have been inserted. The first three chapters deal with the general and optical properties of rock-forming minerals. Due emphasis is laid on the value of interference figures as aids to the determination of minerals in thin sections. For purposes of description the minerals are classified according to their chemical compositions, instead of by their optical properties. Had they been arranged according to the latter this part of the book would have been more immediately “useful in determinative work. ‘The insertion of the actual values of the birefringence for the doubly refracting minerals would have been a great improvement. The simplification of the chemical formule for one or two of the minerals has been carried too far. Thus topaz is given as Al, O, . $103, thereby failing to show the importance of the hydroxyl and fluorine in its constitution. The descriptions of the igneous rocks occupy four chapters and though necessarily short they are very much to the point. The nomenclature has been reduced to the simplest form. The rocks are 376 Reviews—A. Holmes—A ge of the Earth. classified according to their acidity and mode of formation, whereby nineteen divisions are obtained, and the names of these divisions, with suitable prefixes, are made to suffice. ‘The book is written to meet the needs not so much of students as of working geologists, and for such simplicity of nomenclature is a great advantage. Nevertheless, it is very difficult to place many important types in so simple a scheme; thus, borolanite and kentallenite are found under the dolerites, while such well-known groups as the essexites and monzonites do not appear. There are short chapters on the sedimentary rocks, weathering, the chemistry of rocks, radio-activity, and lastly a useful chapter on the collection of material and the preparation of thin sections. Chapter ix on the origin and variation of igneous rocks is full of interest, as it contains the author’s ideas resulting from a large amount of field work, and in it he states a very strong case for the origin of igneous rocks from ‘refusion’. The chapters on the metamorphic rocks also contain much original matter and discussions of many controversial questions. Throughout the book a great many of the rocks taken as examples are from South African and Australian occurrences, so that the book will doubtless be found most useful by geologists working in those parts of the empire. V.—Tue Acx or THE Earrn. By Arruur Hommes. 8vo; pp. xii-+ 195, with 4 plates, 5 text-figures, and 5 diagrams. London and New York: Harper & Brothers, 1913. Price: cloth, 2s. 6d. net ; leather, 3s. 6d. net. IY\HE problem of the age of the earth has occupied the attention of scientists repeatedly since the fourteenth century, and has been a frequent source of keen controversy. This little book has for its aim the criticism, in the light of recent work, of the various methods which have been applied to the solution of the problem. After a brief historical account the several methods are treated in detail. Kelvin’s estimate, based on the effect of tidal retardation on the shape of the earth, is passed over as being based on astronomical theories not generally accepted. As instances of attempts to connect sedimentation with astronomical data, the work of Croll and of De Geer on the date of the culmination of the Glacial period is quoted. In the same chapter is a review of Gilbert’s attempt to connect the regular alternations of limestone and shale in the Upper Cretaceous of Colorado with the position of perihelion. The work of denudation is considered in the light of the available data for several large rivers, and of Dr. F. W. Clarke’s recent estimates of solvent denudation. It is estimated that 9,000 million tons of material are deposited annually on the continental shelves. The time-worn method of determining the age of the oceans from measurements of the ratio of accumulated sodium to the annual increment is discussed in detail. By introducing numerous corrections it is possible to arrive at ages varying from 80 to 340 million years, Reviews—S. 8. Buckman— Yorkshire Type Ammonites. 377 and, as all the corrections are based on insufficient data, it is shown that the method is extremely unreliable. In the chapter on the relation of sedimentation to geological ie the previous estimates based on the thickness of sediments are tabulated. Of these the three most recent, those of Geikie, Joly, and Sollas, vary between 80 and 100 million years. The author points out four further methods by which one arrives at ages varying from 250 to 850 million years, with a possible upper limit of 700 million. It is held that we may be living in an age of more than average sedimentation, in support of which opinion a communica- tion from Professor Chamberlain is quoted. The author has no confidence in purely geological methods for determining the earth’s age. He is, however, enthusiastic on the possibilities brought to light by the study of radio-activity in the rocks, a subject on which he has done much original work. The accounts of recent research on radio-activity, of the disintegra- tion theory, and of the measurement of radio-activity in rocks, are well written. The work of Joly and Fletcher on pleochroic haloes is reviewed, and it is pointed out that these haloes, after further study, may be used as an indication of the ages of the minerals in which they occur. The chapter on radio-active minerals is a very important one, giving a lucid account of the refined methods of estimating the age of rocks by determining the ratio of helium to uranium, or of lead to uranium, in the radio-active uranium minerals. The work of Strutt, Boltwood, and Rutherford is described, and the author has also given us the results of some of his own experiments. For Archean rocks measurements of the’ ‘helium ratio’ give an age of 700 million years; measurements of the ‘lead ratio’, however, give double that figure. In the last chapter the author reviews all the evidence, and endeavours to show in what directions one must look for a recon- ciliation between the new and the older methods of determining the age of the earth. There are two useful appendices, one giving various data referred to in the chapters on radio-activity, the other giving a very complete bibliography of the whole scope of the book. In the small space at his disposal the author has handled a vast subject in a very able manner. VI.—Yorxsuire Tyrpr Ammonites. Edited byS.8. Buckman. The original descriptions reprinted and illustrated by figures of the types reproduced from photographs mainly by J. W. Tutcher. Part ix, 10 plates, with descriptions. London: Wesley, 1913. ITH this part begins vol. ii of this exceedingly important work. It was long recognized that until some master hand had examined, redescribed, and figured the numerous species of Lias Ammonites from Yorkshire that had been named by Martin Simpson little progress could be made in this fanna. Mr. Buckman essayed the task, and every species that he deals with clears up ground of a most uncertain and treacherous nature. And now that he is well 378 Reviews—Brief Notices. into the work, it is for paleontologists to see that he is enabled to complete it. Mr. Buckman’s procedure is to print the original diagnosis, to give additional details, and then to discuss and amplify them, recording his result in a final paragraph fixing the nomenclature. Such work is of the highest possible value, for until we have cleared up and fixed old types it is merely beating the air to describe new ones, We are glad to see that the author tabulates and explains once more his terminology and his zones, as that renders his position and work quite clear and comprehensive. For Mr. Tutcher’s photographs we have nothing but praise. With a critical knowledge of the forms and their details, he has mastered his art, and the,combined efforts of the two friends has laid all students of the Ammonites under a great debt. More subscribers are, however, needed to push the work forward to a more rapid completion. VII.—Brier Nortces. 1. YorKsHireE Puinosopnicat Socrery.—The Annual Report of this Society for 1912 contains a notice of the building of a new lecture theatre, erected by the influence of the President, Dr. Tempest Anderson, and formally opened by Professor T. G. Bonney, F.R.S., who delivered a discourse on the ‘‘ Development of Education ”’. 2. CampripGe Puivosopaicat Socrrry.—T'o the Proceedings of this Society (vol. xvii, 1913) Mr. R. H. Rastall has contributed notes on ‘“The Mineral Composition of some Cambridgeshire Sands and Gravels’’, including Plateau and River Gravels and wind-drifted surface-deposits. While the most abundant material in all the sands is naturally quartz, it is interesting to find that ‘“‘ next in abundance is flint in white opaque grains, often well rounded”’. Other minerals are glauconite, tourmaline, kyanite, staurolite, garnet, hornblende, augite, hypersthene, and epidote, while there is an almost complete absence of muscovite. The author concludes that ‘‘the materials have been derived from two-sources, partly from the Neocomian sands of Cambridgeshire and the neighbourhood of the Wash, and partly from far-distant sources by ice-transit, that is, from the solid matter transported on and in the ice from Norway, Scotland, and the north of England”’. In another paper on ‘‘The Minerals of some Sands and Gravels near Newmarket” the most notable heavy minerals recorded are zircon and rutile, while kyanite, staurolite, and tourmaline are rare or absent. Moreover, in certain beds of loam and marl muscovite proved to be abundant. 3. Sourn Arrican Vertrsrata.—lIn the Annals of the South African Museum (vol. vii, 1912) Dr. R. Broom describes a new species of Propappus, and expresses his opinion that this genus and the allied Pareiasaurus ‘‘were heavily built animals which probably walked with slow, deliberate movements, such as we see in the large tortoises. They were land animals, and it seems more likely that they lived even on the dry land than that they frequented the marshes. The structure of the claws and the humerus would seem to indicate that they were digging animals, and probably, like the Eehidna, they Reviews—Brief Notices. 379 defended themselves from their carnivorous enemies by digging into the ground”’. In a second paper Dr. Broom describes a species of Zylosaurus (a Pythonomorph) from the Upper Cretaceous beds of Pondoland ; in a third paper he gives an account of a new type of Cynodont from the Stormberg named Ziitheledon riconor, while the new family is called the Tritheledontide; and in a fourth paper he discusses some points in the Dicynodont skull. 4. Pierstocene Grotocy oF New York Sratze.—This formed the subject of the annual address to the Geological Society of America, Mr. Herman L. Fairchild, President (Bull. Geol. Soc. Am., xxiv, 1913). The author discusses the limits, thickness, movement, and recession of the ice, its erosional and constructional work together with that of glacial waters in connexion with drumlins, moraines, eskers (sub-glacial), kames (extra-glacial), and other features. In conclusion he refers to Glacial time, remarking that ‘‘the estimates of those best qualified to judge of the length of Pleistocene time are from 500,000 to 1,500,000 years”’. 5. Norra American Camets.—After six years excavation at La Brea, California, the University of California has been so fortunate as to obtain several nearly perfect skulls of Camelops hesternus, and varieties with associated skeletal material representing the greater part of the animal. This has enabled Dr. Merriam to revise all previous work on the group and speak with more certainty as to the many species raised on imperfect material. (Univ. Calif. Publ., Bull. Dept. Geol., vii (14), pp. 305-28, May, 19138.) 6. Taz Manus or ZTracHopon.—A well-preserved skeleton of Trachodon marginatus, Lambe, from the Edmonton formation of the Red Deer River, Alberta, Canada, has allowed Mr. L. M. Lambe to describe the manus in detail. ‘This differs materially from the description given by Barnum Brown of the manus of a specimen from the Lance formation of Wyoming in 1912. That species was called T. annectens. About four feet of the tuberculated skin is preserved in the new specimen. Mr. Lambe gives a full account of the manus and three plates in the Ottawa Naturalist, May, 1913. 7. Roap-merat.—The following paragraph is reprinted from reports for the year 1912, on the Geological Survey, the Geological Museum in Jermyn Street, etc. (P.P., Cd. 6793), 1913: What is essentially a new departure in the work of the Geological Survey of Scotland was made in 1912. The Argyllshire County Council, recognizing the importance of utilizing to the best advantage the great variety of stones suitable for road-metal in that county, desired to purchase a series of road-stone maps showing the occurrence of road-stones in places easily accessible from the main roads. Maps were prepared on the scale of six inches to one mile, on which were marked only the outcrops likely to be of importance for this purpose. The surveyors find them of great use, as the published one-inch maps are on too small a scale to show all the smaller intrusions of igneous rock, some of which make excellent road-stones. As they are not complete maps they are comparatively inexpensive to prepare. 380 Correspondence—R. M. Brydone. CORRESPONDENCE. THE DIVISION OF THE UPPER CHALK. Srr, —Mr. Jukes-Browne’s article under this heading in the April number divides itself naturally into two parts, one dealing with the personal aspect, the other (not altogether impersonally) with the scientific aspect. As for the personal aspect, the position is as follows: Certain observations as to faunal changes within the old zone of A. guadratus were judged at the time of the publeation of ‘The Zones of the Chalk in Hants” not to amount to evidence of zonal breaks; they were therefore treated as indicating the existence of subzonal breaks, whose exact position and nature were then not yet ascertained. A large body of further observations enabled me to define the exact position and nature of these breaks and showed that one of them was of zonal importance, involving the proposal of a new zone. Mr. Jukes-Browne announced this intended proposal of mine in such a form that the natural inference was that it was a mere reshuffling of the. data already published—the last thing I desired, and forced upon me by some one else’s unauthorized version of my unpublished work. As for the scientific aspect, some of the points originally raised (or which could be raised on his reply) are not of sufficient general interest to justify further elaboration. Of the broader points, what was expressly stated to be a fact concerning the Yorkshire cliffs is now admitted to be an assumption ; and the tabulation of records from the old zone of A. quadratus in Sussex under the new zone of O. pilula, a representation of fact, is now admitted to be based on an assumption which happens to be false, there being at least 100 feet of the restricted zone of A. guadratus exposed in the Sussex cliffs. Surely it is not very ‘‘ captious” to object to these assumptions being presented as established facts. My. Jukes-Browne was xoé told by me that he ‘‘ had no right”’ to make the assumption as to Yorkshire. He is entitled to make any assumption; his grounds for making it are then a legitimate subject of criticism. Several broad points seem to go by default, e.g. that the highest Yorkshire chalk is so far North-German in its apparent affinities that its nomenclature should be North-German rather than Anglo-Parisian, and its fossils should not be mixed up with those of the Anglo-Parisian chalk of Sussex; or again, that records from Yorkshire, where no chalk of the restricted zone of A. guadratus is admitted to be preserved, cannot logically be used to prove the absence of certain species in that epoch. If this were logical it could be proved that in Kent all the common fossils of the Chalk died out in the zone of Marsupites. Mr. Jukes- Browne now writes of a ‘‘ Yorkshire zone of A. granulatus’’, a zone quite novel to me. It would be interesting to know where to find a definition of this zone and how it is distinguished from the zone of O. pilula or Scaphites binodosus, or again, from Dr. Rowe’s ‘‘ local zone of Znoceramus lingua” Mr. Jukes-Browne’s challenge to me to prove that A. granulatus does occur in the restricted zone of A. guadratus is really irrelevant. Correspondence—A. Rk. Horwood. | 381 I have not stated that 4. granulatus does occur there, and if I could not point to an undoubted 4. granulatus from a horizon at which any Belemnites are most exceptional occurrences it would not prove that A. granulatus never occurs there, as assumed by Mr. Jukes-Browne. It so happens that the challenge can be met out of his own mouth. He says: ‘‘ With respect to Sussex I relied on the published records, according to which . . . in the cliffs between Seaford and Brighton ... A. granulatus occurred through at least the lower 150 feet.” As the zone of O. pilula is only from 100 to 110 feet thick in the Sussex cliffs (and does not exceed 105 feet at Seaford), A. granulatus at 150 feet must be well up in the restricted zone of A. guadratus. Specimens of 4. granulatus occurring at 120 feet would be equally, though less deeply, in the restricted zone of A. quadratus. R. M. Brypons. 27 TWYFORD MANSIONS, W. THE LHICHSTERSHIRE AND SOUTH DERBYSHIRE COAL-FIELD. Srr,—I shall be much obliged if any readers of the GroLoctcaL Magazine can inform me of the whereabouts of a collection of Coal- measure fossils, chiefly plants, made by Edward Mammatt, author of Geological Facts. He was the first man, as a pupil of William Smith, to put into practice for Carboniferous zonal work the principle that strata are characterized by their organic remains. A detailed coloured section is given in his work, with the position of fossils found indicated. Moreover, these fossils are figured in his work, but unfortunately in the state of lithography at that time accuracy was not possible, and it would be necessary to examine the originals in many cases to be sure what fossilisintended. So valuable is this record, since the sections are now bricked in, that the information the fossils could afford would be of the greatest assistance to me in further working out the paleontology of this coal-field. Mammatt was a friend of the late Professor A. H. Green, who surveyed part of the district, afterwards going to Oxford. Inquiries were made amongst several colleagues when my preliminary account of this coal-field was communicated to the Survey memoir on this coal-field, published in 1907, but I was then unable to obtain any information. Since I am hoping to revise this account, which was drawn up before the work had gone very far, and as I have a good deal of additional information, any facts of importance that may be known to readers of this Magazine will be cordially welcomed. When the above-mentioned degen was written, reliance had to be placed upon certain data which may, after a fuller study of the question, have to be read in a new light, in spite of the fact that my friend the late Mr. Fox-Strangways and I were satisfied with them at the time. It is in this connexion that Mammatt’s sections are specially interesting.— Yours truly, A. R. Horwoop. LEICESTER MUSEUM. July 9, 1918. / 382 Obituary—Sir Jonathan Hutchinson. Oh Gi Aske SIR JONATHAN HUTCHINSON, KT., EARS. (MD: “DE.D:; BRS. BORN JULY 23, 1828. DIED JUNE, 1913. In Sir Jonathan Hutchinson there has just passed away in his 85th year an eminent physician, a Fellow and (in 1889 and 1890) Hunterian Professor of the Royal College of Surgeons, most distinguished as a specialist in diseases of the skin; elected a Fellow of the Royal Society (1882); one of the most kindly and unselfish of men, ever ready to do good to others. Outside the medical profession —to which he devoted a long and laborious life, and spent much money and time in advancing—his pet idea was that the establishment of small local museums, scattered about the country, would be of the greatest value as aids to education. He himself established and supported two such, one at Selby in Yorkshire (his birthplace) and the other at Haslemere, at which latter place was his home,! and where he retired after a long and strenuous career as a medical man. Although intensely interested in geology, he could from his well- stored mind address an audience on a great variety of subjects, and was never so happy as when lecturing to a roomful of country people or to young folks. The pleasure of imparting information to others was only equalled by the eagerness with which he sought and acquired knowledge. History, poetry, archeology, botany, and geology all in turn attracted his attention and were studied with care. Even when 78 years of age, he travelled thousands of miles in India and Cape Colony in pursuit of his investigation into the cause and origin of leprosy, eager to help to relieve the sufferers and, if possible, to eure them. Like his colleague Sir Joseph Lister (both members of the Society of Friends), Jonathan Hutchinson leaves behind him the record of a life devoted to the welfare of his fellow-men and the relief of human suffering. DR.) .P2 LU TLEY, SCLATER, SMVA. yh Rae BorN NOVEMBER 4, 1829. DIED JUNE 27, 1913. We much regret to record the death of Philip Lutley Sclater, M.A., D.Se.,,Ph.D., F-R.S5 ELS:, E:G:8.,. F.R.GS., Hon! Heliaw-or Corpus Christi College, Oxford, at his country seat, Odiham Priory, Winchfield, Hampshire, at the advanced age of 84. He was the second son of William Lutley Sclater (his elder brother being the Right Hon. G. Sclater-Booth, afterwards Lord Basing). He was educated at Twyford and Winchester, where he obtained a scholarship at Corpus, and took his degree and a first in mathematics at Oxford in 1849, remaining there two years afterwards. Later Dr. Sclater entered Lincoln’s Inn, and was called to the Bar in 1855. Under the influence of Strickland he took up ornithology, and spent some years in travelling in Italy, Sicily, Canada, and the United States. Later on he visited Morocco, Egypt, South Africa, and the West Indies. 1 The Library, Inval, Haslemere. Obituary—P. Lutley Sclater. 383 He was one of the founders of the British Ornithologists’ Union, and was editor of the /ézs for over fifty years. He contributed several bird-catalogues to the British Museum, and was recognized as one of the leaders of systematic zoology. He became a Fellow of the Zoological Society in 1850 and was elected Secretary in 1859, which office he held until 1902 (a period of forty-three years), when he retired on a pension. He was deeply interested in the scientific side of zoology, and largely promoted the publication of the Zoological Record (founded in 1864), which he induced the Zoological Society to aid by an annual grant and to be wholly responsible for from 1866 to nearly the present time. Dr. Sclater was also keenly interested in promoting the carrying on of the Index Generum et Specierum Animalium, by Mr. Charles Davies Sherborn, F.G.S., F.Z.S., which was commenced by the author in July, 1890, and is stv 7m progress—a stupendous undertaking to be carried out by the labour of one man. At the date of the first notice (Proc. Zool. Soc., 1896, p. 610) 130,000 slips had already been stored away in alphabetical order (see Guon. Mae., 1896, pp. 557-61). The first volume of this famous work, which occupied eight years in its production, was issued in 1902 by the Cambridge University Press, and embraced all names from January 1, 1758, to December, 1800, and contains 61,600 entries. The work, under the support of a committee, has been continued, and each year its author has issued -areport of progress. The slips are stored in the Natural History Museum, where they are always accessible to all workers in zoology. As regards the continuation of this important undertaking, Pr. Sclater had the pleasing satisfaction to know in April of last year (1912) that the Trustees of the British Museum had resolved to take over the work of the compilation of the Index Animalum, and had given Mr. Sherborn rank as a ‘‘ Special Assistant ’’ on the staff of the British Museum (Natural History). One who knew Philip Lutley Sclater well writes: ‘‘ The death of Dr. Sclater deprives many of a real friend, and science in general of a warm supporter. A zoologist primarily, he yet found time to take an interest in geology, and was ever ready to learn what geology had to teach in the elucidation of questions of geographical distri- bution and evolution. As Secretary to the Zoological Society he had often led parties of geologists around the Gardens.” We cannot conclude this brief notice of Dr. Sclater’s valuable services to science without a passing reference to his important contribution to the study of the geographical distribution of animals. In 1858? he discussed the primary zoological divisions of the earth, taking birds as the basis, and designated six great regions, which he named the Palearctic, Athiopian, Indian, Australian, Nearctic, and Neotropical. Although the general tendency at present is to unite several of these regions together, they nevertheless have proved of great service to paleozoologists in dealing with the broad questions of geographical distribution of animals in the past, and it is interesting to find how far Dr. Sclater’s studies in zoology had advanced our 1 Journ. Proc. Linn. Soc. (Zoology), vol. ii, pp. 130-45 (1858). 4 384 Obituary— James Logan Lobley. knowledge more than fifty yearsago, even before Wallace and Darwin had entered the field. Dr. Sclater’s eldest son, Mr. W. L. Sclater, M.A., like his father, is distinguished as a systematic zoologist. JAMES LOGAN LOBLEY, F.G.S. Born 1833. DIED JUNE 27, 1913. By the death of J. Logan Lobley the Geologists’ Association of London have lost one of their earliest friends. In 1865 he became a member of the Association and a Fellow of the Geological Society, but most of his attention was bestowed on the younger body, of which he was Honorary Secretary and Editor 1871-3, Editor alone till 1881, and Treasurer 1881-5. Deeply interested in the field-work of the Association he conducted many excursions, and those to the Weald of Kent, in 1879 and 1882, will long be remembered by many who took part in them. Lobley’s chief written work was his Mount Vesuvius, 1868, expanded from a pamphlet to a volume in 1889. He also wrote a separate volume on Hampstead Hill in 1889, and contributed a score of papers on various subjects to the GzoLoercaL Magazine and other serials. From a position of comparative affluence fortune had laid him low, and his later years had been sad ones, in which he had eked out a poor living by coaching explorers and others in his favourite science. But he worked on to the last and passed away at the age of 80, at 36 Palace Street, S.W., just a few days before the announcement that the Government had awarded him a Civil List Pension of £60, of which he had already drawn a very welcome instalment, lightening the trouble of his last few months. He was buried at Hampstead Cemetery on July 1, attended by Dr. W. S. Bruce, the Antarctic explorer, and a few other devoted friends from the Geological Society and the Geologists’ Association. MISCEHLILUANHOUS. We learn from Nature (May 29, 19138) that a ‘‘new iron Bacterium”? has been described by Mr. E. M. Mumford in the Transactions of the Chemical Society. It was discovered in the Bridgewater Canal tunnels at Wasley, Lancashire, where the water contains much iron derived from colliery pump-water. The new bacterium appears to have a twofold action, an aérobic action whereby it precipitates ferric hydroxide from iron solutions, and an anaérobic action which transforms the ferric hydroxide into bog iron ore with partial reduction of the iron to a ferrous state. RETIREMENT OF ProFessor C. Lapworru, F.R.S.—We learn that Professor W. 8. Boulton, B.Se., F.G.S., Assoc. R.C.S., Professor of Geology at University College, Cardiff, has been appointed to succeed Professor ©. Lapworth, F.R.S., who is retiring at the close of the present session. Before his appointment to University College, Cardiff, Professor Boulton had been assistant lecturer.in geology at Mason College under Professor Lapworth (Nature, June 12, 1913). - BRITISH MUSEUM (NATURAL HISTORY) NEW PUBLICATIONS (continued). Be ciclosue of the Collection of Birds’ Eggs in the British Museum (Natural History). Vol. V. Carinate (Passeri- formes completed). By W. R. Ocimvim-Granr. 8vo. pp. xxiii, 547, with 22 coloured plates. 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The late Henry Johnson Collection of Fossils, comprising Coal-measure Plant and Animal Specimens (Coseley), Wenlock Limestone Specimens (Dudley Castle Hill, The Wren’s Nest, and Tividale), and miscellaneous Mineral Specimens, Spars, etc. For appointment to inspect, and further information, apply to— C. N. JOHNSON, 19 Priory Street, DUDLEY. JUST PUBLISHED. CATALOGUE OF GEOLOGICAL WORKS No. 15—Dynamical, Palaeontological, and Stratigraphical. Post free on application. All Communications for this Magazine snould be addressed to THE EDITOR, 13 Arundel Gardens, Notting Hill, London, W. 300ks and Specimens to be addressed to the Editor as usual, care of MESSRS. DULAU & CO., LTD., 37 SOHO SQUARE, W. STEPHEN AUSTIN AND SONS, LTD., PRINTERS, HERTFORD. eNok ats Ie SP eae Pa pe eee a ae Se Ce oe oe oe '- On the genus Syringothyris. Monthly Journal of Geology. WITH WHICH IS INCORPORATED THH GHOLOGIST. HENRY WOODWARD, Tinie Wes GEORGK PROFESSOR Dr. Sir THOMAS H. HOLLAND, K.C.1.E., Se. SMITH WOODWARD, F.R.S. HORACE B. WOODWARD, F.R.S., F G.S\ < yy Proressor W. W. WATTS, Dr. ARTHUR EDITED BY ASSI J. D., CED F.R.S., F.G.S., &c. STED BY GREGORY, D.Sc., F.R.S., F.G.S. WINDE, F.R.S., F.G.8. AwR.CsS., DSi: R.S.. 1G.Se M.Sc., F.R.S., Vicu-Pris. Geor, Soa _ Le x Lo BeleeSes Gepa.§ Sor. fnoge b SEPTEMBER, 1918. SEP15 1913 CO aN be eS I. ORIGINAL ARTICLES. The Origin of Mountains. By ~ Colonel S. G. BURRARD, C.S.1., -R.E., F.R.S8., Surveyor- “General of India soe The Beaufort Beds, ‘South Africa. By D. M. S. Watson, M.Sc., University College, London By EF. J. NortH, B.Sc., King’s College, London. (Plate XII.) Lower Pliensbachian—‘ Carixian ’ —of Charmouth. By W. D. Lane, M.A., F.G.8. (With 3 Page-sections.) ... The Bermuda Islands. “By Major A. J. PEIE, R.A. ... Buried River Channel, Peterborough. By A. IRVING, D.Se., BoA oun. Striations upon Flint. By J. REID Morr, F.G.S. II. NOTICES OF ENOTES: Geological SSR Southern Rho- - desia Ss Iii. Reviews. Dr. F. A. Bather’s Cystidea from Girvan. (Plate XIII.) ...... Professor Hans Gadow’s Wanderings of Animals . : H. B. Woodward’s Supplement to Geological Atlas.. LONDON : Page . 385 : 388 393 . 424 Nee \ tional Muse REVIEWS (continued). Page W. M. Newton’s Figures in Flint . 424 Dr. J. Ball’s Phosphates of Egypt. 425 Department of Mines, Canada ... 426 Magnetic Iron Sands, Quebec . 426 Brief Notices: Permo-Carboniferous Ice Age, Western Australia— Geological Survey and Mining in South Australia—Indian Aero- lites—Bernese Jura—Termites and Geology—Landes of Gascony 427 IV. REPORTS AND PROCEEDINGS. Geological Society, London— June 25, 1913 . 428 VY. CORRESPONDENCE. R. M. Brydone 430 A. J. Jukes-Browne 431 VI. OBITUARY. Prof. John Milne, D.Sc., F.R.S8. . 432 VII. MISCELLANEOUS. F. P. Kendall, Lecturer in Zoology at Wye. se 432, W. G. Fearnsides, Professor cE Geology, Sheffield ... . 432 Sir Archibald Geikie blecred a Trustee of British Museum ... 432 Professor J. W. Judd made an Emeritus Professor iP Bey DULAU & CO., Lrp., 37 SOHO SQUARE, Ws. Oy Ne oy THE. JOURNAL OF THE Bombay Natural History Society. EDITED BY W. S. MILLARD, R. A. SPENCE, and N. B. KINNEAR. Vol. XXII, No. 1. 8Svo. pp. 218, with 20 plates (two coloured). 13s. 4d. net. CONTENTS.—The Game ‘Birds of India, Burma, and Ceylon, Part IX, by K. C. STUART BAKER, F.Z.S.; Scientific Results from the Mammal Survey, by R. C. WRouGHTON, F.L.S., and KATHLEEN V. RyLery, III; A Popular Treatise on the Common Indian Snakes, Part XIX, by Major F. WALL, I.M.S., C.M.Z.S. ; The Bombay Natural History Society’s Mammal Survey of India ; Report on Collection No. 6, from Kanara, by R. C. WROUGHTON, F.Z.S., etc. ANNUAL SUBSCRIPTION - £2 2s. net, post free. (Three or four parts are issued annually.) SOLE AGENTS TO THE SOCIETY: DULAU & CO., Ltd., 37 Soho Square, London, W. to whom all Subscriptions should be sent. BRITISH MUSEUM (NATURAL HISTORY) NEW PUBLICATIONS. Catalogue of the Ungulate Mammals in the British Museum (Natural History). Vol. I: Artiodactyla, family Bovide, sub-families Bovine to Ovibovine (Cattle, Sheep, Goats, Chamois, Serows, Takin, Musk-Oxen, ete.). By R. LypDEKKER. 1913. S8vo. Illus. Cloth. 7s. 6d. Catalogue of the Books, Manuscripts, Maps, and Drawings in the British Museum (Natural History). Compiled by B. B. Woopwarp, Assistant in charge of the General Library, with some clerical assistance :— Vol. I. A—D. 1908. 4to. Cloth. £1. Vol. Il E—K. 1904. 4to. Cloth. £1. Vol. TI. L—O. ~ 1910. 4to:- Cloth.” £15 Vol. IV.. P—SN. 1913. 4to. Cloth. £1. THE GEOLOGIC AL MAGA ae NEW. SERIIESA (DECADE eV.) VOE. _No. IX.—_SEPTEMBER, 1913. ORIGINAL ARTICLES. 5 ee I.—Tue Ortein or Mountains. : By Colonel 8S. G. BURRARD, C.S.I., R.E., F.R.S., Surveyor-General of India. 1. The reply by the Rev. O. Fisher (Gzonoeican Macazine, June, 1918, p. 250) to Sir Thomas Holland’s note leads me to ask permission to place the geodetic case before your geological readers. I ask geologists to give a hearing to a geodetic computer. No living man has done more to encourage geodesists and to create a geological interest in their work than Osmond Fisher; no man has done so much to impress upon geologists that they cannot afford to ignore geodetic results as he has; no other man has had the advantage of being able to speak with authority both as a mathematician and as a geologist. We recognize the weight of his opinion. May I explain why we have the presumption to differ from some of his conclusions ? 2. Mr. Fisher has explained the origin of mountain ranges by what is known as the ‘floating crust hypothesis’, in which he assumes a solid crust floating upon a liquid substratum. He accepts the principle of isostasy in its entirety, and holds that mountain ranges are supported, not by the rigidity of the earth, but by floatation like icebergs. Geodetic computers find three objections to Mr. Fisher’s hypothesis : Firstly, we think that no hypothesis can be accepted now that is dependent upon the assumption of a liquid interior to the earth, and in this point we are in agreement with Sir Thomas Holland. Secondly, Fisher's hypothesis is not generally applicable to all continents and to all mountains, but has to be ‘amplified’ or ‘modified’ when any particular topographical feature comes under analysis. Thirdly, Fisher assumes that the depth of compensation of a mountain is directly proportional to its height above sea-level ; this assumption is opposed to the results of geodetic observations. 3. Mr. Fisher has argued that the rotation of the earth will give to the liquid interior an effective rigidity; but this rotation has conferred no rigidity upon our oceans, and even if it did render the liquid interior rigid, it would only do so in low latitudes where the rotation velocity is high. I understand, moreover, that the earth’s interior was assumed by Mr. Fisher to be liquid, in order to. explain the floatation of the crust. If the liquid is now proved to be rigid, the crust cannot be floating upon it. 4. I said above that Mr. Fisher’s theory is not generally applicable : may I explain what I mean? If he would define his theory in DECADE V.—VOL. X.—NO. IX. 26 386 Colonel Burrard—The Origin of Mountains. general terms, such as the following—‘ Every topographical feature standing above sea-level is compensated by an underlying deficiency of density, and that deficiency is uniform to a depth equal to ten times the height of the feature ’’—the geodetic computer could grapple with the problem. It is true that the basis of the Fisher theory is that each mountain has an attenuated root, and the depth of this root is always equal approximately to ten times the height of the mountain above it; but when computers come to apply this theory to actual topographical features they are met everywhere with local exceptions. In Northern India alone we have three such local exceptions: (1) The compensation of the Himalayas is said by Mr. Fisher to exist not only under the mountains themselves but to extend laterally beyond the Himalayan region. How can computers test a theory when the limits and size of the roots are not exactly defined? (2) According to Mr. Fisher’s general proposition mountains — have roots and valleys have none. But the Ganges valley is an exception; here the alluvial deposits are said to have been so heavy as to press downwards into the liquid substratum. It has thus a root of deficient density, just as if it werea mountain. How can computers deal with a valley that is not in accord with the general theory? If one valley is taken to be an exception to the general theory, how many others are to be treated as exceptions? (3) An advocate of the Fisher theory, writing in ature, May 8, 1913, discusses the Himalayas and their isostatic compensation. He then dismisses the Vindhya Mountains and their compensation as though they presented a different problem to be treated differently. But geodetic computers cannot alter their formule to suit every geological peculiarity ; they must be given a general theory which is applicable to the Himalayas, Vindhyas, Alps, and other ranges. They cannot compute Himalayan effects alone, and subsequently examine Vindhyan effects alone, for the two are interdependent. Computers have to regard Asia as a whole, and deal with it as such. 5. Two theories of mountain compensation have been placed before geodesists — Mr. Hayford’s and Mr. Fisher’s. According to the former the depth of compensation is everywhere the same, namely 70 miles, but the degree of compensation is larger for high mountains than for low. According to Mr. Fisher's theory the degree of compensation is always the same, but the depth to which that compensation extends is greater for high mountains than for low. Mr. Hayford varies the amount of compensation by altering its degree; Mr. Fisher varies it by altering its depth. Now if we test these two theories as stated above by the geodetic results of America and India we find Hayford’s strongly supported and Fisher’s contradicted. Hayford’s theory assumes constancy of depth, and this assumption we find borne out. Fisher’s assumes a greater depth of compensation for high mountains than for low, and this we do not find borne out. Hayford’s theory is applicable to a solid globe; Fisher’s is not. Hayford’s has explained both the large negative values of g that have been always found by observation to exist in the interiors of continents, and also the large positive Colonel Burrard—The Origin of Mountains. 387 values of g that have been met with on islands and coasts. Fisher’s theory does not explain these anomalies.’ 6. Although Mr. Hayford has shown that continents and mountains are generally compensated, yet we have no grounds for assuming that mountains maintain a constant height. The author of the theory. of isostasy said that it was not intended to account for the origin of mountains, and that it was only put forward to explain how existing -mountains were maintained. It has even been argued by others that as material is removed from peaks and crests by denudation the mountains become lighter and in consequence higher. This seems to me to be an unwarranted assumption based on no data whatever. In a similar way it has been stated that the rock floors of river valleys continue to sink as silt is deposited upon them, the underlying idea being that the weight of every additional layer of silt deposited is too much for the solid crust to support, and that the latter yields in consequence. Deep boreholes have been sunk in the deltas of certain rivers, and bones, shells, and remains of plants have been found at all levels, however deep the boreholes have been taken ; the conclusion has been drawn that these remains were originally deposited at sea-level. But let us consider the case of the Plains of Northern India. These extensive plains are deposits of silt brought down by rivers from the Himalayas. Boreholes have been sunk and remains of organic life found buried at great depths in the silt, but these observations do not justify the assumption that the rock-floors underlying the Indus—Ganges Valleys have been continually sinking under the increasing weight of the deposits. Both on the west and on the east long, deep, narrow, submarine troughs extend out into the oceans in continuation of the Indus and Ganges Valleys. The waters of the Indus and Ganges are continually pouring silt into these deep troughs; amongst the silt are remains of organic life that once flourished at sea-level—plants, shells, bones—and these are being deposited at great depths in the troughs. With this going on before our eyes how can we presume to argue that the remains found at great depths in boreholes were originally deposited at sea-level? The simplest explanation is that the plains of Northern India are concealing a sub-crustal crack, that the submarine troughs are con- tinuations of this crack, and that as the crack has opened and grown deeper the deposits filling it up have been continually sinking to lower levels. 7. The problem of isostasy that is now requiring solution may be stated as follows: ‘‘ Continents and mountains have been found to be compensated by underlying deficiencies of density; how has this condition resembling hydrostatic equilibrium arisen upon a solid 1 Although Hayford’s theory is the nearest approach to truth that has yet been made, it does not afford a complete explanation of every observed anomaly. In my paper on the origin of the Himalayas I corrected all geodetic results in accordance with the Hayfordian system, and I then regarded the uneliminated residuals as indications of actual departures from isostasy. Mr. Fisher calls attention to a change in the observed value of g at Dehra Dun that has taken place between 1870 and 1904. This change is, however, apparent only; it is due to the recent introduction of a correction for the vibration of the brick pillar upon which the pendulum is swung. 388 D. M.S. Watson—The Beaufort Beds, South Africa. globe of rock?”’ ‘The cores of continents and mountains are found generally to consist of crystalline igneous rocks, and the simplest explanation of isostasy seems to be that these crystalline igneous rocks have arisen from below by verticalexpansion. I beg to suggest that if great cracks occur at depths of miles in the sub-crust the rocks may be so disturbed by lateral pressure as to undergo chemical change, and to expand vertically. Mr. Fisher argues that lateral pressure should lead to increase of density. If rock be subjected to compression from all sides its density would increase, but if the pressure is from one side only, and the rock is able to escape vertically, an increase of density may not ensue. 8. Mr. Fisher states that any deep rift in our globe must at once be filled by heavy intrusive molten rock rising from below. He cannot accept the view that the solid globe may be cracking, and that the cracks are being filled by material from adove. But is the intrusion of molten rock from below dependent at all upon depth? Such intrusions are to be seen at high continental altitudes, whilst the great oceanic deeps remain unfilled by them. It is, I think, conceivable that the outer shells of a solid planet might become cracked in all directions, and that if the planet were devoid of atmosphere and oceans, as Mars possibly is, the cracks on its surface might be visible. If the outer shells of a solid globe were cracking, a condition resembling hydrostatic equilibrium might be produced. Asa crack was opening the lateral pressure would suffice to increase the elevation of ridges along its edges, and when the opening force declined the weight of the elevated ridges would tend to close the crack. There would thus be a resilience that would lead to oscillations of level. 9. Suess has suggested that the Himalaya Mountains are advancing southwards, and that the Japanese Islands are moving outwards towards the Pacific Ocean. The geodetic observations in India lead me, however, to believe that the Himalaya Mountains are being forced northwards by the opening of the Indus—Ganges crack, and that the Japanese Islands are being pressed backwards against the continent of Asia by the opening of the Tuscarora Deep. I think that the elevation of the Japanese Islands and their movement westwards as the Tuscarora Deep opens, may possibly teach us how continents and mountains originate and grow. II1.—Txe Beavrort Beds oF THE Karroo System or Sourn AFRICA. By D. M. S. Watson, M.Sc., Lecturer in Vertebrate Paleontology in University College, London. (F\HE great Karroo System of South Africa was divided by its discoverer, Andrew Geddes Bain, into four formations on litho- logical characters. They are— The StormBere Series. The Beavurort Beds. The Kcca Beds. The Dwyxa Series. It has long been recognized that the Dwyka conglomerate, which forms a large part of the lowest series, is of glacial origin, and the D. M. S. Watson—The Beaufort Beds, South Africa. 389 common occurrence of smoothed and striated pavements below it all along its northern exposure seems to show that it is the product of a great continental ice-sheet. It is my purpose in the present paper to Faiecues the mode of origin of the Beaufort Beds. These beds, which have long been famous for the wonderful reptilian fauna which they contain, form the Bieaten part of the Karroo and Orange Free State. The whole series has a thickness of roughly 9,000 feet, the rent bulk of which is composed of mudstones. These rocks are usually of very fine grain and, asarule, are not bedded; they often show banding, a difference of colour and texture, but are very seldom bedded; that is to say, it is usually impossible to expose a flat level surface of them, for they break into small cubical pieces so as to leave a quite irregular face. They are broken up by sandstones, usually impersistent, and usually also of very fine grain. In the middle of the series, on Great Winterberg, and also, so Dr. Broom informs me, on the Compass Berg, isa much more powerful development of sandstones of a massive kind and generally of coarser grain. The colour of the lower beds is usually dark grey or olive, the sandstones being of the same colour on fresh fractures, although they weather brown. The middle of the series, with the thick sandstone mentioned above, is of a lighter tone, the sandstone being yellow and the shales light green or red. The top of the series is almost entirely red in colour, with some green and yellow beds of sandstone and occasional purplish layers. Many unusual rock-types occur. In the upper beds the sandstones are almost invariably cornstones; that is to say, the angular sand- grains are scattered irregularly in an ophitic manner through large calcite crystals, whose cleavage remains quite apparent. The type is exactly similar to that found in the Upper Old Red Sandstone of Forfarshire. Another type of cornstone, seaennilae some of those in the Lower Old Red of Herefordshire, in which the crystals are not apparent and the included material is very fine mud, if any is present at all, is also common in the upper beds, where it often surrounds bones. In certain places masses of mudstone, usually of a purplish colour, are found, which are penetrated by irregular strings of calcite running ~ in the main more or less vertically, but often branching and having the appearance of the roots of a plant. In one case (Donnybrook, Upper Zwoort Kei, District Queenstown) I found in association with such a rock reniform masses of clear crystalline calcite, about 4 cm. in diameter, in a deep red mudstone. In the lower beds the mudstones contain immense numbers of nodules of irregular shapes, which are very hard and apparently only slightly calcareous; they sometimes surround bones, and their intractable nature adds much to the difficulty of working on South African fossil reptiles. Clay-pellet conglomerates are common, particularly in the upper beds, where they often contain small fragments of bone. Pebbles are almost entirely absent; except for two or three found by Dr. Broom, none are known from this thick and very widely spread system. 390 D. M.S. Watson—The Beaufort Beds, South Africa. The most remarkable features of the fossil contents which bear on the problem are— 1. The extraordinary rarity of Mollusca. During my own rather extended visit I saw no fossil shell of any kind, although they were carefully searched for. Dr. Broom, whose experience of the beds is unrivalled, has, I believe, only found one occurrence ; and Mr. Whaits, in the course of a very considerable examination of the lower zones, has never met with them. 2. Fish are very rare. The only large group, that from the Caledon River described by Dr. Broom, is contained in bedded sandstones, and judging from specimens in museums those from other horizons are also usually in bedded shales and sandstones. 3. The great rarity of plant-remains, except in the clay-gall conglomerates, where pieces of wood are often seen. The only plant. known to have been found in one of the mudstones that I am acquainted with is a bit of Schizonewra stem from Kuilspoort, District Beaufort West. 4. The fact that the definitely stratified shales very rarely yield any Tetrapod remains. Dr. Broom states that reptilian bones usually occur just below a sandstone, at the top of a mass of unstratified mudstone. This statement has been controverted by the Survey, but so far as my own observations go they support it, at any rate for the lower beds. 5. ‘Tetrapod remains occur sporadically, and very large areas are practically free from them, although the rocks may be quite similar to those of the same age which are richly fossiliferous in other areas. 6. Reptilian remains often occur in associated sets. In museums such groups are very rare, but this is largely because the great majority of fossils are picked up completely weathered out, and the nodule containing the skull is the most obvious part. The very careful collecting of Mr. Whaits from the Hndothiodon beds of the Beaufort West flats shows that by picking up all the small pieces of bone within a large area it is often possible to recover a good deal of the skeleton, even of such completely weathered-out specimens ; the individuals are so rare that the chance of mixing the bones of two of them is comparatively slight. Where the face on which a fossil is exposed is steep, it is difficult to discover how much of a scattered skeleton is present. In my own experience bones found in situ were almost always associated with other parts of the skeleton. A. G. Bain’s original manuscript catalogues show conclusively that many of the bones he sent to England were in associated lots. Reptilian remains sometimes occur in small groups, two or three individuals of the same or different individuals lying close together. 7. Yhe fact that a much larger percentage of the bones found in sandstones belong to Stegocephalia than is the case with those in mudstones. J first noticed this fact in the upper beds of the Burghersdorp district, and examination of the remains in museums seems to confirm it very strikingly. The problem of the mode of origin of the rocks which present the D. M. 8. Watson—The Beaufort Beds, South Africa. 391 remarkable features detailed above is a difficult one. Bain in his first paper recognized that they were not of marine origin because of the entire absence of all salt-water shells. He considered them of lacustrine origin, an explanation which seems to have satisfied most observers to the present day. Stow, however, seems to have been doubtful about it. It is interesting to compare the features of the Beaufort Beds recorded above with those of the Tertiary deposits of the Great Plains region of North America, also formerly considered as lacustrine. With suitable modification the following quotation from Leidy relating to them will apply to the Beaufort Series: ‘‘ Whilst the geological formation makes it appear that the fossils were deposited in ancient lakes, or in estuaries or streams connected with the latter, it is strange that they exhibit no traces of fishes or of aquatic molluses intermingled with the multitude of relics of terrestrial animals. . . . Even mammals of decidedly aquatic habitat are absent; with the exception of the shore-living rhinoceros and the beaver, no amphibions mammals have been discovered. Whilst the fossil bones are in perfect preservation, their original sharpness of outline without the slightest trace of erosion indicates quiet water with a soft muddy bottom.” The work of Matthew, Fraas, and Hatcher has shown conclusively that these deposits are not of lacustrine origin, but were laid down on vast flat plains as flood-plain and river- channel deposits modified by wind-action. Matthew has shown that the river-channel sandstones contain the remains of forest-.and river- ‘living animals, whilst the fine clays enclose the skeletons of plain- living types. The whole of the lines of evidence used by these geologists applies mutatis mutandis to the Beaufort Series. The vast majority of the Karroo reptiles are dry-land types. Dicynodon, which occurs throughout the entire series, is a large and very diverse genus, into which the Scotch Gordonia could be put; some of the South African types are, in fact, very similar to that form. Gordonia occurs in a sandstone all the grains of which are large and rounded, and in which the pebbles, occurring in thin impersistent bands, are all of characteristically wind-cut shapes; in fact, there is every reason to suppose that Gordonia is a desert animal. There can therefore be no doubt that Dicynodon is also a dry-land type. Besides the Pelecypods and fishes, the only types that we have any reason at all for regarding as aquatic are Lystrosaurus and the Stegocephalia, the presence of lateral line sense-organs on the skulls of which shows that they must have been to some extent water-living. I have pointed out above that the remains of fishes are apparently confined to the stratified shales and sandstones, and that the Stegocephalia, which are never common, are proportionately less rare in the sandstones. Of the only two Lystrosaurus localities I visited, one was in very obviously bedded sandstones, the other in sandstone and not so well- bedded shales. The thick mass of sandstone referred to above as occurring on the Great Winterberg is apparently in the zone which yields this reptile. 392 D. M.S. Watson—The Beaufort Beds, South Africa. We have therefore in the stratified and unstratified beds something of the same kind of difference of fauna that there is between Matthew’s river-channel and flood-plain types of deposits. The position in which skeletons are found is of interest. I know the position of seven skeletons of Parvasaurus as when found. In all cases the animal, which is a typical land-type, lay with its back upwards and its limbs still articulated ; one skeleton that I collected jay prone, with its forelegs symmetrically disposed, the humeri at right angles to the body, and the forearms and hands stretched forward parallel to it. The ribs were naturally disposed, and the two femora lay forward in contact with the body, with the legs stretched out sideways. The whole skeleton, except for the skull, which had been weathered out, was absolutely complete, and looked as if the animal had died quietly, and been covered up without the slightest disturbance by brown dust. A skeleton of Procolophon, only about 25cm. long, lies absolutely complete, with every bone articulated, in the position dead lizards usually assume, with the hind-limbs stretched backwards along the tail and the soles of the feet inward. Had the Beaufort Beds been deposited in a lake, the places where these skeletons were found would have been more than a hundred miles from its shore; is it conceivable that they could have been transported this distance and then deposited in the exact position in which they died ? The extreme fineness of all the sediments implies that the agent which deposited them was incapable of moving anything larger than a small sand-grain; is it conceivable that it could have carried along the huge bones of Pariasaurus and the Deinocephalia ? Had the Beaufort Beds been deposited in a huge lake, we should expect to find very finely bedded shales full of plants, shells, and fishes, and containing occasional scattered bones; instead we find great masses of unstratified rocks with many sets of associated bones, and only very rarely, and then in stratified beds, fishes and plants. The whole series of facts adduced above appear to me to be quite inexplicable on any lake theory of their origin, but receive a ready explanation if we suppose the deposits to have been laid down on land largely by wind-action, though also to some extent in small lakes or ponds, and perhaps wide and impersistent rivers. I think that it is not improbable that the curious cornstones may have had something to do with an efflorescence of calcareous matter similar to that which is now common in the Karroo. It may perhaps be interesting to compare the great unbedded masses of mudstone with loess, which they resemble in the fact that their constituent particles are, in the sections I have at present examined, always angular, a common feature in fine wind-borne material. In conclusion, I have to express my thanks to the Percy Sladen Trustees who assisted me to visit South Africa, and to many gentlemen there whose advice and assistance were of great service to me. I wish specially to thank Dr. R. Broom, Mr. D. V. Kannemeyer, and the Rey. Mr. Whaits. F. J. North—The genus Syringothyris. 393 BIBLIOGRAPHY. Bain, A. G., ‘‘On the Geology of South Afriea’’: Trans. Geol. Soc. Lond., ser. II, vol. vii, pp. 175-92, 1856. FRAAS, E.., Science, new ser., vol. xiv, pp. 210-12, 1901. HATCHER, J. B., ‘‘ Origin of the Oligocene and Miocene Deposits of the Great Plains’’: Proc. Amer. Phil. Soc., vol. xli, pp. 113-31, 1902. Leipy, J., The Extinct Mammalian Fauna of Dakota and Nebraska. Philadelphia, 1869. MatTTHEW, W. D., ‘‘ Fossil Mammals of the Territory of North-Eastern Colorado ’’: Mem. Amer. Mus. Nat. Hist., vol. i, pt. vii, 1901. IIJ.—On tHE cEenus SyrrngorHYris, WINCHELL. By FREDERICK J. NORTH, B.Sc., Assistant in the Geological Department, King’s College, London. (PLATE XII.) Introduction. Historical Review. General Account of the EIEN: like Structures in the Pedicle Valve of Syringothyris. Detailed Account of the Bimaetaes of the Tube-bearing Plate (Transverse Plate) in a specimen of Syringothyris aff. carteri (Hall). Relation between Syringothyris and certain Spirifers ; and the Origin of Syringothyris in North America. pi ecies eS 1. Intrropuction. IJ\HE following account of the genus Syringothyris is the result of work undertaken at the suggestion of Professor T. F. Sibly, and is intended as a preliminary to a revision of the British species of that genus, which I hope to present at some future date. Although it has long been known that Syringothyris possessed a distinctive internal structure referred to as a syrinx, or ‘‘a split tube between the dental plates’, the exact relations of that structure ‘had not been worked out, and it therefore seemed advisable to obtain a clear understanding of the characters of the genus, before attempting to deal with the mutual relations of its species. To Professor Sibly I have to express my thanks, not only for his valuable advice and assistance while the work has been in progress, but also for his kindness in placing the necessary material at my disposal for study. My thanks are also due to Dr. A. Smith Woodward, F.R.S., for permission to examine and section specimens in the British Museum (Natural History), South Kensington, and to Mr. R. B. Newton, F.G.S., for assistance in searching the collections in the Museum. 2. Hisroricat Review. The shell now known as Syringothyris cuspidata (Martin) was first described in 1796 by William Martin,’ who named it Anomia cuspidata. The true nature of the fossil Brachiopoda had not at that time been recognized, and Martin regarded his shell as an Anomiza, comparing its triangular fissure with the hole in the attached valve of that lamellibranch. The type-specimen, which is now preserved in the Sowerby Collection in the British Museum (Natural History), 1 Martin, 1796, pp. 44-50. 394 F. J. North—The genus Syringothyris. South Kensington, was found in the Carboniferous Limestone of Castleton. It shows only the external characters of the shell; there is no trace of a pseudodeltidium, and the delthyrium ‘is filled with matrix so that the tube-bearing plate which is characteristic of Syringothyris cannot be seen. In 1815 James Sowerby founded his genus Spirifer, with Anomia striata, Martin, as his genotype,’ and stated that he suspected Anomia cuspidata to have coils similar to those which he had observed in Anomia striata. This statement, and the fact that in Mineral Conchology, vol. ii, p. 48, 1818, which was published before the paper to the Linnean Society was printed, Sowerby mentioned the species cuspidatus as an example of his genus Sprrifer, led William King,’ Meek,® and others to regard S. cuspidatus as the genotype of Spirvfer ; but Davidson* has shown that Sowerby always regarded S. striata as the type-species of his genus. Spirifer cuspidatus was mentioned by various authors, but no additional characters were described until 1836, when G. P. Deshayes ® noted the presence of a plate (the pseudodeltidium) covering the delthyrial fissure. In 1855 F. M‘Coy® stated that in Spirifer cuspidatus (Martin) the triangular delthyrium often displayed ‘‘an internal deep-seated pseudodeltidium”’’. In the absence of a figure, it is not certain whether the structure referred to was the tube-bearing plate, but it is probable that it was since the upper surface of that plate is often seen between the so-called ‘dental plates’, a little below the level of the cardinal area of the shell. . In 1863 Alexander Winchell’ described certain fossils from the yellow sandstones beneath the Burlington Limestone (Lower Mississippian) of Iowa. Among these were shells which externally resembled Spirifer cuspidatus (Martin), but which possessed, in the pedicle valve, beneath the pseudodeltidium and between the so-called ‘dental plates’, an arched transverse plate. On the lower surface of this plate were two nearly parallel lamella, incurved at their free ends so as to nearly meet, forming a tube, incomplete along its lower surface, and projecting beyond the limits of the plate from which it originated. For these shells Winchell proposed the name Syringothyris, in allusion to the split-tube or syrinx, and the large triangular fissure or delthyrium. He named his type-specimen Syringothyris typa. Subsequently Davidson, King, and others observed that Spirifer cuspidatus (Martin) possessed a similar plate and syrinx; and these authorities regarded Syringothyris typa, Winchell, as synonymous with Spirifer cuspidatus (Syringothyris cuspidata). Schuchert,® however, pointed out small differences which led him to regard these two species as distinct forms. At the same time he concluded that Syringothyris typa (1863) was identical with Spirifer cartert, Hall, (1857), which latter shell first occurs in the Bedford Shale of Ohio (lowest division of the Mississippian). Accepting the specific value 1 Sowerby, 1818, p. 515. ? King, 1850, p. 125. 3 Meek, 1864, p. 19. 4 Davidson, vol. i, p. 81. ° Deshayes, 1836, p. 368. 6 M‘Coy, 1855, p. 426. Winchell, 1868, pp. 2-25. 8 Schuchert, 1889, pp. 28-37. F. J. North—The genus Syringothyris. 395 of the differences between S. cuspidata, Martin, and S. typa, Winchell, and also the identity of Syringothyris typa with Spirifer carters, Hall, the last-named species, having priority, becomes the type-spectes of the genus SYRINGOTHYRIS. The differences between Syringothyris cartert (Hall) and S. cuspo- data (Martin), as defined by Schuchert, are confined to external characters, and are as follows: the area of the pedicle valve is flat or concave in S. cartert, while in S. cuspidata it is usually reclined; and in S. cartert the lateral slopes of the pedicle valve are slightly convex, while in S. cuspidata they are flat or nearly flat. These differences are practically the same as those between Syringothyris aff. cuspidata, of authors, from the Cleistopora and Zaphrentis zones of the South-Western Province, and Martin’s specimen from the Viséan of Castleton, or S. cuspidata from the Carboniferous Limestone (Syringothyris-zone ?) of Kildare. Winchell did not figure any of his specimens, but Syringothyris typa has been figured by Hall & Clarke’ and S. cuspidata by Davidson ? and King? 8. GeneraL ACCOUNT OF THE PLATE-LIKE STRUCTURES IN THE PEDICLE VALVE oF SYRINGOTHYRIS. (1) The Delthyrium and Pseudodeltidium.—The cardinal area in the pedicle valve of Syringothyris is interrupted by a triangular del- thyrium .as in other brachiopods. It is only on rare oceasions that any plate is preserved covering the delthyrium, but occasionally the delthyrium is partly closed by a convex pseudodeltidium, the distal end of which is concave towards the apex of the shell, leaving a semicircular opening between itself and the hinge-line. Specimens in which this plate is preserved have been figured by Hall & Clarke * and Davidson. When the pseudodeltidium has been lost two grooves into which its edges fitted can often be seen, one on either side of the delthyrium. In Syringothyris cuspidata the pseudodeltidium has no foramen such as occurs in Oyrtia. Davidson® figured an internal cast of a pedicle valve from the Carboniferous Limestone of Breedon Hill, in which, he maintained, ‘‘the deltidium was in reality perforated by a circular foramen.”? His specimen shows, however, not a foramen in the pseudodeltidium, but a cast of the syrinx characteristic of Syringothyris. Some authors, for example, King’ and more recently Woods® and Cowper Reed,® have used the term deltidium for the covering plate 1 Hall & Clarke, 1894, pl. xxvi, figs. 6, 7, 10; pl. xxvii, figs. 1-3. : 2 Davidson, vol. ii, pl. viii, figs. 19-24; pl. ix, figs. 1, 2; vol. iv, pl. xxxiii, figs. 1-3. Hall & Clarke, 1894, pl. xxvii, fig. 15. Davidson, vol. iv, pl. xxxiii, fig. 1. Davidson, vol. ii, pl. viii, footnote, and pl. ix, fig. 1. King, 1850. Woods, Paleontology, Invertebrate, p. 157. Cambridge Natural History, vol. iii, p. 498, 1895. omonrIn a me 396 F. J. North—The genus Syringothyris. of the delthyrium in the Telotremata, but Hall & Clarke’ have shown that ‘ pseudodeltidium’ was proposed by Bronn for the fused condition of the deltidial plates that may occur in the Telotremata, while the term deltidium was intended to be used for the simple pedicle-secreted plate in the Protremata and in some Neotremata. Davidson used the terms indiscriminately, and referred to the plate in Syringothyris and the Spirifers generally, sometimes as a deltidium and sometimes as a pseudodeltidium. Hall & Clarke proposed to replace the terms ‘ deltidial plates’ and ‘pseudodeltidium’ by ‘deltaria’ and ‘deltarium’ respectively, but this seems unnecessary if the original definitions of deltidium and pseudodeltidium are adhered to. (2) The Delthyrial Supporting-plates.—Extending from the edges of the delthyrial fissure into the interior of the pedicle valve are the so-called ‘dental plates’ such as are developed in other brachiopods. They are slightly divergent, and in the neighbourhood of the apex reach the floor of the valve; but as the hinge-line is approached they become very shallow, and are widely separated from the floor of the valve. The function of these plates in the Orthotetids has been discussed by Dr. Ivor Thomas,? who suggests that they should be called delthyrial supporting-plates, since their almost complete disappearance before the teeth are reached would make it appear that their function is not so much to support the teeth, as to increase the stability of the area where it is interrupted by the fissure. This would apply with even greater force in the case of Syringothyris, where the area is so high; and the term ‘delthyrial supporting- plates’ will therefore be used in this paper in preference to ‘ dental plates’. (3) The Tube-bearing Plate, or Transverse Plate-—Connecting the vertical delthyrial supporting-plates is a horizontal plate which extends for from one-half to two-thirds of the distance from the apex to the hinge-line. This plate is not the pseudodeltidium, but lies below it. Its distal end is concave to the apex of the shell, and attached to its lower surface is an incomplete tube which projects for a short distance beyond the limits of the plate. On the upper surface of the plate there is a median longitudinal ridge. In passing from the apex towards the hinge-line the tube-bearing plate gradually plunges beneath the level of the cardinal area. This tube-bearing plate developed between the delthyrial supporting-plates of Syringothyris is the distinctive feature of the genus. As already mentioned, the general characters of this plate and tube have often been described, but their precise structure and relations have not been understood. This is probably due to the state of preservation of the shells examined. The structural details only become really clear when the shell is preserved in a fine-grained rock of such a colour that any shell structure which may be present is clearly defined. Most of the specimens from Derbyshire and Ireland are unfortunately filled with crystalline calcite, which tends to obscure the internal characters of the shell. 1 Hall & Clarke, 1894, pp. 327-8. * Ivor Thomas, 1910, pp. 100-1. F. J. North—The genus Syringothyris. 397 4, Derarrep Account oF THE STRUCTURE oF THE TUBE-BEARING Prateé (Transverse Prats) IN A SPECIMEN OF SYRINGOTHYRIS AFF. CARTERI (Hatr), (Plate XII.) The specimen here described was obtained by Professor T. F. Sibly from the Upper Cleistopora Zone (Ky) of the Post Office Quarry at Howle Hill, in the Forest of Dean area, Gloucestershire. It is of a type that is common in the Upper Clezstopora Zone and in the Zaphrentis Zone of the South-Western Province, and which, as mentioned by Dr. Vaughan,’ has broad flat ribs on the pedicle valve. This type of shell differs in certain respects (height and convexity of area, etc.) from the Derbyshire and Kildare specimens, and is more nearly related to Syringothyris cartert (Hall) than to S. cusprdata (Martin). The consideration of these differences is, however, best deferred until a future paper, when the species of Syringothyris will be dealt with in detail. Owing to the nature of the matrix, a fine-grained yellow limestone, and the excellent preservation of the shell substance, the specimen was peculiarly suitable for study of the internal characters. The pedicle valve of the shell was rubbed down in a plane at right angles to the area, and sections drawn at intervals of about half a millimetre. The beak of the valve was slightly damaged, and the first satisfactory section was obtained at a distance of 4mm. from the apex. The following sections are selected as illustrating the more important stages. (See Plate XII, Figs. 1-8.) Figs. 1 and la. Distance from the apex 4mm. In this section there are two strong divergent plates crossing the valve from the cardinal area to the floor. Each plate is divided longitudinally into halves by a distinct line. The outside moiety (the true delthyrial supporting-plate) in each case is continuous with the shell substance of the cardinal area, while the inside portion curves over at the top, and meeting its fellow from the opposite side forms an arch-shaped plate (the transverse plate) between the delthyrial supporting-plates, and which when seen from above appears as a septum connecting those plates. Figs. 2 and 2a. Distance from the apex 6mm. Here the sides of the arch-shaped plate are thinner than the delthyrial supporting- plates, which are themselves thinner than in the previous section. In the transverse portion of the arch there is a circular mark which represents the cavity of a tube, filled and obscured by shelly matter during the subsequent growth of the plate. On the upper surface of the plate there is a slight median ridge, also seen in the subsequent sections. Figs. 3 and 3a. Distance from the apex 1lmm. Between this section and the previous one, the delthyrial supporting-plates have become thinner at their bases, until in the present section one of them fails to reach the floor of the valve. The limbs of the arch- shaped plate are shorter than and thin out against the delthyrial supporting-plates. The outline of the tube or syrinx is very distinct, but its cavity is still filled with shelly matter. 1 Vaughan, Q.J.G.S., vol. lxi, p. 301, 1905. 398 F. J. North—The genus Syringothyris. Figs. 4 and 4a. Distance from the apex 14mm. The delthyrial supporting-plates are here very short. In the transverse plate the cavity of the tube and its inferior opening are very clear. This section, in which the transverse plate and split tube are perfectly developed, may be taken as a type-section of the essential characters of the genus, and constitutes a standard to which sections of other specimens can be referred. Figs. 5 and 5a. Distance from the apex 15mm. In the sections following that shown in Fig. 3, the limbs of the arch become shorter and shorter until they are mere flattenings of the edges of the trans- verse plate. The plate itself and the wall of the tube become thinner. The conditions at this stage are shown in Fig. 5. Figs. 6 and 6a, 7 and 7a. Distance from the apex 16 and 17 mm. respectively. The transverse plate eventually disappears, except for two small portions, one applied to each of the delthyrial supporting- plates, leaving the syrinx quite free as in Fig. 6. At the same time the syrinx becomes smaller and its walls thinner, while its roof assumes a folded aspect. In Fig. 7 the lateral portions of the trans- verse plate have disappeared, as have also the side walls of the syrinx, leaving only the roof of the syrinx, continuing as a ridged and folded lamella which becomes gradually smaller and finally disappears. (In this specimen, at a distance of 19 mm. from the apex of the shell.) In the earlier sections (Figs. 1-3) there is a low ridge on the floor of the valve between the delthyrial supporting-plates. This ridge or crest divides the anterior portion of the muscular impressions, and resembles the median crest which occurs in Spirifer, Productus, and many other brachiopods, but contrasts very strongly with the elevated median septum which occurs in a similar position in Spirvferina. In a band of dolomite in the Lower Zaphrentis Zone (Z,), exposed in the Cement Works Quarry at Mitcheldean, Glos, internal casts of Syringothyris of the type already described are abundant, and many specimens have been collected by Professor Sibly. The shell substance has been removed by solution, but the characters of the shell are very clearly shown by the matrix, with which the valve was filled. The delthyrial supporting-plates and the transverse plate are represented by space, and the cavity of the syrinx by a rod (r, Figs. 8, 8a) lying in a groove on the surface of the matrix that filled the chamber between the delthyrial supporting-plates. The lower surface of the rod is connected with the floor of the groove by a narrow plate representing the slit in the syrinx. The muscular impressions on the floor of the pedicle valve and the crest which separates them are clearly defined in these casts. It was from a similarly preserved specimen that Davidson inferred the presence of a foramen in the pseudodeltidium of Syringothyris cuspidata (see p. 395). We have seen that the transverse plate of Syringothyris arises in the apex of the shell as an arch-shaped plate, between and applied to the delthyrial supporting-plates, but not as an integral part of those plates. The syrinx occurs on the lower surface of the plate, F. J. North—The genus Syringothyris. 399 and is formed by two nearly parallel lamelle, the free ends of which curve towards one another. As the distance from the apex of the shell increases, the lateral portions of the arch become thinner and shorter until only its roof persists as the tube-bearing or transverse plate—a slightly convex plate, down the centre of which is a median ridge on the upper surface and a slit tube or syrinx on the lower surface. The transverse plate itself then dies out. Its distal end is concave towards the apex of the valve, and the syrinx projects for a short distance beyond it. The slit on the ventral surface of the tube tends to close, and the tube itself to be obscured by the further deposition of shelly matter on the earlier-formed portion of the transverse plate. In discussing the homology of the plate, Winchell? stated that in many Spirifers there is ‘(an indication of a longitudinal folding of the dental plates which may produce on one side or the other a laminar process’, and he suggested that the plate of Syringothyris may be of this nature, but in view of the sections that have been described this view appears to be untenable. 5. Rearion BETWEEN SYRINGOTHYRIS AND CERTAIN SPIRIFERS; AND THE Origin or SyringorHyris In NortH AMERICA. There is, developed between the delthyrial supporting-plates of certain Spirifers, a short transverse plate resembling in position and mode of origin the tube-bearing plate of Syringothyris; and the following sections (Plate XII, Figs. 9-11) across the beak of the pedicle valve of Spurifer duplicicosta, Phillips, from the Carboniferous Limestone (Viséan) of Park Hill, Derbyshire, may be compared with those of Syringothyris (Plate XII, Figs. 1-7). Fig. 9. Distance from the apex 3mm. This section should be compared with Fig. 1; at this stage the structure of the two shells is essentially the same. Fig. 10. Distance from the apex 5mm. This corresponds in position with Fig. 4, and it will be seen that although the relation between the transverse plate and the delthyrial supporting-plate is the same in each case, there is no trace of a tube in the present section. Fig. 11. Distance from the apex 8 mm. This section corresponds to a stage between Figs. 5 and 6. The plate is incomplete in the centre owing to its concave extremity as in Syringothyris, and in a further section, 11 mm. from the apex, it does not appear at all. A similar transverse plate was observed by the writer in a large specimen of Spirifer striata (Martin) from Kildare. King? claimed to have seen in a specimen of S. striata a transverse plate in which there was actually a tabular canal, but this has not been verified. Origin of Syringothyris im North America.—The plate just described as occurring in Spirifer duplicicosta, Phillips, and S. striata (Martin) is also found in many Devonian Spirifers of North America, and has been described and figured by Hall & Clarke,* who call it a delthyrial callosity. In North America there appears to have been 1 Winchell, 1863, p. 7. 2 King} 1868, p. 18, and pl. ii, fig. 25. 3 Hall & Clarke, 1894, pls. xxiii, xxiv, etc. 400 F. J. North—The genus Syringothyris. a gradual change from the simple plate extending across the delthyrial fissure in certain Spirifers, e.g. S. granulosus, Conrad (from the Hamilton Shale, Upper Middle Devonian), to the tube-bearing plate of Syringothyris ; while in other forms the plate has persisted without change, and occurs as a simple transverse plate in many Carboniferous Spirifers. A transitional stage is seen in Spirifer altus, Hall,’ where the transverse plate bears on its ventral surface a median longitudinal ridge. Girty,? indeed, regards Spirifer altus, Hall, as the direct progenitor of Syringothyris. The syrinx appears to have arisen by the growth of the lateral margins of the ridge, giving rise to two lamella, the free ends of which curled towards one another forming an incomplete tube. In North American Spirifers, therefore, the simple transverse plate developed between the delthyrial supporting- plates in certain Devonian forms gave rise to the tube-bearing plate of Syringothyris, and the earliest form in which the syrinx is perfectly developed is Syringothyris cartert (Hall) (=S. typa, Winchell) from the Bedford Shale (Lower Mississippian) of Ohio, which formation contuins a fauna allied to, and apparently in part derived from, the Middle Devonian Hamilton fauna.* In this country, however, the genus Syringothyris appears with all its essential characters in the Clerstopora Zone of the South- Western Province, and its early development is not known. Its ancestors may yet be found among the Devonian Spirifers of this country or Belgium. LIST OF WORKS CITED. 1796. Martin, W. ‘‘ Account of some species of Fossil Anomie found in Derbyshire’’: Trans. Linn. Soc., vol. iv, pp. 44-50. 1818. SOWERBY, JAMES. ‘‘Some account of the Spiral Tubes or Ligaments in the genus Terebratula of Lamarck as observed in several fossil shells’’: Trans. Linn. Soc., vol. xii, pp. 514-16. [Although com- municated in 1815 this paper was not printed until 1818.] 1836. DESHAYES, G. P. Animauzx sans vertébres, 2™° éd., vol. vii, p. 368. 1850. Kina, W. A Monograph of the Permian Fossils of England. Palzontographical Society. 1851-82. Davipson, T. British Fossil Brachiopoda, vols. i, ii,iv. Palsonto- graphical Society. 1855. M‘Coy,F. British Paleozoic Fossils in the Cambridge Museum, p. 426. 1863. WINCHELL, A. ‘‘Description of Fossils from the yellow sandstones lying beneath the Burlington Limestone at Burlington, Iowa’’: Proc. Acad. Nat. Sci. Philadelphia, vol. vii, pp. 2-25. 1864. MEEK, F. B., & HAYDEN, F. V. ‘‘ Paleontology of the Upper Missouri’’: Smithsonian Contributions to Knowledge, vol. xiv, pp. 16-20. 1867. Hawn, J. Natural History of New York: Palzontology, vol. iv. 1868. Kine, W. ‘‘ A Monograph of Spirifer cuspidatus, Martin’’: Ann. Mag. 1889. ScHUCHERT, C. ‘‘On Syringothyris, Winchell, and its American species’’: 9th Ann. Rep. State Geol. New York, pp. 28-37. 1894. Hau, J., & CLARKE, J. M. Natural History of New York: Paleon- tology, vol. viii, pt. ii. 1900. Girty,G.H. ‘‘ The Fauna of the Ouray Limestone’’: 20th Ann. Rep. U.S. Geol. Sury., pp. 31-63. 1 Hall, 1867, pp. 248-9, pl. xliii, figs. 1-7. A form allied on external characters to the European Spirifer simplex, Phillips. 2 Girty, 1900, p. 51. > Bailey Willis, 1912, p. 409. are a - RedcaralWe rie Te he satan aS Dicsie: Grou. Mae. 1913. Pratt XI. AS: ow games|) a (4 J \ i y ‘ y) Qu fro i Be Transverse sections of the pedicle valve of Syringothyris aff. cartert (Hall) and Spirifer duplicicosta, Phillips. W. D. Lang—Lower Pliensbachian of Charmouth. 401 1910. THomas, I. The British Carboniferous Orthotetine (Mem. Geol. Surv. Gt. Brit., Paleontology), vol. i, pt. ii, pp. 99-100. 1912. WILLIS, BArLEY. ‘Index to the Stratigraphy of North America’’: U.S. Geol. Surv., Prof. Paper 71, pp. 401-24. : EXPLANATION OF PLATE XII. Fies. 1-7. Syringothyris aff. carteri (Hall). Carboniferous Limestone f Series, Sub-zone K.: Howle Hill, Forest of Dean area. Transverse sections of pedicle valve. Natural size. », la-Ta. Delthyrial supporting-plates and. tube-bearing plate of the : previous sections, enlarged. x 3. » 88a. Syringothyris aff. cartert, Hall. Z,. Mitcheldean. Fig. 8, internal cast of the pedicle valve, diagrammatic, showing the rod (7) representing the cavity of the syrinx; Fig. 8a, transverse section, diagrammatic. » 9-11. Spirifer duplicicosta, Phillips. Carboniferous Limestone: Park Hill, Derbyshire. Transverse sections of the pedicle valve. x 3. In Fig. 11 only the central portion of the section is indicated. ITV.—Tue Lower PrirenspacntaAN—‘ Carrxtan ’—or CHARMOUTH. By W. D. LANG, M.A., F.G.S. I. Tue Green AmMonitE Beps. HE Green Ammonite Beds of the Lias (called also the Wear Cliff Beds in the latest Survey publication on Lyme Regis) ' include the clays with occasional limestones that he between the Belemnite Stone below and the lowest of the Three Tiers above. The lowest Tier contains ammonites of the margaritatus group,” and the Belemnite Stone caps the top beds of the Belemnite Marls that may be placed in the ibex—-valdani zone.* So the Green Ammonite Beds may be said to constitute the upper part of such of the Pliensbachian or ‘Charmouthian as lies below the. Domerian.t Buckman has applied the term ‘ Charmouthian ’ to this lower portion, thus restricting the term to a part only of what it originally included.® I have already advocated the propriety of applying the term Charmouthian strictly with its original connotation,® and would call those zones of it that le below the Domerian,—Bonarelli’s ‘Charmoutiano inferiore’— which certainly need an inclusive name, Carixian.’ The fullest published accounts of the Green Ammonite Beds are those in the ' Woodward & Ussher, The Geology of the Country near Sidmouth and Lyme Regis (Mem. Geol. Surv. Eng. and Wales), 1911, 2nd ed., p. 31. * Throughout this paper the phrase ‘‘ammonites of the — group ’’ is used, rather than the specific name of the ammonite, implying that several, presumably related forms are included under one designation. > On the evidence of Acanthoplewroceras ellipticum (James Sowerby), a form that comes very near to A. valdani. Myr. S. S. Buckman kindly identified this form for me. * Bonarelli, Atti della R. Accad. d. Scienze di Torino, vol. xxx, pp. 84-5, 1894. > Buckman, Yorkshire Type Ammonites, pt. ii, p. xvi, 1910. 6 Lang, GEOL. MaG., Dec. V, Vol. IX, p. 284, 1912. 7 “Charmouth, the Carixa of Ravennas’’ (Roberts, The History of Lyme Regis, Dorset, 1823, p. 220). The derivation seems obvious— Char-isca, * Char-river.’ DECADE V.—VOL. X.—NO. IX. 26 402 W. D. Lang—Lower Pliensbachian of Charmouth. Survey Memoirs,’ and may be summarized as follows: They extend from Black Ven on the west to Seatown on the east; traces only appear on Black Ven; the complete series occurs on Stonebarrow, though there ‘‘ only the lower portion is well-exposed”’; their thickness is about 100 feet, though variable, and as much as 125 feet to the east of Golden Cap; they consist of marly clays with ‘ferruginous bands’ and nodular limestones. Eight detailed sub- divisions are given. Now this description in the Survey Memoirs, though excellent as far as it goes, is not of much help for tracing the vertical distribution of the ammonites or other fossils contained in the beds here described ; the first step towards which is to be able to tell, when collecting in any section, the exact position in the series of the bed whence the specimens are being taken. For this it is necessary to know what lithic characters are constant throughout the whole exposure of the beds, and what are local accidents; also how the thickness of the whole series varies, so that measurements taken from the same bed at different spots may be correlated. It is proposed to give the strati- graphical results of some years’ collecting, both as a guide to future work and to supplement the descriptions in the Survey Memoirs. It may be here remarked that although adding to and even criticizing the account in the Survey Memoirs, this further description would never, probably, have been written without it; and these new sub- divisions are now put forward with full acknowledgment of the help obtained from the publications of the Survey. It must be stated also that the following remarks do not include the Green Ammonite Beds east of Golden Cap. From Golden Cap to Seatown (where they are faulted away)? is about a mile, and their total extent in the cliffs about four miles. It is therefore possible that any apparent discrepancies in the Survey Memoir may be due to observations made east of Golden Cap; as is certainly the case with the sandy beds recorded as appearing below the Three Tiers, of which the author has not found more than traces, nor these as a constant feature. Nevertheless, the similarity (except in thickness) of the Green Ammonite Beds from Black Ven through Stonebarrow to Golden Cap is so close that it would be surprising if they changed considerably in that eastern mile. Three constant and more or less continuous limestones break the monotony of the Green Ammonite clays (see DiagramsIT andII). The most conspicuous, continuous, and easily recognized of these is the Red Band. It is well known to the Charmouth fishermen, who, when they want (for sale to visitors) a ‘henleyi’ as they call ammonites of the striatus group, go up Stonebarrow and pick away at the Red Band. There can be no mistaking the curious pink-red weathering of this muddy limestone. When fresh, it is hard and firm; but being only about 6 inches to a foot thick, it is generally weathered nearly to the core, and is then grey-brown and in 1 Woodward & Ussher, op. cit., 1911; and op. cit., 1906, 1st ed.; H. B. Woodward, The Lias of England and Wales (Mem. Geol. Surv. United Kingdom), 1893, p. 68. 2 See H. B. Woodward, op. cit., 1893, p. 52. 403 yf Charmouth. Van O W. D. Lang—Lower Pliensbach 2 : Al Ss 4 f- q BY 2 hy S. 4 oA a 2h alk hy hy 2 ‘efit 8 Of sotfout Fe ynoqe eteog ‘“dvVQ NAGIOY OL NYA MOVIG NOU NOILOMY :] WVENVIG AOL QIU uULa)—a ay) DEE SP9 LMAO UooLD) ay) “suzy, 3344 [ oy) ee) WOPVNDIASH FY) moys » £2) UspPPOL) FY) UI, YOOVT wos Uu0NI0S D77VuLuLo1bo1C- YIM SPBWIOH 55 dngy Foyzsayy AQ) Em, —— 700% pfooe aioe H2, 2) 2704002 USS, LC firey U2 O07 OLED DUO) CEN PET — oe — — xfer yfoor afoor woyny fo wroW Soest ‘aun vag vamoy 3hooy —— -yfo0g — "yynoUwoy 404 W. D. Lang—Lower Pliensbachian of Charmouth. a crumbling, muddy condition, becoming pink-red on its surface. A little Crinoid is common and characteristic of it; also a NWucula; its commonest ammonites are those of the striatus group; TZrago- phylloceras loscombt (James Sowerby) and Deroceras davai (James Sowerby) also occur; as well as Nautilus and Gastropods. I have not found the Red Band in place on Black Ven, but fallen blocks may be found above the Lower Limestone at the extreme eastern outcrop of the Green Ammonite Beds on that cliff, showing that it is just included there before the Lias is truncated by the Gault. Some twenty yards west of where the blocks were found there was a section’ (now unfortunately foundered) showing the junction of the Lias and Gault. The Lower Limestone was to be seen in place some seven feet above the Belemnite Stone, six feet of clay above the Lower Limestone, and then the junction before the Red Band was reached. So the Red Band has a very short range on Black Ven. On Stonebarrow Cliff it may be found west of Fairy Dell,? on the slope of broken ground above the precipice formed by the Belemnite Marls, at some height above the 200 ft. contour-line, and followed across the grassy places until, still before Fairy Dell is reached, its outcrop is mostly on the cliff-face. Thence it runs eastward under the more inaccessible parts of Fairy Dell, sometimes on the cliff-face, but generally on broken ground above the clean section. It is conspicuous just above the 100ft. contour in a semicircular section on the undercliff between Westhay Farm and the sea, close to the ‘y’ in ‘ Folly’ on the six-inch Ordnance Survey map, and again immediately west of Westhay Water at 1065 feet, and may be seen at the head of the gully above the waterfall of that stream. ‘he red weathering of the top and bottom surfaces, in contrast to the grey middle, is so marked in the Red Band as seen near Westhay Water that the Band appears from a distance to be double, a condition it more nearly assumes further east, beyond the Ridge fault. Nearly a quarter of a mile east of Westhay Water is the little waterfall known as Ridge Water, which is in the trough of a syncline, since east of it the beds have a westerly dip. Rather less than 300 yards east of Ridge Water, the cliff ends abruptly in a big fault that lets the beds down about 100 feet* on the east. Between Ridge Water and this big fault are three little step-faults with a down- throw on the east of from 10 to 20 feet. They do not, however, 1 Described, Lang, GEOL. MaG., Dec. V, Vol. I, pp. 125, 126, 1904. It was visited by the Geologists’ Association in 1906, see Proc. Geol. Assoc., vol. xix, pt. ix, p. 323. ? The great undercliff on Stonebarrow, called ‘ Cain’s Folly’ on the six-inch Ordnance Survey map. I use the more familiar local name. * The Survey, following Day (Quart. Journ. Geol. Soc., vol. xix, p. 282, 1863), give a downthrow of only 40 feet (see H. B. Woodward, op. cit., 1911, p. 30) ; but considering that at this point the Red Band is reckoned at 45 feet above the Belemnite Stone, it must be about 95 feet above the beach on the west side of the fault, while it is beneath the beach 5 or 6 feet below the cliff-base on the east side of the fault; hence 100 feet is a fair minimum estimate of the down- throw. It is possible that there is a second fault a few yards further east, sharing the 100 ft. downthrow with the obvious fault, but this has not yet been definitely ascertained, and at any rate does not affect the present question. W.D. Lang—Lower Pluensbachian of Charmouth. 405 affect the position of the beds as a whole, since owing to their somewhat steep westerly dip these recover between successive faults the distance fallen (see Diagram I). The big Ridge fault brings down the Red Band from the rough ground above the Belemnite Stone to some feet under the beach and out of sight; but at about 50 yards east of the fault it rises from the beach (the dip here is still westerly) on to the low cliff, and in two 6in. bands about a foot apart, follows this cliff as it rises to some height eastwards, across St. Gabriel’s Mouth, and so well up on to Wear Cliff, Golden Cap. Here it is about 40 feet up the cliff, when the dip reverses, and it begins to descend again. The Belemnite Stone may be seen in the angle between the cliff and the beach beneath the western part of Wear Cliff; so at Golden Cap the Red Band is about 40 feet above the Belemnite Stone, whereas at Westhay Water there are 49 feet, at the western end of Stonebarrow only about 20 feet, and on Black Ven but 14 feet between them. The Lower Limestone, the second constant feature of these beds, is of very different appearance. Sharp, hard, nodular, and impersistent, it presents a marked contrast to the Red Band, which generally is seen in a soft, weathered condition, and occurs in continuous slabs rather than in discontinuous nodules. In spite of its nodular, impersistent nature, the Lower Limestone is remarkably constant in its appearance about half-way between the Belemnite Stone and the Red Band, and may be counted on with certainty in an appropriate section of some size, if it is looked for with care. Its characteristic fossils are ammonites of the Jatecosta group; it contains also Zrago- phylloceras loscombi (James Sowerby); occasionally, too, a Straparollus ; but fossils other than ammonites are rare in this rock. It occurs 7 feet above the Belemnite Stone on Black Ven; 10 feet at the western end of Stonebarrow Cliff; 21 feet at Westhay Water (where it is poorly developed and consequently difficult to find) ; and about 20 feet above the Belemnite Stone on-the western face of Golden Cap. After being thrown down by the Ridge fault, it can be picked up rising from the beach some forty yards east of the reappearing Red Band. The Upper Limestone is less easily found than the Red Band or the Lower Limestone. It appears half-way between the Red Band and the Lowest Tier. Like the Lower Limestone it is often sharp and nodular, but the nodules tend less to a spherical shape. On the western side of Stonebarrow, however, it is either flaggy and tends to be sandy like the Three Tiers, or is nodular and calcareous with a sandy shell; and it may change abruptly within a few yards from one to the other condition. The sandy beds mentioned in the Survey Memoir as occurring below the Three Tiers may be this rock, only they are comparatively higher in the Green Ammonite Beds Series. The Upper Limestone is above the highest Lias on Black Ven; but it may be found at the western end of Stonebarrow 35 feet above the Belemnite Stone or 15 feet below the lowest Tier. The ground, however, at this horizon is very broken on Stonebarrow, and it is not often that a section can be found in it. On the western side of Golden Cap, the Upper Limestone may be found 30 feet below the 406 W. D. Lang—Lower Pliensbachian of Charmouth. THREE TIERS. GREEN AMMONITE BEDS. a J Aimatltheus Ammoniles mmoniles cery SCarte. ja Alramont bs abundane. Gapricorn us AmnaniGs. Strialus Ammonites Qbundan€. Valdanz Almmaniles. ‘S: ¢ 8 % & g SF Ree ee Wes ere Sse “Ss . TS “SS eo OS Re i eS ee eS Ral z Re . Bo UNg ee tk ae Sp aR R y & ERY RRS, SSS ee See Sea AMHR MURTER EA mi it cu aa eh it i hie ny Na hi =ch i hl at i Heh ne zt i ii Hn Hi ae a iN iA A RAH AMR EHS AANA AMILE CAP. ys? >» Bm Oey on are WESTHAY A MULE WATER. an O84 2 lon 4 BLACK — |,88|az0ur |STONEBAR- VEN. |gn 1477/4. | ROW CLIFF, = ‘aa =—— =—— 43/2 F : Slap] — — ~ SERRE Ree CRETACEOUS CRETACESUS DIAGRAM II: DETAILED SECTIONS OF THE THREE TIERS AND GREEN AMMONITE BEDS, SHOWING THEIR VARYING THICKNESS AT DIFFERENT POINTS. W. D. Lang—Lower Pliensbachian of Charmouth. 407 lowest Tier, and about 70 feet above the beach. The only fossil common in this bed is Zragophylloceras losecombi (James Sowerby). Of the four clay masses included within the Green Ammonite Beds, the topmost, the Upper Clay, contains many capricornus-like © ammonites, and an Arca is fairly common, all in a filmy condition, and small pyritic casts of Zragophylloceras loscombi (James Sowerby). The second bed, the Upper Red-Band Clay, has similar fossils and in addition pyritic casts of ammonites of the becher and latecosta groups. The third, the Lower Red-Band Clay, in the upper part contains chiefly well-preserved 7. loscombt (James Sowerby) and, rarely, Deroceras dave (James Sowerby) in films, and, in the lower part, abundant Straparollus of two or three species, other small gastropods, young pyritized Z. loscombc (James Sowerby), and ammonites of the Jatecosta group. And the lowest bed, the Lower Clay, fossils similar to those in the lower part of the bed above. It should be clear from the above description that there is a con- siderable thinning of the Green Ammonite Beds as they pass westwards.’ In fact, at the western end of Stonebarrow their thickness is only half of what it is on the western side of Golden Cap; while on Black Ven, what remains of them gives evidence of further and proportional thinning. The variation is not, however, quite regular, since at Westhay Water the series appears to be slightly thicker than on the western face of Golden Cap. This diminution affects the whole series equally, so that the thickness of its subdivisions varies directly with that of the whole. Moreover, the Three Tiers share in the diminution, and may be seen on Stonebarrow shorn of half that development they display on Golden Cap.2 The lower two Tiers may be seen in place on Stonebarrow Cliff in the banks bordering the ereat hollow formed by a fall of the cliff (1908-9) beneath the beeches and pine-trees immediately west of Fairy Dell; and the Lowest Tier again on the cliff just west of this. The Lowest may be known from the two higher Tiers by being nearly twice as thick (in the same section) as either of these, and far more fosiliferous. Its chief fossils are ammonites of the margaritatus and loscombi groups and small gastropods. The Tiers are next seen about a hundred yards further east, at the western end of Fairy Dell, just east of the top of a big gully that makes it possible to climb the Belemnite Marls at this point. The gully is blocked in places by large masses of the Lowest Tier. In the section above it all three Tiers were to be seen in place and a few feet of Margaritatus Marls above them. The section, however, during the last year (1912-13) has foundered and is much obscured. The two higher Tiers with Margaritatus Marls above may be seen again beneath the junction of the Lias and Gault in the Lias bank that breaks through the overgrown expanse of Fairy Dell in its eastern part. It was conjectured in a former paper * that the base of the Cretaceous on Stonebarrow was at about 320 feet O.D. It now appears that this is at least 10 feet too high, and the actual heights-are probably 1 See GEOL. MAG., Dec. V, Vol. IX, p. 285, 1912. 2 See Grou. MAG., loc. cit., 1912. 3 Lang, GEOL. MAG., Dec. V, Vol. IV, p. 150, 1907. 408 W. D. Lang—Lower Pliensbachian of Charmouth. those given in the accompanying diagram. If these are right, the base of the Cretaceous on Stonebarrow is slightly lower than on, Black Ven, contrary to Jukes-Browne’s surmise. This does not, however, affect the validity of Jukes-Browne’s main argument.’ It remains to be seen if any correspondence can be established between the sequence given in this paper and the eight subdivisions of the Green Ammonite Beds in the Survey Memoirs. The detailed section given in the Memoirs? is about 100 feet thick, of which about one-half is occupied with the two lower divisions. It is safe, then, to assume that the five upper Survey divisions are above the Red Band. The upper three of these are remarkable for exhibiting sandy conditions like the Upper Limestone on parts of Stonebarrow ; but they include only 13 feet, whereas the Upper Clay on the west face of Golden Cap is 30 feet thick, and the Upper Limestone should therefore be found towards the bottom of the fourth subdivision of the Survey Memoir, the base of which is 33 feet below the lowest Tier. The ‘ferruginous band’, the fifth subdivision, is probably a streak of stained clay, since it is 30 feet above where the Red Band should appear. The sixth subdivision contains no hard beds; and the seventh, of indurated marl and limestone, is admittedly ‘occasional’ and probably, therefore, local, but might be meant for the Red Band. This leaves the eighth and lowest subdivision, measured with the seventh as 54 feet thick. By measurement this bottom 54 feet should include both the Red Band and the Lower Limestone. ‘The latter, presumably, is the ‘‘nodules of hard grey limestone’’, though there is nothing in the description that suggests that they are on one horizon; and the former the ‘ ferruginous bands’, though, even where the Red Band appears to be double, this would be a poor description of that rock. Thus, even if this interpretation is right, it cannot be said that a satisfactory correlation has been established between the two accounts. II. Tse Betemnire Marts. The Belemnite Marls* consist of some 80 feet of rock, capped by the Belemnite Stone and bounded beneath by a limestone containing ammonites of the armatus group. The Survey assign the Marls to the zones of armatus, jamesont, and ibex,* but do not suggest any lines of demarcation; on the contrary, they speak of ‘‘an inosculation of the zones’’.® Six subdivisions are given, however, based on the lithic characters of the beds. In practice it is not easy to be sure of these subdivisions, and the following are suggested as easier to recognize in the field (see Diagram ILI, p. 409): (1) a lower division, about 40 feet thick, of darker marls—the Lower Marls; (2) a middle division, about 28 feet thick, of paler marls—the Middle Marls; and 1 This concerns the general shape of the Cretaceous base-line in this district, see Jukes-Browne, Proc. Dorset Nat. Hist. Club, vol. xviii, p. 176, 1897; and GEOL. MAG., Dec. IV, Vol. V, p. 164, 1898. ? The most detailed account is in H. B. Woodward, op. cit., 1893, p. 69. * The Stonebarrow or Belemnite Beds of the Survey Memoirs. 4 H. B. Woodward, op. cit., 1893, p. 67. * H. B. Woodward, op. cit., 1893, p. 68. W. D. Lang—Lower Pliensbachian of Charmouth, 409 Green Ammonile Beds. Ss PSS Belemnile Stone. = Pyrilic marls Va =| Belomnile shales. Upper darker mars. st — = SEG Soe Soper pale bard. APO LINE A aa Gx ee Gronnz ammoniles lowards lp. =| riddle dark band. =| Middle pale band. == Joppa CpG ARE Lower darker marls. Lower poler marés. Armalus Gmesione. Raricostalus Beds. ni ammonites. PLIDDLE MARLS. LOWER MARLS, UPPER MZARLS. ryaldarz-tbex Zone, ? Jarmesont 2ORe. ? pellos zone, I) EE Parmalus zone DIAGRAM III: DETAILED SECTION OF THE BELEMNITE MARLS. 410 W. D. Lang—Lower Pliensbachian of Charmouth. (3) the Upper Marls, on the whole darker than the Middle Marls, about 16 feet thick. The Lower Marls have at their base the Armatus Limestone just mentioned. This rock is rarely exposed on Black Ven and on the western end of Stonebarrow, being generally covered with talus; but it is well shown at the base of the eastern part of Stonebarrow Cliff where it comes down to the beach about a mile east of the mouth of the Char; andit forms a long ledge under the shingle bank between the tide-marks still further east, that is more or less exposed according to the accidents of wave and shingle. It is the home of the ‘large examples of this Ammonite [ Deroceras armatum | with prominent spines”’ whose ‘‘ particular horizon requires investigation”? of the Survey Memoir.’ The ammonites are poorly preserved, being represented only by a black film, and, since the matrix is comparatively hard, they are difficult to extract satisfactorily. The Armatus Limestone lies a foot or two above the Watch Ammonite Stone (the ‘‘ Grey, earthy limestone” of the 1893 Memoir, and part of the ‘‘ Watch-stone Beds” of the later Memoirs), a characteristic Limestone often crowded with Ammonites of the raricostatus group. At the base of the Lower Marls, and extending to within a foot of the Armatus Limestone, are one or two pale bands that look like Limestone. ‘hey can hardly, however, rank as such, being merely indurated marls, and, although highly calcareous, are quite soft compared with the Armatus Limestone. In fact, there is no definite bed from the Armatus Limestone up to the Belemnite Stone that is anything more than an indurated marl. If these are the ‘‘ marly limestones and shales” constituting the last two subdivisions of the Belemnite Marls in the Survey Memoirs, the Armatus Limestone is not there recognized? It is better, however, to regard these lowest two subdivisions as including the Armatus Limestone and the pale indurated marls above. These pale indurated marls at the base of the Lower Marls must have some wave-resisting quality in spite of their comparative softness, for they form the shoal called Hawkfish Ledge that les just off Westhay Water. Owing to the change of the dip here from an easterly direction to nearly horizontal, this ledge, instead of running out seawards at a small angle with the coast, swings round festoon-wise, enclosing a minute roadstead at half-tide. The Armatus Limestone does not appear to form part of Hawkfish Ledge, but makes a reef running seawards of it. Except for the lowest few feet the Lower Marls are dark as a whole and comparatively barren. They yield belemnites and saurian remains, and, at the top, the same Jnoceramus as the Middle Marls. If, as is possible, the Middle Marls represent the jameson zone, it is likely that the rare examples of A. pettos that have been found beneath Stonebarrow Cliff come from the Lower Marls. The Middle Marls consist of three thicker pale and three thinner dark bands. The pale bands are very fossiliferous in places, though 1 Woodward & Ussher, op. cit., 1911, p. 30. * The Survey follow Day in calling these indurated marls, limestones; see Day, Quart. Journ. Geol. Soc., vol. xix, p. 281, 1863. On p. 280, however, Day speaks of ‘‘semi-indurated limestone ’’, which is a far less misleading description. W. D. Lang—Lower Pliensbachian of Charmouth. 411 the fossils for the most part are poorly preserved, and are not easy to find in place, however they may abound in fallen blocks. he commonest fossil is Znoceramus falgert, Merian in Escher von der Linth,! a large form described from Lias above the Sinemurian of Lechthal, N.E. Switzerland. Several species of Ammonite have been found, but await identification. Since different horizons have yielded different kinds, it is hoped that if the species can be determined, it will be possible to draw zonal lines in this middle division with some exactness. Belemnites are common throughout. The bottom division—the Lower Pale Band—itself is sometimes divided by three still paler beds. It comes to the beach at Ridge Water, and owing to the reversal of the dip at this point rises on to the cliff on each side. It is thrice thrown down again on the east by the small step-faults already mentioned (p. 404) between Ridge Water and the big Ridge fault. The Middle Pale Band is easily recognized by being always divided by three paler beds and two intervening darker beds into five stripes. This feature is constant throughout the whole of its exposure from the western side of Black Ven to the Ridge fault; whereas the Lower Pale Band is only sometimes thus divided, and the Upper Pale Band, if differentiated at all, breaks up into a large number of beds. The Upper Pale Band is the thickest of the three, 8 feet as compared with 5 and 4 feet respectively for the Lower and Middle Pale Bands. It becomes somewhat darker in its upper part, and tends to pass into the Upper Dark Band. In its top portion it contains Uptonia aff. bronnt (Roemer).? At about three- quarters of a mile east of the mouth of the Char, the Upper Pale Band is seen to split into about sixteen alternating lighter and darker stripes, but generally it is more or less uniformly pale. The Upper Marls on the whole are dark. ‘The bottom bed, how- ever, a 2ft. pale band, is conspicuously contrasted to the 1 ft. Upper Dark Band of the Middle Marls, and with it forms a convenient because easily recognized division between the Upper and Middle Marls. Above the 2ft. pale band are 8 feet of darker marls, then 3 feet of dark Belemnite Shales, and finally 3 feet of marl with much pyrites capped with the Belemnite Stone. ‘he 3 feet of Pyritic Marl are almost certainly the beds whence have come ammonites of the valdani group,? preserved in pyrites, that are not uncommonly found on the terrace below the Belemnite Marls. So far but one of these has been found by the author in place—1 foot below the Belemnite Stone. It is probable, then, that the line between the jamesoni and tbex-valdani zones will be drawn in the lower part 1 A. Escher von der Linth, ‘‘ Geol. Bemerkungen u. d. nérdliche Vorarlberg und einige angrenzenden Gegenden,’’ 1853, p. 1, pl. i, figs. 1-5. See also W. Ooster, in C. von Fischer-Ooster, ‘‘ Protozoe Helvetica,’’ vol. i, pf. ii, pl. xii, figs. 1-5, pp. 36, 37, 1869. Iam indebted to my colleague, Mr. R. B. Newton, for kindly identifying this form. 2 The following additional note was added by Mr. S. S. Buckman, who kindly identified this form: ‘‘?=youngof d’Orbigny’s large figure of Uptonia regnardi,’”’ d’?Orbigny, 1842, Pal. Franc. Terr. Jur., p. 257, pl. lxxii, fig. 1. 3 Mr. §. S. Buckman has kindly examined this form and identified it with Acanthopleuroceras ellipticum (James Sowerby), ‘‘ very near to A. valdant.”’ 412 W. D. Lang—Lower Pliensbachian of Charmouth. of the Upper Marls. The Survey Memoir mentions “ nodules and impersistent masses of hard grey limestone within two feet of [ below ] the Belemnite Stone”.’ At about this horizon, at Westhay Water, and forming a shelf at the top of the waterfall, is a lenticular bed of Limestone, 1 to 2 inches thick, largely composed of Crinoid remains. The Belemnite Marls do not vary much in thickness, as a whole, from their appearance on the western shoulder of Black Ven to their disappearance beneath the beach east of the big Ridge fault; they vary a good deal, however, in the thickness and hardness of individual pale beds, which is probably due to the amount of segregation of calcium carbonate that has taken place; the thicker and paler the bed, the harder and more calcareous it appears. The limestones throughout the Charmouth Lias appear to be of the nature of segre- gations ; the most complete having the form of nodules, like those of the Stellaris Beds? and the Lower Limestone of the Green Ammonite Beds*; the less complete being muddy limestones like those of the bucklandi zone (the Birehit Bed* is an example of a limestone now nodular, now tabular) ; the still less complete being indurated marls like those under discussion. Table Ledge‘ is a transition from an indurated marl to a muddy limestone. Kast of the Ridge fault the Belemnite Stone rises to the foot of the cliff about a quarter of a mile east of St. Gabriel’s Mouth, but soon plunges under the beach again, reappearing once more between Golden Cap and Seatown.® And the Upper Marls are exposed between the tide-marks under Golden Cap.°® It has been suggested that the Armatus Limestone and the indurated marls just above it are included in the two bottom beds of the six subdivisions made by the Survey in the Belemnite Marls. The third division from the bottém probably represents the rest of the Lower Marls, and the fourth division the Lower Pale Band of this paper. The fifth, then, would include the rest of the Middle Marls and all except the top 6 feet of the Upper Marls; and the top division, the Belemnite Shales and the Pyritic Marls. At any rate this correlation is more satisfactory than that attempted for the Green Ammonite Beds. Finally, I would express my thanks, first to my wife for much help in the field; also to Mr. Thomas Hunter, fisherman, of Charmouth, who has known these cliffs from boyhood and helped EK. C. H. Day who first worked them in detail, and for some years from time to time has given me much useful information and advice; and to Mr. L. Spath, F.G.S., for advice in connexion with the ammonites mentioned in the paper; as well as to Mr. 8. S. Buckman, F.G.S., and Mr. R. B. Newton, F.G.S., whose help in each case has been indicated in the text of the paper. H. B. Woodward, op. cit., 1893, p. 68. H. B. Woodward, op. cit., 1893, p. 65, ‘* Am. stellavis in nodules.”’ See ante, pp. 401-2. H. B. Woodward, op. cit., 1893, p. 60. H. B. Woodward, op. cit., 1893, p. 52. H. B. Woodward, op. cit., 1898, p. 66. an fF oOo wo eH Mojor A. J. Peile—Notes on the Bermuda Islands, 418 V.—Nores oN THE GroLoGy oF THE Bermupa ISLANDS. By Major A. J. PEILE, R.A. Il, N a very interesting article on the Geology of Bermuda, published in this Magazine for September and October, 1911 (pp. 885-95 and 433-42, Pls. XVIII-X XIII), the late Rev. R. Ashington Bullen states, on p. 390, that Admiral’s Cave at Spanish Point is in the Walsingham Formation. This statement is evidently due to a slip in map-reading, Admiralty Cove being the boat harbour of Admiralty House near Spanish Point, whereas the Admiral’s Cave, whence the Pecilozonites nelsoni in the British Museum were derived, is the ‘¢ cave near the calabash-tree ’’ mentioned on p.439. This cave owes its name to the visit of Admiral Milne, and the base of his stalagmite is still in evidence, bearing his tool marks. It is one of the largest and most remarkable of the many caves between Bailey’s Bay and Tuckerstown. With regard to the connexion between these shells and the formation in which they occur, P. nelsoni is found in great quantity, associated with afew other species, in a bed of earth far within the cave. It is probable that the earth was washed into the cave through some fissure when the rainfall in the islands was greater than it is at present. It is, however, noteworthy that the shells, which are well coated with a stalagmitic (?) deposit, do not as a rule contain earth. Traces of animal matter have been found in the inner whorls of some of them, and broken specimens often exhibit colour-bands resembling those of the living, but much‘smaller, P. bermudensis and its extinct variety, P. zonatus. In fact, the circumstances under which they are found here and in other caves! make it unlikely that the shells are contemporaneous with the rocks in which the caves are formed. P. nelsoni is also to be found in hard rock, and so are other species, some of which are extinct. . In many cases the shells had evidently found their way into crannies in the rock, where they were later cemented in by stalagmitic deposits (vzde diagram, p. 390). In other cases they appear to be regularly embedded in the mass of the limestone. It is probable that the variations in character of the eolian sandstone, due to chemical deposits from infiltered water, are not always an index of the age of the rock, so that it is just possible that the presence of these shells does not definitely determine a deposit as belonging to the Walsingham Formation, as suggested on p. 390. It is interesting to note that the small neck of land between Castle Harbour and Harrington Sound, which is honeycombed with eaves containing fossil shells, and which differs somewhat in the character of its vegetation from the rest of the islands,” is perhaps the only present habitat of two of the species of endemic snails that flourished along with P. nelsoni. These are P. reinianus and P. gooder. Living examples of these two species are hard to come by, but it is 1 The first P. nelsoni recorded were found by Lieut. Nelson in a cave at Ireland Island, at the other end of the islands. 2 Tt is sometimes said to be a bit of surviving jungle of the ancient Bermuda. 414 Rev. Dr. Irving—Old River-Valley near Peterborough. a suggestive fact that their dead shells may be found in large numbers in crannies in the rocks. The fossil specimens from some localities, but not from others, are larger than the living forms. Two other living species, P. bermudensis and P. circumfirmatus, are more widely distributed and are fairly common. A most interesting account of the fossil land shells, by Professor Addison Gulick, is to be found in the Proceedings of the Academy of Natural Science of Philadelphia for July, 1904. There is still work to be done in the study of the varieties of fossil species from different localities and in tracing the connexion between the fossil and living forms. ING The analysis of the phosphorite rock, described at the end of the article, suggests an interesting problem. Flat bottoms among the reefs, at any rate in the more sheltered channels and sounds, consist of chalky mud, reduced to its present state in the intestines of the big holothurians, known locally as ‘sea cucumbers’. It is possible that a similar origin for the rocks analysed would account for their coprolitic nature. ‘The question of how such an ancient sea bottom came into its present position would still have to be tackled, but the theory now suggested seems at least more tenable than that of deep sea mud referred to as impossible on p. 440. Although there is every proof that the islands have been sinking during past ages, there have been some slight upheavals, if only local, as evidenced by the so-called Devonshire formations containing marine shells (vide p. 393). VI.—Nore on a Buriep (East Mercian)’ River CHANNEL NEAR PETERBOROUGH. By A. Irvine, D.Sce., B.A. N the Peterborough Advertiser for December 16, 1911, there appeared an illustrated article on a ‘‘recent discovery” of a silted-up pre-glacial river-valley, 250 yards wide, at Fletton, near Peterborough. Eliminating from that article a good deal of scientific romance, there remains a certain residuum of geological facts, so far as the determination of them by the writer of this note has been carried out, through the courtesy of Mr. A. Adams, the Manager of the London Brick Company’s works. The banks of the ancient river appear to be well defined on the north and south sides of the buried channel. Against these there lies a deposit of slimy river-silt derived from the material of the Oxford Clay, through which the river (comparable with the Trent at Newark) had carved out its course. This black silt contains fossils of the Oxford Clay itself, along with shells of Cardium edule*, and 1 Read at the British Association, Dundee Meeting (1912), Section C. 2 Determined by Mr. R. B. Newton at the British Museum (Nat. Hist.). Mr. G. Wyman Abbott, of Peterborough, is preparing a paper on the shell- contents of these beds in co-operation with a well-known specialist on recent shells. Rev. Dr. Irving—Old River-Valley near Peterborough. 415 considerable masses of lignite, but apparently no boulders. It appears to be of local origin. Its junction with the Oxford Clay in situ is seen, in open sections on both sides of the channel, while upwards it is mixed up with the fine stratified river-gravel and sand, which (as interglacial or ‘subglacial’’ deposits) seem by the evidence of well-sections to have filled the pre-glacial, valley, as such deposits have filled the pre-glacial valley of the Stort.? In composition these gravels (so far as examined) agree remarkably with those at Stansted Mountfichet and other places in the upper Stort valley, and like them contain rolled Belemnites, Grypheas, etc., from the Jurassic rocks. In other respects the gravels have also much in common with the high-level stratified gravels of the Trent at Beeston,? where the Jurassic fossils seem to be wanting. In open sections on both sides of the channel these gravels are, in their upper portions, puckered and distorted apparently by frozen masses of gravel of the floating-ice stage of glaciation, agreeing with the facts observed in the upper Stort valley * and in the old Windsor Forest country of the Thames outer valley ° in East Berks. The facts observed, as recorded in this and previous papers, taken together with the known physiography of the upper Trent basin, seem to suggest inferentially a connexion in late Tertiary times between that and the Thames Valley by way of the buried channel through the Chalk Range *®; the capture of the Trent by the Humber being accounted for by crustal movements and by the glacial damming, of which the 90 feet of Boulder-clay furnishes evidence, as this was observed years ago by Dr. J. J. Harris Teall and myself, when the Midland Railway from Melton Mowbray to Nottingham was in process of construction. The River Nene above Peterborough appears to cut right across the buried channel, indicating the comparative modernity of the present river-system of the Wash Basin. % % % ¥ # My more recent work during the month of August (availing myself of the local knowledge of Mr. G. Wyman Abbott of Peterborough) has led me to conclude—from observations made in the sand and eravel pits known as Anker’s Pit and Rippon’s Pit (both close to Peterborough) and in London Brick Company’s Pit No. 1 at Old Fletton—that the relations of the Nene Valley to the ancient buried channel are not so simple as appears at first sight. In the silted-up Nene Valley, however, the succession of the deposits is roughly as follows :—’ 1 N. O. Holst. 2 A. Irving, B.A. Reports for 1910, 1911. 3 A. Irving, P.G.A., vol. xv, p. 232, 1898. 4 Op. cit., vol. xv, pp. 224, 225. Also Report of Excursion to Bishop’s Stortford (1911): op. cit., vol. xxii, pp. 264 ff. 5 Op. cit.: Excursion to Wokingham and Wellington College in 1890, with photograph of one of the sections, now obliterated and overgrown. Similar photographs presented at the time to this Association, and one was published in Science Gossip. 8 See B.A. Report, 1910 (Section C), p. 616. 7 [Pre-glacial valleys in Northamptonshire have been described by Mr. Beeby Thompson, Journ. Northants Nat. Hist. Soc., ix, p. 47, 1896, and xii, p. 207, 1904.—ED.] 416 J. Reid Moir—Striations wpon Flint. ANKER’S PIT. 1. Gravelly loam. Post-GLaAciAL | 2. False-bedded sand. SERIES 3. Stratified gravel. 4. Clay, 2 to 48 inches. ( 5. Gravel (late-glacial) and clay containing GLACIAL paleoliths and remains of horse and (PLEISTOCENE) i of Hlephas primigenius with erratics. 6. Stratified gravel with erratics. 7. Oxford Clay. The deposits seen in Rippon’s Pit may, I think, be taken as the equivalents of the upper three or four beds in Anker’s Pit, while the lower series (5, 6) would seem to represent the succession in the pits of the London Brick Company, Nos. 1 and 4. There is much **contemporaneous erosion and filling-up’’’ in Rippon’s Pit. At No. 1 Pit (Old Fletton) the stratified fine sandy gravel is seen in open section extending down to the depth of 25 feet in the old channel and resting upon probably reconstructed Oxford Clay. Like the same gravels at No. 4 Pit, it contains erratics of con- siderable size, so that they would both seem to be sub-glacial, and to represent the ‘ice-raft’ stage of the later glaciation of the district. At both places they yield mammalian remains (including E. primigenius), and have the same character in structure and composition as that given above in detail for the No. 4 Pit. It is, however, a noteworthy fact that at the latter place they overlap the bank of the pre-glacial valley, with a deposit 8 or 9 feet thick, indicating the widespread shallow-water conditions of the later ice-raft stages of glaciation. That they are of later date than the great Chalky Boulder-clay is evident from the fact that a ridge of high ground some miles in length, to the south-east, consists of that deposit, in which I recognized erratics from the Chalk, the Lias, and the Carboniferous Limestone, when I visited it in company with Mr. Abbott, to whose courteous guidance over the district | am much indebted. VII.—Tur ‘ WEATHERING oUT’ OF STRIATIONS UPON FLINT. By J: Rem Morr, F.G.S. OR some time past I have had a difficulty in understanding how certain striated flints from various horizons stood, without breaking, the pressure to which they must have been subjected when such markings were imposed upon them. This difficulty increased when I found that thin flakes from the present land surface exhibited well-marked striae, and as experiments with my presses had shown that even large flints will break up under no very great pressure, the possibility occurred to me of these scratches having altered since the flints were first subjected to the scratching process. I reasoned that if a point passed over a flint under pressure the area upon which the point impinged would be shattered, and that small plates or splinters of flint would be formed along the line of movement. I also concluded that, as with the thin plates which 1 A term used long ago by F. B. Jukes. Notices of Memoirs—H. B. Maufe—S. Rhodesia. 417 are produced on a flint when flaking, and which are not found upon implements which have been exposed to atmospheric conditions, these fragments would in time, by thermal effects, ‘weather out’ and leave a clean-cut groove behind. When I proceeded to test my theory by examining a series of striated flints in my collection I found various specimens which seem to me to show strie in different stages of weathering. Thus one black glossy flint given me by Mr. HK. St. H. Lingwood, of Westleton, Suffolk, and found by him on a ploughed field at that place, showed a shattered scratch extending for about 14 inches across its surface. To prove that such a scratch “could easil y be deepened I attacked part of it with a steel probe and found that I could easily remove the thin plates of flint which were produced when the initial shattering took place. I then took a pointed flint flake and cleared away the remaining splinters of flint in the groove I had made, and this specimen, therefore, now exhibits a shattered line over half its length, and the other half a deepish groove. This question of the ‘ weathering out’ of scratches appears to me to be of some importance, because what we have looked upon as deep strize caused by great pressure are in all probability merely ‘ weathered out’ scratches, the initial stage of which would not require any very great pressure to produce. I give it as my opinion that every scratch imprinted upon a flint must have a shattered portion on the sides and floor of the scratch, and, further, this shattered portion, if exposed long enough to thermal effects, must ‘ weather out’ and the scratch alter in depth and appearance until all the thin fragments are gone. If a flint gets striated, and then becomes covered by some impervious material such as clay, then it will be protected from thermal changes and no ‘ weathering out’ of the scratches take place. This perhaps offers an explanation for the smallness of the strie on the flints from the Chalky Boulder-clay, as compared with those showing on stones from below the Red Crag. The latter were scratched and then exposed on the pre-Crag land surface, and consequently got ‘ weathered out’, while those in the Boulder-clay have been protected by the nature of the material in which they lie, and many of them exhibit typical unweathered out, shattered, scratches. In this note I refer solely to the strize which are developed upon the hard portion of the flints, not to those upon the softer cortex. NOTICHS OF MEMOTRS.- a GrotocicaL Survey or SourHERN RHopDEsIA. (J\HE following is an abridged statement from the Report of the Director, Mr. H. B. Maufe, for the year 1912 (fol. ; Salisbury, Rhodesia, 1913): As a result of the detailed work amongst the metamorphic rocks, it is becoming increasingly clear that they are divisible into three series, one of which consists of three groups: (a) a greenstone schist group, including epidiorite, (2) a banded iron-_ stone group, and(c)a conglomerate and grit group. The second series consists of ultra-basic rocks, some of which contain chromite and asbestos. The third series comprises a very variable group of fine- erained and frequently schistose acid rocks, which have not hitherto DECADE V.—VOL. X.—NO. IX. 27 418 Reviews—Dr. F. A. Bather—Cystideans from Girvan. been recognized as a distinct series. Moreover, a consideration of the distribution of gold-bearing quartz reefs and the mode of occurrence of an important class of auriferous impregnations has led up to what is probably the point of greatest practical importance resulting from the year’s work, namely, that the gold deposits of the Territory are closely associated with the last-named series of acid igneous rocks. The north-western portion of the Wankie coal-field, including the main basin in which the colliery is situated, has been mapped by Mr. Lightfoot, whose geological work has determined the succession of rocks and the structure of this field. The discovery of fossil plants is interesting, as proving what perhaps was never seriously doubted by geologists, that the Wankie coal-beds belong to the lower part of the Karoo system. The main coal-seam is known to be a very thick one, and the best in the sub-continent for steam-raising purposes. The survey of the district now shows that the basin in which the colliery is situated, although bounded in parts by-faults, is simple in structure, and remarkably free from faults and other disturbances. Estimates of the resources of the field made previous to the survey showed a very large reserve. Not only is this now confirmed, but a large addition may be made with considerable confidence. Mr. Lightfoot points out that probably 600,000,000 tons of coal could be taken out of the district mapped by him. Investigations were made, partly in conjunction with the Chemist to the Agricultural Department, into a number of deposits of limestone and clay, with special reference to their suitability for the manufacture of Portland cement; and a syndicate has proved by trial tests that such a cement, exceeding the requirements of the revised British standard specification in strength, etc., can be made out of materials occurring near Bulawayo, and that a sufficient quantity of them is available. Observations on the relation of the soil, or more accurately the subsoil, to the underlying rocks have resulted in the collection of a considerable amount of evidence showing that the soils are largely residual accumulations, and that two of the most important factors in determining their character are (1) the nature of the underlying rocks, and (2) the behaviour of the soil-water. REHEVLINWS- ie Aaa I.—Carapocran CystrpeA FRoM Girvan. By F. A. Barner, M.A., D.Se., F.R.S. Trans. Roy. Soc. Edinburgh, vol. xlix, pt. ii, No. 6. 4to; pp. 359-530, with 6 plates and 80 text-figures. Edinburgh: Robert Grant and Son, 107 Princes Street, 1918. Price 15s. 6d. (PLATE XIII.) F we examine the various members in almost any grade of the Animal Kingdom we shall meet with some so unlike, superficially, our conception of the type, as to cause us, at first sight, to doubt their right to a place in the phylum to which they have been assigned by the systematist. But a careful study of the larval stages of develop- ment of many such erratic forms has usually led to the recognition of their true position. It is within the memory of the writer that Lepas anatifera was arranged with the Mollusca in the Shell Reviews—Dr. F. A. Bather—Cystideans from Girvan. 419 Gallery of the British Museum, and, at a much later date, the Brachiopoda and the Tunicata (1851-6) were still retained in textbooks in the same phylum, as a part of the Malacostraca. As paleozoologists we are much indebted to Dr. F. A. Bather for having undertaken the study of the Echinoderma, of which he says it is ‘‘one of the best characterized and most distinct Phyla of the Animal Kingdom”. Notwithstanding this encouraging introduction, we venture to think that this division contains many very difficult organisms to investigate, to which the author has devoted long years of careful and diligent study and made extensive acquaintance with both the literature of the subject and the specimens to be described. Particularly we must thank him for that admirable volume in 1900 on the Echinoderma.! In it Dr. Bather writes: ‘‘ Nearly all the living animals included in this phylum, such as the sea-urchin (Echinoid), starfish (Asteroid), brittle-star (Ophiuroid), sea-cucumber (Holothurian), and sea-lily (stalked Crinoid), or feather-star (free Crinoid), can readily be distinguished through their possession of a radial symmetry, in which the number five is dominant; of a sub- epidermic skeleton composed of calcium carbonate with a characteristic micro-structure resembling trellis-work, and of a system of sacs, canals, and tubes that carry water through the body, especially by means of five radial canals from which small branches called podva: are given off to the exterior. The extinct forms known as Blastoidea and Edrioasteroidea appear to have had a similar organisation, and the same statement may be made of most of the Cystidea’’—the class. which forms the subject of the present monograph. In this his latest work the author presents us with a description of the Cystidea (one of the three extinct and most aberrant classes of the Echinoderms), collected from the Caradoc Beds (Ordovician) of Girvan, Ayrshire, by Mrs. Robert Gray, who has done so much to add to our knowledge of the fossils of this now historic locality. In this undertaking she has been fortunate in having had the co-operation of various paleontologists, including the late Professor H. A. Nicholson, Mr. Robert Etheridge, jun., Mr. F. R. Cowper Reed, Dr. F. A. Bather, and others. e Though written ”’ (says Dr. Bather) ‘‘in order to describe Girvan material, the memoir has grown to be little less than a monograph of the genera dealt with, and even includes the description of a new species from Bohemia. For this no apology is required. When a group of organisms has recently received adequate revision, new forms may on occasion be merely described and referred to their systematic position. In the present instance, prolonged study of allied species and genera proved a necessary preliminary to the understanding of the Girvan fossils, and if the descriptions of the latter are to be intelligible the reader must first be placed at the same point of view as the writer.” To show the geological distribution in Girvan of all the Cystid remains, both described and undescribed, the author adapts a portion 1 Contributed to Sir E. Ray Lankester’s Treatise of Zoology (assisted by Dr. J. W. Gregory and E. S. Goodrich), 8vo, 1900, pt. iii, pp. vilit+344, and 309 text-figures. 420 Reviews—Dr. F. A. Bather—Cystideans from Girvan. of the Table of Girvan Strata drawn up by Messrs. Peach, Horne, and Macconochie (1901).' LLANDOVERY—NEWLANDS SERIES. 3. CAMREGAN GROUP. Bargany Pond Burn. Plate of a Grits, limestones, and shales. Glyptocystidean (?). Rastrites maxumnus. 2. SaucH HILL Group. - Woodland Point. One plate and one Flagstones and shales. base (?) of a Cystid (?). Monograptus spinigerus. Rastrites peregrinus. 1. MuLiLocH HitL GROUP. Sandstones and shales; con- glomerate. Diplograptus acuminatus. « CARADOCIAN—ARDMILLAN SERIES. 5. DRUMMUCK GROUP. Thraive Glen. Species of Dendro- Mudstones, Starfish Bed. cystis, Cothurnocystis, Cheirocruuus, Dicellograptus anceps. Pleurocystis. 4, BARREN FLAGSTONE GROUP. Diplograptus truncatus. ; , 3. WHITEHOUSE GROUP. Shallock Mill. Plates suggestive of Dicellograptus complanatus. Echinoencrinus. Pleurograptus linearis. ARDWELL GROUP. Flagstones and shales. Climacograptus caudatus. bo 1. BALCLATCHIE GROUP. Ardmillan ; a Glyptocystid (? Cheiro- Conglomerate, mudstones. crinus) and plates a and B. Bal- Climacograptus bicornis. clatchie ; plates 8B (y=Glyptocys- tidean) and ¢ (=Echinospherid). Dow Hill; plates 5 and e, plates of Cheirocr. (?), and fragments indett. The Starfish Bed, as its name implies, is prolific in Echinoderms. In addition to Zetraster Wyville-Thomsont there are many Asteroidea, now being studied by Mr. W. K. Spencer. Though the Cystidea of the Starfish Bed are numerous in individuals, the number of species is small. Dr. Bather describes only nine species, of which eight are new, and it is, he thinks, quite possible that some future paleontologist will say these are twice as many as they ought to be. The genera represented are— AMPHORIDEA HETEROSTELEA— RHOMBIFERA— Fam. Dendrocystide. Super-fam. Glyptocystide. Dendrocystis. 1 sp. Fam. Cheirocrinide. Fam. Cothurnocystide. Chewrocrinus. 2 spp. Cothurnocystis, n.g. 2 spp. | Pleurocystis. 4 spp. The Amphoridea among the extinct Cystidea are defined by the author (p. 364) as ‘‘ Primitive Cystidea in which radial symmetry has affected neither food-grooves, nor thecal plates, nor (probably) nerves, ambulacral vessels, nor gonads”’. In fact, they are most irregular forms of Echinoderma, and might well be styled as the ‘Nonconformists’ of their order, of which RAipidocystis is an example 1 “The Silurian Rocks in the South of Scotland’’ in Fauna, Flora, and Geology of the Clyde Area, Brit. Assoc. Glasgow, pp. 423-44. 4 Reviews—Dr. F. A. Bather—Cystideans from Girvan, 421 (see p. 869, figs. 1-8, and p. 370, fig. 4) from the Ordovician of St. Petersburg. Here are also placed the species of Dendrocystis— Described as having ‘‘a theca broader towards the column and composed of numerous plates irregular in size, form, and arrangement, the vent lateral and adcolumnal, the intake lateral and a-columnal and connected with a single skeletal process composed of four series of ossicles, with a stem proximally widening and composed of small widened ossicles, distally sub-cylindrical, gently tapering, and composed of elongate dimeres, and intermediately of transitional composition’. (p. 369 We reproduce one example, namely, Dendrocystis scotica, Bather, sp. nov., Plate XIII, Fig. 3. Altogether five species are enumerated, namely— D. scotica, F. Bather, sp. nov. Upper Caradocian: Thraive Glen, Girvan. Op. cit., p. 374, fig. 9; p. 391, pl. i, figs. 10-25. D. Sedgwickw, J. Barrande. Zahorzan, Bohemia. Lower Caradocian : Girvan. Op. cit., p. 374, fig. 8; p. 387, pl. i, figs. 5-9. D. paradoxica, H. Billings. Trenton Limestone: Quebec. Op. cit., p. 397, text-fig. 13; p. 396. D. rossica, O. Jaekel. Upper Liandeilian: EHsthland. Op. cit., p. 396, text-figs. 10-12. D. Barrande, F. A. Bather, sp. nov. Lower Llandeilian: Bohemia. Op. cit., p. 383, pl. i, figs. 1-4; p. 374, text-figs. 6, 7. The next remarkable form from Girvan is referred to a new genus, Cothurnocystis, of which two species are named: C. Hlza, F. A. Bather, gen. et sp. nov.,' and C. curvata,? F. A. Bather, sp. nov. Drummock Group, Starfish Bed:-Thraive Glen, Girvan. Cothurnocystis,? so named by the author from the outline of the frame being markedly boot-shaped, has its integumentary plates normally flat and tessellate, with subvective grooves of elliptical outline, occupying an area immediately adjacent and parallel to the curve of the boot sole (Plate XIII, Fig. 1). On Plate XIII we give two figures, the obverse (Fig. 1) and reverse (Fig. 2) of one species, C. Elz, so named in honour of _ Mrs. Elizabeth Gray, to commemorate her zeal in collecting so rich a series, and her acumen in recognizing the peculiar shape and the Cystid nature of these extraordinary fossils. They were obtained from the Starfish Bed, Girvan. (p. 400.) ‘«This creature” (says Dr. Bather),‘‘ though plainly a Pelmatozoon, is so different in structure and outward form from any other Pelmato- zoon as yet known that it is by no means easy to discover its true affinities. The very fact of this difference points to the conclusion that the animal was modified for some unusual habit of life; and our first task must be . . . to reconstruct from the dry bones the living organism.”’ He then proceeds to describe the position of the vent, situated between two spines on the dorsal surface (‘‘ described as the leg of the boot’). ‘* A vent of this nature implies a gut and a corresponding intake.” (p. 413.) After careful study and comparison with other forms, the author concludes that Cothurnocystis must have obtained its food by 1 Op. cit., pp. 398-408, pl. iii, figs. 26-38, text-figs. 14-23. 2 Op. cit., pp. 408-12, pl. iv, figs. 39-45, text-figs. 24-28. 5 From dGopvos (cothurnus), a high Grecian shoe, the foot-covering of tragic actors. 422 Reviews—Dr. F. A. Bather—Cystideans from Girvan. a subvective system of ciliated grooves,’ and he shows that each of the elliptical organs was in part such a groove; that the rim is divided at about two-thirds the distance from its outer end into an inner short U and an outer Jong U, meeting by their free ends. The opening of the larger U was roofed in by an alternating series of movable cover-plates, and the opening of the short U was protected by its own bounding wall so as to form a hood which on occasion could meet the closed cover-plates, and so shut the whole opening. ‘‘ Every known Echinoderm with a stem is a Pelmatozoon, and as such obtains its food by a subvective system of ciliated grooves, there is therefore no reason to suppose that in this respect Cothurnocystis was any exception. . . . When in full swing the cover-plates were open, the tentacles or podia were fully protruded, and a stream of sea-water was driven down each of the fifteen or more grooves, and diverted by the hood of the short U through the round mouth. Then if some passing animal brushed against a tentacle, the podia were quickly retracted, all the cover-plates shut down, and the hoods pulled up against them so as to close the mouths.”’ (p. 415.) In what position did Cothurnocystis live? There is no trace of a root or of any means of attachment, and it is probable that the stem after gradually tapering was rounded off abruptly, and did not fix it in any way. The position of both intake and vent are on the obverse face; we may conclude, therefore, that the reverse face was directed towards the sea-floor. The extreme flattening and lateral extension of the theca lead to the conclusion that the whole skeleton lay flat on the sea-bottom. ‘The knobs on the reverse side of the frame and the strut on that side served to give support to the flexible integument. Remarkable as this form appears to be among the Cystidea, it is not alone, for C. curvata (save in the absence of the club-shaped spines upon its dorsal surface) is a near repetition of this prolate type (see text-figs. 24, 25, op. cit., p. 409), and Ceratocystis Pernert, Jaekel, _ from the Middle Cambrian of Bohemia, is also remarkable for its boot-like form (see p. 423, text-figs. 33, 34). The Pelmatozoan life was a very simple existence: its members were mostly sedentary (if not always attached), receiving their food- particles along specially constructed food-grooves, subsisting, like their neighbours the Protozoa, Brachiopoda, Lamellibranchia, and Tunicata, on the currents made by their podia or cilia in the sea, which with its stream brought them the needful supply of aliment. Many of the more energetic members of the Eleutherozoa (the sea-urchin, starfish, and sea-cucumber) indulge in a predaceous and peripatetic existence, filling their stomachs with a selected and more attractive diet. But we have already trespassed upon our allotted space, and can only refer to the ingenious explanation of the author (pp. 415-17) to show how Colothurnus, with the help of its short stalk, its flattened body, and its rigid frame, furnished with knobs and spines, sustained life by lying flat upon the sea-floor, and through all its vicissitudes always managed ¢o keep its right side up. 1 See Pl. XIII, Fig. 1 (a line of fifteen elliptical openings parallel to the marginal plates 5-7). GroLt. Mac. 1913. Puate XIII, : _ | tongue toe-spine brachiole Bee Ni Ww jo, SJ ball of foot, \ yd SEG 1. OBVERSE. antanal lobe tongue | toe-spine B} 2. REVERSE. | | 1, 2, Cothurnocystis Hlize. 3, Dendrocystis scotica. Caradocian: Girvan, Ayrshire. Reviews—Professor Gadow— Wanderings of Animals. 423 And now the reader must be left to follow the author through the 172 quarto pages of this most interesting monograph, so fully and finely illustrated. We have been permitted by Dr. Bather’s kindness to reproduce three text-figures of two species from Girvan in our Plate XIII, which will show how divergent were these early forms of life among the Pelmatozoa. Daly WW EXPLANATION OF PLATE XIII. Figs. 1,2. Cothurnocystis Hlize, Bather. Reconstructions of the two faces, based on the various specimens mentioned in the text. Probably no individual quite reached the size of these figures, though a few fragments come yery near it. The numbers 1-11 refer to the marginals beside which they are placed. The proximal and median regions of the stem are drawn, with a few columnals of the distal region. Fig. 1. The obverse face, showing the vent just below the number 11, the subvective system close to marginals 5-7, and the irregular rounded plates of the integument. Fig. 2. The reverse face, showing the strut, the knobs on 2, 3, 6, 7, and the flattened plates of the integument. Fic. 3. Dendrocystis scotica, Bather. Between the anal lobe and the stem the plates of the vent form a projection. Both fossils are from the Starfish Bed in the Drummock Group, Thraive Glen, Girvan. II.—Tur Wanperines or Anrtmats. By Hans Gapow. Cambridge Manuals of Science and Literature. Cambridge: University Press, Toon melricey ls) N this little book of 150 pages Dr. Gadow has succeeded in giving | a sketch of the distribution of animals which will be useful to students of geology and others seeking an introduction to this branch of science. Perhaps the most interesting chapter is that on the ‘‘Features of Environment”, in which he describes the life of tropical forests, of deserts, and of high mountains as examples of contrasted habitats, and shows how these help or hinder the spreading of certain types of animals. It is significant of the changed standpoint of modern zoogeography that the book does not contain one.of the familiar maps showing the world divided into zoological ‘regions’. Instead of it we have a series of maps, showing, in the first place, the actual distribution of certain selected groups of terrestrial vertebrates, and, in the second place, the changes in configuration of the great land masses in the successive geological epochs since the Trias. These latter maps, as Dr. Gadow is careful to explain, are to be regarded as tentative and hypothetical; ‘‘they will be objected to by the timid, on principle ; eritics with more expert knowledge will amend them.” Of course, in a work of so wide a scope, inaccuracies in detail are likely to be discovered here and there by the specialist. There is no trustworthy evidence for the occurrence of crayfishes in Fiji or Melanesia (p. 92), or for the statement that ‘‘some existing species’? of Scorpions ‘‘ date back to the Coal-measures”’ (p. 93). Dr. Gadow’s vigorous, though not always very careful, style has betrayed him on p. 15 into the assertion that ‘‘the search for generally applicable regions is a mare’s nest”! 424 Reviews—W. M. Newton—Figure Stones. III].—Pxorocrarpaic SuprLemMent to Sranrorp’s GrotocicaL ATLAS or Great Brrrain anp Iretanp. Arranged and edited by H. B. Woopwarp, F.R.S., with the co-operation of Miss H. D. SHarPe. 8vo; pp. 113, with 108 plates. London: Edward Stanford, Ltd., 1918. Price 4s. net. WAKM welcome is assured to this supplement to the Geological Atlas. he editor, collecting his material from numerous sources, has selected 108 photographs of the most typical sections in the British Isles. Great care has been exercised in the choice of negatives, and the printing is good. The photographs are reproduced as half-page plates, each being accompanied by a brief explanatory notice with references to original publications and to the maps in the Geological Atlas. The arrangement is as far as possible chronological, and there is a good index of formations, localities, and authors, so that the book is one of ready reference. IV.—Ficure Stones. On Panmortraic Ficures or FLinr Founp IN THE OLtp RIVER ALLUVIA OF EneLaAND AND FRANCE, AND CALLED Ficure Sones. By W. M. Newron, F.R.Anthrop.Inst. Reprinted from the Journal of the British Archeological Association, March, 1913. 8vo. London: at the Bedford Press. ie fantastic forms assumed by flints in the Chalk are familiar to everyone who has visited sections in the upper strata of that formation, and forms suggestive of many different kinds of animals— birds, beasts, reptiles, and fishes—have been rudely modelled by Nature. These have sometimes been actually taken to represent the creatures themselves in a fossilized condition, as in the ‘‘ Facts and Fossils adduced to prove the Deluge of Noah’’, by Major-General Twemlow (see Grot. Mag. for 1869, p. 81). In other geological formations nodules of ironstone and argillaceous limestone sometimes assume forms suggestive of different animals, as in the concretions of the Champlain Clays of the Connecticut Valley, described by Mr. J. M. A. Sheldon (see Wature, April 11, 1901). The specimens to which Mr. Newton directs special attention have been obtained by him and by workmen in his employ from a gravel- pit at Dartford in Kent, and they consist of flint-stones that have probably in all cases been naturally derived from the Chalk and embedded in the ancient valley gravel. At the same time it is not impossible that Paleolithic Man might have picked up some flints from the talus of a chalk cliff. Forms described and figured by Mr. Newton have rude resemblances to fishes, birds, a tortoise, deer, horse, rhinoceros, elephant, etc., but he does not as a rule suggest any definite identification. The allegation is that these and other stones attracted the attention of Paleolithic Man, that he recognized a rude sort of animal form, and touched up the stones, where he could improve the resemblance, by chipping cavities for eyes, nose, or mouth, and in other ways slightly modifying the natural shape of the flints. There is nothing absurd or impossible in the suggestion. The pictorial engravings of various Reviews—John Ball—Phosphates of Egypt. 425 animals on stone, bone, horn, and ivory, from cavern deposits of Paleolithic age, are well known, and figure stones have been regarded as ‘‘first attempts at sculpture by Prehistoric Man”. In considering the subject it is especially interesting to know that Boucher de Perthes in 1849 had figured flints suggestive of animal forms, and later on in 1861 (as pointed out by Mr. Newton) he drew attention to the importance of observing whether the stones had been notched or otherwise chipped so as to indicate the handiwork of man. It was early in 1902 that Mr. Newton discovered his first figure stone from the Dartford gravel. The deposit there is about 18 feet thick and about 65 feet above O.D., and Mr. Newton obtained permission to collect any curious stones and to receive the aid of the workmen in putting aside similar specimens. At the end of the year the pit would have been closed, but as ‘‘such remarkable examples of figure stones with intentional work upon them” had been obtained, Mr. Newton arranged to work the pit at his own expense, and for a further period of five years some 5,000 tons of gravel were excavated and examined. He remarks that ‘‘ At an early period of my enquiry it became evident that I had chanced upon the site of a Paleolithic settlement of great antiquity—implements, cup-stones with worked rims, rings of flint, anvils (so-called), and many curious shapes in worked flint made their appearance; among the latter the forms of animal heads predominated, the cups taking next place in point of numbers, implements [occurring] in very small quantity considering the vast amount of gravel excavated”. At Swanscombe, on the other hand, the gravels have yielded numerous implements but very few cup-stones, and rarely a figure stone. Thus Mr. Newton points to the two settlements as affording evidence of distinct industries. It is indeed remarkable that the figure stones should be thus locally abundant, a fact which supports the view that many were intentionally gathered together by man. The careful particulars given by the author, and his impartial explanation of them, deserve all consideration. V.—PuospHates oF Heyer. TopoGRAPHY AND GroLocy oF THE PuospHatTEe Disrrict or SAFAGA (Kastern Dursrrt or Eeypr). By Joun Batt, D.Sc., F.GS., Ministry of Finance. Survey Department, Egypt. Paper No. 29. Cairo, 19138. AFAGA is a small district on the Red Sea just to the south of the Gulf of Suez. The phosphate deposits occur on either side of the Wadi at distances of from 12 to 22 kilometres inland. The Um-el-Huetat mines are connected by railway with the port, and the climate is said to be extremely healthy. ‘he geology consists of Alluvial beds, Hocene limestones, etc., Upper Cretaceous limestones and marls, Phosphate beds and cherts, also of Upper Cretaceous age, Nubian sandstones, and Crystalline rocks. Fossils are scarce, but ‘“‘the beds are doubtless of Danian age”’. Maps, sections, and views accompany the paper, which concludes with a complete list of all publications issued by the Survey Department up to date. 4.26 Reviews—Department of Mines, Canada. ‘A Brief Note on the Phosphate Deposits of Egypt,” by Dr. John Ball, has also been published as Survey Department Paper No. 30 (Cairo, 1913). The author calls attention to the extensive beds of phosphate of lime which occur in various parts of the deserts of Central Egypt, in sedimentary strata belonging to the Upper Cretaceous system. Their commercial value was pointed out by the Geological Survey in 1900, and it is highly satisfactory to learn that while the output in 1908 was 700 tons, and in 1911 as much as 6,425 tons, in 1912 it was 69,958 tons. VI.—Department oF Mines, CanaDa. E have received vols. v and vi, which complete ‘ An Investigation of the Coals of Canada with reference to their Economic Qualities ’’, by Messrs J. B. Porterand R. J. Durley (1912). We have also received a work entitled ‘‘ Tourbe et Lignite, leur Fabrication et leurs Emplois en Europe’’, by Mr. E. Nystrom (1913). In this volume the author gives the results of a personal study of the » industries connected with peat and lignite (or Brown Coal) in various parts of Northern Europe, the object being to aid the development of the peat industry in Canada. The methods and processes of working peat were examined in Sweden, Norway, Finland, Russia, Denmark, Holland, and Austria; and of peat and lignite in Germany. The volume is mainly of technical interest ; the author gives a brief account of the classification and composition of peat, and then passes on to practical matters, giving detailed accounts of his observations, with illustrative plates and text-figures of implements and machines employed in the cutting of peat and in its fabrication into various forms of fuel. ‘There are views of the excavations, of blocks and stacks of peat, and of methods of transport. Accounts are also given of the uses of peat for moss-litter and other economic purposes. We have further received the Annual Report on the Mineral Production of Canada for the year 1911 (1913), by Mr. John McLeish. The chief products are copper, gold, iron, lead, nickel, silver, asbestos, coal, gypsum, petroleum, pyrites, quartz, and salt. VII.—Tue Macneric Iron Sanps or Natasoxwan, County oF Saguenay, Province or QuesBec. By G. C. Mackenzrm. 1912. | fJ\HIS has been published as a separate report. The Iron Sands consist chiefly of quartz, felspar, garnet, olivine, magnetite, and ilmenite, and they occur on the north shore of the lower St. Lawrence river and gulf. The deposits vary much in extent and thickness, and they appear worthy of practical attention in not more than three or four localities. To be of commercial value it is necessary to separate not only the magnetite and ilmenite from the other minerals, but also the major part of the ilmenite from the magnetite. Only one serious attempt has been made to concentrate and smelt the magnetite. This was at Moisie, about 330 miles east of Quebec City; but the works have been closed. It is pointed out that the Natashkwan sands constitute one of the most promising of the deposits, as there is a treeless dune area which ‘‘ contains at least 500,000 tons of magnetic iron concentrate that will average 67 per cent in iron’’. Reviews—Brief Notices. 427 VILI.—Brier Notices. 1. Prrmo-Carponirerous Ick Acre 1n Western AvsrrariA.—This subject was dealt with by Mr. A. Gibb Maitland in his Anniversary Address to the Natural History and Science Society of Western Australia (vol. iv, session 1910-11). The essay is well illustrated by map, sections, and photographic views. 2. Gxotoetcat Survey or Soura Avsrratra.—In Bulletin No. 2 (1913), the Government Geologist, Mr. L. Keith Ward, discusses the possibilities of the discovery of petroleum on Kangaroo Island and the western coast of Hyre’s Peninsula, and comes to the conclusion that the facts do not justify the expenditure of capital in boring for oil. Some account is given of the rubber-like material known as ‘coorongite’, but there appears to be no genetic connexion between it and petroleum. 3. Mrnine in Soura Avusrratia.—The Review of Mining Operations in the State during the half-year ended December 31, 1912 (No. 17, 1913), gives satisfactory accounts of the production of copper, gold, and silver; other minerals obtained include lead and iron ores, uranium ores, gypsum, and graphite. 4. Inpran Arrotrres.—G. de P. Cotter, B.A., contributes ‘‘ Notes on Indian Aerolites recorded since 1906’’ (Rec. Geol. Surv. India, vol. xlii, pt. iv, p. 265). The paper gives details of six falls, viz., Vishnupur, Chainpur, Mirzapur, Baroti, Khohar, and Lakangaon. It is admirably illustrated by fourteen photographs of separate stones, and by a map of the Chainpur fall. The mineral constitution of the stones is only discussed very briefly. 5. THe Bernese Jura.—The structure of the Bernese Jura finds an able expositor in Dr. P. Schlee, who in an interesting paper published in the Mitth. geogr. Gesellsch. Hamburg, xxvii, 1913, illustrates his remarks with a fine series of photographic reproductions, a map, and sections. The paper can be obtained separately from Friederichsen & Co., Hamburg, for 3 marks. 6. Trrmires anp GxroLtoay. — Mr. Donald Steel writes in the American Naturalist, July, 1913, on this subject. He does little more than record the facts, but we gather from a perusal of his paper that the work of the Termites is much like that of worms, a turning over the surface soil. The Termite, however, piles the soil up into hillocks, which are themselves worn down again by storms, and gradually spread over the surrounding country. 7. Tse Laypns or Gascoeny.—M. Edouard Harlé (Bull. Soc. géol. France (4), xii, 1912) has investigated the Landes of Gascogny, and comes to the conclusion that far from being extremely old and entitled to the term ‘ Pénéplaine landaise’ of authors, these tracts are quite modern and still in process of formation. They are due to the prevalent westerly winds, are of different ages, and. continually changing. In the same communication Harlé traces the changes in the bed of the River Adour, the struggle between that river and the dunes, and their influences on each other. 428 Reports & Proceedings—Geological Society of London. ie > @ eS ANS) + PO Gr BD ilaNG_S: GeoLocicaL Sociery oF Lonpon. June 25, 19138.—Dr. Aubrey Strahan, F.R.S., President, in the Chair. Mr. C. Dawson, F.S8.A., F.G.S., exhibited zinc-blende occurring in ironstone nodules which contain plant-remains, in the celebrated plant-bed of the Fairlight Clays, Fairlight, near Hastings. He remarked that the form is crystalline and the ore is frequently found filling up cavities left by the decayed vegetable matter. Zinc-blende is not known to occur at other horizons in the Weald, nor anywhere else in the South-East of England. It is probably segregated from older rocks of which the Wealden strata are composed. He also exhibited pisolitic limonite, which occurs in considerable quantities at one or two horizons in the Fairlight Clays, near Hastings. On the shore at Pett Level, near Fairlight Cliff end, a very large deposit is found, just above the ordinary high-water mark. The deposit consists of minute spherical grains or nodules of sand-like condition. These, on being analysed, prove to contain 60 per cent of iron-oxide. In the cliff the iron-ore occurs in bands, the grains of which it is composed forming a compact grey con- glomerate that turns dark brown on exposure. Many pieces of the conglomerate are to be found on the shore in a rolled condition. When disintegrated, they are deposited by the joint action of the eastward drift of the tide and the south-westerly wind along the shore. The deposit last year measured about half a mile in length, by about 30 or 40 yards in width, and was 3 to 4 feet ra: The following communication was read :— ‘‘The Miocene Beds of the Victoria Nyanza and the Geology of the Country between the Lake and the Kisii Highlands.” By Felix Oswald, D.Sc., B.A., F.G.S.; with Appendices on the Vertebrate Remains, by Charles William Andrews, D.Sc., F.R.S.; on the Non- Marine Mollusca, by Richard Bullen Newton, F.G.S.; and on the Plant-remains, by Miss N. Bancroft, B.Sc., F.L.S. The Miocene beds of the eastern coast of the Victoria Nyanza, south-east of Karungu, form a narrow zone (covered with black earth) at the foot of cliffs of overlying tepheline-basalt, and are only exposed in a few gullies. The whole series is conformable, dipping 8° north by west. 1. Beds 1-12. An upper group, about 70 feet thick, of grey and brown clays and shales, with occasional current-bedded sandstones containing terrestrial shells (Zropidophora, Cerastus), as also calcified tree-stems in the uppermost bed. 2. Beds 138-25. A middle group, about 30 feet thick, of red and grey clays, with white sandstones in the lower half. No bone-bed, but fragmentary Chelonian and Crocodilian remains occur sparsely throughout the series. Persistent horizons are a travertinous marl- stone (No. 14) containing Ampullaria and Lanistes ; a thin sandstone (No. 16) yielding Hyracoid jawbones; and a gravel (No. 24) yielding teeth of Dinotherium, Protopterus, crocodile, ete. I Reports & Proceedings—Geological Society of London. 429 3. Beds 26-87. A lower group, about 385 feet thick, of current- bedded sandstones and gravels passing down into clays and marl- stones. A conglomerate of calcareous nodules overlies gravelly sandstones (No. 31) containing isolated bones of Dvinotherium, Anthracotheroids, rhinoceros, giant tortoises, etc., indicating a Lower Miocene (Burdigalian) age, with Ampullaria, Cleopatra, and terrestrial shells ( Cerastus). These fluviatile sediments were deposited in a lagoon, and were derived from gneisses, andesites, and quartzites that still occur in situ to the eastward. Calcareous springs acted intermittently, and the sediments became finer and less fossiliferous as the river-system reached its base-level. The series overlies gneisses and amphibolites, with a north-north- westerly and south-south-easterly strike. In searching for the extension of these beds the author found them to be completely denuded on the south, while on the north they disappear beneath the basalt-plateau. Marching up the Kuja Valley, he found the upper beds lying on old andesite 15 miles inland, on the line of strike. Evidence is adduced of the lake having stood about 330 feet above its present level, and of a rejuvenation of the rivers since the formation of a gneissic peneplain, above which the Kisii Highlands rise in steep escarpments of ripple-marked, unfossiliferous, quartzitic sandstones, probably Devonian, separated from the underlying gneisses and schists by an extensive dolerite-sill, From Kisii the peneplain was traversed to the region of nepheline lavas near Homa Bay. Lake Simbi, an explosion- crater, was investigated; and a Pliocene series was found north of Homa Mountain. The vertebrate remains described by Dr. C. W. Andrews include Proboscidea, Hyracoidea, Artiodactyla, Rodentia, and Reptilia, and fully support the suggested occurrence of Lower Miocene deposits on the shores of the Victoria Nyanza. A deposit of probably Pliocene age yielded a new(?) species of Hlephas, also bones of antelopes and baboons. The non-marine Mollusca associated with the Miocene vertebrates are freshwater and terrestrial shells which all belong to existing species. Only Tuttle Hill Quartzite Rog errr | Park Hill Quartzite . (3) Some rFurrHeR Nores on PALHZOXYRIS AND OTHER ALLIED FossiIis, WITH SPECIAL REFERENCE TO SOME NEW FEATURES FOUND in Veracapsuta. By L. Moysry, B.A., M.B., F.G.S. INCE the publication of a paper on Palgoxyris and other allied organisms in 1910! so many fresh specimens have come to hand, and, as was only natural, several previously unrecorded examples have been described, notably some from the Lancashire Coal-measures by Mr. J. Wilfred Jackson,” that it seems desirable to record any new features that have been found in the later material, and also any new facts that may lead to the elucidation of the nature of these still very enigmatical organisms. Taking in the first instance the genus Palgoxyris. The species Paleoxyris nelicteroides (Morris) has been lately found in very large quantities in the Notts and Derbyshire Coal-field. In this area they seem to be restricted to an horizon extending from the roof of the Top Hard Coal downwards to above the Ell Coal; a careful search in the measures below, wherever these are exposed, has not resulted in the discovery of any trace of this fossil. They were, some years ago, discovered in great numbers in the open working of the Barnsley thick coal at Worsborough, near Barnsley, where some 3800 odd specimens were collected by Mr. W. Gelder from a space 6 or 7 yards in circumference, together with some specimens of P. prendel (Lesq.) and P. carbonaria (Schimper). A hurried search in other claypits at horizons above and below this coal during the Sheffield meeting of the British Association in 1910 produced enough specimens to make it probable that, if looked for, they may prove to be similarly quite common fossils in the great 1 L. Moysey, Quart. Journ. Geol. Soc., vol. Ixvi, pp. 329-45, pls. xxiy—vii, 1910. 2 J. Wilfred Jackson, Lancashire Naturalist, January, 1911. 3 R. Kidston, Naturalist, 1897. 454 Notices of Memoirs—British Association— coal-field of which the Notts and Derbyshire area is merely an extension. In fact, it seems probable that the habit of collectors to look for fossils only in the Coal-measure shales, to the neglect of the ironstone nodules, may account for the paucity of specimens found in other coal- fields. ’ The other species, Paleoxyris carbonaria (Schimper) and Pal@oxyris prendeli (Lesq.), seem, on the contrary, to be extremely rare in this area, and, when found, they are usually associated with quantities of P. helicterordes. Vetacapsula coopert (Machie & Crocker)’ must still lay claim to being an extremely rare fossil. This genus is not restricted to a definite horizon in Derbyshire and Notts Coal-fields, but has been found to range from between the Waterloo and Ell Coals at Newthorpe Claypit, downwards to the Kilburn Coal at Loscoe Colliery. Three new specimens have been obtained—two from the Silkstone Coal and one from the Kilburn Coal. One of these, a specimen from the Silkstone Coal of the Calow Colliery, Chesterfield, shows a feature of great interest. When first found the fossil presented the appearance of a very much crushed example; but careful development revealed the fact that the fossil was, in reality, a perfectly normal flattened specimen, and the feature that gave rise to the apparent deformity was the presence of a medial, longitudinal flange, or fin-like structure, which extends along the ‘median raphe’, emphasized by the original describer of the genus, dismissed in my former paper as possibly due to crumpling, and again brought into prominence by Mr. J. Wilfred Jackson. It seems now that this ‘median raphe’, which appears to be a constant feature in every specimen recorded, may be caused in the ordinary specimens by this flange being torn off, and being left embedded in the matrix of the counterpart. It is also instructive to compare this new-found flange with that described by Mr. Bashford Dean on the egg-case of Chimera collet. From the examination of the four specimens in the author’s collection and others elsewhere it is becoming more apparent that there are two distinct species included under the name of Vetacapsula coopert. Owing, however, to the at present uncertainty as to their affinities, and to the rarity of their occurrence, it seems best still to keep them under one trivial name and separate them by applying the designation ‘forma a’ to those specimens in which the pedicle expands suddenly into the body, forming a distinct shoulder in the lower third of the body and giving rise to a ‘deformity’ or crumpling in that region; and the designation ‘forma 8’ to those in which the pedicle expands more gradually into the body, giving to the specimen an ovate contour, with the ‘deformity’ or crumpling in the centre. A curious and interesting feature is seen on the outer edge of all specimens conforming to ‘forma 8’. Just before the body contracts to form the beak there is found, by examination with the ordinary lens, a minute crenulation or crimping of the edge of the fossil, which may be compared with the markedly rugose lateral webs seen on the egg-cases of Chimera collet, Rhinochimera, and other Chimeroids. 1 E. J. Machie, Geol. and Nat. Hist. Repertory, vol. i, pp. 79-80, 1865-7. Abstracts of Papers read on Geology. 455 _ One fresh specimen of Vetacapsula johnsoni (Kidston) has come under notice from the Worsborough open works near Barnsley. It is in too crushed and imperfect condition to show any new features. A new species of Vetacapsula has been recently described by Mr. Good! from Pembrokeshire. It is very similar to Vetacapsula johnsont, but is extremely small, measuring only 5 mm. across, whereas Vetacapsula gohnsont measures 20 mm. A new specimen of Fayolia crenulata (Moysey) has been discovered lately from a small heap of nodules still remaining from the ~ Shipley Claypit. The former example from Shipley consisted of the middle portion of the organism 11cm. long; another specimen, doubtfully referred to Fayolia sterzliana (Weiss), from the same locality, was evidently nearing its proximal or pedicular termination. The new specimen is of interest mainly because it shows the apex or distal termination, which appears to have been dome-shaped. The chief feature is the marked exaggeration of the crenulate ‘ collerette ’ which arises from the junction of the two spiral valves, and which forms a sort of spiral ‘corona’ round the apex of the fossil, strongly reminiscent of the corona at the summit of the egg-case of Cestracion phailippr. (4) On tHE ConDITIONS WHICH GOVERN THE TRANSPORT AND AccumuLation oF Derritus By Winp and Water. By VaveHan Cornisu, D.Sc., F.R.G.8., F.G.8., F.C.S8. fY\HE author dealt with the conditions of the transport of detritus superficially and in suspension. He pointed out that the rate of subsidence is the constant which best defines the behaviour of a granular material with respect to transportation by currents. He showed how detritus may be classified in three groups according to the value of this constant, these groups being familiar as shingle, sand, and mud, in the case of water-borne material, and gravel, sand, and dust in the case of wind-borne detritus. It was pointed out that the change of direction of the vertical currents in sea-waves does not occur simultaneously with the change of direction of the horizontal currents, and it was shown that the result of the sequence of the changes is to endow waves with a shore- ward action upon shingle and the coarser kinds of sands independently of any motion of translation in the water. In tides also, rise does not commence simultaneously with flow, nor fall with ebb, and the author showed that the sequence of these changes is such as to make the flood tide more effective than the ebb as an agent of littoral drift, apart from any greater speed of current. Examples were given of the different positions in which deposits of detritus accumulate according to the rate of subsidence of the particles. An explanation was given of the effect of a change in the inclination of current to the horizontal in sorting heterogeneous detritus, and examples were given for wind-borne material. 1 R. H. Good, Quart. Journ. Geol. Soc., vol. lxix, p. 266, pl. xxx, fig. 3, 1913. 456 Notices of Memoirs—British Association— (5) On tHE CorRELATION OF THE LEICESTERSHIRE CoAL-FIELD. By Rozsert Doverass Vernon, B.A., B.Sc., F.G.S. fY\HE following is a preliminary account of a study in the correlation of the coal-fields of the eastern portion of the great Midland coal basin. The area in question includes the Derbyshire and Nottinghamshire Coal-field in the north, the Warwickshire Coal-field in the south-west, and the Leicestershire Coal-field, which lies midway between the two. It is with the latter that we are here chiefly concerned. The Carboniferous rocks of Leicestershire include Carboniferous Limestone, Limestone Shales, Grits, and Sandstones that have been referred on lithological evidence to the Millstone Grits, and, lastly, the Coal-measures. Such a sequence at once suggests a correlation with the Derbyshire and Nottinghamshire type, but the presence of unusually thick seams of coal which split towards the north favours a comparison of the Middle Coal-measures of Leicestershire with those of Warwickshire. Finally, in the complete absence of the Transition Series and Upper Coal-measures and the presence of a complex fault system, the Leicestershire Coal- field stands quite apart from either of its neighbours. For the detailed correlation of the Upper Carboniferous of these tectonic basins we have several independent criteria, both physical and paleontological, but strong theoretical objections may be urged against the use of physical criteria alone, and in practice it was found to be impossible to use either the important sandstones or the seams of coal in the correlation even of the eastern and western portions of the Leicestershire Coal-field itself. The problem was then attacked from the paleontological side. Fossil plants proved of relatively little value in the subdivision of the Leicestershire sequence, because the lowest and the highest plant-bearing horizons both appear to fall within the Middle Coal- measures. ‘The freshwater lamellibranchiata (Carbonicola and its allies) were equally unsatisfactory, so that the work finally resolved itself into a search for Marine Beds and an attempt to lay down their outcrops on the 6 inch maps. Of the three more or less distinct districts into which the Leicester- shire Coal-field may be divided, the Central or Ashby area of so-called unproductive measures yielded no fossils, either plant or animal, and the age of the beds, whether Lower or Middle Coal-measures, remains an open question. The Eastern or Cole Orton area presents serious difficulties to the collector, being for the most part a concealed coal- field worked under a thick Triassic cover, and the results obtained were merely of local interest. Attention was finally concentrated on the western or Moira area, where the sequence is more complete than in the rest of the coal-field, and exposures are much more numerous. Many fossiliferous horizons were discovered, which yielded a rich flora, several rare Crustacea, some fragmentary fish-remains, numerous freshwater lamellibranchiata, and above all an abundant marine fauna from several different horizons and many localities. Unfortunately, no indication of the well-known Ganister Coal Marine Bed (Alton Coal of Nottinghamshire) has yet been found in Leicestershire. Abstracts of Papers read on Geology. AD57 The thickest Marine Bed, which also has the richest fauna, occurs in the higher portion of the Middle Coal-measures about 260 yards above the Moira Main Coal; it crops out at many places in the Moira, Swadlincote, Church-Gresley, and Woodyille district, and the outcrop has been laid down on the 6 inch scale. Such mapping is of value, since for want of an index bed it has hitherto been impossible to map any seam of coal above the Main Coal owing to the variable character of the beds in the higher portion of the Coal-measures, and the structure of this part of the coal-field was, therefore, imperfectly understood. Using this Marine Bed as an index bed, we can now fix the position in the sequence of the Moira Sandstones and Grits and of the valuable series of pot, pipe, and fireclays on which the prosperity of this district so largely depends. The main interest of this Marine Bed is that in stratigraphical position and in faunal contents it is comparable with the Gin Mine Marine Bed of the North Staffordshire Coal-field, with the Mansfield Marine Bed of the Yorkshire and Nottinghamshire Coal-field, and with the Pennystone Ironstone Marine Bed of Coalbrookdale. The following is a correlation of the Productive Coal-measures of the East Midland Coal-fields, based upon the chief marine trans- gressions :— Yorkshire and Nottinghamshire | West Leicestershire Warwickshire Coal-field. Coal-field. Coal-field. Mansfield MarineBed.| Pottery Clay Marine | Doubtful } Bed. Strata, 930 feet. Strata, 750 feet. Strata, thickness | Middle unknown }Coal- Middle and | Marine Bed 300 feet | Marine Bed above the | Marine Bed| measures. LowerCoal-< below the Top| Main Coal. above the measures. Hard coal. : 7 foot Coal ; Strata, 1,600 feet. Strata, thickness un- known. Marine Bed above the | Doubtful. Absent. Alton (Ganister) coal. ; In conclusion, it is shown that in colour, mode of weathering, and other characteristics these Marine Beds are in every way comparable with modern ‘ Blue Muds’. (6) On roe Srream-courses oF THE Brack Country Prareav. By Henry Kay, F.G.S. HE Black Country plateau is roughly outlined by the 400 feet _ contour-line between Stafford, Worcester, Stratford, and Burton, and is identical with the anticline of the South Staffordshire Coal-field, plus the north-western parts of Cannock Chase and the Warley—Barr area eastward. On its eastern and western sides are synclinal valleys opening to the Trent and Severn. 458 Notices of Memoirs—British Association— It is surrounded by a marginal hill barrier, and has large hill masses at Cannock Chase and the Clent region; while it is crossed by hill ranges from Bushbury to Barr Beacon, from Wolverhampton to the Lickeys, and from Quinton to Birmingham. The surface is thus divided into four interior basins, forming separate drainage areas. Save for the exits from these basins, the margin is broken in two places only. The chief physical feature is the possession of the crucial portion of the Midland watershed, which runs across the plateau from Wolverhampton to the Lickeys, and thence eastward along the southern margin. Arterial drainage is supplied by the Trent and Severn, the former draining five-sixths of the plateau, and the latter receiving only the southward marginal drainage and that of the Stour basin. The eastern syncline is occupied by the River Blythe-Tame flowing north. The watershed at the southern end of this valley has retreated northwards for 4 miles in post-Glacial time. The western syncline was formerly drained towards the Dee, and the head-waters of the Severn were originally around Kidderminster, the Clent range being united with the Enville Hills further west. The principal outlet towards the Dee was by the Church Eaton Water, and the outlet into the Trent below Stafford not then in existence. This syncline is now drained northward by the Penk into the Sow and Tame, and southward by the Smestow—Stour into the Severn. Stream piracy is manifest near Wolverhampton. Marginal streams are characterized by excessive activity, especially southward, notable examples being the Arrow and the Alne. The Arrow, however, represents the captured head-waters of an ancient river flowing through the Moreton Gap into the Evenlode, the pirate stream being the Warwickshire Avon, a strike river originally confined to the country west of Evesham. The watershed then ran southward from the Lickeys to the Cotswolds, being now represented by a long, narrow promontory reaching into Evesham and by Bredon Hill southward. Internal drainage is confined to the four basins. The Cannock basin has now no trunk stream, its waters uniting near the exit below Cannock to form the Saredon Brook. Glacial modification is much in evidence, the south-eastern portion having formed a lakelet with gorge-like overflow through Walsall. The margin of this basin has twice been broached by marginal streams. The Tame basin is triangular in shape and formed by the union of two basins reaching back to pre-Triassic ages, a large buried stream- course existing at Moxley, whilst a very great valley is traceable upwards through Smethwick, Oldbury, and Blackheath. At this point two buried stream-courses are found, each filled with material transported from the Clent Hills. ‘Lhe inference is that this marked the original source of the Trent, as the Upper Trent Valley appears to be of more recent date. The Stour basin is likewise a combination. Streams descend south-west from Dudley to Stourbridge, and north-eastward from Clent to Halesowen. They are united by a succession of gorges 4 miles in length. This basin is a remarkable instance of extreme post-Glacial denudation to a depth of 300 feet. The Halesowen Abstracts of Papers read on Geology. 459 streams represent the original head-waters of the river once flowing through Blackheath, Oldbury, and Smethwick. The Rea basin possesses three eastward-flowing streams successively diverted N.N.E. through Birmingham by a stream working back along the Rea fault. Two of these were captured in pre-Glacial time, the third in consequence of glacial lakelet overflow. The present thrice-notched ridge at King’s Heath represents the pre- Glacial land surface. The Middle Cole Valley is wholly post-Glacial. The Lickey anticline has undergone elevation since the initiation of the Rea streams—i.e. in post-Tertiary time. It is crossed by three waterworn gaps excavated part passu with this uprise. The southernmost of these now drains into the River Arrow. _ The Warley—Barr area is a region of Tertiary uplift, across which rivers occupying the old pre-Triassic valleys have excavated deep channels. All other streams in this area are very youthful. Conclusions.—The Trent drainage area has been subjected to excessive piracy and has steadily suffered loss. Its sole gain is that of the Penk at the expense of the Dee. The northern drainage is consequent on the formation of the South Staffordshire anticline, regarding the age of which it bears notable evidence. Speculations as to the former north-west extension of the Thames drainage must therefore be abandoned on reaching the area under consideration. (7) Ox some oF THE Basement Beps or THE GREAT OOLITE AND THE Crinoip Beps. By Epwin A. Watrorp, F.G.S. OWERBY, in vol. i Dhneral Conchology, describes a Brachiopod now known as Lhynchonella concinna. Itis figured on T. lxxxiii, 6 from Aynhoe in Northamptonshire. A note on a quarry in the Great Oolite made by the writer in 1883 fixes probably the source of Sowerby’s shell— AYNHOE ALLOTMENTS QUARRY. ft. in. 1. Humus . 183 2. Whitish Marl . SS 3. Marl crowded with Rhynchonella c concinna, Ostrea Sowerbyt, Natica, Modiola, Photadomya 2 6 4, Shelly Limestone, false- bedded 1g 5. Grey Marl : 2 1 6. Limestone, whitish : top course : 1 6 The Geological Survey found its stratum to be a convenient line of demarcation, as it rested upon a base of limestone graduating into the Stonesfield Series. The discovery of other strata on the borders of East Oxfordshire and West Oxfordshire necessitates the division of the Great Oolite and the separation of the new beds proposed to be classed as Sub- Bathonian. The old survey lines are thus sustained. The sequence suggested is as follows :— UPPER GREAT OOLITE.—1. Terebratula mawillata beds. 2. Calcaire a Echinodermes. LOWER GREAT OOLITE.—1. Striped Limestones. 2. Rhynchonella concinna beds. 3. Stonesfield Slate. SUB-BATHONIAN.—1. Striped Limestone and Crinoid beds. 2. Nesran ‘Series. 3. Striped Crinoid Marls. 4. Chipping Norton Limestones. 460 Notices of Memoirs—British Association— The new railway (Aynhoe and Ashendon) is cut along the divide between the Cherwell and Ouse Rivers, The missing Sub-Bathonian Series of the West lands were brought to view. Prominent there were White Calciferous Limestones and Striped Marls and Lime- stones. The author found the chalk-like limestone to be crowded with the decayed heads of large crinoids of which it was made. Above it passed into a blue crystalline limestone, here and there; a packed mass of the brachial joints of the crinoids. At the base of all was the stratum of black vertical stripes (the striped beds), the place of crinoid column and rootlets filled with carbonaceous granules from dark beds above. The beds are now known to be marine, not estuarine, as previously described. Sections of the chalk-like lime- stone showed a pavement of discs of the crinoid (Apioerinus) calyx. (8) On tHE SrructuRE or THE Lias Ironstone oF SourH WaRrwick- SHIRE AND OxForDSHIRE. By Epwin A. Watrorp, F.G.S. !J\HE ironstone of South Warwickshire and North Oxfordshire is got wholly from the Middle Lias. The Northamptonshire ironstone of the Inferior Oolite may be traced in the Burton Dassett Hills, where it passes into a useless sandstone. Beds of the Middle Lias stone are seen in the quarries packed with curved and interlacing stems something like masses of annelid tubes. They lie upon the bedding plane. Other beds of the fine pentangular and smaller ossicles of the Crinoidea range between. More rarely the round columnar stems of forms like Apiocrinus are found. The author infers that the sea floor of the Middle Lias was a tangle of crinoid growth, stage above stage. The Crinoid sea appears to have spread through the Midlands into Yorkshire. Occasionally are phases of invasion or dominance of shells of Brachiopoda. Beds of Rhynchonella tetrahedra and Terebratule are interspersed in the 25 feet of the ferro-crinoid rock-bed. The quarries and sections in the neighbourhood of Banbury show the several phases described. In the Nodule Bed at the base of the Ironstone Series (zone of Spirifer oxygona) crinoidal conditions appear in segments and stem casts, mingled with large mollusca. Microscopic sections present plates and segments of Crinoidea mingled with ferruginous Oolitic grains of large size and fox-brown colour. The superimposed bed, the Best Rag, has in sections smaller Oolitic grains of olive-green iron carbonate with ovoid calicular plates of crinoids, The Top Rag, a grey-green compact stone, is a tangle of crinoidal and other remains more or less broken and converted into Oolitic iron granules. The Road Stone, the higher beds, shows its organic structure mainly destroyed and converted into the ordinary red oxide. In 1896 I placed a short study on the making of the Middle Lias Ironstone of the Midlands before the Iron and Steel Institute, which appeared in their Proceedings. Abstracts of Papers read on Geology. 461 (9) Norges on tHE Frora anp Fauna oF tHE Upper Kevuper SaNDsTONES OF WARWICKSHIRE AND WorcrstersuirgE. ‘By L. J. Wits, M.A., F.G.S8., and W. Camesetx Suita, M.A., F.G.S. GROUP of sandstones associated with green shaly marls have been shown by Dr. C. A. Matley to form a more or less continuous belt in the Keuper Marls in Warwickshire, and to lie about 120 to 160 feet below the Rhetic. At the same horizon similar beds form an almost unbroken outcrop through Ripple, Longdon, Pendock, and Hldersfield in South-West Worcestershire, and were probably once continuous with the sandstones of Inkberrow and’ Callow Hill, near Redditch. Of the constituents, the thin-bedded sandstones are fine-grained, ripple-marked, and characterized by the presence of much calcareous matter and abundant rhombs of dolomite. The thicker-bedded sandstones consist mainly of grains of quartz, with felspar and the usual assemblage of heavy minerals in well-rounded grains; of these garnet is the most conspicuous. Close to the base of the group there is frequently a conglomeratic bed (‘ bone-bed’), composed of fragments of green marl, plants, bones, and teeth. Shales and steinmergel may occur with the sandstones. We are able to describe for the first time from the English Trias examples of the foliage and scales of the female cone of a Voltzia, closely resembling V. heterophylla, of the Bunter of the Vosges, and to record new occurrences of Voltzia, Schizoneura, Carpolithus, and, possibly, Yucecites. The plants.are associated with indeterminable teeth and bones of Labyrinthodonts, and with fish-remains, which are abundant in the ‘bone-bed’ and very rare at higher horizons. Fish-teeth, hitherto described as Acrodus ? keuperinus, are widely distributed, and prove, on microscopic examination of their internal structure, to be referable to Polyacrodus (Jaekel). Dorsal-fin spines and cephalic spines associated with these teeth probably belong to the same genus. Teeth similar to Phebodus brodiet have been found at Knowle. Phebodus, Semionotus, and Ceratodus have all been previously described from these beds. Cestraciont remains allied to Polyacrodus keuperinus are especially abundant in ‘ bone-beds’ at the base of the Lettenkohle in Germany, and its presence may be regarded as evidence of estuarine conditions. Ceratodus, on the other hand, occurs frequently in the Rheetic, a deposit usually accepted as marine, but its only living ally inhabits some rivers in Queensland. We have found Thracia ? brodiei at Shelfield. This lamellibranch was described by Mr. R. B. Newton as a truly marine form, but it is only represented by rather obscure casts. _Listheria minuta, a form that is probably never truly marine, is practically ubiquitous, and occurs in both shales and sandstones. The fauna and flora is thus seen to be a restricted one, though many specimens have been found, and their testimony on the origin and age of the deposit is inconclusive. 462 Notices of Memoirs—British Association— If we may judge from the lithology, the conditions which governed the formation of the ‘skerry-belts’ of Nottinghamshire and Leicestershire—namely, the arrival of floods of fresh water—probably acted more persistently in the area under consideration, as a result of its greater proximity to land. For not only are the beds very similar to the ‘skerries’, but in the ‘bone-bed’ or marl conglomerate we have positive evidence of littoral conditions. Thus we are not dealing with a pre-Rhetic incursion of the sea, but with a littoral facies of the Keuper Marls, formed where the water was at times sufficiently fresh to support a small fish-fauna and in sufficient motion to move coarse sediments. (10) On tHe Fossit Froras or tHe Sourn SrarroRDSHIRE CoaL-FIELD. By E. A. Newert Axper, M.A., Sc.D., F.G.S. HE rich series of floras of the South Staffordshire Coal-field has suffered much unfortunate neglect in the past. Several collections have, it is true, been made from time to time, but with very few exceptions they have never been described, and some of them are without proper records of locality and horizon. For such trustworthy records as exist we are chiefly indebted to Dr. Kidston and to his memoir published as far back as 1888. The number of species, the exact locality and horizon of which are recorded, is at present as follows :—Keele Series 16, Halesowen Sandstone Series 0, ? Brick Clay Series (Old Hill Marls) 8, Productive Measures 27. For some time past I have been endeavouring to extend our knowledge of the fossil floras of this coal-field, and I have been fortunate in receiving the active co-operation of several geologists resident in Birmingham and the neighbourhood, who have most kindly formed collections from particular areas, and forwarded the specimens to me for examination and description. In this way the material which I have myself been able to collect has been greatly extended. My thanks are in particular due to Mr. H. Kay, F.G.S., Mr. W. H. Foxall, F.R.G.S., Mr. W. H. Hardaker, M.Sc., and Mr. L. Jackson for their enthusiastic co-operation. Attention has been chiefly concentrated so far on the floras of the Brick Clays, and of the lowest beds of the Productive Measures on or about the horizon of the Bottom Coal. A considerable number of species have been obtained from both horizons, of which some are new records both to the coal-field and to Britain. This work is still in progress. Information has also been obtained as to the horizon and localities in which the petrified specimens, long known from this coal-field, occur, such information having been lost for many years past. In addition the first fossil plants from the Halesowen Sandstone Series have been unearthed by Mr. Kay, and here again both petrifactions and impressions occur. It is hoped that in course of time it will be possible to trace the floras systematically from the lowest to the highest beds of the Coal- measures of this coal-field. The material, however, has to be obtained as opportunity offers, and this preliminary note is intended merely to indicate the present progress of the work. Abstracts of Papers read on Geology. 463 (11) Ow Sysrems oF Forpine In THE Patmozorc anp Newer Rooxs. _ By G. Barrow, F.G.S. N a paper published by the Geologists’ Association the author has given a brief outline of the nature of the crystalline area of the Highlands and shown that it consists of three great lenticular masses of thermally altered rocks. It is further shown that the outer and uncrystalline margins of these masses all trend roughly north-east and south-west. The best known is that forming the south-eastern margin of the crystalline area, which the author has followed, where present at the surface, almost the whole distance from Stonehaven, on the east coast of Scotland, to Omagh in the north of Ireland. Recent work suggests that this margin is also present on the west coast of Ireland. _ This outer margin of crystallization is not confined to Scotland ; it is also present in Anglesea, where the margin of the crystalline massif is seen along a portion of the Menai Straits. It also occurs in the Isle of Man, where the old rocks are identical with those of the lower aureoles of thermometamorphism in the Southern Highlands. In both eases the trend of this outer margin is the same—north-east and south-west. Wherever this margin can be examined it has been found to be a great line of resistance, and the folding in the adjacent paleeozoic, and, at times, even newer rocks, is found to be parallel to it ; it isin fact the cause of the strike of the folding; under earth- stresses the softer rocks have buckled up against a great resisting erystalline mass. Thus, strictly speaking, there is no such thing as a Caledonian Movement; there are a series of resisting masses with parallel margins; the folding in North Wales is determined by the Anglesea Archean Rocks; Caledonia has nothing whatever to do with it. If, now, we turn to the area in the south of Britain, we find another system of folding ; this, too, the author believes to be due to a similar cause. The outer margin of the old crystalline rocks in Cornwall seems to be roughly east and west; it certainly is not north-east and south-west. It now remains to do in the north-west of France what the author has done in North Britain—1i.e. to trace out the outer margins of crystallization and prove that the so-called Hercynian system means simply that the boundaries of the resisting crystalline masses, against which the newer rocks buckle up, now trend east and west. If these facts are once grasped we have an explanation of the local departure of the strike of the folding in the north of England; the lines of resistance locally depart from their usual trend and the subsequent folding does the same. (12) On tHe Srrrorpis Limesrones or NortH WaRWIcKsHIRE. By G. Barrow, F.G.S. HE typical Spirorbis limestone is a rather compact rock, usually grey and generally containing the small fossil Spororbis carbonarius. The number of these varies greatly ; at times several specimens may be seen in one fragment; often it is difficult to find any, and, so far as experience has gone at present, they are never 464 Notices of Memoirs—British Assocvation— abundant in this area. Though the dominant colour is grey, the rock is often buff and occasionally almost white. The purest form of Spirorbis limestone occurs in masses of very variable size. The largest and most persistent bed is the Index limestone, which occurs roughly about 100 feet down in the Halesowen or Neweastle Group. This has often been confused with another and less’ persistent bed, lying about 100 feet further up and close to the base of the Keele Group. Other and less persistent bands have been met with in the Keele Group, notably by Mr. Cantrill. In addition to these distinct beds, which can often be traced for some distance at the outcrop, if the ground be free of drift, there are lenticles varying in length from a few yards to a few inches, and at times only scattered nodules. These smaller patches were found during the great drought, when the old marl pits in the Halesowen Group were completely dried up. Advantage was taken of this to clean the pits out, laying the rock sides bare, when these minor occurrences of the limestones were exposed. The limestones seem to have been built up of a series of films or layers, resulting from the evaporation of shallow sheets of lme- bearing water. When dried the film appears to have been cracked and more or less broken up, but re-cemented by later deposits of identical material; this in turn became broken up and re-cemented. The process was repeated till a bed several feet thick was at last accumulated. ‘The whole rock thus comes to have a clean sharp fracture, though its fragmental character is easily seen on a freshly fractured face. In this form, best shown by the Index limestone, there is a minimum of material other than lime brought into the deposit. A rough test of the brecciated original fragments shows the limestone to be nearly pure and containing about 95 per cent of carbonate of lime. From this we pass to the type containing small fragments of other material, such as marl, and the cementing matrix is not merely calcite, a considerable proportion of mud and sand being present. In this the limestone fragments are somewhat rounded, having been transported for short distances. At times the fragments are locally heaped up and the bed attains a quite abnormal thickness. The band at or near the base of the Keele Group shows this character in the cutting of the mineral railway above Kingsbury; the fragments have been heaped up till it has locally attained a thickness of 10 feet. The extreme type is really a cornstone, or a sandstone more or less crowded with rolled fragments of Spirorbis limestone. It is doubtful in this case if any of the rounded fragments are formed in situ; the whole rock seems to have been the result of flood action tearing up a deposit cracked by drying and transporting the fragments for some distance. There is strong evidence to support the view that two at least of these limestones were formed over a large area ; the Index has rarely been removed completely by this process; the one next above often has. How far the less persistent beds have been locally removed by subsequent erosion is at present an open question. This mode of origin of the more impure, possibly of all the Abstracts of Papers read on Geology. 465 limestones, is supported by the character of the sandstones. These at their base often contain abundant pellets of marl, which from their form appear to have been sun-dried and so rendered sufficiently coherent to be capable of transportation for short distances without losing their cuboidal form. The phenomena suggest formation in shallow water, during a dry epoch, subject to sudden or periodical floods. (18) Te Grotoey or THE District BETWEEN ABEREIDDY AND PENCAER, PremprokesHire. By A. Hupert Cox, M.Sc., Ph.D., F.G.S., and Professor O. T. Jones, M.A., D.Sc., F.G.S. N an introductory paragraph the authors referred to the work of previous observers, namely, Hicks, Reed, Elles, and Elsden, and to the visit of the Geologists’ Association during Easter, 1910, when results were obtained which suggested that this area required re- investigation. Examination by the authors has proved that the apparent sequence is extremely complicated by strike-faulting, and instead of Llandeilo and Bala rocks as previously supposed, Arenig and even Cambrian rocks form large areas of the coast. Part I. Abereiddy Bay to Pwll Strodyr (A. H. Cox). The ground is occupied by the under-mentioned beds, the strati- graphical order of which is, so far as known, as follows :— BauA . . . . . . Limestone of Hastern Quarry, Abereiddy = Mydrim Limestone of Carmarthenshire. LLANDEILO . . . . Lower Dicranograptus Shales = Hendre Shales of Carmarthenshire. Didymograptus Murchisoni Shales. Didymograptus Murchisoni Voleanics (including the ~) Abereiddy Ash, and Llanrian lavas). Didymograptus bifidus Shales. Tetragraptus Beds—dark slates. : Porth Gain Beds—grits and slates with Orthis calli- PAREN Gone vine rei ta ive gramma, var. proava. Abercastle Beds—sandy mudstones with Ogygia selwynt, etc. LLANVIRN ? gap. [xnvs ¢ Coch Beds—cleaved blue-black mudstones. DOUBTFUL AGE Ynys Castell Beds—siliceous mudstones and cherts. Ynys Castell grit and breccia. ? break. LINGULA Fuacs . . Flagsand laminated quartzites with Lingulella davisit. DOUBTFUL MENEVIAN. Slates near Abercastle with Agnostus sp. The ‘ Middle Llandeilo’ of Hicks’ classification has been found to include the Lower Dicranograptus Shales and the succeeding limestone ; that is, actually more than the Llandeilo formation as now defined. The ‘Upper Llandeilo’ includes various Lower Llanvirn and Arenig beds; the affinities of the other rock-groups are briefly discussed in the paper. lLingula flags occupy much of the adjoining inland district. References are made to certain ‘‘intrusive rocks and their relation to the adjoining sediments”. The detailed mapping of the area is now in progress. DECADE V.—VOL. X.—NO. X. 30 466 Reviews—Geological Survey of Great Britain. Part II. Pwll Strodyr to Pencaer (O. T. Jones). The following rock-groups are represented in probable descending order :— LOWER OR MIDDLE Pwll Deri Slates . . . Cleaved dark slates with ARENIG extensiform graptolites. 2? LOWER ARENIG . . AberbachQuartziteGroup Quartzites with thin dark probably equivalent to shales. the quartzites of Trwyn Llwyd and possibly of Pwll Strodyr. LINGULA FLAGS . . Mynydd Morfa Group. DOUBTFUL AGE . . PwllCrochan Group. . Dark slates with obscure fossils probably Mene- vian or Upper Lingula Flags. ?SontvaA . . . . . Llech Dafad Group . . Quartzites,greenand purple sandstones ; obscure fossils. The age and relationships of the various groups are briefly discussed, and reference is made to certain intrusive rocks which occur among the lower groups. In view of the great thickness of some of the groups and of the bearing of their age upon the igneous rocks of Pencaer and Strumble Head it is proposed to map the area in detail. RHVIEWwS. eS I.—Summary oF Proeress or THE GroLogicaL Survey oF GREAT Britain AND THE Muosrvum oF Pracricatn Grotocy For 1912. 8vo; pp. iv, 101, with 1 plate and 4 text-illustrations. London: printed for H.M. Stationery Office, 1918. Price 1s. N this memoir, as usual, there will be found much to interest all geologists, whether their special studies are among the Archean schists or on succeeding geological systems up to the time when Paleolithic Man occupied the country. In England and Wales field-work has been carried on in three districts: Denbighshire, Warwickshire and Staffordshire, and London with the south-eastern counties. In Scotland the districts comprise the West Highlands, North and Central Highlands, Kilmarnock in Ayrshire, and South Lanarkshire. Attention is called to the occurrence in Ben Armine Forest, Sutherland, of an altered peridotite, which is in contact with gneisses of Lewisian type and granite intrusions, and was probably intruded prior to the movements which caused the schistosity of the rocks. The subsequent remarkable effects of granitization are described. The mapping of some of the older Palzeozoic rocks on the western borders of the Denbighshire Coal-field has been revised, and it has been found that the Tarannon Shale does not rest unconformably upon the Ordovician, but that the Llandovery Beds are present, and no evidence Reviews—Geological Survey of Great Britain. 467 of unconformity locally exists. Some modifications have been found necessary in the groupings of the strata classed as Millstone Grit and Lower Coal-measures, and an unconformity has been proved at the base of the Upper Barren Coal-measures in the Denbighshire district. In Lanarkshire evidence of unconformity in the Millstone Grit has been observed. A large tract near Tamworth, regarded on the old geological survey maps as Keuper Sandstone, has now been ascertained to consist of the Keele Beds or Upper Red Coal-measures. Some questions concerning the upper limit of the Keele Beds have yet to be solved. Notes are contributed on the Lias and Cretaceous rocks of Mull (West Highland district), and particulars, illustrated by three maps, are given of the Tertiary igneous rocks. The discovery is recorded of numerous small hexagonal plates of blue corundum (sapphire), with other minerals, in an igneous matrix that consists of andesitic felsite and trachytic granophyre or syenite, with included blocks of _ baked sandstone and shale. In the London district the transitional clays, loams, and sands, between the mass of London Clay and the Lower Bagshot Sand, have been separately mapped as the ‘‘ Claygate Beds”. Descriptions are given of the glacial and later drift deposits in the various districts. In the Appendices there is a short article ‘‘On some Paleolithic Gravels near Swanscombe, Kent”, by Mr. Reginald Smith (of the British Museum) and Mr. Henry Dewey (of the Geological Survey). They give results of a careful personal study of the successive Pleistocene deposits in the Barnfield Pit, about half a mile north-west of Swanscombe Church. Here, resting on the Thanet Sand, the top of which is about 90 feet above O.D., is a series of gravels, sands, and loams, about 25 feet thick, that are usually described as forming the 100 foot terrace. For about three weeks the authors employed two gangs of men, and examined every spadeful of material dug away in order to ascertain the nature and sequence of the flint implements. Their results may be summarized as follows :— Upper Gravel . . Several flakes and one good implement, ‘‘ but further evidence is required as to the horizon.”’ Upper Loam . . Said to contain white patinated ovates. Middle Gravel . . More advanced forms, with one or two ovates of St. Acheul character. Palzolithic implements of Harly Chelles type. Lower Loam . . No implements. Lower Gravel . . Numerous flint flakes and some roughly cylindrical flints chipped at one end into a point or chisel-edge. Comparable with the Belgian type named after Strépy in Dr. Rutot’s system. It is regarded as not improbable ‘‘ that the Middle Gravel represents the whole of the Chelles period and the transition to St. Acheul”’. Records of borings at Lowestoft, Henlow in Bedfordshire, and Batsford in Gloucestershire, are communicated by Dr. A. Strahan. Those of Lowestoft and Batsford are speciallyimportant. At Lowestoft? 1 Boring commenced 1902, not 1912. 468 Reviews—Mines in the Lake District. the Chalk was proved to be 1,050 (possibly 1,055) feet thick; and it is interesting to note that at Norwich in Colman’s Well a thickness of 1,152 feet of Chalk was proved, but not quite the full local thickness, there being some 35 or 40 feet of Chalk in the bordering hills not passed through. The occurrence of 11 feet of Upper Greensand is also of interest, as this formation (6 feet thick) was also recognized in the Norwich boring. Below the depth of 1,627 feet at Lowestoft, beneath Gault and Lower Greensand, there were 205 feet of pale mudstones, regarded as ‘‘ Cambrian or Ordovician, probably the former”’. They yielded fragmentary remains of Lingula and Orbiculoidea. Water was obtained from the Lower Greensand, but the quality was medicinal. At Batsford, or Lower Lemington, near Moreton-in-the-Marsh, the boring was carried out in 1901-4 bya Coal Syndicate. Coal-measures were reached at a depth of 1,021} feet, but at the depth of 1,546 feet Silurian rocks were encountered. The Coal-measures were not of productive character, but it is possible that productive beds occur in the vicinity in proximity to Silurian rocks, as they do in the South Staffordshire Coal-field, Another article of practical importance is on ‘‘ The Copper Lodes of Inveryne and Kilfinan, Argyllshire”, by Mr. C. T. Clough. IIl.—Mines anp Minrne in THE (EneoutsH) Laxe District. By Joun PostierHwaite, F.G.S., Assoc. M.Inst.M.E. 38rded. 8yo; pp- xii, 164, with geological map, 15 plates, and 29 other illustrations. Whitehaven: W. H. Moss and Sons, Ltd., 1913. Price 3s, 6d. net. HE first edition of this work, issued in 1877, was favourably reviewed by John Morris in the Grorocrcat Magazine for 1878, p- 817; and a second and enlarged edition was published in 1889. In the present work much has been added, references being inserted to the later geological publications, together with lists of fossils and illustrations of a number of them. It would be well in a future edition to have the aid of a paleontologist in dealing with the names of species and the use of capital letters, etc. The main object of the work is, however, to describe the minerals and the mines, a practical and scientific subject with which the author is especially qualified to deal; and he has now added a considerable number of plans and sections of mines and veins, and some excellent views of quarries. Historical accounts of the coal-mining in Cumberland, and of the iron-mining in Cumberland and Furness, are given; and a synopsis of the State Papers relating to the mines in Newlands and the Smelting Works at Keswick (1547-80) has been appended. There is unfortunately no general index, and the illustrations are not systematically numbered; but the table of contents is full, and may suffice for the many who will appreciate the copious practical information. Reviews—The Calvert Boring. 469 TOU as Catvert Borine. f{\HE interesting and important record has now been published by Dr. A. Morley Davies and Mr. John Pringle (Quart. Journ. Geol. Soc., lxix, p. 308, 1913) on the strata proved in two deep borings at Calvert Station, on the Great Central Railway, in North Buckinghamshire. It exemplifies the need, expressed by Dr. Strahan in his Address to the Geological Society in February last, ‘‘ that registration of deep borings in a Government Department should be made compulsory.”” Readers of the Dazly Mail (October 18, 1911) will have been struck with the announcement, printed in bold type, of ‘‘ Coal within 50 miles of London’’, and with the advertisement of ‘‘ The Bucks Coalfields Syndicate, Limited”. It appears that the notion that coal occurred was based on the fact that inflammable gas, termed ‘ coal gas’, was encountered below depths of 380 and 448 feet. This was ‘‘ taken as an evidence of the possible existence at a shallow depth of a deposit of bituminous coal” ; and in some newspapers the statement was made that coal-seams had been struck at a depth of 5380 feet. The presence also of ‘‘ mottled red sandstone” was referred to as ‘‘very promising for coal at a shallow depth”. The mottled beds are now shown (in the paper above-mentioned) to be stained Tremadoc shales (Cambrian, 443 to 1,398 feet); and they are overlain directly by Lower Lias. It is suggested, however, that the staining might be due to a former covering of Triassic strata. The Calvert gas, which is stated to resemble that obtained from Wigan Cannel-coal, occurred below the base of the Lias, and Dr. Davies and Mr. Pringle mention as a possibility that the gas ‘‘ may have leaked into porous Triassic strata from underlying Coal Measures, possibly at some distance to the west or north-west’. IV.—DIFFrvusion IN RELATION TO THE STRUCTURE OF AGATES, ETC. EoLoGIscHE Dirrusionen. By R. KE. Lizszeane. pp. vii + 180, with 44 figures in the text. Dresden and Leipzig: Theodor Steinkopff, 1913. EOLOGISTS interested in the structure of agates, concretionary nodules, and similar objects, should not fail to read Dr. Liesegang’s extremely fascinating book. Recent chemical work on diffusion has thrown quite a novel light upon the possible cause of the markings characteristic of such structures, but may not be generally known to geologists, because some of the journals in which many of the original papers appeared do not usually circulate among them. The author has therefore done excellent service by bringing together the somewhat scattered literature on the subject, and showing how closely the results obtained in the laboratory parallel the phenomena actually met with’ in nature. A valuable and important feature of the book consists of the extensive series of experiments on diffusion which is interwoven in the text to illustrate the particular points dealt with. The salts and materials used in them are all easily procurable, and the careful explanations render it easy to repeat any of the experiments. The scope of the book is comprehensive in character. It opens 470 Reviews—Determinative Mineralogy Tables. with a discussion of diffusible substances, the geological media which admit of diffusion, and the general characters of diffusion; the various types of structure are then treated in detail. The author shows that diffusion has been responsible, moreover, for the alterations that have sometimes occurred in ore-deposits, and for the formation of certain pseudo-fossils, such as, for instance, the once famous Zozoon canadense. Two indices, of names and subjects, which bring the book to a close, add to its usefulness. V.—DererMinativE Mrineratocy wire Tastes. By J. Votney Lewis. 8vo; pp. v-+151, with 68 figures in the text. New York: J. Wiley and Sons, 1913. Price 6s. 6d. net. fI\HIS book is designed to meet the needs of students and of mining engineers, and treats not only of minerals of economic importance but also of many of the rarer species; altogether 380 minerals are included. In the text we find a brief account of the apparatus, reagents, and methods to be used in ‘ wet’ and in ‘ dry’ tests, and of the principal reactions of the elements. The simple forms of crystals are enumerated and illustrated by fifty-seven figures of various minerals; for an explanation of the face-indices and for other details the reader is referred to textbooks. There is a good glossary of technical terms, and a table of the elements with their atomic weights. The tables are based very largely on those of Brush and Penfield, but are modified and much condensed; the relative importance of the minerals is indicated by the type in which the names are printed. The determinations are made to rest almost wholly on chemical tests, and no mention is made of the optical properties of minerals. Tables for the determination of rock-forming minerals, on the other hand, commonly neglect the chemical and appeal only to the physical properties. Now that the optical properties of so many minerals are well established, and the use of the petrological microscope has become so widespread, a combination of the two types of tables should be quite possible, and any determinative mineralogy which does not seek to combine the two must be considered a little behind the times. W: Cee VI.—Unirep Starts Grotoaicat SURVEY. 1. Buttery 502. THe Eactr River Reeton, Sourn-HastErn ALASKA. By Avotra Knorr. pp. 61, with 3 figures in the text and 5 plates (including 3 maps). 1912. ee area, which has been mapped on the 1 inch scale, embraces a third of the Juneau gold belt of South-Eastern Alaska. Three large glaciers come down from the Coast Range to within 100 feet of sea-level: they are shown to be retreating. There is evidence that at one period the country was glaciated to 3,400 feet above sea-level, the main ice-stream flowing south-east down the Lynn Canal. The absence of hanging valleys supports the idea that Reviews—The United States Geological Survey. 471 the fjords of this area are due, not to glacial erosion, but to the drowning of a drainage system only slightly modified by glaciation. The whole of the' area between the Coast Range and the coast is occupied by a group of slates and greywackes known as the Berners Formation, probably of late Mesozoic age. These are intercalated with volcanic breccias, tuffs, and augite melaphyres. The Coast Range itself consists of quartz-diorite, which is regarded as of late Cretaceous age. The slates become metamorphosed into schists in the neighbourhood of the quartz-diorite, which. itself is markedly gneissose at its margins. The gold belt is contained wholly within the slates; there are no prospects in the schists or in the quartz-diorite. Ore-bodies occur either as stringers, fissure veins, or occasionally as mineralized dykes. "The dykes belong to a group of minor intrusions of uncertain age, and include diorites, albite diorites, lamprophyres, and gabbros. Their _ mineralization usually takes the form of intense albitization. Another frequent result is the production of abundant apatite in the altered wall-rocks. Some of these mineralized dykes carry low- grade gold ores, which indicates a magmatic origin for the gold deposits in this area. Pillow-lavas are recorded at one locality, and their occurrence in an area in which albitization is so prominent a feature would suggest affinities with the spilitic facies. However, the pillow-lavas appear to consist of augite with only a little interstitial material of low refractive index and to belong to the augite melaphyre series of the Berners Formation, whereas the albitization takes place in dykes probably younger than the quartz-diorite of the Coast Range. The bulletin contains details of the gold prospects in the area, and the geological work has done much to show in what directions fresh ore-bodies should be sought. _ 2. Butietin 503. ITkron-orze Deposits or tHE Kacte Movunrarns, Catirornia. By EH. C. Harper. pp. 81, with 4 figures in the text and 13 plates (including 6 maps). 1912. ITUATED in the waterless desert of South California, and some 40 miles from the nearest railway, the Eagle Mountains had been visited only by hasty prospecting parties until the district was surveyed in 1909. This survey located deposits of very pure iron-ore, and it is estimated that about fifty million tons of good ore are available in the northern part of the range. It is thought that the establishment of blast furnaces and steel plants in South California will have for its immediate result the development of these Eagle Mountain ores. The geological structure of the northern part of the range is that of an ovaldome. The centre is occupied by a small outcrop of gneiss and schist ; these are surrounded by a series of quartzites and schistose arkose, overlain by a second quartzite with interbedded dolomite lenticles. Into these beds two large sills of quartz-monzonite have been intruded, causing the metamorphism of the quartzites and dolomite. It is in the dolomite horizons and in the surrounding 472 Reviews—The United States Geological Survey. rocks that the iron-ores have been formed. Five types of deposit are recognized: (1) beds and irregular masses of hematite representing nearly complete replacements of dolomite ; (2) layers of hematite in crystalline dolomite; (3) small replacement deposits in sediments at the contact of minor quartz-monzonite intrusions; (4) veins in quartzite; and (5) veins in quartz-monzonite. The first type includes quite 80 per cent of the ore in the district. The ore is now in the form of hematite, but the occurrence of pseudomorphs shows that magnetite and pyrites were the original minerals formed by the replacement. A consideration of the ore-bodies and of the associated rocks shows that they result from the replacement of dolomite by ore-bearing solutions of deep-seated origin: the replace- ment followed the intrusion of the quartz-monzonite sills, but it preceded certain minor intrusions of aplite, quartz-diorite, and soda- syenite-porphyry. No fossils having been found, nothing is known of the precise age of the quartzites or of the periods at which the intrusions took place. 3. Burren No. 530 (1913) consists of ‘‘ Contributions to Economic Geology (Short Papers and Preliminary Reports). Part I.—Metals and Non-metals except Fuels’. Part II, on ‘Mineral Fuels”, was noticed in the Grotogrcat Magazine for July (p. 322). In the work before us there are reports on gold, silver, copper, lead, zinc, iron, manganese, aluminium ores, and on some rare metals such as vanadium, carnotite, etc. There are notes and bibliographies on clays, fuller’s earth, building stone, gypsum, glass- sand, asphalt, abrasive materials, phosphates, mineral paints, sulphur, graphite, ete. Bulletin No. 537 (1913) is on ‘‘ The Classification of the Public Lands”’, by Mr. George Otis Smith and others. It contains accounts of the laws relating to agricultural, mineral, coal, and other lands; and of the methods of classification of lands and their valuation in reference to various minerals, water-power and reservoir sites, public water reserves, ete. It should furnish useful information and suggestions to the many owners and land-surveyors now concerned in this country in the valuation of estates. 4. Warer-suppty Paper No. 259 (1912), by Messrs. M. L. Fuller and F. G. Clapp, deals with ‘‘The Underground Waters of South- Western Ohio”’, containing a general description of the topography and geology, and special accounts of the geology and water prospects of each county. The chemical character of the waters is discussed by Mr. R. B. Dole, who considers the suitability of various waters for domestic, industrial, and medicinal purposes, likewise the physical qualities of waters, the suspended mineral matter, the growths of microscopic plants, and the questions of purification and softening. No. 293 (1912) is on the ‘‘ Underground Water Resources of Iowa’’, a voluminous report separately printed also by the lowa Geological Survey (see Grot. Mae. 1913, p. 226). No. 297 (1913) consists of part ii1 of a ‘‘Gazetter of Surface Waters of California”, by Mr. B. D. Wood, dealing with the Pacific coast and Great Basin streams. No. 300 (1913), by Messrs. H. D. McGlashan and H. J. Dean, is on the ‘‘ Water Reviews—Geology of Western Australia. 473 Resources of California”, comprising part 111 of Stream Measurements. No. 310 (1913), by Messrs. F. F. Henshaw, H. D. McGlashan, and K. A. Porter, is on the ‘‘ Surface Water Supply of the United States’’, being part x, on the Great Basin; and No. 311 (1912), by Messrs. McGlashan and R. H. Bolster, is on the same general subject, being part xi, on the Pacific coast in California. No. 313 (1913), by Messrs. Henshaw and G. L. Parker, is part 11 of a report on the ‘‘ Water Powers of the Cascade Range’’, wellillustrated by maps and diagrams. No. 316 (1913) is a brief account of the ‘‘ Geology and Water Resources of a portion of South-Central Washington”’, by Mr. G. A. Waring, who describes the physical features, geology, and agriculture, with accounts of the springs, wells, and systems of irrigation. VIl.—Gzonogicat Survey or Western AUSTRALIA. ULLETIN No. 42 (1912) comprises ‘‘ Contributions to the Study of the Geology and Ore-deposits of Kalgoorlie, East Coolgardie Goldfield”, part i, by Messrs. E. 8. Simpson and C. G. Gibson. The geological structure of the area is described by Mr. Gibson, who states that the original rocks were shales, sandstones, grits, and con- glomerates, with possibly interbedded lava-flows, that were deposited probably in pre-Cambrian times on a gneissic or granite floor. The strata were afterwards tilted into highly inclined positions and subsequently invaded by gabbros, diabases, porphyrites, pyroxenites, peridotites, etc. Still later there were intrusions of quartz- and felspar-porphyries, and further earth-movements that gave rise to shearing and faults. Along the shear-planes the auriferous lodes are developed. Accounts are given of the various rocks and mode of occurrence of the ore-deposits. Mr. Simpson then describes the mineralogy of the ore-deposits, the surface and underground waters, and the telluride ores in particular. In a prefatory note the Government geologist, Mr. A. Gibb Maitland, remarks that the results of the researches indicate the probability that the whole of the ore-deposits are likely to persist to the greatest depth to which mining is possible, and that the grade of ore below 2,000 feet may be expected to be as variable as it is above that level. The memoir is well illustrated by maps, views, and microphotographs. VIII.—Coneo. AnnatEs pv MusEe pu Coneo Beter. Géologie, sér. m1, tom. i, fase. 1: La Faune paléocéne de Landana. Par Vincent, Dotto, et Lericue. 4to. Bruxelles, 1913. LTHOUGH the existence of these Tertiary beds has been known since 1877, this is the first time their contents have been systematically described and figured. Pechuel - Loesche (1877), @ Andrade (1904), and others have visited the neighbourhood, but beyond fish-remains and some casts of Mollusca few recognizable fossils seem to have been found. The present series have been obtained by M. Diderrich, and show a definite Lower Eocene or passage to Cretaceous facies. The fossils occur in blocks of compact white limestone, recalling white chalk of varying consistency, and 474 Reviews—Geology iw Northern Assam. are nearly always in the state of casts, the moulds of which retain quite sharply the impression of the ornaments of the shell surface, much the same as in the case of the English fossils from the Chalk Rock. M. Vincent describes the Mollusca, M. Dollo Podocnemis congolensis, and M. Leriche some new fishes, Hypolophites mayombensis, Myliobatis dispar, and a couple of Agassizian species of Zamna and Odontaspis. Leriche also gives a sketch of the Eocene fish fauna of the west coast of Africa, which confirms the opinion that the general fauna is of early Eocene age. The papers are well illustrated. IX.—GeronocicaL Expnorations rin NortHern Assam. The Records of the Geological Survey of India, vol. xlii, pt. iv, 1912, contains accounts of two traverses made by geologists accompanying punitive expeditions against the hill tribes of Northern Assam. KE. H. Pascoe, M.A., gives an account and sketch map of ‘‘A Traverse across the Naga Hills of Assam from Dimapur to the neighbourhood of Sarameti Peak”’. The traverse is joined up with earlier mapping by Hayden further to the north. Near Dimapur the Tertiaries are represented by the Tipam sandstones. These are bounded on the east by a reversed fault, bringing in the sandstones and carbonaceous shales of the Disang Series. There is a band of serpentine, derived from gabbro and peridotite intrusions probably of pre-Disang age. The Chimi conglomerate forms an important horizon as it separates the Disang Beds to the west from the Makwari Beds to the east; these latter differ from the Disang Series only in the degree of their metamorphism, which increases eastwards. Blue slates of good roofing quality occur in the Tepe and Tuzu Rivers. The entire absence of limestone between the Tipam Beds and Sarameti Peak is notable. Correlation with other areas is difficult ; provisionally the Disang Series is correlated with the Negrais, and the Makwaris with the ‘ Axials’ of Burma. J. Coggin Brown, M.Sc., accompanied the Abor Expedition of 1911-12. The geological results of this expedition are given in “A Geological Reconnaissance through the Dihong Valley”. This was practically untouched ground, and the traverse adds considerably to our knowledge of the mountains bordering Upper Assam. After leaving the alluvial deposits near the mouth of the river, the road crosses Pleistocene gravels resting on Siwalik sandstones containing fragments of lignite. These Tertiary beds are succeeded by carbonaceous shales and quartzites of Gondwana age, associated with a large series of basalts—the Abor Volcanic Series. The junction between Siwalik beds and Gondwanas is probably an overthrust. Above the Gondwanas the route traverses a large series of slates, phyllites, and dolomites, comparable with the Daling and Baxa Beds of the Darjeeling area. These are followed by true mica-schists. There is frequent repetition of similar groups of rocks, which is due to the existence of closely-packed sinuous folds, often overfolded, and having a general N.E. and 8.W. trend. Little of economic value was found, the coal being too inaccessible to pay for the working. Correspondence—A. R. Hunt. 475 X.—Brier Notices. 1. Tue Hits Basty.—Dr. H. von Koenen discusses the disturbances of the Hils Basin in the Jahresb. Niedersiich. geol. Ver. Hannover, 1913. He describes it as ‘‘a basin due to compression, with uptilted margins, its interior being filled with essentially younger beds less strongly influenced by the pressure ”’. 2. Waters or Kaarea.—Mr. G. W. Grabham has published in the Cairo Scientific Journal (No. 61, vol. v, October, 1911) a paper dealing with the mechanics of wells, the choking of boreholes by deposition, and the exhaustion of strata. This is a reply to Mr. H.J. L. Beadnell’s paper, and the whole discussion is interesting and instructive. CORRESPON DEHN CHE. A SUPPOSED SUBMERGED FOREST IN SOUTH-WEST SCOTLAND. Srr,—In your review of Mr. Clement Reid’s book on submerged forests you cite the statement that in ‘‘ Scotland the Neolithic deposits seem to be raised beaches instead of submerged forests’’. There is what appears to be a submerged forest bed in a small creek called Brighouse Bay, a little west of the estuary of the Dee on the coast of Galloway. It was incidentally noticed in a paper published by the Society of Antiquaries of Scotland in 1875. Some presumably large antlers of (red) deer were recorded as from the ‘‘ submerged forest”’. The district is outwardly much like that of South Devon, viz. with low-level beach-platforms, drowned valleys, and what seem to be submerged forest clays. The paper referred to is on the exploration of the Borness Cave, and the mention of the submerged forest is on p. 11 of the reprint. The late Mr. A. J. Corrie and myself were solely responsible for the geological part of the report, and we were guided by the South Devon raised beaches in our identification. It is quite possible we were mistaken. Perhaps some of our readers may be acquainted with Brighouse Bay. Wanye ae TORQUAY. September 8, 1913. NOTE ON THE NAME ‘CHARMOUTHIAN’. Srr,—D’Orbigny in 1852 divided the Lias into three stages which he called respectively the Sinemurian, the Liassian, and the Toarcian, and in 1864 Mayer-Eymar proposed the name ‘Charmouthian’ to take the place of d’Orbigny’s Liassian. As pointed out by Mr. W. D. Lang in this Magazine (1912, p. 284), this middle stage of d’Orbigny and Mayer-Kymar included more than has usually been assigned to the Middle Lias in England. I am not now concerned with the grouping of the zones, but with the form of the name which has been adopted by most French geologists in preference to the Pliensbachian of Oppel. The name is, of course, taken from the little town of Charmouth in Dorset, near which the Middle Lias is well exposed in the cliffs, but it is unfortunate that Mayer-Eymar should have tried to latinize such a name as Charmouth without making any inquiry as to its ancient form. It is a recognized custom or rule that when such names are 476 Correspondence—A. J. Jukes-Browne. derived from those of places or districts they are based on the Roman name if there was one, or on the earliest known form of the name. I am informed by Dr. H. C. March, F.S.A., that Charmouth is generally believed to be the place called Carrum in the Anglo-Saxon Chronicle, which records a battle fought there by King Egbright against the Danes in a.p. 838, and this seems to be the earliest mention of the place, which was never a port of any importance. All the editors and commentators identify Carrum with Charmouth, and it is this ancient form of the name which should be taken as the basis of a stratigraphical term and not the uncouth modern name of Charmouth. I think, therefore, that if our French colleagues continue to use a name taken from this place they should substitute Carrumian for Charmouthian, on the same principle that we write Callovian, not Kellawaysian; Bajocian, not Bayeuxian; and Cenomanian, not Lemansian. PS.—Since the above was written and printed Mr. Lang has proposed the name ‘ Carixian’ for the lower part of the Charmouthian or Pliensbachian stage, accepting Bonarelli’s name of Domerian for the upper part, and he derives this name from ‘‘the Carixa of Ravennas”’, which is cited in Roberts’ History of Lyme Regis as the ancient name of Charmouth (see Gror. Mac., September, 1913, pp. 401-12). On this proposal I have several criticisms to offer. In the first place, Mr. Lang remarks that he has ‘‘ already advocated the propriety of employing the term Charmouthian strictly with its original connotation’, and yet he suggests as a new name for a part of this Charmouthian a term taken from what he accepts as the Latin name of the same place. Surely if Carixa was the Roman name for Charmouth it should be used as the basis for the name of the whole Charmouthian stage. Secondly, the “ Chorography of Ravennas” is not a very good authority ; its author is really unknown and even the date of it is somewhat uncertain. Moreover, as Mr. Lang himself points out, the name Carixa is probably a latinization of the Celtic words car-isea, meaning the River Char, not the place. As a matter of fact, it is very doubtful whether there was any settlement at the mouth of the Char until the time of the wars between the Saxons and Danes. Thirdly, we seem in danger of being saddled with too many of these latinized names. They are very useful as names for stages, but when it comes to introducing sub-stages with similar names I for one protest. ‘The division of a system into two or more series, of a series into stages, and of a stage into any number of zones seems quite sufficient for practical purposes. The addition of sub-stages merely imposes an unnecessary burden upon the memory. In England the stages of the Lias have hitherto been called Lower, Middle, and Upper. ‘Te it is thought more convenient to divide the series into four or five stages, let us have geographical names for them, but there is no good. reason for burdening our nomenclature with a double set of such names. A. J. Juxes-Browne. TORQUAY. September 8, 1918. Obituary—Srr George Howard Darwin. ATT THE LATE HERBERT KELSALL SLATER. Srr,—I am informed by Dr. W. F. Smeeth, the principal officer of the Geological Department of Mysore, that a fund is being formed to make some provision for the family of Mr. H. K. Slater of that department, who died recently from the bite of a large Russell’s viper while engaged in Geological Survey work in the Shimoga - District. An obituary, in which his services to geology are recorded, appeared in this Magazine in July last. He leaves three young children almost entirely unprovided for, and it is urgently necessary to raise a sum sufficient for their upbringing and education. Contributions may be sent either to Dr. W. F. Smeeth, Bangalore, India, or to me at the address below. Joun W. Evans. IMPERIAL INSTITUTE, LONDON, S.W. OBITUARY - SIR GEORGE HOWARD DARWIN, KC AB Me AS GBs Disc: A ShES: Born JuLy 9, 1845. DIED DECEMBER 7, 1912. In his opening Address to the British Association the President, Sir Oliver Lodge, writes (Birmingham, September 10): ‘‘ Through the untimely death of Sir George Darwin the world has lost a mathe- matical astronomer whose work on the tides and allied phenomena is a monument of power and achievement. So recently as August, 1905, on our visit to South Africa, he occupied the Presidential Chair.” It was on his return to England after his visit to South Africa that he received the honour of Knight Commander of the Bath from His Majesty. The second son of the late Charles R. Darwin (author of The Origin of Species, etc.), George Darwin was born at Down, Kent, in 1845, and was educated privately by the Rev. Charles Pritchard (later Savilian Professor of Astronomy at Oxford). He entered Trinity College, Cambridge, in 1864, and graduated asa Second Wrangler and Smith’s Prizeman in 1868, and in that year he was elected to a Fellowship at Trinity College, which he held 1868-78, and to which he was re-elected in 1884. At first he studied the law, and was called to the Bar in 1874, but returned to Cambridge, where he spent the rest of his life, devoting himself to Solar Mathematics. His Collected Papers, which form four volumes, were recently published by the Cambridge University Press. In 1884 he was chosen Plumian Professor of Astronomy in Cambridge. Sir George Darwin’s writings had a most important bearing on Dynamical Geology, especially ‘‘ On the influence of Geological Changes on the Earth’s Axis of Rotation’? (Phil. Trans., 1877), “On the bodily Tides of viscous and semi-elastic Spheroids and on the Ocean Tides on a yielding Nucleus” (op. cit., 1879), ‘‘ On the Precession of a viscous Spheroid and on the Remote History of the Earth” (op. cit., 1879), and ‘‘On the Secular Changes in the 478 Obituary— Tempest Anderson. Elements of the Orbit of a Satellite revolving about a Tidally Distorted Planet” (op. cit., 1880). Another of his memoirs may be appropriately recalled, bearing upon the same subject as that recently dealt with by Colonel Burrard (Got. Mag., September, 1913, pp. 385-8) and the Rev. O. Fisher: ‘< On the Stresses caused in the Interior of the Earth by the Weight of Continents and Mountains ”’ (op. cit., 1882). In 1877 George Darwin became acquainted with Lord Kelvin, who from that time took a warm interest in all his work and greatly influenced his subsequent researches. In 1884 he married Maud, daughter of Charles du Puy, of Philadelphia, and leaves two sons and two daughters. His eldest son, Charles, was a scholar of Trinity in 1905, and graduated as Fourth Wrangler in Mathematics in 1909. Sir George delivered a course of lectures at Boston, U.S., in 1897 under the title of ‘‘The Tides”’, which was subsequently printed as a popular volume entitled Zhe Tides and Kindred Phenomena of the Solar System (1898). He was a Vice-President of the International Geodetic Association, a member of the Meteorological and Solar Physics Committees, Doctor of nine Universities, Foreign Honorary Member of twenty Societies and Academies, and Foreign Correspondent of twelve others. He served as a member of Council of the Royal Society for seven years, and as Vice-President for two years, and was President of the Cambridge Philosophical Society and Vice-President of the Astro- nomical Society. Sir George Darwin was also the recipient of the Royal Astronomical Gold Medal in 1892, Royal Medal, Royal Society, in 1884, and the Copley Medal in 1911, and several others. TEMPEST ANDERSON, M.D., D.Sc., F.G.S. BORN 1846. DIED AUGUST 26, 1913. Tur death is announced from enteric fever whilst on his voyage home from the Philippine Islands of Dr. Tempest Anderson, of York. The son of the late Mr. William C. Anderson, M.R.C.S., a member of an old and well-known Yorkshire family, Dr. Tempest Anderson was born at York in 1846. He was educated at St. Peter’s School, York, and had a distinguished student’s career at University College, London. He was a well-known scientist. As President of the Yorkshire Philosophical Society he spent a great deal of time and much money in its interests, and it was through his influence that a new lecture hall was recently added to the York Museum. Dr. Anderson’s special branch of study was volcanic phenomena, and this subject, illustrated by photographs, he brought on many occasions before the British Association. He was author of Volcanic Studies in Many Lands, 1903 (see review by W. H. Hudleston, Guor. Mac., 1903, p. 160). After the terrible eruption in May, 1902, of the Soufriére, in St. Vincent, one of the West India Islands, he and Dr.J.8. Flett were commissioned by the Royal Society to investigate the matter. Their joint report was published in the Philosophical Transactions for 1903. Dr. Anderson revisited the West Indies in 1907, and gave an account Obituary— Wiliam Henry Sutcliffe. A79 of the subsequent changes in the volcanic districts of St. Vincent and Martinique, his report being published in 1908. Dr. Anderson was Tyndall lecturer on volcanoes at the Royal Institution. Pro- fessionally he was a specialist in diseases of the eye. He took a deep interest in the promotion of open spaces and garden cities. He was an extensive traveller, and there were very few places where volcanic eruptions were known to have occurred that Dr. Anderson had not visited. He was a noted Alpine climber and photographer, and had produced some splendid views of places of interest which he visited during his travels. Among the numerous appointments and distinctions which he held were the following: Consulting ophthalmic surgeon to the York County Hospital; Fellow of University College, London; member of Council and former Vice- President of the British Association; President of the Museums Association, 1910; and member of the Council of the Geological and Royal Geographical Societies. Dr. Tempest Anderson was one of the five original Trustees! of the ‘Sladen Fund’ established by his sister, Mrs. Walter Percy Sladen, F.L.S., for the advancement of scientific research in Anthropology, Zoology, Botany, and Geology. Dr. Anderson was unmarried.? WiLIAM HENRY SUTCLIFFE, F.G.S. BORN SEPTEMBER 25, 1855. DIED AUGUST 18, 1913. W. H. Surctirre was born at Ashton-under-Lyne, educated at Manchester Grammar School and Owens College (now Manchester University). Trained for the cotton trade, he was for some time manager of a cotton-mill near Rouen. In 1885 he became manager for Messrs. E. Clegg & Sons’ cotton-mills at Shore, Littleborough, near Rochdale, Lancashire, and subsequently became one of the managing directors. The firm is one of the largest cotton manu- facturers in the district and employs about 1,500 workpeople. Apart from his business Mr. Sutclitfe was best known as a geologist and archeologist and a member of many scientific societies. He early took an interest in the remains of primitive man found on the hills in the neighbourhood of Rochdale, and the fruits of his labours and that of other workers are to be seen in the fine collection of flint implements and other remains in the cases of the museums at Rochdale and Manchester University. One of his most interesting contributions was a joint paper with Mr. W. A. Parker, F.G.8., on ‘‘ Pigmy Flints, their provenance and use’’, in which they almost conclusively proved that the use of these minute flints was as skin-scrapers. He also communicated a paper to the Manchester Literary and Philosophical Society on March 18 last, on ‘* A Criticism of some Modern Tendencies in Prehistoric Anthropology”. This‘was an admirable study of recent theories as ' Dr. Tempest Anderson, F.L.S., F.G.S.; Henry Bury, M.A., F.L.S., ete. ; Professor Herdman, F.R.S.; T. Bailey Saunders, M.A.; and Dr. Henry Woodward, F.R.S. ? For many of the above particulars we are indebted to the Morning Post, August 29, 1913. 480 — Obituary— William Henry Sutcliffe. to the antiquity of man, and wasa careful weighing and sifting of the evidence in connexion with some of the discoveries of recent years. He strongly attacked the theory that the so-called ‘Koliths’ were the work of man, and also the idea that the Galley Hill skeleton found some years ago in Kent and the one found near Ipswich were of very early type, and for this object he visited Ightham, Kent, and the locality where the Ipswich skeleton was found. As a geologist he has been the means of considerably extending our knowledge of the paleobotany of the Lower Coal-measures ; and the ‘Bullion Mine’, Shore, near his residence, has become widely known on account of the rich harvest it has yielded of specimens new to science, and his name has been commemorated in Zudicaulis Sutcliffed and in Sutelifia insignis. He has also been associated with other well-known local geologists in the discovery of the very rich fauna in the Middle Coal-measures at Sparth, Rochdale, about which Dr. H. Woodward gave a paper at the British Association Meeting at York in 1906, when he named a new species of fossil arachnid, Geralinura Suteliffer, and this specimen with many others have been presented by Mr. Sutcliffe to the Geological Department of the British Museum (Natural History). Most of his holidays in recent years have been devoted to geological investigation, and he invariably returned with many valuable specimens, some of which have enriched the Rochdale and Manchester Museums. One of his recent finds was a fine specimen, 20 feet long, named Plesiosaurus homospondylus, from the Lias of Saltwick Bay, : near Whitby, which is preserved in the Manchester Museum. In one of his archeological investigations he endeavoured to trace the Roman Road over Blackstone Edge (Pennine Range) north-east of Rochdale, and had a large portion of ground uncovered beneath the turf and heather so as to trace its course for a considerable distance. Mr. Sutcliffe was elected a Fellow of the Geological Society in 1908, and contributed a joint paper to that Society in 1904 on Hoscorpius sparthensis, sp. nov. (Quart. Journ. Geol. Soc., vol. 1x, p. 394). He was a member of the Manchester Geological Society and University Geologists’ Association, the Manchester Literary and Philosophical Society, and many other bodies. He was also a member of Council of the Manchester Museum. He joined the Rochdale Literary and Scientific Society in 1886, became a member of Council in 1898, and was last year elected President, when he gave a very interesting address on ‘‘The Evolution of Tools’’, to illustrate which he had on exhibition about 500 specimens, showing the development of the principal form of tools demonstrating the evolution of the textile industry. He had a large circle of English and foreign friends amongst men of science, including the Editor of this Magazine. Mr. Sutcliffe was in private life and in his scientific pursuits one of the kindliest and most genial of men. For some months he had been in failing health, and died at Weymouth on August 18 last, to the deep regret of his many friends. He leaves a wife, one son, and two daughters to mourn his loss. S. Si-Pip Was BRITISH MUSEUM (NATURAL HISTORY) NEW PUBLICATIONS. : Catalogue of the Collection of Birds’ Eggs in the British Museum (Natural History). Vol. V. Carinatz (Passeri- formes completed). By W. R. Oainvin-GRant. 8vo. pp. xxiii, 547, with 22 coloured plates. Cloth. £2 7s. 6d. Catalogue of the Chzetopeda in the British Museum (Natural History). A. Polycheta.—Part I: Arenicolide. By J. H. AsHwortH. Roy. 8vo. With 15 plates. Cloth. 27s. 6d. MILLER (G. S.). Catalogue of the Mammals of Western Europe (Europe exclusive of Russia) in the Collection of the British Museum. 8vo. pp. 1034, with illustrations. Cloth. 26s. History of the Collections contained in the Natural History Departments. Vol. II: Appendix, Zoology, 1856 to 1895. By Dr. A. GuNTHER. 8vo. pp.118. Cloth. 5s. A Descriptive Catalogue of the Marine Reptiles of the Oxford Clay, based on the Leeds Collection in the British Museum (Natural History). 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British Association : Caleareous Algse at certain Geo- logical Horizons, with Special Reference to the Paleozoic Rocks. By Professor E. J. GARWOOD, M.A., V.P.G.S. (Continued.)... The Plutonic Rocks of Garabal Hill. By B. K. N. WYLLIE, M.A., B.Se., and ALEXANDER Scorr, M.A., B.Sc. (With two Text- ficures. ) ee 499 On Saturated and Unsaturated Igneous Rocks. By Professor S.J.SHAND,D.Se.,Ph.D.,F.G.S. 508 Septaria: a Defence of the ‘Shrinkage’ view. By T. CRoox, ReREC@ Se), EGSeencc sss LONDON : 490 .- 514 South-West Texas. By T. O. Papers read in the Geological BOSWORTH, D.Sc., B.A., F.G.S. Section phir Sede aie ene (Plates XVI and XVII.) .. . 481 The ‘Twelfth International Geo- Ill. REVIEWS. ae ee TE CUSCL, ’ 486 Geology of the Newton Abbot = District. By W. A. E. Ussher On the Important Part played by amd others... : ey DULAU & a Lxp., 387 Geology and Forestry ... ... ... 526 Annual Report of the; ‘Britighs)) Lae Museum .. . Doe at United States cash Survey (Water- Supply) sha NEEDY rt & IV. MISCELLANEOUS. Dr. F. H. Hatch, F.G¢4 34, resident, seo < elect of Institution of 3 snihe-and Metallurey . : - 528 Drstiseb's Sibly, F, G. 'S., ‘transferred Z to Cardiff from King’s College ... 528 Mr. T. Sheppard, F.G.S., President- elect of Yorkshire Naturalists’ Union ... ... 528 SOHO SQUARE, W. ce _ > The Volume for 1912 of the GEOLOGICAL MAGAZINE is ready, price 26s. net, Cloth Cases for Binding may be had, price ls. 6d. net. NOW_READY. Three Quarto Volumes of about 400 pages each, small 4to, and an Atlas of 66 pages of maps in colours, 13% X 19%, bound in heavy paper cover. Price £5 5s. per set net. THE COAL RESOURCES OF THE WORLD. An Inquiry made upon the initiative of THE EXECUTIVE COMMITTEE OF THE TWELFTH INTERNATIONAL GEOLOGICAL CONGRESS, CANADA, 1913, with the assistance of GEOLOGICAL SURVEYS & MINING GEOLOGISTS OF DIFFERENT COUNTRIES. Edited by the GEOLOGICAL SURVEY OF CANADA. With numerous Plates and Illustrations in the Text, and accompanied by an Atlas of 66 pages of maps in colours. The work is well illustrated with figures, maps, etc., but in addition to these text-illustrations there is an atlas of 66 pages of maps in colour showing the distribution of the coal areas and the geology of the more important fields. Sole Agents for Great Britain: DULAU & CO., Ltd., 37 Soho Square, London, W. nee Grou. Mae. 1913. IRA) CXOVale T. O. Bosworth photo. Vegetation and arid Surface-features in South-West Texas. GHOLOGICAL MAGAZINE NEW SERIES. DECADE Vin VOLE. ox. No. XI.—NOVEMBER, 1913. ORIGINAL ARTICIAS. ——— I.—Norrs on tHE Semr-Arrp Conpirions in A Part oF SouTHERN Au EXAS. By T. O. BoswortH, D.Sc., BAe F.G.S. (PLATES XVI AND XVII.) Introduction.—The conditions described below were observed over ’ a large part of South-West Texas; but the local details apply to an area of one or two hundred square miles in McMullen County, geologically surveyed by the writer in 1912. The centre of observations was a little mining ranch named Crowther, about 50 miles south of San Antonio and 80 miles from the Gulf of Mexico, near the inland limit of the Gulf coastal plain. The country for many miles around Crowther is practically untouched by man, though a somewhat primitive little local railroad now under reconstruction reaches to within 16 miles of it. Geological Structure of the Region.—The coastal plain is, say, about 100 miles wide, extending along the coasts of Louisiana, Texas, and Mexico. The strata are very slightly inclined towards the sea and strike approximately parallel with the coast. Apparently there has been a gradual recession of the sea, accompanied by a slight uptilting of the land, so that the Quaternary and latest Tertiary were not deposited far inland. Near the coast the plain is nearly flat and almost at sea-level. Inland the ground rises, imperceptibly at first, and then by successive gentle steps. Towards the inland limits of the plain there has been considerable denudation, and the rocks are well exposed. Continuing through this more rocky country, at length we reach the block-faulted Cretaceous beds beyond the plain. In the area considered, the United States Government has not yet carried out either its geological or topographical survey, but bulletins and maps have been published dealing with one or two other portions of the plain.’ Climatic Conditions.—From east to west along the coastal plain, there is a gradual change in climate, the Louisiana and South-East Texas end being moist, whilst the South-West Texas endisdry. The rainfall in McMullen County is about 22 inches, and most of it falls 1¢. W. Hayes & W: Kennedy, ‘‘ Oil Fields of Texas—Louisiana Gulf Coastal Plain’: Bulletin B 212, United States Geological ae DECADE V.—VOL. X.—NO. XI. ! 31 482 Dr. T. O. Bosworth—Arid Conditions in S.W. Texas. quickly within a few weeks of the spring. The mean temperature exceeds 80° F. throughout the three summer months, but it is not much above 50° F.in January. ‘The air is very clear, and mirages are visible in summer and autumn. ‘The wind blows almost constantly in from the Gulf, and often is very strong, causing sand- storms. At times there is a sudden fall in temperature brought about by a cold wind from the North, known as a ‘ Norther’, which oceasionally attains to the violence of a mild hurricane. Geology and Topography around Crowther.—Around Crowther the high ground (about 700 feet above sea-level) is a steep dissected escarpment or plateau, with bluffs sometimes nearly 100 feet high and outliers in the form of table-like hills. ‘The high ground is capped by a series of nearly horizontal calcareous sandstones, shales, and clays, about 50 feet thick, containing marine fossils. Below is a thick series of soft sands and clays containing much fossil wood and a few freshwater shells. The lower ground viewed from afar off appears flat, but is found to be an irregular succession of different levels with small steep steps between them. The whole is intersected by innumerable steep narrow gullies. A few miles away to the south lies the wide River Frio, an intermittent stream whose waters join the River Nueces, which flows into the Gulf. Fauuna.—A few years ago wild cattle and horses roamed these plains, probably obtaining 'a bare living during the spring months and retreating elsewhere in the drier seasons. Amongst the present fauna are some deer, the coyote, hares and rabbits, rattlesnakes, the ‘horned toad’, birds, ete. Until quite recently a tribe of wandering Indians held sway, and their old camping-grounds are marked by numerous stone arrow-heads and other remains. There is a wide territory hardly touched as yet by man, except at a few places where Artesian water has been won to irrigate the land. Vegetation.—The country is devoid of grass, but is more or less liberally sprinkled over with the prickly-pear cactus and stunted bushes of ‘mezquit’ and chaparal. All these plants are well protected with thorns and spines to resist any wretched animals which strive for existence on this barren land. In winter, cattle overcome with hunger and thirst will eat the prickly but juicy cactus leaves until their tongues are so bristling with long thorns that they are unable to draw them back into their mouths. Men who have kept cattle in these places go around the cactus bushes with gasoline lamps, burning off the thorns. The mezquit, besides being armed with thorns, has an exceedingly bitter taste, but the beans which grow upon this bush are the most serviceable fodder which the land provides. Notably amongst the other peculiar prickly desert plants is the large aloe, known as the ‘Spanish dagger’. At the centre of this plant reaching often to a height of 10 or 12 feet is a straight flower-stem bearing a spire of thickly clustered flowers which the animals find edible. The flower is amply defended by a chevrise of long strong leaves of sword-like shape, with sharp points (see Pl. XVI, Fig. 1). Along some of the watercourses, however, are a few live oaks and other trees. Large trees grow profusely on the alluvial soil alongside the River Frio. Dr. T. O. Bosworth—Arid Conditions in S.W. Texas. 483 Denudation and Transportation.—Despite the scantiness of rainfall this is a region of conspicuously rapid denudation; and the transporta- tion of the detritus to the sea is ever visibly in operation. The Sun's Heat.—The sun’s rays and changes of temperature, as usual in deserts, are causing cracking and crumbling on all bare surfaces, so that debris is continually falling down the sides of every scarp and gully. A curious instance was observed where the sun’s heat had had a hardening effect. Here in the freshwater series are certain white clays (comparable with fire-clays) which are very dry and porous, and which can readily absorb much water and become plastic. In places the occasional rain has washed them, leaving smooth hummocks, and the heat of the sun has then baked these almost as hard as pot, so that they ring when struck with the hammer. The Wind.—The wind is usually blowing steadily from the Gulf, and there is a constant visible drifting of material to northward -into the valleys of the River Frio and its branches. So effective is the wind that in most cases the talus is disintegrated and removed from the foot of the hills as fast as it can form, and consequently the bluffs are but littie protected, and steep scarps are the rule. Pebbles.—The fragments of sandstone, calcareous sandstone, and claystone seldom survive even as small pebbles at any distance away from the cliffs, but are quickly reduced to their component grains. Nevertheless, the desert surface generally is littered over liberally with certain small pebbles which decrease in size at a distance from the bluffs, until in the flat plains they are about the size of beans. In places they are some inches apart, in others they almost conceal the sand (Pl. XVI, Fig. 2). These pebbles in this district are a peculiar assortment, for they consist almost all of chert, agate, chalcedony, and opal. The pebbles are cut so as to have many facets and many sharp edges and corners, and are highly irregular in shape: indeed, they resemble broken flints. None were found of the typical dreikanter pattern, though all are most highly polished and almost lustrous (Pl. XVI, Fig. 3). Approaching the bluffs they are larger and have less facets, and some can be found whose undersides are fractured surfaces which have not yet been presented to the wind. ‘The source of this chalcedonic material is the marine series which caps the bluffs. In those rocks there are numerous fossils, most of which (corals, gasteropods, etc.) ‘are preserved beautifully in semi-opalescent silica, many cracks in the rocks also being occupied by this material. The wide-spread pebbles probably indicate the former extension of the series over many miles, and are evidence of the considerable denudation effected under present conditions. Frequent also among the pebbles are larger stones consisting of silicified wood derived from the freshwater series. Some of the grey calcareous sandstones which form pebbles at the foot of the cliffs are somewhat curiously affected. Outside they have a white shell-like coating up to 4in. thick (which is soluble in hydrochloric acid), and underneath this is a reddish coating of iron oxide. These materials presumably have been drawn out to the ‘ 484 Dr. T. O. Bosworth—Arid Conditions in S.W. (Ss surface of the stone by capillary action when heated by the sun after moisture has sunk into them. The Sand and Soil.—The desert sand is derived from the rocks at hand; it is rather fine and not particularly rounded. It may be a few feet deep, but more often it is only a few inches, and even in the low flat ground bare rocks are here and there exposed. Occasionally sand completely covers a layer of pebbles, but generally it seems to be the presence of pebbles which enables the sand to remain at rest; vegetation may then obtain a footing and allow the accumulation of further sand. Where vegetation retains a hold, patches of rich dark soil are readily formed which is sometimes 3 or 4 feet thick. But owing to the wind (and also to the water-flows) the distribution of sand and soil is ever undergoing rapid change. At the ranch mentioned, for instance, an attempt was being made to grow a plot of maize; at one end of the plot a man was ploughing, but at the other end the ground ploughed the day before was so completely covered by sand that no marks of the plough were visible. Again, during the rains, the bare rocks became exposed in places where two days before there had been 3 feet of soil. Work of Water.—The land surface is intersected by innumerable watercourses (Pl. XVII, Fig. 4) which lead ultimately northward and westward into the River Frio or its tributary, the San Miguel River. During the greater part of the year those rivers are dry, though a little water can usually be obtained by digging in the river- bed. At other times there is a moderate flow of water wandering about in a wide valley which is choked up with a great amount of sand and stones, often disposed in big shoals. These rivers are always overloaded, and at the time of the rains they become torrents bearing an immense load to the sea. The gullies leading inte them are narrow gorges up to, say, 30 feet deep, with steep sides, often vertical. By their complicated windings and the windings of their countless little tributaries where they converge they dissect the ground into ‘bad lands’ on a small scale (Pl. XVII, Fig. 5). Further from the river the creeks become much smaller, so that the area is mainly cut up by a network of narrow little dry gullies a few feet deep. It was the writer's good fortune to be present in April when the rains came. The creeks filled immediately, and overflowed so that sheets of water spread far and wide, flowing out over the sand and forming large ‘water spreads’, Fresh watercourses were cut from day to day, so that the system was completely changed. ‘Talus was washed away from the bluffs, pebbles were spread out or washed up into banks, new shoals of sand were formed, stunted trees were uprooted, and soil removed. At intervals between the rain-storms, which usually occurred at night, the sun shone brightly, the waters partly dried up and revealed in the creeks and on the flats fresh sand and mud surfaces all marked with water-ripples and sun-cracks, where previously had been wind-ripples or dry sand. Ripples.—These water-ripples, whether in the creeks or on the flat, when formed by advancing water present one constant pattern, generally in high relief—a kind of horseshoe pattern with all the ‘shoes’ leading forward (Pl. XVII, Fig. 6). At bends in the Grou. Maa. 1913. T. O. Bosworth photo. Arid Surface-features in South-West Texas. Piatt XVII. Or Dr. T. O. Bosworth—Arid Conditions in S.W. Texas. 485 course of the current the ‘horseshoes’ are obliquely distorted... The wetted surfaces, having the appearance of mud flats, are rapidly cracked up by the sun’s heat into hexagonal patterns with wide cracks. Drying proceeds rapidly and sometimes surface films of the hexagons may be seen curling up, each into a thin roll, and then crumbling up into ordinary fine quartz sand. Remarkably rapid was the effect of the sudden rains upon the vegetation. The stunted mezquit bushes put forth abundant light yellow-green leaves, and in a day or two the ground was ablaze with bright-coloured flowers, so that in every direction as far as the eye could see the earth appeared red or blue or yellow, or of varied hue, as the case might be. (These small plants display much flower and very little leaf.) A multitude of small Gasteropods feed upon this vegetation. Gypsum.—Gypsum is being formed almost everywhere. In the floors of the gullies are occasional growths, several feet across, composed of spherulitic structures, the spherules being upwards of ‘several inches in diameter and built of radiating fibres. On all talus slopes where there is argillaceous material, thin sheets and slabs of gypsum are ever forming. They appear to grow a few inches beneath the surface, and also in cracks. The slabs are formed of fibres normal to the plane, and are usually only a fraction of an inch in thickness, though some are thicker. There are also single larger crystals of selenite of the usual form. It appears that gypsum grows very readily in argillaceous matter which is mae exposed to the sun’s heat and is occasionally moistened. Desert Deposits.—Although the whole region is overspread with sand, yet nowhere were any thick deposits observed to be forming. Indeed, the resultant effect of wind and water in this area is gradual denudation, with intermittent sudden transferences of material to the River Frio, and thence by sudden impulses to the sea. The deposit due to the denudation in this desert is a delta cone in the Gulf of Mexico, and it is only there that the blown sand and the multitude of hard wind-cut stones come to a lasting rest. EXPLANATION OF PLATES XVI AND XVII. FIGs. PLATE XVI. 1. Characteristic vegetation of the arid regions of Texas, consisting of: ‘prickly-pear cactus’ (Opuntia vulgaris), ‘Spanish dagger,’ the large aloe (Yucca aloifolia), bushes ‘of ‘mezquit’ (Prosopis glandulosa), and ‘chaparal’ (thick bramble-bushes entangled with thorny shrubs in clumps). 2. Sand and stone-covered plains (typical view). 3. Wind-cut pebbles on the desert (mainly chalcedony). PLATE XVII. 4, from the 4reh@ocyathus limestones of Sardinia, As regards the former genus, it was shown by Dr. Hinde? to be congeneric with Girvanella (Nich. & Eth.). It is of interest, however, to note that Bornemann describes this form as a calcareous alga, and compares it with existing subaerial Alge growing on the surface of limestone rocks in Switzer- land. The latter genus is stated by Seward to be possibly ‘‘a Cambrian alga, but the figures and descriptions do not afford by any means convincing evidence ” (Fossil Plants, vol. i, p. 178). More recently, in 1904, Dr. T. Lorenz ? has desorbed remains of Siphonee from the Cambrian rocks of Tschang-duang in Northern China, for which he erects two new genera, Ascosoma and Mitscher- lichia, placing them in a new family, the Ascosomacee. These Algeze build important beds of limestone, the individuals often attaining a length of 4cm. and a thickness of 1-5em. In 1907 Bailey Willis +* reported Girvanella associated with oolites in the lowest Cambrian Man-t’o Beds in China. It is probable, therefore, that as our knowledge of these rocks is extended, Calcareous Alge will be found to play an important part in the Cambrian limestones of the Asiatic Continent and Australia.° ORDOVICIAN. In the Ordovician rocks the remains of Calcareous Algw become much more abundant; they are very widely distributed and for the first time they become important rock-builders. In Britain the chief genera met with are Girvanella and Solenopora. These two organisms occur abundantly in the Scottish Ordovician rocks of the Girvan area, where they appear to have contributed largely to the limestones of the Barr Series in Llandeilo—Caradoc times. As already mentioned, Gurvanella problematica was originally described by the late Professor Nicholson and Mr. R. Etheridge, jun., from the Craighead Limestone at Tramitchell, where it occurs in great numbers. The officers of the Geological Survey also report it from the Stinchar Limestone of Benan Hill. It occurs in the form of small rounded or irregular nodules, varying in diameter from less than a millimetre to more than a centimetre, many of the nodules showing marked concentric structure. In Benan Burn, where these beds are admirably exposed, the Girvanella nodules appear con- spicuously on the weathered surfaces, being so abundant as to constitute thick layers of. limestone. 1 Nova Acta Cees. Leop. Car., 1887 and 1891. 2 Hinde, GEOL. MAG., Dec. III, Vol. IV, p. 226, 1887. - > Centralb. f. Min., 1904, p. 193. 4 Research in China, 1907. > Chapman, Proc. Roy. Soc. Vict., 1911, p. 308. ® The Silurian Rocks of Britain, yol. i, Scotland (Mem. Geol. Sury. U.K.), pp. 487, 494, 496, 500. Prof. Garwood—Calcareous Alge. 493 Solenopora compacta, var. Peachw, which likewise forms important masses of limestone, is found, like Gurvanella problematica, most abundantly in the Girvan area, but at a somewhat lower horizon, namely, in the ‘nodular limestone’ and shales forming the lower subdivision of the Stinchar Limestone. The horizon of the Stinchar Limestone is correlated by Professor Lapworth with the Craighead Limestone, and considered to represent the summit of the Llandeilo or the base of the Caradoc rocks of the Shropshire district. It is of interest to note that Solenopora is here accompanied at times by well- marked oolitic structure, and that the same is true of the pebbles with which it is associated in the conglomerate at Habbie’s Howe. Although the marked development of Solenopora found in the Stinchar Limestone ceases with the advent of the Benan conglomerate, the genus appears to have survived in the Girvan district into Upper Caradoc times, for Dr. Brown describes a new species (S. litho- thamnioides) from Nicholson’s collection from the Ordovician -(? Silurian) beds at Shalloch Mill, where it is said to occur in conical masses the size of a walnut. Specimens of Solenopora from Shalloch Mill in Mrs. Gray’s collection were obtained from Professor Lapworth’s Whitehouse Group. South of the Scottish border there is, so far as I am aware, only one locality from which Calcareous Algze have been recorded in rocks of Ordovician age, namely, Hoar Edge in Shropshire. Here large. examples of Solenopora compacta were obtained in 1888 by Professor Lapworth from the calcareous layers near the base of the Hoar Edge Sandstone. ‘The specimens were handed to Professor Nicholson, who records the circumstance in his description of S. compacta in 1888." The form occurs here at the base of the Caradoc beds, and therefore at an horizon which corresponds closely to that of the Craighead Limestone of Girvan. Professor Lapworth also informs me that he has obtained specimens of Solenopora from a limestone in south-west Radnorshire. As the upper portion of the limestone in which it is found contains a Silurian fauna, it is possible that it is here present at a higher horizon, though the constancy with which it occurs elsewhere, in beds of Llandeilo— Caradoc age, would seem to point to the possibility that beds of Upper Ordovician age are also present in this area. In any case its occurrence here is of considerable interest. Foreign Ordovician. Outside of Britain the most important development of Calcareous Alge in rocks of Ordovician age is found in the Baltic Provinces. Solenopora occurs here in the Upper Caradoc or Borckholm Beds of Schmidt’s classification—where it makes up thick beds of lime- stone—and it is noteworthy that this horizon is practically identical with that at which S. lithothammioides (Brown) occurs at Shalloch Mill. Other specimens of Solenopora were collected by Professor Nicholson in Saak, south of Reval, from the underlying Jewe Beds, an horizon which must correspond very closely to that of the Craighead Limestone 1 GEOL. MAG., Dec. III, Vol. V; p. 22, 1888. 494 Prof. Garwood—Caleareous Alge. of Girvan. Speaking of these beds Nicholson & Etheridge remark : ‘At this locality S. compacta not only occurs as detached specimens of all sizes, but it also makes up almost entire beds of limestone ; indeed, some of the bands of limestone at Saak look like amygdaloidal lavas, while others have a cellular appearance from the dissolution out of them of the little pea-like skeletons of this fossil.”’ In Professor Nicholson’s collection from these beds Dr. Brown? afterwards distinguished two new species, namely, S. nigra and S. dendriformis. Thus, in the Ordovician rocks of Esthonia, Soleno- pora plays quite as important a part (as a rock-forming organism) as it does in the Girvan district in Ayrshire. In Norway, again, in the Mjésen district to the north of Christiania, Solenopora occurs plentifully in Stage 5 of Kizer’s* Ordovician series. Here it is very abundant and often builds entire beds, while, further east, at Furnberg, Kiser again records the occurrence of abundant nodules of Solenopora compacta, var. Peachit. In addition to Solenopora, however, examples of another important group of Calcareous Alge, the Siphones, occur in great abundance in the Ordovician rocks of the Baltic region, where they play a part in the formation of calcareous rocks scarcely less important than that played by Gyroporella and Diplopora in the rocks of the Alpine Trias. he chief forms belong to the family of the Dasycladacee, which is represented in our present seas by the recent genus Meomeris ; they include the genera Palgoporella, Dasyporella, Rhabdoporella, Vermiporella, Cyclocrinus, and Apidium. These algal limestones represent the horizons from the Jewe Limestone to the Borckholm Beds inclusive. They were originally investigated by Dr. E. Stolley,* who described their occurrence in the numerous boulders which are strewn over the North German plain in Schleswig- Holstein, Pomerania, Mecklenburg, and Mark - Brandenberg. The facts appear to show that during the deposition of the Jewe and the overlying Wesenberg and Lyckholm Limestones an algal facies obtained which extended from Oeland to Estland, and as far north as the Gulf of Bothnia. But eyen this area does not represent the full extent of the algal limestone facies in the North of Europe in Upper Ordovician times. In Norway, Kizr® has shown by his detailed work in the Upper Ordovician rocks (Stage 5) of the Christiania district, the important part played by the Dasycladacez in this area. Here the Gastropod limestone in places forms a ‘ phytozoan limestone’, made up of Rhabdoporella, Vermiporella, and Apidium, associated with a considerable development of oolite. Again, at Kuven and Valle, in the Bergen district, Reusch *° and 1 Grou. MaG., Dec. III, Vol. II, p. 534, 1885. 2 Grou. MaG., Dec. IV, Vol. I, p. 145 et seqq., 1894. 3 ‘*Paunistische Uebersicht d. Et. 5’’?: Vid. Selsk. Skr., 1897, No. 3. 4 Schr. d. naturw. ver. f. Schleswig-Holstein, Bd. xi, 1897, and references there given. 5 Etage 5 i. Asker. Norges Geol. undersogeles Aarbog, 1902, No. 1. 8 Silurfossiler og pressede Konglomerate, 1882. ‘‘ Bémmelgen og Karmgen”? : Med. omgiveleser, 1888. Prof. Garwood—Calcareous Alge. 495 Kolderup! have described knolls of crystalline limestone containing ‘abundant remains of Rhabdoporella (formerly described as Syringo- phyllum) associated with a Gastropod and coral fauna. We have, therefore, in Upper Ordovician times, in the North of Europe, one of the most remarkable developments of algal limestones met with throughout the geological succession. In North America Calcareous Algze are represented in Ordovician times by Solenopora compacta, which occurs in the Trenton and Black River Limestone groups, whence it was originally described by Billings under the name Stromatopora compacta. It therefore occurs in America at about the same horizon as in Saak and Britain. We may also note the occurrence of Girvanella in the underlying Chazy Limestone. This occurrence was originally described by the late Professor H. G. Seeley ? under the name of Strephochetus ocellatus, but is now generally admitted to be a species of Girvanella.® Other forms referred to this genus have also been reported by Schuchert from rocks of undoubted Ordovician age on the east coast of the Behring Straits.* SILURIAN. In Britain the only horizon of Silurian age at which Calcareous Algee play an important part is the Wenlock Limestone. Some years ago Mr. Wethered described the occurrence of Girvanella tubes in the beds of this age, especially at May Hull, Purley, near Malvern, and near Ledbury.? Foreign Silurian. Outside of Britain, however, we find at this period a marked algal development, and this again occurs in the Baltic area, where, especially in the island of Gotland, algal growths contribute largely to several of the limestones and marls. It is an interesting fact that very shortly after the disappearance of the various members of the Dasycladaceze which were so much in evidence in Ordovician times, we should have the remarkable development of another group of the Siphoneee, which, quickly reaching a maximum, built up in their turn abundant calcareous deposits. Nodules from these limestones have long been known from Gotland under the name of ‘ Girvanella Rock’, and have been recorded by Stolley® in boulders scattered over the North German plain. In 1908, however, Professor Rothpletz showed, in his interesting work on these Gotland deposits,’ that the forms hitherto alluded to under the term ‘ Gurvanella’ were in reality referable to two different genera. One of these he showed to be a new species of Solenopora, to which he gave the name S. gotlandica (distinguished from S. compacta by the comparatively small dimension of the tubes, | Ht orienterende niveau Bergenskiffe, Rhabdoporellenkalk von Kuven und Valle, Bergens Museums, Aarbog, 1897. * Am. Journ. Sci., vol. xxx, p. 355, 1885. * GEOL. MaG., Dee. III, Vol. IV, p. 226, 1887. * See Haug, vol. ii, pt. i, p. 643. _ > Q.J.G.S., vol. xlix, p. 236, 1893. 5 Schr. d. naturw. ver. f. Schleswig-Holstein, Bd. xi, 1897, and references there given. 7 Kungl. Svenska Vet. Akad. Handl., Bd. xliii, No. v, 1908. 496 Prof. Garwood—Caleareous Alge. which are only about one-quarter of the diameter of the latter species); the other he referred to his genus Spherocodiuwm, which he had created in 1890 for certain forms from the Alpine Trias.' The survival here of Svlenopora into beds of undoubted Silurian age is an interesting fact, and would lead us to expect that it may also some day be met with in rocks of a corresponding age in Britain. Of the different forms of Algz which occur in these Gotlandian deposits, perhaps the most interesting is Spherocodium, which, as shown by Dr. Munthe,? occurs at several horizons in the succession. It first makes its appearance in the marl immediately overlying the Dayia Flags — approximately of Lower Ludlow age — where it occurs in considerable masses. In external appearance these resemble very closely nodules of Ortonella from the Lower Carboniferous rocks of the North-West of England; some of the nodules appear to have reached a diameter of 4cm. The marl is overlain by sandstone and oolite, which are succeeded by an argillaceous limestone rich in nodules of Spherocodium gotlandicum and well exposed at Grdtlingbo, where it is closely associated with oolite. Among the fossils of this limestone Spherocodium itself plays the most important role. In the overlying ‘Iliona Limestone’ Spherocodium is decidedly rare, and its place is taken by Spongiostroma. As will be pointed out later, there appears to be no good reason why Spongiostroma may not be indirectly due to the presence of algal growths; but whatever may be the final position assigned to it, there can be no doubt as to . its importance as a rock-building form in the Iliona Limestone of Gotland. We may conclude, therefore, that the development of the Spherocodium beds of Gotland probably occupied originally nearly as wide an extension in the Baltic area as did the Rhabdoporella limestones during the Ordovician Period. With regard to other occurrences of Calcareous Alge in Silurian rocks, it will be sufficient to note that of Girvanella in the Silurian limestones of Queensland, recorded by Mr. G. W. Card in 1900,° and more recently by Mr. Chapman from Victoria.‘ Quite recently Mr. R. Etheridge, jun., of Sydney,® has described “‘ an organism allied to Mtcheldeanta from the Upper Silurian rocks of New South Wales’; the figures given, however, and the description are not convincing that his identification can be accepted. The size of the tubes, which are from five to six times as large as those of IL gregaria, would alone appear to remove this organism from Mr. Wethered’s genus and also possibly from the Calcareous Alge. DeEVonIAN. So far as I am aware, there is only one recorded occurrence of Caleareous Algse from the Devonian rocks of Britain—namely, in the Hope’s Nose Limestone of Devonshire, from which Mr. Wethered has described aggregations of tubules resembling Girvanella, but in a very poor state of preservation. 1 Bot. Cent., vol. lii, p. 9, 1890. 2 Geol. Foren. Forh. Stock., Bd. xxxii, Hft. v, p. 1397, 1910. 5 Bull. Geol. Surv. Queensland, 1900, No. 12, pp. 25-32, pl. iii. + Rep. Austr. Assoc. Adv. Sci., 1907-8, pp. 377-86, pls. i-iii, 1908. 5 Rec. Geol. Surv. N.S. Wales, vol. viii, pt. iv, p. 308, pl. xlvii, 1909. Prof. Garwood—Calcareous Alge. 497 Foreign Devonian. On the Continent the reported occurrences are, so far, equally poor. At the same time, the cursory examination which I was able to make of the thin sections of the Devonian limestones exhibited in the Brussels Museum leads me to expect that a careful investigation of the Belgian Devonian limestones will yield other examples besides Spongiostroma. CARBONIFEROUS. We now reach the period in Paleozoic times when Calcareous Alge attained their maximum development in England, a development rivalling that which obtained in the Ordovician rocks of Scotland and the Gotlandian of the Baltic area. The genera represented include Girvanella, Solenopora, and Mitcheldeania, while in addition to these there occur several lime-secreting organisms which, though still undescribed, will, I think, ultimately come to be included among the Calcareous Alge. The most interesting of these organisms I have recently figured from the Lower Carboniferous rocks of Westmorland, where it forms a definite zonal horizon or ‘ band’.! For this form, on account of its stratigraphical importance and for facility of reference, I propose the generic name of Ortonella.? Again, at the same horizon in the North-West Province I have frequently noticed concretionary deposits of limestone which occur as finely laminated masses, the lamine often lying parallel to the general direction of the bedding planes, which on microscopic examination show no definite or regular structure, but have every appearance of being of organic origin. Many of these puzzling forms resemble very closely the somewhat obscure structures found in the Visean limestones of the Namur basin in Belgium, of which beautiful thin sections are displayed in the Natural History Museum at Brussels,? and which Giirich has described and figured under various names—Spongiostroma, Malacostroma, etc., and which he has included under a new family, the Spongiostromide,* and a new order, the Spongiostromacez. I must confess that neither in the original sections nor in the beautiful illustrations that accompany his work can I see any grounds for referring these structures to the Protozoa. As regards the British specimens, I have long regarded them as due, directly or indirectly, to the work of Calcareous Alge, partly on account of their intimate association with well-developed examples of these organisms and also on account of the entire absence of Foraminifera and other detrital organisms wherever this structure occurs. As, however, I have little doubt that they are closely connected in their mode of origin with the Belgian specimens, we may conveniently speak of them under the general term Spongtostroma. 1 Q.J.G.S., vol. Ixviii, pl. Ixvii, fig. 2, 1912. 2 From Orton, a village between Shap and Ravenstonedale, where this organism occurs in great abundance. > One of these is also exhibited at the Jermyn Street Museum. * Mem. du Musée Roy. d’Hist. Nat. de Belgique, tom. iii, 1906. DECADE V.—VOL. X.—NO. XI. 32 498 Prof. Garwood—Calcareous Algee. Some of the best examples known to me occur associated with Ortonella in the ‘ Productus globosus band’ near the summit of the ‘ Athyris glabristria zone’ in the Shap district. They occur here: in considerable masses, often many inches in thickness, and form undulating layers parallel to the bedding, and somewhat resembling huge ripple-marks. In all cases they appear to be due to the precipitation of carbonate of lime in the neighbourhood of algal growths. I have also met with similar deposits, not only at other horizons in the Lower Carboniferous rocks of the North of England, but also in the Forest of Dean and in the rocks of the Avon Gorge; while quite recently Mr. C. H. Cunnington has sent me examples from several horizons in the Carboniferous Limestone of South Wales. Girvanella.—This organism appears to play a considerable part in the formation of calcareous deposits in the Lower Carboniferous rocks of Britain. Its presence in these rocks was first suggested by the late Professor Nicholson,1 who wrote: ‘I have found some of the Carboniferous Limestone of the North of England to contain largely an ill-preserved organism, which will, I think, prove to be referable to Girvanella.’’ This prophecy has turned out to be fully justified, not only as regards the North of England, but also in the case of the Lower Carboniferous beds of other districts. In 1890 Mr. E. Wethered described? two new forms of this genus from the Lower Carboniferous rocks of the Avon Gorge and Tort- worth, viz. G. cincrustans, with tubes having a diameter of 0°1 mm., and G. Duct, with a diameter of ‘02mm. Mr. Wethered appears to rely chiefly on the size of the tubes for the differentiation of these species, but as this distinction was made at the time when Girvanella was still considered to belong to the Rhizopods, and as the size of the tubes frequently varies in the same specimen, it is doubtful whether these species can be maintained, Mr. Wethered’s specimens were obtained from the limestone near where the Bridge Valley Road joins the river bank, apparently at the base of Dr. Vaughan’s Upper Dibunophyllum Zone. The position of this limestone is of interest, as it appears to correspond very closely with the horizon of the ‘Girvanella Nodular Bed’, which forms a well- marked band at the base of the Upper Dibunophyllum Zone throughout the whole of the North and North-West of England. Indeed, I have traced this band at intervals from the neighbourhood of Ford, near | the Scottish Border, southwards through Northumberland and the Pennine area to Penygent, and from the west coast at. Humphrey Head through Arnside and Shap to the east coast near Dunstanburgh. These organisms must, therefore, have flourished at this period over an area of at least 3,000 square miles in the North of England alone. The best exposure showing the important development of these Girvanella nodules is to be found on the dip slopes forming the eastern shore of Humphrey Head in Morecambe Bay, where the base of the Upper Dibunophyllum Zone is exposed over a considerable area. 1 Grou. MAG., Dec. III, Vol. V, 1888. 2 Q.J.G.S., vol. xlvii, p. 280, pl. xi, figs. 1, 2, 1890. (To be concluded in the December Number.) B. K. N. Wyllie & A. Scott—Plutonics of Garabal Hill. 499 1V.—Tue Pruronic Rocks oF GaraBaL Hitt. By B. K. N. WYuLIk, M.A., B.Sc., and ALEXANDER Scorn, M.A., B.Se., Carnegie Research Scholars in the University of Glasgow. HIS complex of igneous rocks lies between Ardlui, at the head of Loch Lomond, and the head of Loch Fyne. In 1892 it was the subject of a fairly exhaustive paper by Teall & Dakyns,' but in view of a number of new facts which we have discovered we venture to submit a re-examination of the problems connected with the complex. The mass is broken by a north-east fault. The country to the west of this fault is mainly porphyritic granite and tonalite; to the east there is tonalite and also more basic diorite and ultrabasic rocks. We shall concern ourselves mainly with the basic and ultrabasic groups, as they are somewhat unusual in the ‘‘ Newer Plutonic Rocks of the Highlands ”’. Urrrapasic Rocks. The ultrabasic rocks form several small isolated outcrops along a line running N.N.K. from Loch Garabal, and passing about 200 yards to the east of Lochan Beinn Damhain (Loch Ben Dayain). The largest of these covers about one-eighth of a square mile, and lies immediately north of Loch Garabal. About 200 yards east of the north end of Lochan Beinn Damhain, and near a little lochan, another exposure appears, followed to the north by two others. The total area is about 200 square yards. A mere patch is also found about 100 yards south of the small lochan, and further north still, at a place 400 yards north of the highest point of Garabal Hill, a congeries of weathered blocks probably indicates another minute outcrop. The Geological Survey map of this area claims a long narrow strip, further north than our last-mentioned exposure, as peridotite. But of this no evidence was found beyond a few scattered boulders.? The map in the paper by Teall & Dakyns includes likewise some peninsulas and islands of schist in the plutonic rocks. A careful examination of these localities proved the outcrops to be partly schist and partly diorite, the field relations of the two, however, indicating that the schist represents the residuum of the original ‘roof’, which has so far escaped total denudation. A similar schist roof has been recorded by Barrow in Glen Tilt. It is noteworthy that this chain of exposures is practically coincident with the line which separates the diorites from the later tonalite. But we have not been able to decide whether the ultrabasic masses are actually wedged in between these two or _enveloped in the diorite close to its margin. On the diorite side 1 “Plutonic Rocks of Garabal Hill and Meall Breac’’: Quart. Journ. Geol. Soc., xlviii, pp. 104-21, 1892. 2 The sketch-map of Teall & Dakyns is reproduced in Hatch’s Petrclogy (p. 303), but with the omission of all the peridotite areas we have mentioned, except the one we failed to find, while the positions of Garabal Hill and Garabal Cottage are interchanged. 3 Geology of Upper Strathspey, etc. (Mem. Geol. Surv. Scotland), 1913, p. 72. ; 500 B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. the junction is plain, but on the other side it is obscured in every instance by peat, though tonalite is exposed in mass close by and intersects both the others in dykes and strings. The predominant type among the ultrabasic rocks is a pyroxenite, with large bronzy diallage crystals which often weather out like phenocrysts. Olivine is seldom absent; it occasionally equals the pyroxene in amount; and in places we find veins of pure serpentine, representing the end product of this replacement. All intermediate stages are found between pure olivine (serpentine) rock and pure pyroxenite. In one place an olivine-bearing rock is found forming a vein 6 inches thick in a pyroxenite. 5 S / 7 7s Ty de 1S is Ms Arey ~ a & 1 4 = a S S Ho & res Schist aap : ve - ¥ 0 : T* SH i re vig) fee kav eee Ly Om iy ae ? . ve Beinn Damhain y ea a e Nadaicls ae ee aval 5 Ws © ss \w 5 o By Z o, oe . Hull He S: cH “ ff Bei Pie wg aos Schist Cap. io Z S 7( Da firain . \ 4 : IN Ny A N “3 ise @ pa on S r ra : 0 oY Ardlut We V Hornblendite Tonalule Duorile , 2 Ultrabaste Rocks (2 A Mica Schusts Fig. 1. Sketch-map of the basic and ultrabasic rocks of Garabal Hill. Scale 1:7 inches =1 mile. Note: 3’ marks the area mapped by Teall & Dakyns as peridotite, but the only evidence of peridotite that we could find was some scattered boulders. A rock of entirely different appearance occurs in large masses at locality ii (see Map, Fig. 1) and in little strings at Loch Garabal. This is composed of glossy coal-black crystals of hornblende of a granular texture, with grains varying up to } inch in diameter. At locality i1 (see Fig. 1) this rock is found always intervening B. KN. Wyllie & A, Scott—Plutonics of Garabal Hill. 501 between the diorite and the pyroxene-olivine rocks. It is some- times penetrated by the diorite in such a way that the two are hard to distinguish. In thin section this rock is found to be practically a hornblende rock. The hornblende is brown, with pleochroism from dark brown to light yellow.’ The crystals are uniform in size and packed closely together with few interstices. The cores of the crystals are very commonly of diallage, with flecks of hornblende arranged symmetrically throughout them. These pyroxene cores, again, show a sprinkling of parallel-orientated schiller rods. Even in crystals which have no colourless core these schiller patches occur, and the explanation is obvious that all the hornblende was formerly pyroxene. Grains of rhombic pyroxene (enstatite) occur, sometimes in clusters, more often separately. Generally they are seen to be an earlier formation, the hornblende being moulded round them, or enclosing them. Interstitial felspar is scanty or absent. But veins occur which are more felspathic, the felspar then amounting to about 10 per cent of the whole. Where determinable, this felspar presents the characters of andesine. Grains of apatite are also an important accessory, and a few scattered flakes of biotite can always be distinguished. This rock seems to be unique in Scotland, and as we have not been able to parallel it elsewhere, we propose to refer to it for the present as Davainite, which we therefore define as a rock consisting essentially of brown hornblende, which is paramorphic after pyroxene, the total amount of other minerals such as hypersthene and felspar being sma]l. The name hornblendite we reserve for an end-member of the diorite series, to be mentioned hereafter. The other ultrabasic rocks show, under the microscope, diallage, enstatite, olivine, brown hornblende, biotite, and black oxides, with a constant but small amount of apatite. Olivine is generally serpentinized where it is present in considerable amount. Biotite is almost always present, though never abundant. LEnstatite is generally subordinate to diallage, but usually fairly abundant. Hornblende is the same brown variety described in Davainite. Here also it seems to be new-formed from pyroxene, and all stages of the replacement are found. Some specimens from the centre of the Loch Garabal mass show no hornblende. It seems to increase in amount towards the margins. Locally, a small amount of basic plagioclase (bytownite) appears. Diallage is by far the most abundant constituent. It occurs in large crystals, giving the rock a porphyritic aspect. In one case this porphyritic structure is quite real, as the interstitial matter is eranular olivine, enstatite, and smaller diallage crystals. The rock in which this is found is a vein, intrusive into a finer-grained pyroxenite, so that the phenocryst explanation is reasonable. The diallage crystals are commonly rendered dusty or dense by parallel- orientated schiller inclusions. 1 The pleochroism of the hornblende is: X, light yellow; Y, dark brown; Z, reddish brown. 4 * 502 B. K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. Reckoning the hornblende as equivalent to pyroxene, we may state the rock-types represented, as follows:— PYROXENITE. (Diallage—-enstatite. ) [(Gabbro) + Norite.] Lherzolite and Wehrlite. Picrite and Enstatite-picrite. (Di. En. Ol.) (Di. O1.) (Di. Ol. (Di. En. Ol. Felspar.) Felspar.) Pyroxene—peridotite. (Ol. with little Di. or En.) oe rock. We have not found any rock rich enough in felspar to be called gabbro, though the felspathic veins in davainite come very close to that. A norite has been recorded at locality ili (Map, Fig. 1), but this is a hybrid rock and will be mentioned later. DavarnireE. We have now to substantiate at greater length our contention that the brown hornblende here found is altered diallage, and, consequently, that the rock we designate as davainite is the equivalent of the pyroxenites. There are two possibilities: (1) the change may have EFer/dotite Px) Davainite Diarite Fe‘) Tonatile E44 rat Fic. 2. Sketch-map showing the occurrence of Davainite at locality ii. (See Map, Fig. 1, ante, p. 500.) occurred during cooling, and may denote a transition temperature below which hornblende is stable, and above, diallage; (2) the change may be due to some kind of annealing of the diallage rocks by the later diorite magma, which, as we have noted, is in intimate contact with the davainite at locality 11.1 (See Map, Fig. 1.) 1 By annealing we mean reheating to a temperature which is lower than the melting-point of pyroxene, but which lies in the region where hornblende is the stable modification. B. KN. Wyllie & A. Scott—Plutonics of Garabal Hill. 503 The significant phenomena are these: (1) cored hornblende crystals, * showing either actual diallage, or the diallage schiller structures, in their centres; (2) partly pleochroic diallage crystals, retaining the pyroxene cleavage and extinction; (3) amphibolized veins meandering through chailllasc crystals. The last case especially ean hardly be explained on the ‘simultaneous’ view, whereas the ‘secondary’ theory explains all equally well. Moreover, it may be doubted if a mere equilibrium change during the original cooling suffices to account for the formation of a strongly coloured and strongly pleochroic amphibole from a practically colourless pyroxene. Amphiboles in general are reputed to contain hydroxyl, whereas pyroxenes do not. It is possible that the introduction of hydroxyl into a molecule gives it different optical properties: for instance, amphiboles are pleochroic; pyroxenes, as a rule, are not. But the case we have at present seems to demand still more than this; itis difficult to associate the marked brown of this hornblende with anything but a marked increase in the ferric-oxide content. We suggest, therefore, that hydroxylation and oxidation have been effected by heated vapours, and general reheating, from the subsequent diorite magma. We offer such chemical evidence as we possess in support of this idea. A specimen of davainite was analysed, but as it was more felspathic than the typical rock we have recalculated the analysis to give the proportions of the femic constituents only :— I Ta II Il. IV Vv SiQg . .| 43-53 37-00 38-6 44-94 31-84 41-01 ALO apicgh vs 1-90 2-80 — — — -66 AloO3. . 7-24 — 3-7 4-84 1:37 5-00 ~Cr,03.. — ea — -76 — 14 Fe,03. ./| 11-10 16:40 7-6 4-64 15-63 5-52 FeO .. 8-70 12-80 7:8 6-75 14-25 8-66 CaO . .| 10-19 14-00 7:7 14-70 -91 4-43 MgO . .|} 11-51 17-00 27-7 23-16 33-10 29-92 KOs neni 1-39 — 2 — —_ +25 NajgO. . 2-88 — — — — -98 HoO+ . 1:34 — 4-95 H.O- . -43 — 6-4 1-48 2-49 -43 COp . .| nt. fd. — ; -76 ROR a ee trace — — — — -10 100-21 | 100-00 99-8 | 101-23 99-59 | 100-58 I. Davainite. Ta. a recalculated. II. Wehrlite (somewhat serpentinized), L. Garabal, anal. J. H. Player.’ IV. Dane Koswinsky Kamen, North Ural. V. Peridotite, Dunan Liath, Ross-shire, anal. W. Pollard. 1 Teall & Dakyns, loc. cit., p. 115. 2 Geology of Ben Wyvis, etc. (Mem. Geol. Sury. Scotland), 1912, p. 127. 504 BLK. N. Wyllie & A. Scott—Plutonics of Garabal Hill. We note (1) that the lime content of davainite is on a par with that of the wehrlite analyses, while the comparatively low magnesia percentage is consistent with the absence of olivine. (2) The amounts of FeO, Ti Og, Fe, Og in davainite would correspond with 20 per cent , of magnetite and ilmenite in the rock, if all were so present. But 3 or 4 per cent is all that can be allotted to these minerals. Hence it appears that the hornblende of the rock must contain a large proportion of FeO and Fe,O, and probably TiOQ,. (8) Fe, 0, is decidedly in excess of Fe O in davainite, which is the reverse of their normal relation in diallage-bearing rocks. We conclude that our assumption of oxidation is supported by this analysis. We have no evidence of any considerable action on the ultrabasic rocks by the diorite magma other than this metamorphism of pyroxene: there has been no wholesale absorption, since quartz- bearing diorites are the rule close up to the contact; though the absence of olivine from the border-zone of the ultrabasic mass—at least, in all the sections of davainites we have cut—makes it possible that a slight amount of siliceous material has penetrated there. ‘Vhis is supported by the presence in davainite of a considerable amount of rhombic pyroxene; the clustered grains mentioned above will in that case represent original olivine. It is all the more significant that some of the rhombic pyroxene seems to be new-formed and of a different composition from that of the unchanged peridotites. It was mentioned that among the rock-types a norite was found. This occurrence will now be described, as it is pertinent to the foregoing discussion. ‘The rock in question forms thin irregular veins in the peridotite at locality ii (see Map, Fig. 1). In thin sections these are seen to be composed of felspar and pyroxene, with granular aplitic texture. Felspar forms about 80 per cent of the bulk except where the femic minerals are clotted together—and that always happens close to the surrounding peridotite. It consists of orthoclase, with a basic plagioclase (andesine or labradorite), the latter being far in excess of the former. In the whiter parts a few grains of quartz can be detected. Of the femic minerals, the most striking is a richly pleochroic hypersthene, which builds large idiomorphie crystals, and is much in excess of the others, which are colourless or faintly greenish enstatite and diallage. Now the surrounding rock is a peridotite, containing diallage and colourless non-pleochroic enstatite, with scattered flakes of mica. Diallage and enstatite in the two rocks are identical, and the vein rock presents in the same way a few stray pieces of biotite. The co-existence in the same melt of two different members of the iron- magnesium metasilicate minerals, which form a continuous series of solid solutions, is obviously impossible. Hence one of them must be xenocrystic, and that one can only be enstatite. The explanation is therefore plain: the vein rock is a hybrid, formed by partial solution of peridotite matter in a quartz-aplite, such as are abundantly associated with the later tonalite magma. LEnstatite has remained unattacked. The solution of olivine has produced hypersthene, with elimination of nearly all the free silica of the solvent. Diallage has B. K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. 505 been only partly decomposed, but that partial decomposition has set free a certain amount of lime, with the result that plagioclase is more basic than is commonly the case in aplites. It should be mentioned also that the diallage shows the usual alteration to brown hornblende, though that is not nearly so advanced as in the davainite. When the case is considered from the purely chemical point of view, this ‘selective solution’ is easily understood. Olivine, being an orthosilicate, is unsaturated with respect to silica and hence would be easily attacked, the resultant product being the metasilicate, hypersthene (Mg Fe $i, 0,). Enstatite, a metasilicate, is saturated with silica and hence remains undissolved, unless the temperature is very high. Diallage, while chiefly composed of metasilicate molecules, also contains compounds of the type R” Al, Si Og, and these can take up more silica to form types such as R” Al, Si,0,. Thus the formation of anorthite, and consequent basification of the plagioclase, may be expressed by the equation Ca Al, Si O, + 810, —> Ca Al, Sig Og. TonaLite AND DIoRITE. Garabal Hill itself is composed of a series much more acid than those described above. There are clearly two separate rock masses, the earlier one comprising diorites with a considerable variety of structure and mineralogical composition, while the later one is a more or less uniform tonalite. The latter is obviously intrusive into the former, as it penetrates both the diorites and davainites in numerous veins of varying thickness, and generally with sharp junctions and no commingling on the margins. The tonalite consists mainly of deep-brown strongly pleochroic biotite and zoned oligoclase in a matrix of quartz, orthoclase, and plagioclase. The quartz and felspar contain numerous inclusions of apatite, zircon, and sphene, while in the ground-mass sporadic crystals of sphene and muscovite are found. In the region of Garabal Hill the rock is even-grained and not particularly coarse, although in one or two places mica ‘clots’ are found, consisting of aggregates of biotite, with strong absorption, and subordinate interstitial quartz and felspar. These probably represent foreign material which has been absorbed and completely recrystallized. Near Meall Breac, to the west of the fault and in the area mapped by the Geological Survey as tonalite, a much coarser rock is found. It differs from the tonalite described above, not only in texture but also by the presence of green hornblende, equalling in amount the biotite, and of fairly large crystals of sphene. It closely resembles some of the more acid diorites and should probably be classed with them. The diorites differ considerably in the different localities, and grade from fairly acid, quartz-bearing rocks to pyroxene diorites and hornblendites. The chief constituent minerals are quartz, orthoclase, plagioclase, mica, hornblende, pyroxene and sphene. The plagioclase in the more basic varieties is labradorite-andesine, but oligoclase is found in the ‘acid’ rocks. The quartz and felspar are rich in inclusions of apatite, zircon, and occasionally rutile. The mica is generally biotite with strong pleochroism and absorption, and often 506 B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. altering to chlorite. Sphene occurs in pleochroic yellow crystals as well as in the common granular form. The pyroxene is a pale-gr een diopside with an extinction of 30°-40° and showing generally schiller inclusions. Occasionally aluminous pyroxenes are also found. The amphibole is the common green hornblende with low extinction and strong pleochroism from light to dark green. It occurs partly as the margins of pyroxene crystals, or as a paramorphic replacement of these, and partly as original crystals. It undergoes alteration in two ways, sometimes to aggregates of pale-coloured actinolite, sometimes to a brown hornblende with a complicated pseudo-schiller structure, which will be described later. One of the more acid types occurs on the south-east slopes of Garabal Hill, and consists of quartz, felspar, and green hornblende, with subordinate biotite, and chlorite. The felspathic minerals greatly preponderate, though the amount of quartz is comparatively small. Sphene is common, and is usually altering to ilmenite or leucoxene. A much coarser rock with abundant sphene and apatite, and no quartz or biotite, is found to the east of Loch Garabal. The felspar is nearly all saussuritized, while the original hornblende is replaced by fibrous aggregates of actinolite or tremolite. Occasionally traces of original pyroxene cores surrounded by paramorphie horn- blende are found. In places this passes to a quartz-bearing rock with a fair amount of biotite, while the hornblende assumes a more prismatic habit than usual. This rock is probably some kind of ‘schlieren’, as it is more acid than the surrounding rocks, and at other localities, which will be described later, obvious schlieren are found, containing amphibole of similar habit. The diorite which forms the eastern margin of the main davainite area somewhat resembles the Loch Garabal rock. It is finer in grain than the latter, but the felspar is partly replaced by saussurite and the hornblende by actinolite. Quartz is absent, while the presence of original pyroxene is indicated by hornblende ‘aggregates containing traces of original diallage or diopside. A few small flakes of biotite, which is probably secondary, are also present. On the ridge north of Garabal Hill a rock occurs which seems to be the most basic of the diorites; it probably approaches a gabbro in chemical composition. It is a medium to coarse-grained aggregate of plagioclase, hornblende, and pyroxene, with subordinate orthoclase and biotite and no quartz. The felspar is a comparatively unaltered labradorite exhibiting good twinning, while the hornblende is a green mineral more or less completely altered to brown, and the pyroxene is the pale-green diopside common to the diorites. The felspar occurs in coarsely eranular aggregates filling up the interstices between the ferro- magnesian minerals. Mineralogically the rock might also be described as a hornblende-gabbro. In the neighbourhood of loc. iii (see Map, Fig. 1) numerous veins and clots occur, rich in epidote. Sections were made of specimens from one such vein which showed some considerable variety. The centre of the vein consisted ef epidote, vesuvianite, and spinel, with occasional crystals of hornblende. The epidote occurs as an even- grained mass of subhedral crystals with pleochroism from yellow to B. K.N. Wyllie & A. Scott—Plutonies of Garabal Hill. 507 pale-green and somewhat larger in size than the crystals found in similar veins in Cornwall. Minute crystals of blue magnesia-bearing spinel are found bordering the epidote. In the centre rock the vesuvianite occurs interstitially, and is obviously the last mineral to erystallize, but towards the margins aggregates of large hornblende and idocrase crystals occur, both being subhedral. The vesuvianite erystals are brownish to colourless, with occasional lamellar cleavage and the characteristic low double refraction. The amphibole resembles the green hornblende of the diorite, but is obviously changed in places to a mineral resembling glaucophane, while else- where epidote and vesuyianite have developed at its expense, the erystals being very much corroded round the margin. The vein is bordered by a narrow band of typical hornblende schist, consisting of blue-green amphibole, quartz, orthoclase, and albite, with occasional patches of the original dioritic hornblende in a state of partial alteration. Epidosites have been described by the Geological Survey from both sedimentary and igneous schists and gneisses in the Lizard district! and also from the Kilmartin district, where they occur in epidiorites.2 Those occurring in the sedimentary rocks are generally quartzose, and are probably produced by the shearing of rocks which were weathered before being metamorphosed. ‘The ‘ igneous’ epidosites, however, are assumed to be due to chemical segregation during movement, and it is this explanation which seems to be most applicable in the case of the Garabal Hill rock. The epidote rocks of the latter area differ from those of Cornwall by the almost complete absence of minerals other than the lime-bearing ones—the amount of spinel is exceedingly small. They seem to have formed along shearing planes in the diorite, where the country rock has undergone strain of such intensity that it has been rendered com- pletely fluid. The neighbouring rock is a hornblende-pyroxene- diorite with a basic plagioclase as the only felspathic mineral. The shearing has resulted in chemical interaction between the felspar and the ferromagnesian minerals, with the formation of epidote. Several cases of the production of epidote as a contact mineral between felspar and hornblende‘ have been recorded, and it seems probable that the reaction between these two minerals in a fluid state in presence of water is comparatively simple. The crystals on the margins would be easily attacked, the large hornblendes which are partly corroded being those which have been incompletely dissolved. This solution effect would also explain the partial age cregation of the vesuvianite at the margins, as the latter is richer in lime and poorer in alumina than epidote, while hornblende is 1 Flett in Geology of Lizard and Meneage (Mem. Geol. Surv. England), 1912, Pp. 36, 46. 2 Flett in Geology of Seaboard, Mid-Argyll (Mem. Geol. Sury. Scotland), 1909, pp. 47-50. 3 At several other places on Garabal Hill evidence of faulting is found; thus at loc. iv (see Map, Fig. 1) a line of brecciated diorite with numerous quartz-veins can be traced for about 20 yards. 4 G. H. Williams, Bull. U.S. Geol. Sury., 1886, No. 28, p. 31; F. D. Chester, Bull., 1890, No. 58, p. 35. 508 Dr. Shand—Saturated & Unsaturated Igneous Rocks. likewise richer in lime and poorer in alumina than felspar. The vesuvianite aggregates, therefore, are the product of the solution of hornblende crystals in a fluid so viscous that but little diffusion could take place. The interstitial vesuvianite arises through a com- bination of two causes: (1) The ratio of lime to alumina in the diorite is, as stated above, higher than that required for the formation of epidote. (2) The diorites contain appreciable amounts of magnesia and alkalis. Part of the former crystallizes as spinel, but the remainder, together with the alkalis, would enter the vesuvianite molecule, which can have up to 6 per cent magnesia and 2 per cent alkalis, while epidote rarely has more than a trace of either. (To be concluded in our next Number.) V.—On Saruratep and UnsatvuratEpD Igneous Rocks. By Professor 8S. J. SHAND, D.Sc., Ph.D., F.G.S., Victoria College, Stellenbosch, South Africa. F the various minerals which enter into the composition of igneous rocks, about one-half are capable of forming in presence of free silica, as is shown by their association in rocks with quartz and tridymite. These may, for the present purpose, be termed saturated minerals ; they include some of the most highly silicated compounds of their respective metallic elements. The remaining rock minerals do not appear in association with free silica, and may be presumed to be incapable of stable existence in its presence; they are mostly the less highly silicated compounds of the same metallic elements which enter into the former group. These may, for the present purpose, be termed unsaturated minerals. ‘The unsaturated character of any mineral in the latter group is not affected by the temperature and pressure at which crystallization takes place; this is shown by the fact that quartz and the minerals referred to are mutually exclusive both in plutonic and in effusive rocks. In the case of sodium, potassium, calcium, and magnesium the formation of saturated or unsaturated minerals appears to depend only on the amount of silica available in the magma. Aluminium, ferrosum, and ferricum, elements of feebly basic character, have their combinations largely determined for them by the more strongly basic elements, with which they tend to form either complex molecules or mix-crystals. In the following table the saturated and unsaturated compounds of each element are placed us far as possible in apposition :— Saturated. Unsaturated. Orthoclase. Leucite. Albite. Nephelite. Sodalite. Nosean. Analcite. Cancrinite. Anorthite. Hauyne. Melanite. Melilite. Pyroxenes. Olivine. Annphibotes | Pyrope. Micas. Picotite. Dr. Shand—Saturated & Unsaturated I gneous Rocks. 509 Saturated. Unsaturated. Tourmaline. Spessartite. Topaz. Corundum. Titanite. Perovskite. Magnetite. ilmenite. Apatite. Zircon. I anticipate that objection may be raised to one or two of the minerals classed here as unsaturated. ‘The first of these is olivine. A few dolerites and basalts have been described as containing both quartz and olivine, but I think the experience of most petrographers will show that this association is quite unusual. I have never come across an instance of it in the field, and I think it highly probable that the explanation of such an unusual association is that the quartz is not of magmatic origin. The only example of a quartz-olivine rock in my collection is the ‘melaphyre’ of Albersweiler in the Rhenish Palatinate, which contains small ‘phenocrysts’ of quartz. An examination of this rock decidedly suggests that the supposed phenocrysts are really xenocrysts. They are just as often aggregates as single grains, and they are always anhedral, with rounded, fretted outlines. But to be sure of this one would require to study the rock in the field. Harker’ and Mennell? have both described occurrences of quartz xenocrysts within basalts and dolerites. In the cases described by Harker, basalt sills which were invaded by granophyre have been acidified and impregnated with quartz xenocrysts by the latter. In the dolerite intrusions in the Matopo granite, which Mennell describes, the quartz xenocrysts and the interstitial micropegmatite of the dolerites are due to absorption of granite. In at least one of these intrusions olivine is present. As the latter is a mineral of very early crystallization it is evident that the absorption or incorporation of quartz may occur too late to prevent the partial separation of magnesium in the form of olivine, and hence the two minerals may exist side by side. According to this view such quartz-bearing dolerites would be hybrid rocks, not true magmatic products. For further evidence bearing upon this point I must await the judgment of those who have the opportunity of studying such exceptional rocks in the field. As regards corundum, I know of no instance where it occurs in association with quartz in igneous rocks; its common hosts are nephelite-syenites, anorthosites, and peridotites. Any excess of alumina over bases in the quartz-bearing rocks always seems to appear as muscovite or topaz, not as corundum. It may seem strange that garnets should fall into two contrasted groups, the spessartites (and probably the almandites as well) being regarded as saturated while others (melanite, pyrope) are unsaturated ; yet this is simply an expression of observed facts of distribution. In my Own experience of melanite rocks in Sutherlandshire,? where 1 Tertiary Igneous Rocks of Skye (Mem. Geol. Sury., 1904). # “Basic Dykes and Rock Genesis ’’: Gmou. MAG., 1911. 3 Trans. Edinb. Geol. Soc., 1910. 510 Dr. Shand—Saturated & Unsaturated Igneous Rocks. quartz syenites pass insensibly into melanite syenites, the first trace of melanite does not appear until the last trace of quartz has been lost, although there is no immediate change in total lime content. Anorthite, too, appears at first sight to occupy an anomalous position ; it is an orthosilicate occurring in a group which is mainly composed of polysilicates and metasilicates. But calcium metasilicate (wollastonite) is incapable of independent existence under magmatic conditions, hence the orthosilicate is the stable form even in quartz- bearing rocks. ‘True quartz-anorthite rocks are probably rare, but the anorthite molecule must have been present as such in the parent magma of every quartz-plagioclase rock. Magnetite and ilmenite are of course completely unsaturated as regards silica, from the chemical point of view, but as both are capable of stable existence in the presence of free silica under magmatic conditions, they rank here as saturated minerals. (Should it be felt that this new use of a common term is liable to be misunder- stood, the reader may at his pleasure read sated and unsated in place of ‘saturated’ and ‘ unsaturated ’.) A rock which contains only saturated minerals may be termed a saturated rock; one which contains only unsaturated minerals may be termed an unsaturated rock. It will also be desirable to distinguish partsaturated rocks (e.g. phonolites, olivine-dolerites) from wholly unsaturated ones; as a general term to cover both partsaturation and unsaturation we may employ wndersaturation. Any rock which contains free quartz or tridymite of magmatic origin will be termed oversaturated. These distinctions are by no means trivial; they have a very definite chemical significance which has a bearing upon the reaction of the magma towards invaded rock masses, and hence upon magmatic differentiation. They are also capable of useful application in the classification of igneous rocks. 1. An undersaturated magma (i.e. one which on solidifying would give rise to a partsaturated or unsaturated rock) is capable of entering into chemical combination with the silica of invaded rock masses. The reactions thereby induced would be exothermic, and would tend to raise the temperature of the magma. The amount of heat to be gained in this way does not seem to be susceptible of direct measure- ment at the present time: the difficulties to be overcome would be very great, but as silicic acid is known to be an exceedingly powerful acid at high temperatures, it is probable that the heating effect of the reaction would be considerable. The access of heat produced in this way would in turn enable the magma to perform a further amount of work in the way of mechanical solution. 2. A saturated or oversaturated magma (i.e. one which on solidifying would give rise to a saturated or oversaturated rock) is incapable of combining chemically with silica; its action on the quartz of invaded rocks must be confined to physical solution, which will lower thie temperature of the magma. Other things being equal, then, an undersaturated magma must have a greater action upon invaded siliceous rocks than a saturated or oversaturated magma; as a result of such action it would tend Dr. Shand—Saturated & Unsaturated Igneows Rocks. 511 first to saturate itself chemically, then to oversaturate itself in the physical way. (Reactions with constituents other than silica are for the moment disregarded.) As a consequence of the greater activity of an undersaturated magma, one would expect to find greater variation, both chemical and mineralogical, within a body or complex of undersaturated rocks than in a saturated or oversaturated body or complex. This deduction seems to be confirmed by the enormous number of varietal names which have been coined for different facies of the undersaturated rocks. 3. Towards the aluminous constituents of invaded rocks it would seem that there would be little difference in the behaviour of saturated and undersaturated magmas. ‘he change by which aluminium silicates are converted into micas and felspars, a change for which the field evidence is overwhelming in amount, could not be effected any more readily by a felspathoidal magma than by : a felspathic one, since in both felspars and felspathoids the ratio of Na, K: Alisthe same. This particular conversion must be due to an excess of alkali in the magma, of which no trace remains as such when the rock has solidified and become exposed to investigation. With this point, however, I am not at present concerned. There remains the theoretical possibility that aluminium silicates might be reduced to corundum by reaction with an undersaturated magma. 4. When the invaded rock is a carbonate or other non-silicate rock, or contains much lime, magnesia, or iron in the form of oxide or carbonate, then the advantage as regards absorbing power lies with the saturated and oversaturated magmas, which can yield first their excess of silica, and secondly a further quantity of silica due to the reduction of sodium, potassium, calcium, and magnesium molecules from the saturated to the unsaturated state. In this way a saturated or oversaturated magma may become undersaturated. This case, as regards alkaline rocks, has been presented by R. A. Daly.’ The above deductions involve no assumption at all as to the extent to which absorption takes place in nature; so long as even a few instances arise in which absorption is admitted to have taken place, then it becomes necessary to recognize the essential difference in the absorptive capacity of saturated and undersaturated magmas. The appearance of, let us say, nephelite in a syenitic rock means far more than the mere addition of another name to the list of accessory minerals present in the rock; it involves a real difference, both of kind and degree, in the reaction of the magma towards its environ- ment. By studying the distribution of the saturated and under- saturated members of an igneous complex one may gain a wider view of the process of differentiation than is to be had from the study of minute mineral and chemical differences alone. With these considerations in view, it is instructive to turn to the distribution of oversaturated and undersaturated rocks in the lithosphere. 1. As regards mere bulk, the oversaturated and saturated rocks predominate enormously over the undersaturated. Daly’ estimates ! ' ** Origin of the Alkaline Rocks’’: Bull. Geol. Soc. Amer., 1910. 512 Dr. Shand—Saturated & Unsatwrated Igneous Rocks. that ‘‘all the visible alkaline rock of the world probably constitutes less than 1 per cent of the total visible igneous rock’’. If in addition to the alkaline rocks we consider the olivine, melilite, melanite, and corundum-bearing rocks, it seems likely that the total mass of the undersaturated rocks will scarcely exceed 2 per cent of the total visible igneous rock. 2. Among major intrusions the vast majority consists of over- saturated rocks. Saturated rocks have a much smaller representation, and undersaturated rocks are relatively rare except as marginal facies and differentiated bodies. Where nephelite-syenites occur they are in surprisingly many cases associated with limestones, and Daly* makes out a good case for regarding some of them, at all events, as due to absorption of lmestone. Thoroughly unsaturated types (e.g. dunite) never form truly major intrusions. 3. Among lavas and minor intrusions the oversaturated types are quite subordinate to the saturated and undersaturated. Thoroughly unsaturated types, though rare, are recognized in dunites and some monchiquites and alndites. Undersaturated types, such as nephelite and leucite tephrites, basanites, and basalts, olivine dolerites and basalts, picrites, peridotites, and serpentines, are well represented. 4. A curious point, which will, I think, survive the test of. statistics, is the very frequent occurrence of undersaturated and unsaturated rocks in the pipes of single-explosion volcanoes. The olivine bombs of the Dreiser Weiher and other volcanoes of the Kifel and Auvergne, and the ultrabasic agglomerate with content of olivine and pyrope which fills the pipes of some of the volcanic necks of Scotland, will serve to illustrate this point, but the most superb examples are the kimberlite and alndite pipes of South Africa. Kimberlite, with its abundant olivine and pyrope, and its possible melilite,? is emphatically undersaturated ; while some of the alndites, as described by Rogers,’ are entirely unsaturated. These observations can be reduced to the following form: Those igneous rocks which have been brought up most rapidly from the earth’s interior, and have solidified most rapidly in or on the crust, are to a marked extent undersaturated. Those others which have slowly worked their way up into the crust (and have hence had abundant opportunity for absorbing silica) are found to be pre- dominantly oversaturated. We have here a strong suggestion that undersaturation may be characteristic of the deeper zones of the lithosphere, as oversaturation is of the higher. I do not wish to insist upon this point, but merely to show that the distinctions employed here have their uses even in the discussion of the major problems of geochemistry. The conceptions of saturation and undersaturation are capable of application to the classification of igneous rocks, and provide just those natural distinctions between different types, the absence of which petrographers have been accustomed to deplore. If writers 1 “* Origin of the Alkaline Rocks’’: Bull. Geol. Soc. Amer., 1910. 2 Carvill Lewis, 1897; Mennell, 1909. > Trans. S.A. Phil. Soc., 1904; Ann. Rep. Geol. Comm. (Cape of Good Hope), 1911. Dr. Shand—Saturated & Unsaturated Igneous Rocks. 5138 like Dr. Hatch! and Mr. Mennell,? who tie their faith to silica percentages, would instead employ the mineralogical dividing lines which separate the oversaturated from the saturated rocks, and these again from those which are undersaturated (1) with regard to leuco- eratic constituents, (2) with regard to melanocratic constituents, and from (8) those which are undersaturated or unsaturated in all their constituents, they would find themselves in possession of a much more ‘natural’ classification of rocks, and one which would be vastly simpler to use than any classification which is based upon silica per- centages. The connexion between mineral and chemical composition need not be obscured thereby, but rather the reverse, especially if, as could easily be done, the relative degrees of oversaturation or under- saturation were introduced as subordinate factors in the classification. The fact that, under different conditions of temperature and pressure, one and the same magma may give rise to rocks of different degrees of saturation, is an argument in favour of my contention, not against it. The classical experiment of Fouqué and Michel-Lévy, in which a melt of orthoclase and biotite yielded leucite and olivine on cooling, illustrates this point. The silica percentage, being the same in the product as in the educt, fails to express the difference between these two very different mineral associations ; yet the former is saturated, the latter unsaturated, and by making degree of saturation a criterion of systematic position we effect a separation of things formed under unlike conditions, which is at least as important as the separation of things of unlike ultimate composition. If Dr. Hatch and Mr. Mennell had considered the natural criterion of undersaturation, in place of the artificial one of silica percentage, they would not have been led into the paradoxical positions of classifying borolanite, a rock which typically contains neither plagio- clase nor augite, with ‘‘alkali-gabbro” and ‘“ dolerite”’ respectively. In my opinion both these gentlemen have erred by committing themselves to classifications which are neither definitely chemical nor definitely mineralogical. A chemical classification, to be of any value, must have regard to all the molecules present in a rock, not to one alone. If a classification is to be mineralogical, let it be consistently so. I believe that both chemical and mineralogical classifications are necessary, but of hybrid classifications I would go so far as to say, as Harker says of hybrid rocks, ‘‘ like other hybrids, they are barren.” The recognition of the essential difference between saturated and undersaturated rocks ought to lead to the avoidance of such loosely- used terms as shonkinite, monzonite, and essexite. We read in Dr. Hatch’s textbook, forexample, that ‘‘nepheline and leucite occur occasionally in monzonites’’; that essexites contain a variable quantity of nepheline; and that nepheline and sodalite ‘‘may be present in small quantities’? in shonkinite. The older petrographers always drew a sharp distinction between the syenites and the nepheline- syenites ; however small the proportion of nepheline, it was considered sufficient to justify the removal of the rock from the former to the 1 Textbook of Petrology, 1909. 2 Manual of Petrology, 1913. DECADE V.—VOL. X.—NO. XI. 33 514 T. Crook—The ‘Shrinkage’ of Septaria. latter class. The same procedure, with regard to olivine, is followed to this day in the application of the names tephrite and basanite, nephelinite and nepheline basalt. The distinction between the saturated and the unsaturated minerals is a real one, with important consequences in the chemistry of rock magmas; and petrographers who shut their eyes to a natural distinction of this kind deserve the fate that awaits them at the hands of inventors of arbitrary classifications. The present paper is an argument for the importance of the above distinction, and a plea for its recognition in petrographic nomenclature. VI.—Serrarra: A Derence oF THE ‘SHRINKAGE’ VIEW. By T. Crook, A.R.C.Se. (Dublin), F.G.S. CONTRIBUTION to the March number of the GuxonoatcaL Macazine by Dr. A. M. Davies, and another in the August number by Mr. J. E. Todd, support. a view formerly held by Professor H. G. Seeley, viz. that the cracks of septaria are due to expansion, during growth, of the outer layer of the nodule. For several reasons this view appears to me to be untenable. It seems to be based on an erroneous conception of what takes place during the growth of a septarian nodule. It exaggerates the signi- ficance of crystallizing force in material deposited from solution. In a rudimentary way a nodule is a crystalline growth, but the manner of this growth speaks of a force of crystallization that has been thwarted and not allowed free play. A nodule is of the nature of an imperfectly crystalline precipitate, rather than a robust crystalline growth. It consists of a mass of shapeless microcrystalline granules, each of which was presumably deposited from solution in such a way as to accommodate itself quietly to the surface on which it grew. Surely Mr. Todd makes a mistake when he compares the crystallizing force of material deposited from solution to the expansive force manifested by water in solidifying. There is no analogy between the two processes. I think we are justified in asserting that the growth of a septarian nodule in a clay has at least this in common with the growth of a crystal from solution: it presents a sharply defined surface to the medium in which it is growing, and it grows by addition of material to the surface. And if material can be deposited on the faces of a growing crystal without the interior being ruptured by the crystal- lizing force when that force displays its full vigour, why should the addition of shapeless and accommodating microcrystalline granules to the surface of a growing nodule result in internal rupture ? Moreover, nodules are septarian only when they have incorporated within their substance a considerable amount of colloidal clayey matter. Ifa nodule consists of fairly pure carbonate, or if it contains sandy matter to the exclusion of clay substance, it does not become septarian. How is this fact explained by the ‘ expansion’ view ? Again, I fail to see how we can allow the last added shell of the nodule to crack the enclosed mass without cracking itself; and if the outer shell did expand during growth without cracking itself, T. Crook—The ‘ Shrinkage’ of Septaria. 515 the process would probably result in a series of concentric cracks infilled with calcite, rather than in radiating cracks. There is really no evidence that the cracks develop during growth in this way; and until some proof is forthcoming that crystallizing force acts in the way suggested, it seems more reasonable to adopt the view that the cracks arise from shrinkage subsequent to growth. This shrinkage view seems to be well in accordance with the facts, and accounts for the results in a more satisfactory manner. In explaining the formation of the cracks by shrinkage, it is important to note that the rate of radial growth of a nodule probably diminishes very rapidly as the nodule increases in size. If we assume, for the sake of argument, that its shape is spherical, then the surface area of the growing nodule increases as the square of the radius. It follows, therefore, that the surface of deposition when the nodule is 10cm. in diameter is 10,000 times greater than it was when the diameter was 1mm., and 100 times greater than it was when the nodule had a diameter of 1 cm. Not only is there this tremendous rate of increase in the surface of deposition during the growth of the nodules: there is also a decrease in the dissolving surface; for the particles of less stable carbonate from which the solution maintains its supply are continually diminishing in size as the nodules grow. Until the contrary is proved, it is reasonable to infer from these facts that the rate of radial growth diminishes enormously as the nodule increases in size. If so, its substance during growth will gradually increase in com- pactness from the centre outward; and the last-formed layers will probably be very much more compact than the first-formed layers. We should expect that the first-formed part of a nodule would incorporate more argillaceous material than the portions formed later. Mr. Todd states that this is not the case; but his statement is not convincing. At least we may assume that the argillaceous material of the earlier-formed portion is much wetter than that of the later- formed portion of the nodule. We may still conclude, therefore, that the internal mass of the nodule consists of wet argillaceous carbonate, and that it is surrounded by an outer shell of drier and more compact material. The nodule in this state will, like the enclosing sediment, continue to suffer from the compacting process. It will lose water, and shrink. The more compact outer shell will suffer little tangential contraction. The contraction of the wetter interior will be more considerable, and will be accommodated by a shrinkage of the mass on the outer shell. This will result in the development of radiating cracks, which may ultimately become filled with calcite. I see nothing in the facts so far adduced that invalidates this explanation. It is singular that so little has been done in the way of investigating the facts bearing on this subject, and that so much has been left to speculation. Until a fuller investigation has strengthened the case against it, I for one shall continue to hold the ‘shrinkage’ view. 516 Notices of Memoirs—British Association— NOTICHS OF MEMOTRS. Abstracts of Papers read in Section C (Geology), Meeting of British Association, Birmingham, September 10-17, 1913. 1. On varrous OccurRENcEs oF Pittow Lavas 1n North anp Sourn Wates. By A. Husperr Cox, M.Sc., Ph.D., F.G.S., and Professor O. T. Jones, M.A., D.Sc., F.G.S. Pillow lavas were described from four localities, viz. :— (a) Strumble Head, in Pembrokeshire. (6) Cader Idris, in Merionethshire. (c) Sarn Mellteyrn, near Pwllheli, Carnarvonshire. (d) Careg, 2 miles N.N.W. of Aberdaron, Carnarvonshire. (a) Strumble Head (A. H. Cox).—References were made particularly to the work of Reed and Elsden. The rocks were formerly regarded as intrusive, and were described as of composite characters and possibly of later date than the main folding. Variolitic rocks were described by Reed, who referred to the ‘pillow structure’ as ‘spheroidal jointing’. The whole mass appears to consist largely of highly vesicular, basic flows, some with well-developed pillow structure, others showing transitions to non-pillowy types. Abundant chert occurs in association with the lavas, particularly those showing pronounced pillow structure. The most perfect pillows vary from a foot to 18 inches in diameter, and consist of typical spilites, with thin, rod-like felspars of refractive index about 1°542, corresponding to oligoclase—the rocks are con- siderably decomposed, especially to calcite, chlorite, and epidote. Among the above rocks are ophitic diabases, showing marked columnar jointing, which may in part represent sills. (6) Cader Idris (A. H. Cox).—A thick band of pillow lavas forms the highest point of the Cader Idris range, and then strikes W.S.W. Its distribution is described in detail, and reference is made to the work of Ramsay and Geikie. A comparison of these rocks with those of Strumble Head discloses certain differences, especially in their uniformly less vesicular character and smaller amount of associated chert. Under the microscope the rock shows the character of a typical spilite; both rod- and lath-shaped felspars occur, the former being oligoclase, the latter somewhat richer in soda (refractive index below 1°541). The rock is considered to resemble most closely that of Mullion Island. In close association with it is the ‘ Eurite’ (soda-granophyre) of Cole and Jennings. These lavas appear to occupy a stratigraphically higher horizon than the beds which yielded Didymograptus bifidus and D. murchisoni to Lake and Reynolds. The detailed examination of the area is still incomplete. (c) Sarn Mellteyrn (O.T. Jones).—References were made to the work of various authors, viz. Ramsay, Harker, Raisin, Elsden, Matley. The rocks are exposed by the roadside three-eighths of a mile south- west of Mellteyrn Church, where 10 to 12 feet of typical pillow lavas overlain by a similar thickness mainly of non-pillowy rocks of allied characters are followed by flinty mudstones and micaceous shales. Abstracts of Papers read on Geology. 517 The spaces between the pillows are occupied by closely-jointed dark- grey chert. The sediments dip to the east at a moderate angle, and probably pertain to the lower part of the Arenig. The pillow lava is finely vesicular and considerably decomposed ; the felspar is oligoclase and forms lath-shaped microliths. From its structure and mineralogical character the rock is referred to the spilitic suite. (d) Careg, near Aberdaron (O. T’. Jones).—These rocks have been described in detail by Raisin, and the pillow structure noted as ‘spheroidal structure’. The present notes are intended to supplement that description in certain respects. The pillow structure is seen near Careg quarries and near the coast; individual pillows have a length of about 2 feet, and are composed of a fine-grained rock with small vesicles. The felspars have the extinction-angle and refractive index of oligoclase-albite, and are highly charged with decomposition products. These rocks are undoubted spilites, and were claimed as such by Dewey and Flett ; they are associated with ‘ limestones’ of a peculiar character, together with beds and strings of jasper, which in places wrap round the pillows in the same manner as the chert near Sarn. The association of that rock with a pillow lava may perhaps be regarded as confirming Greenly’s suggestion that the jaspers of Anglesey were originally cherts. The associated rocks at Careg have an extraordinarily complicated structure, and probably belong to the pre-Cambrian. 9. Onriricat Srcrions oF THE CAMBRIAN AREA CALLED THE Cwms IN tHE Carapoc—Cominy Reeion or Suropsuire. By EH. BS. Coppotp, F.G.S. /Y\HE work of excavation of critical sections in the Cambrian rocks of Shropshire has been continued by the writer at intervals during the past year, and has furnished paleontological proofs of the prolongation of the Lower and Middle Cambrian rocks of Comley into the Cwms area to the south. The sections opened up confirm and amplify those excavated in previous years. Excavation No. 58 supplies details of the upper portion of the Wrekin Quartzite and the lowest part of the Lower Comley Sandstone, near the base of which three fossiliferous bands are found, yielding species provisionally referred to Kutorgina, Hyolithus, Hyolithelius, and Archeocyathus. _ Excavation No. 54 exhibits a section of the junction of the Middle and Lower Cambrian beds, which is very closely comparable with those of the Quarry Ridge at Comley. The beds in descending order are as follows :— e. Shale with Grit Bands = The aaa, Ridge Shale, top not ft. 4 seen : é d. Hard, ringing, glauconitic Grit = = The Quarry Ridge Grit : 28 c. Conglomerate = The Quarry Ridge Grit, conglomeratic portion 9 b. Dark Grey, Purplish, and Red Limestones= The Black, Grey, and Olenellus Limestones of Comley : about 4 | a. Green, Micaceous Sandstones, ah spotted bands= The Lower Comley Sandstone; base not seen : : : 10 518 Notices of Memoirs—British Association— The conglomerate c is plentifully charged with fragments of the Black and other Lower Cambrian Limestones, and it is now proved for the first time that the Black Limestone must be grouped with the Lower Cambrian. Thesurface of the solid Black Limestone is coated witha phosphatic(?) skin, and a similar deposit in the Comley Quarry has within the last two or three years yielded recognizable fragments of Paradoxides sp. and Dorypyge Lakei, Cobbold. The black skin must, therefore, be regarded as the lowest deposit of the Middle Cambrian age that is known in the district. Among the numerous fossil fragments that occur in the Lower Cambrian Limestones of this excavation the following have been identified: Anomocare(?) pustulatum, Cobbold, Callavia Callavet, Lapworth (?), Mcrodiscus Attleborensis, S. & F., sp., Protolenus sp., Kutorgina sp., Linnarssonia (?) sp. , Excavation No. 55 exhibits a faulted junction between the Middle and Lower Cambrian, the hard, ringing Grit (beds d above) being brought into contact with the Green, Micaceous Sandstone (beds a above). Excavation No. 56 proved the existence of both the Quartzite and the lower part of the Lower Comley Sandstone at another point in the area. A section constructed embodying the results of these excavations provides evidence that the Lower Comley Sandstone has a thickness of about 480 feet. 38. HsruerrA 1N tHE Bonrer or Sovurm Srarrorpsuire.! By T..C. Canter, B:Se.,'F:G:8. ECORDS of fossils in the British Bunter are few in number, and some are open to doubt in respect either of their organic character or of the stratigraphical position of the beds that yielded them. Omitting those cases where the horizon formerly supposed to be Bunter has been corrected later and is now accepted as settled, the following appears to be a complete list, in chronological order of their discovery :— 1. Dictyopyge catoptera (Ag.), a small fish, from Rhone Hill, 3 miles south-east of Dungannon, co. Tyrone. Upper Bunter (f*). With this was associated Estheria portlocki. 2. ‘Annelid tracks’ at Hilbre Point, Wirral, Cheshire. Lower part of the Bunter Pebble Bed (f*). 3. Plant-remains, referred to Schizoneura paradoxa, Schimper and Mougeot, at Sneinton Vale, near Nottingham. Uppermost bed of the Bunter Pebble Bed (f?). To these three older records can now be added the following new discovery ' :— 4. Estherta cf. minuta (Alberti), from Ogley Hay, near Walsall, South Staffordshire. Bunter Pebble Bed (f?). * Communicated by permission of the Director of the Geological Survey. Abstracts of Papers read on Geology. 519 These fossils were discovered in May, 1911, when Mr. C. H. Cunnington and I were mapping the Triassic rocks bordering the eastern side of the coal-field. I suggested to my colleague that if fossils could be found anywhere in the Bunter they would most likely be discovered in the thin marl-bands occasionally interbedded in the predominant sandstones and conglomerates; and Mr. Cunnington’s hammer was the first to reveal the specimens. We obtained them from two thin bands of red marl in a disused sand-quarry at Ogley Hay, 5 miles north-east of Walsall. The quarry forms a conspicuous excavation in the northern face of a sandstone hill, along the foot of which passes the Anglesey branch of the Wyrley and Essington Canal. The hamlet of New Town, on the Watling Street, lies 150 yards to the north of the quarry, while Ogley Hay Chemical Works stands 200 yards away to the south-east. Below a little drift gravel are exposed 22 feet of dull-red medium- grained soft sand-rock, in places false-bedded. ‘Toward the bottom -are two bands of red marl, about 1 ft. 8 in. apart, the lower one being about 2 feet above the bottom. They nowhere exceed 9 inches in thickness. Both marl-bands yielded poorly preserved remains, determined by Mr. H. A. Allen as Hstherva cf. minuta (Alberti). The ground is coloured on the old series 1 inch map (62 N.E.) as Upper Bunter (f*); but the sandstones are coarser and duller in colour than the typical Upper Bunter of other Midland districts, and would more suitably be included in the outcrop of the Pebble Beds (#*). The Triassic series dips at 3° to 5° toward E.N.E., in which direction the Pebble Bed subdivision appears to pass laterally into, and partly beneath, finer-grained and brighter-coloured sandstones that may be regarded as Upper Bunter. Above these follows the Lower Keuper Sandstone (f°). There is thus no question as to the beds in the quarry being Bunter, and every ground for referring them to the Pebble Bed subdivision. 4, Tue Retation or tHE Rutwias anpd Bata Limestrones at Bata, N. Watses. By Dr. Gerrrupe L. Exzezs. HE difficulties in the interpretation of the succession in the Bala district appear to be due largely to the impersistent nature of the limestones and their inconstancy as to horizon. The succession is as follows :— Hirnant Limestone (impersistent). HIRNANT SERIES + Hirnant Flags and Mudstones. Rhiwlas Limestone (impersistent). Bala Limestone (impersistent). Caleareous Ash. Mudstones. Coarse Ash. Mudstones and flags with thin impersistent Limestones. Ash. Sandy flags, with occasional impersistent Limestones. Ash. Sandy flags becoming shaly towards base. The Rhiwlas Limestone is an impersistent limestone at the base of the Hirnant Series, and is found only in the northern part of the BALA LIMESTONE SERIES 520 Notices of Memoirs—British Association— area. The Bala Limestone is not developed as a calcareous bed in the northern part of the area, but is somewhat more persistent as a definite band in the southern and eastern portions of the district. The true relations of these horizons to each other is seen in the type section at Gelli Grin, where the Bala Limestone at its maximum thickness is overlain by light-coloured, pasty mudstones containing a typical Rhiwlas Limestone fauna. The fauna is not nearly so rich in individuals as that of the Rhiwlas Limestone itself, but all the more important genera and species seem to be represented. Confirmatory sections are also seen east of the fault near Gelli Grin Farm, and also on Bryn Cut. 5. Tue SHetty anp Graproriric Faunas oF THE BRITISH Orvovician. By Dr. Gerrrupe L. Extzs. f eerie are two main types of ‘shelly’ faunas of Ordovician age in the British Isles, and each of these can be further subdivided into a number of sub-faunas which can be correlated by reference to associated graptolite-bearing beds. ORDOVICIAN FAUNAS. | Graptolitic Shelly Graptolite Zones A B Zone of Cephalog. acuminatus Staarode pial meses fauna Zone of Dicellog. anceps Exotic fauna . 4 Zone of Dicellog. complanatus Calymene _ plani- lz ip eet ons marginata fauna | Exotic fauna . 3 one of Pleurog. linearis Tih eames Zone of Dicranog. clingani es Rea . Powisi a Sas eat Ye estat Zone of Climacog. Wilsoni Zone of Climacog. peltifer Exotic fauna . 2 Ogygia Buchi fauna with Asaphus tyran- nus sub-fauna Zone of Nemag. gracilis Zone of Glyptog. teretiusculus Exotic fauna . 1 Zone of Didymog. Murchisoni Placoparia fauna | Zone of Didymog. bifidus | Zone of Didymog. hirundo Ogygia Selwyni fauna Zone of Didymog. extensus | Zone of Dichograptus The main shelly types may be described as— A. Asaphid-Trinucleid-Calymenid fauna. B. Cheirurid-Lichad-Encrinurid fauna. Abstracts of Papers read on Geology. 52) Evidence suggests that fauna B is an exotic fauna, possibly southern in origin, which migrated into the British area. Becoming early established in South Scotland, it soon spread west into Ireland, but did not dominate the whole British area till Ashgillian times. 6. Tue Basat Carsonirerous Beps at Lyn, In SourH SraFrFoRDSHIRE. By W. Wicxuam Kine, F.G.S., and W. J. Lewis, B.Sc. N the Grout. Maa., Dec. V, Vol. IX, p. 437, 1912, we announced if (inter alia) that purple beds of Lower Old Red age existed at Saltwells. Since then we have ascertained that 2 miles to the south, at Lusbridge Brook, Lye, below the Thick Coal, Carboniferous beds are exposed for a thickness of nearly 400 feet as against about 200 feet at Saltwells. These basal beds are difficult to interpret. The succession below the Thick Coal in Lusbridge Brook is thus : (a) Various Clays and Coals, 280 feet; (b) Conglomerate, 27 feet; ‘(¢) Red Clays (Plants) and White and Yellow Clays, in which are embedded many pieces of quite unworn Cherts, and at base Limestone Grits and a Conglomerate, thickness 40 feet; (d) White, Red, and Yellow Clays. (d) is only exposed for about 30 feet. Total below Thick Coal, 377 feet. Mr. F. G. Meachem has kindly given to us data proving that the beds down to the base of (0) are the same thickness in the Freehold Pit, Lye, and that there, below (6), they pierced Red Marls for 150 feet. The interesting zones are those in which the Limestone Grit and Cherts occur. Broken fossils occur in the Limestone Grit, which is made up largely of angular pieces of Limestone. In the Conglomerate _() a pebble 18 inches in diameter of highly calcareous grit containing Calamites varians has been found, which is probably another type of this Limestone Grit. A precisely similar calcareous grit was found in situ at or below (6) in the Freehold Pit, and above (c) a nearly similar type occurs in the form of gigantic slabs 2} feet thick in the Lye Cemetery. The Cherts contain many casts of fossils, but they are so imperfect that we hesitate to name them. We found in the clays (¢) a minute fragment of a Brachiopod with a straight hinge-line. Pebbles of ae alia) Limestone Grit and Cherts occur in the Conglomerates. The Limestone Grits, Cherts, and Clays at Lye are such as might be laid down in the vicinity of a shore-line and there disintegrated in situ. In several respects they resemble the Rush Conglomerates of Lower Carboniferous age in Ireland. Compare Q.J.G.S., vol. lxu, p. 285. In the Conglomerates there is distinct evidence of Inter- Carboni- ferous denudation which removed in places, as at Saltwells, the Coal-measure Ironstone (Neuropteris), Coal Seams, Grey Limestones, Limestone Grits, and Cherts. In Q.J.G.S., vol. lv, p. 123, 1899, Mr. King showed that all the pebbles in the Permian Conglomerates of the Severn Basin are referable to a local source, except only those of Lower Carboniferous age. The last-mentioned pebbles contain Syringopora and Caninia. 522 Notices of Memoirs—British Association— Some of the pebbles that he regarded as of Lower Carboniferous age are identical lithologically with the Limestone Grits and Cherts now found at Lye. In Permian times the Lower Carboniferous Rocks provided, from original and derivative local sources, much of the material in the Permian Calcareous Conglomerates. 7. Tur Devetopment or THE Mipitanp Coat-Fietps. By Frep- G. Meacuem, M.E., F.G.S. REAT advances have been made in mining since the first meeting of this Association in Birmingham in the year 1839. Women were then employed in the mines, also children under 10 years of age, and all worked twelve hours or more in the pit. To-day women are not allowed to work in a mine, and no youth under 14 years, and the hours of labour are restricted by Act of Parliament to eight per day. Nearly all the mines worked in 1836 were shallow ones, and the output not more than 200 to 300 tons per week. The area of the coal-tields was about as shown below, as against the present known and concealed areas of coal. Year. South Staffs. Leicester. Warwick. Salop. Total square miles. 1836 f 70 20 10 20 120 Uh 360 88 222 96 766 This last calculation includes the concealed coal-field between Chasetown, Aldridge, and West Bromwich on the west and the Warwickshire and Leicestershire Coal-fields on the east, and also the concealed coal-field between Cannock, Essington, and Stourbridge on the east of the Coalbrookdale and Forest of Wyre Coal-fields on the west. The output since figures are available is as follows :— Year. South Staffs. Leicester. Warwick. Salop. Total in million tons. 1865 10 4 j 1s 13 RSF tek Bae 74 22 4h 3 154 This shows a great advance in industrial conditions and in Economic Geology, but the question of output does not show so great an increase ; this I think is due, not to fear that the concealed coal-fields would not be profitable, but to the fact that some of the deeper mines have not proved remunerative. This is partly due to local conditions in the mines and also to the fact that the deeper coal costs more to get than the shallow coal, as regards actual working cost and the greatly increased capital needed, whilst the coal from both — mines is sold in the same market, so that the shallow mine rules the selling price. As afew years pass by, and probably before the next meeting of this Association, the shallow mines will be exhausted, and the prices will be ruled by the deeper mines, with the usual economic results of increased prices in proportion to increased costs to get. In the figures above, areas are included which were not thought of in 1836, but, as is fully shown by the report of the last Royal Coal Commission, 1905, coal will undoubtedly be found in the areas above named. The area between the South Staffordshire Coal-field and the Leicestershire and Warwickshire Coal-field will be found to be Abstracts of Papers read on Geology. 523 one continuous coal-field, with its deepest part at Lichfield, Sutton Coldfield, and Coleshill, but the basin rising to the south asa whole, the thick coal of Sandwell and Hamstead will split up into two or three seams, and under these conditions will be worked Longwall, with better commercial results. The area between the Staffordshire Coal-field and Shropshire has been most vigorously investigated, and the proofs at Colwich, Huntingdon, Essington, Four Ashes, and Baggerridge show that this area is going to be rich in coals of good quality and laid down under conditions that will allow of remunerative working. On the Shropshire side very little has been done to extend that coal-field to the west of either the Coalbrookdale or the Forest of Wyre Coal-fields; the edges of the Old Red Sandstone preclude any hope of extension, but in the Highley and Kinlet and Billingsley area it is most probable that future deeper sinkings will prove deeper coals than the two seams at present working, whilst the area to the east is full of promise. As soon as the Severn Valley Fault, which is some 300 to 400 yards downthrow east, is crossed, a new coal-field will be found, and I think the area between here and the old coal-field will be divided into two basins, with a Silurian anticline between them as proved by the Claverley boring. 8. ON ‘THE OCCURRENCE oF A WinD-worn’ Rock-suRFACE AT LittesHatt Hitt, Satop, anp or Wuinp-worn SToNES THERE AND ELSEWHERE. By Frank Raw, B.Sc., F.GS. ILLESHALL HILL, lying some 53 miles north-east of Wellington, and extending north-east and south-west, is a ‘hogsback’ of Uriconian, and is largely bare rock. The exposed rock of its south- _east side consists towards the north-east of very hard halleflintas, interstratified with somewhat softer tuff, and to the south-west of this and opposite the Monument of still harder felsite conglomerate and grit. . Practically the whole of this rock-surface has been ground smooth and, where hardest, has been highly polished, the smooth surface being traceable everywhere except where it has obviously been removed by weathering or quarrying. The surfaces of projecting masses of the conglomerate are perfectly fresh, being ground smooth, deeply fluted, and polished as by wind- blown sand, the radiating flutings showing the paths of escape of the prevalent ‘wind. To the north-east the rock-surfaces have been much more even, perhaps based on a previously glaciated surface, and the flutings are parallel and in that direction less and less highly inclined, till at the north- east end they lie at an inclination of 15° to 20° up to the north in north and south planes. From the south-west end of the wind-worn surfaces already described similar polishing can be traced across the hill to the north-west on the steep rock-surfaces of quartz-veined halleflintas which bound on the south-west the highest part of the hill. South-west of this the crest of the hill is fairly flat and covered with grass. Here two reservoirs have been constructed for the 524 Reviews—Geology of Newton Abbot, South Devon. Lilleshall water supply, and several of the stones thrown out were found to be beautifully wind-worn and polished. Two trial excava- tions made near by yielded a considerable proportion of wind-worn stones embedded in fine soft red sand. In one of the excavations carried to a depth of 29 inches there also occurred immediately beneath the turf a definite layer of white even- sized wind-worn sand, the grains measuring about 345 inch in diameter, above the fine red sand with wind-worn stones. The occurrence of wind-worn stones is also recorded from other localities in the Midlands, and specimens in illustration are exhibited, 9. Puanr Perriracrions IN CHERT AND THEIR BEARING ON THE OriGin oF FresHwater Currts. By Marie C. Sropzs, D.Se., Ph.D. HE author described, and illustrated with photos, petrifactions of plants in the freshwater cherts of Lulworth (Purbeck) and Asia Minor (Tertiary). The author drew special attention to the Asia Minor cherts, which are remarkably interesting and contain well- preserved plant debris. These were described by Mr. Haydon in his _ presidential address to the Liverpool Biologival Society, but his work seems not to have reached most geologists and paleobotanists. The cherts contain beautifully preserved pollen grains, fungi, stem debris, etc.; and the existence of these delicate soft tissues so well preserved suggests that Sollas’s view of flint formation can only be apphed with caution to these freshwater cherts. The author drew attention to the recent ‘Sapropel’ observed by Potonié, and the likeness it has to the debris in the Asia Minor chert ; concluding that the chert may be taken as practically pure petrified ‘Sapropel’, a phenomenon which must interest those who are concerned with the methods of plant petrifactions. RAV Le wis- I.—GroLocicaL SURVEY OF A PART OF SoutH Dryon. Tue Grotocy or THE Country arounD Newron Assor. By W. A. E. Ussner, F.G.8.; with contributions by Cremenr Ruerp, F.R.S., J. S. Frerr, D.Se., F.R.S., and D. A. MacAtister, A.R.S.M, 8vo; pp. vi, 148, with 3 plates and 14 text-illustrations. London: printed for H.M. Stationery Office, 1918. Price 3s. fY\HE country described in this memoir is a highly interesting and picturesque portion of South Devon, wherein are to be seen the fossiliferous Devonian limestones of Bradley Woods and elsewhere near Newton Abbot, and other Devonian strata with interbedded and intrusive igneous rocks; the Culm Measures with chert-beds and fossiliferous shales at Waddon Barton, near Chudleigh, and intercalated igneous rocks to the west, including portions of the Dartmoor granite at Lustleigh. Then the coast is dominated by fine cliffs of Red Rocks, ranging in upward succession from the Permian terra-cotta clay of Watcombe through the bold masses of conglomerate and breccia, sandstone and marl which extend to Teignmouth, Dawlish, and Exmouth. Beyond is the famous Bunter pebble-bed of Budleigh Reviews—Geology of Newton Abbot, South Devon. 525 Salterton, with overlying Bunter and Keuper Sandstones. Attractive also are the fossiliferous Upper Greensand outliers of the Haldon Hills, with their coverings of gravel grouped as Kocene; likewise the . thick and varied deposits of the Bovey Basin, including the plant- bearing lignites and the pottery clays (now regarded as Upper Oligocene), and the overlying gravels and alluvial deposits, some undoubtedly Pleistocene, others of Holocene or Recent age. This great series of formations is well shown on the new colour-printed map, Sheet 339 (price 1s. 6d.), but the Pleistocene gravels have not been indicated in the Bovey Basin. The area in fact, as stated by the Director, Dr. ‘Teall, in his preface, was to a large extent re-surveyed in 1874 and subsequent years on the old 1 inch map, particularly as regards the Permian and newer strata. This work was transferred to the new series map and published in hand-coloured form in 1899, considerable revisions having been made in the Paleozoic areas by Mr. Ussher. Still later revisions are included in the colour-printed edition of the map, and the mineral lodes have been inserted by Mr. D. A. MacAlister. The coloured section at the foot of the map is taken (perhaps wisely) to the north of the Bovey Basin, from the granite near Hennock, through Chudleigh, across Great and Little Haldon, and over the Red Rocks to Exmouth and East Budleigh. An area containing so much of interest has naturally attracted many geologists, and among the early workers Godwin-Austen (then Austen) was conspicuous. Residing for a few years (from about 1831) at Ogwell House, near Newton Abbot, he prepared a geological map of the country, published in an elaborate and philosophical memoir in 1842 by the Geological Society; but the results of his field-work were given by Austen to De la Beche, who utilized them in the original Geological Survey map, Sheet 22, which was published in 1834. Of other workers H. B. Holl, and subsequently Arthur Champernowne, devoted much time to geological mapping, while J. K. Lee, G. F. Whidborne, Dr. Henry Woodward, Dr. G. J. Hinde, and Mr. Howard Fox added much to the knowledge of the palaontology of the older formations. It is remarkable, however, considering the careful account given of the literature, and the list of published papers, that no mention is made of the ‘‘ Notes on Parts of South Devon and Cornwall’’ by J. B. Jukes (Roy. Geol. Soc. Ireland, 1868). In that paper Jukes records a meeting with Dr. Holl in a quarry near Newton Abbot, when he ‘‘laughingly remarked to him that ‘one might toss up whether the beds were vertical or horizontal’, for there were planes of division in both directions, either of which might be planes of stratification and the other joints’’. To Mr. Ussher, who commenced work in the area in 1874, we are indebted for the elucidation of the main structure of the area, as regards not only the Devonian and Carboniferous,, but also the Permian and Trias. His main conclusions on the older rocks were given in a paper published by the Geological Society in 1890. He now amplifies the information and gives details of the Devonian and Carboniferous subdivisions. It is observed that ‘‘as a whole the impersistence of the Devonian limestone is clearly proved, but direct 526 Reviews—Geology and Forestry. evidence is wanting as to the original extension of the limestone in. individual districts”. While mostly of Middle Devonian age, certain parts of the limestone ‘‘may represent the Cuboides-stage of the Continental Upper Devonian’’. The higher portion of the Upper Devonian is represented by the Gonzatites-intumescens-stage at Lower Dunscombe. The names of the Devonian fossils collected during the course of the survey have been revised by Dr. Ivor Thomas. It is noted that in the Lower Culm Measures the chert-beds seem to be developed on different horizons, ‘‘immediately beneath the Posidonomya-beds and perhaps to some extent intercalated with them,” and at lower positions down to the local base of the series. The interbedded and intrusive igneous rocks of the Devonian and Carboniferous are described by Dr. Flett, who calls attention to the occurrence of spilites showing excellent ‘pillow-structure’ near Bickington. Schalsteins and quartz-keratophyres are likewise described. The intrusive rocks include diabases, proterobases, picrite, and portions of the Dartmoor granite, with felsites, Accounts are given of the contact alteration produced by the diabase sills, and of the metamorphic aureole bordering the granite. The Permian rocks, including the basalt of Dunchideock, and the Trias are described by Mr. Ussher, and the Upper Cretaceous by Mr. Reid, who has naturally relied on Mr. Jukes-Browne for most of the particulars.’ In transcribing ‘‘his account with a few modifications’, it would have been well to have used inverted commas for the quotations, and to have inserted the modifications within brackets. The Eocene and Oligocene deposits are described by Mr. Reid, who gives his reasons for separating the Eocene, and presumably Bagshot, gravels of Haldon from the similar gravels at a lower level in the Bovey Basin. Much has yet to be done in following the connecting links between the Bagshot gravels of Black Down near Portesham in Dorset and the South Devon deposits. Details are given of the Bovey Beds, with list of plants, the majority of which have been determined by Mr. and Mrs. Reid to be ‘* identical with species found in the well-known brown-coal deposits of Germany. These are now generally accepted as the highest Oligocene strata, though certain authorities class the Aquitanian stage as lowest Miocene”’. The remaining portions of the memoir contain accounts of caverns and fissures, river gravels and head, recent changes, water supply, metalliferous deposits, building-stones, clays, ignites, ete. There is one plate of photomicrographs of igneous rocks, and another showing much-weathered Triassic sandstone resting on the Budleigh Salterton Pebble-bed. { II.—Grotogy anp Forestry. URING the past few years the subject of afforestation has attracted more and more attention, and considerable areas of gathering ground connected with waterworks, as well as some tracts rendered barren and unsightly by tips from mines and quarries or by 1 Memoir on Cretaceous Rocks of Britain, vol. i, 1900. Reviews—Progress of the British Musewm. 520 furnace refuse, have been successfully planted. Larger schemes for woodlands, more directly intended for economic purposes, are under consideration, and as their success depends fundamentally on geological considerations, on soil and substrata, on ground-water and drainage, which affect available plant-food, it is well that geologists should give some attention to the subject. We are glad, therefore, to see an article on ‘‘The Use of Geology to the Forester’ (Trans. Foresters and Gardeners Society of Argyll for 1912, 1913), by Dr. C. B. Crampton, of the Geological Survey of Scotland. He emphasizes the need of giving attention to the horizontal and vertical distribution of the various rocks and soils, and their relations to the physical features. The formation of soils and subsoils on different types of rock is briefly explained; descriptions are given of screes, landslips, rain-wash, pan, etc.; and there are notes of trees and shrubs suitable for certain situations, having regard to geological, physiographical, and climatic conditions. Special reference is made to the Scottish Highlands and to the effects of glaciation, whereby old soils were removed and large tracts rendered infertile, the results being summed up as ‘‘a baring of glaciated unweathered rock surfaces at all levels—a smothering of wide areas by sterilised and more or less impermeable boulder clay, and the piling up of loose glacial debris and leached sands and gravels”. Extensive areas of this transported material, however, are under cultivation by the agriculturist, but as a rule they would not be suitable for plantations without the benefit of tillage. While some of the Geological Survey maps, especially those of the old hand-coloured editions, ‘‘form but a framework so far as the needs of the forester are concerned, since they give little indication of the presence or nature of subsoils and soils,’ it should have been added by the author that for South Wales and for many Midland and Southern counties of England, there are a number of published and many more MS., six-inch geological maps (copies of which can be purchased) that show in detail the superficial deposits. Moreover, even the published one-inch drift maps have been found by Mr. A. D. Hall and Dr. EK. J. Russell to be of essential service in their important soil researches; and such maps are now issued by the Geological Survey of Scotland.! Iit.—Awnnvat Report or tHE British Museum ror 1912. Pp. 212. H.M. Stationery Office, 1913. Price 103d. net. VHE annual return, which made its customarily tardy appearance at the end of the summer, some seven months after the close of the year to which it refers, contains beneath a forbiddingly statistical air a great deal of interest, and is eloquent testimony to the important work being done by the expert staff at both branches of this great institution. Considerably more than half the number of pages are taken up with the Natural History Museum, and it is with these that we are mainly concerned here. We are glad to note a recovery from the great drop in the number of visitors reported in the previous year, though the numbers still remain some way below ' See GEOL. MaG., 1911, p. 377. 528 Miscellaneous. those chronicled for 1910, and it is encouraging to notice a steady increase in the number of visits paid for purposes of study. The appointment of an official Guide to take members of the public round various parts of the museum daily, free of charge, has been much appreciated, and evidently meets a widely felt want. It is to be hoped, too, that the example of the parent institution in putting on sale picture postcards or other reproductions of objects of interest in the museum will be followed at South Kensington; such means of drawing attention to the museum and therefore of increasing its usefulness are not to be disdained. The rapid growth of the entomological collections and the importance of insects in relation to the spread of disease in man and in animals have led to the separation of the Entomological Section from the Zoological Department, and Mr. C. J. Gahan, formerly senior assistant, has been made the first Keeper of Entomology. So great is the congestion in the collections on this side of the museum that an extension of the building westward is under consideration. Dr. Jehu gave his fourth course of Swiney lectures in December and January, his subject being ‘“‘The Record of Life as revealed in the Rocks”. His appointment has been extended for another year, and he proposes to give a course of lectures in December on ‘‘ The Natural History of Minerals and Rocks”’. 1V.—Untrep Srares Geotoctcan Survey.—Water-supply Paper No. 292 (1918) continues the account of the surface water-supply, as part xii, North Pacific Coast. In No. 314 (1918) the ‘‘ Surface Water-Supply of Seward Peninsula, Alaska’’ is described by Messrs. F. F. Henshaw and G. L. Parker, and included in the report are a sketch of the geography and geology by Mr. Philip 8. Smith, and a description of the methods of placer mining by Mr. Alfred H. Brooks. The subjects are well illustrated by a geological map; a topographical map, on which are marked the gauging and rainfall stations and the placer deposits; and numerous pictorial views of flumes and other artificial water channels, and of mining operations andsluicing. In Water-supply Paper No. 317(1913) Mr. C. H. Gordon reports on the ‘“‘ Geology and Underground Waters of the Wichita Region, north-central Texas”’. MISCHLLAN HOUS. Av a meeting of Council in September, 1918, Dr. F. H. Hatch, M. Inst. C.E., F.G.S., ete., was duly elected President of the Institution of Mining and Metallurgy for 1914. Dr. T. F. Sibly, F.G.S., Lecturer in Geology in King’s College, London, has been appointed Professor of Geology in University College, Cardiff. Mr. I. Sheppard, F.G.S., Curator of the Municipal Museums, Hull, has been elected President of the Yorkshire Naturalists’ Union for the ensuing year. 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VOL xX. 4 No. XII.—DECEMBER, 1913. ORIGINAL ARTVICLHS. Oo J.—On a New Specimen oF tHe Cretaceous Fish Porrayzvs | MOLOSSsUS, COPE. By ARTHUR SMITH WOODWARD, LL.D., F.R.S. (PLATE XVIII.) EVERAL nearly complete skeletons of the primitive teleostean S fish Portheus molossus are now known from the Chalk of Kansas’; but none is better preserved than a remarkable trunk, nearly 12 feet in total length, lately obtained for the British Museum by Mr. Charles H. Sternberg. The specimen is shown, of about gz of the natural size, in the accompanying Plate XVIII, where it is seen mounted with the head of another fish of the same proportions. All the bones remain embedded in the matrix exactly as they were found, and there is no restoration beyond slight repairs. The vertebral centra in the fossil form a continuous undisturbed chain from the pectoral arch backwards, only damaged a little by erushing. The total number of dorsal vertebrae is about fifty-five, while that of the caudals is thirty-three. From the pectoral arch backwards to the caudal fin all the centra are impressed on the side by two deep longitudinal depressions, of which the upper is the larger. In a few of the anterior centra the lower lateral depression is especially small, and restricted to the hinder half. ‘he lower face (well seen in some of the distorted anterior centra) is flattened between the two longitudinally extended pits in which the bases of the hemal arches are fixed. The gently arched ribs are long and slender, all reaching the ventral border of the fish. Each rib is impressed by a slight longitudinal groove, and its upper end is somewhat expanded where it fits loosely in the socket of a small parapophysis. This parapophysis, which does not appear to be firmly fixed in the pit of the centrum, is much more expanded in front of the socket than behind, and is in direct contact with the adjacent parapophyses. The arrangement is well shown in a drawing by O. P. Hay,? in which it was originally mistaken for a neural arch. In the anterior half of the abdominal region in the fossil the neural arches are accidentally removed, but further back several are in place, 1 A. R. Crook, Paleontographica, vol. xxxix, p. 109, fig. 1, 1892; H. F. Osborn, Bull. Amer. Mus. Nat. Hist., vol. xx, pp. 377-81, pl. x, 1904; CG. EK. McClung, Kansas Univ. Science Bull., vol. iv, p. 243, pl. xii, 1908. 20. P. Hay, Zool. Bull., vol. ii, p. 47, fig. 12, 1898; corrected in Bull. Amer. Mus. Nat. Hist., vol. xix, p. 56, 1903. DECADE V.—VOL. X.—NO. XII. 34 530 Dr. Arthur Smith Woodward— and there are a few scattered examples. Like the hemals, they are loosely inserted in pits which extend nearly the whole length of the centra. As shown also by Hay,’ each arch consists of a pair of thin lamine, right and left, loosely apposed in the median plane, and surmounted by a long and slender neural spine, behind which a smaller and shorter rod-like process also rises upwards. Each arch slightly overlaps or clasps that next following, but without so well- defined a facet as that represented by Hay. Above some of the neural arches there are remains of the curved free fin-supports. In the caudal region both the neural and hemal arches are firmly fixed in the pits of the vertebral centra as*far as the origin of the caudal fin. Though longitudinally extended at their base of insertion, they do not overlap or interlock, but the tail is strengthened by the sharp backward curvature and inclination of all the neural and hemal spines. The base of each neural arch is a little triangular expansion, strengthened by a vertical lateral ridge, but not bearing any posterior process, and not in contact with the next arch of the series. The base of each hemal arch is shaped almost like the parapophysis in the abdominal region, but the heemal spine is directly continuous with it.2 The hemal arches within the caudal fin are much thickened, in close contact, and articulate with the corresponding centra in open sutures. There are no intermuscular bones in the caudal region or below the vertebral column in the abdominal region ; but some may perhaps occur among the confused remains in the dorsal part of the abdominal region. The left clavicle is seen from within, and exhibits the characteristic long and slender precoracoid arch crushed upon its inner face. Below it the base of the left pectoral fin appears, showing the bases of the four stout anterior rays in their natural position, The same rays of the right pectoral fin are well displayed lying over the ribs, the longest equalling in length a chain of about eighteen vertebre. All these rays are gently arched bony rods, flattened on the outer face and marked only with a few longitudinal striations, evidently due to their structural fibres. The first, second, and fourth rays appear to be nearly complete to their distal end, where they scarcely taper and lack all traces of transverse articulations. The first ray is the stoutest and largest, with a sharply though irregularly rounded anterior border; the second ray is at least half as wide as the first ray, and its slender distal end, split by crushing, is preserved in the fossil to a greater length than the latter; the third ray, though seen on the left, is restored on the right side, but it is clear that its distal end cannot have been much expanded; the fourth ray is less stout, and shorter than the others. Behind these rays in another specimen in the British Museum (No. P. 10611) the pectoral fin is completed by three or four very short rays, which expand distally into a finely divided and articulated portion. The pelvic fins are preserved apparently in their natural position, arising beneath about the forty-eighth vertebra. They are less than 1 0. P. Hay, Zool. Bull., vol. ii, p. 51, figs. 15, 16, 1898. 2 See figures by O. P. Hay, Zool. Bull., vol. ii, p. 48, figs. 13, 14, 1898 (in which the hemal arch is described as neural, and vice versa). On a Chalk Fish from Kansas. 531 half as long as the pectoral fins—a proportion very different from that observed in the restored paired fins in the specimens at New York and Lawrence (Kansas). The pelvic bones, which are well shown, are firmly articulated in the middle line at their base, and correspond in shape with those originally ascribed to Portheus by Cope.t The first fin-ray is much stouter and larger than the others, but it expands a little towards its distal end, and must have been finely divided and articulated at its extremity. The whole fin, in fact, resembles that of another specimen in the British Museum (No. P. 6326) which has already been figured.’ Of the median fins, the dorsal and anal are only imperfectly preserved, but the remains suggest that these fins were arranged as in Ohirocentrites* and the living Chirocentrus, not as in the restorations at New York and Lawrence (Kansas). The anal fin clearly arises at the beginning of the caudal region, where both the fin-supports and the bases of the fin-rays are seen in nearly undisturbed ‘series. It is uncertain, however, whether this fin extended as a low fringe backwards—it can only be noted that a few displaced short and broad fin-supports in the hinder part of the fossil may have belonged to such an extension. The dorsal fin is represented only by a few supports and imperfect rays at some distance behind the origin of the anal, and it seems probable that if it originally extended further forwards or backwards some traces would be exhibited. The deeply forked and powerful caudal fin is already well known, and the new specimen confirms previous descriptions. There is clearly no sudden termination of the vertebral column with a urostyle as in Chirocentrus; but the five or six hindmost vertebree form an upturned series, rapidly diminishing in size, as in the Elopines and other primitive teleostean fishes. Remains of large and thin scales occur in various parts of both the abdominal and the caudal region, and their outer face often exhibits an irregular coarse tuberculation like that of the opercular bones. The rounded tubercles do not appear to be enamelled. The new specimen of Portheus now described, while confirming previous descriptions in many respects, is thus of importance as showing for the first time the relative proportions of the paired fins and the probable true relationship of the dorsal and anal fins. It has already been pointed out that there are striking resemblances between Portheus and Chirocentrites, and the facts now published concerning the fins make it doubtful whether the species belonging to these two categories can any longer be referred to two distinct genera. EXPLANATION OF PLATE XVIII. Portheus molossus, Cope; nearly complete trunk, with the head of another individual; about » nat. size. Obtained by Mr. Charles H. Sternberg from the Niobrara Chalk of Kansas, U.S.A. (Brit. Mus. No. P. 11125.) 1 B.D. Cope, Vert. Cret. Form. (Rep. U.S. Geol. Surv. Territ., vol. ii, 1875), p. 192, fig. 9. 2 A. S. Woodward, Foss. Fishes English Chalk (Mon. Pal. Soc., 1907), p- 101, fig. 28. 3 J. J. Heckel, Denkschr. k. Akad. Wiss. Wien, math.-nat. Cl., vol. i (1850), p. 203. See also A. S. Woodward, Foss. Fishes Hnglish Chalk, p. 99, fig. 25. 532 R. D. Oldham—Origin of the Himalayas. IIl.—TwHe recent Discussion oN THE ORIGIN OF THE HIMALAYAS. By R. D. OLDHAM, F.R.S., V.P.G.S., etc. VHE discussion on the origin of the Himalayas, started by Sir T. H. Holland’s review! of Colonel Burrard’s memoir, appears to have been led, by the concluding sentence of that review, into an un- profitable channel; for alike in the review and in the succeeding articles by Mr. Fisher* and Colonel Burrard? it seems to have been accepted that only two theories are applicable, firstly, Mr. Fisher’s discussion of the theory of the disturbed tract contained in chapter x of the first and chapter xiii of the second edition of his Physics of the Earth's Crust, and, secondly, that developed by Colonel Burrard. Further, it is assumed that the former is dependent on the hypothesis of a fluid earth and the latter such as should follow from the hypothesis of a solid, highly heated, and cooling globe ; the connexion, in either case, being so close that the acceptance of one or other hypothesis, of the constitution of the earth, necessitates the acceptance of one and the rejection of the other of the theories of the origin of the Himalayas. This, however, is not the case; Mr. Fisher’s treatment of the disturbed tract, though originally a development of his theory of a fluid earth, and quite consistent with it, is equally consistent with the hypothesis of a solid earth, for it is hardly conceivable that the substance of the most solid of globes would not yield and flow under stresses of the magnitude and duration of those involved by the support of a mountain range such as the Himalayas, and, once such a flow commenced, there would be developed a system of quasi-hydrostatic support, and an isostasy caused by a species of flotation, which is all that is demanded by the general theory or by the adaptation to the particular case of the Himalayas contained in chapter xviii of the second edition of the Manual of the Geology of India. I, at least, have never regarded this as having any but a very remote bearing on the hypothesis of a solid or fluid condition of the interior of the earth. On the other hand, Colonel Burrard’s explanation, so far from being in accord with the hypothesis of a solid, cooling, earth, is in reality inconsistent with it, and his view, that, in such a globe, rifts would open by contraction from the surface downwards, is the reverse of what would actually take place. The conditions existing in a partially cooled solid globe are well understood; I believe they were first pointed out by Mr. Mellard Reade in 1876, but once indicated they became a truism, and may be very briefly explained. In such a globe there would be, on the outer surface, a crust, which has fully cooled and is incapable of further contraction, and in the centre a heated core, to which cooling has not penetrated; between the two lies a belt of material which is gradually losing heat and contracting in bulk. At the inner limit the contraction of this layer 1 Sir T. H. Holland, ‘‘ Origin of Himalayan Folding ’’: GEoL. MaG., 1913, p. 167. 2 Rey. O. Fisher, ‘‘ Rigidity of the Earth,’? Grou. MAG., 1913, p. 250; “Origin of Mountains,’’ GEOL. MAG., 1913, p. 434. 3 Colonel S. G. Burrard, ‘‘ Origin of Mountains’’: Grou. MAG., 1913, p. 385. R. D. Oldham—Origin of the Himalayas. 583 of cooling material must cause tension, as a diminution of the circumference is resisted by the uncooled central core; at the outer limit, where no further cooling takes place, the consolidated crust would be thrown into compression by the reduction in bulk of the material below, and somewhere between these two would come a zone where the radial and tangential contractions exactly balance each other, so that the material would neither be compressed nor extended. The depth at this level of no strain beneath the surface would depend on the initial temperature of consolidation and the temperature gradient. The latter is approximately known, the former is doubtful; Mr. Mellard Reade, assuming a temperature of about 3,000° F., calculated the depth at about 1 mile; later, Mr. Fisher calculated a depth of about 0:7 mile for an initial temperature of 4,000° F., and of 2 miles for an initial temperature of 7,000° F. Of these three values for the initial temperature the lowest is the most probable, and the calculations show that any rift, which might be formed by tension in the ‘ sub-crust’, could not reach the surface ; _ it would originate at the level of the greatest tensional strain, which would lie at between 30 and 50 miles below the surface, and thence extend upwards and downwards, but could not reach upwards to within about a mile from the surface. These calculations never had any geological interest, beyond showing that the hypothesis of an originally highly heated, and gradually cooling, solid globe afforded no sufficient explanation of the structure of the earth’s outer crust, as revealed by geological observation in the field; they have been rendered of little more than academic and historic interest by modern researches in radio-activity, which have, incidentally, provided a means by which fissures opening at the surface of the earth and penetrating downwards could be produced; for if the earth is an originally cold globe, getting gradually warmer, and expanding in bulk, by the action of radio-active material, then such fissures would naturally be formed; but in that case none of the consequences which Colonel Burrard has drawn from his rift would follow. In all this I have not been arguing for or against a fluid or a solid earth, but against the introduction of an irrelevant issue. Whether the earth is a fluid orasolid globe seems a matter which concerns the astronomer, the physicist, or the mathematician, much more than the geologist; for all the processes which his observations demand appear to be equally compatible with either hypothesis. Nor am I arguing against Colonel Burrard’s explanation as a whole; it may stand with the others as a possible hypothesis, to be tested and examined on its merits, but the tests must mostly be of a nature quite unconnected with geological observation. When, however, Colonel Burrard postulates the existence of a rift, or narrow band of subsidence, reaching 20 miles deep from the surface, we are brought face to face with a phenomenon for which we have no precedent, and before accepting it we must be satisfied, not only that it explains the geodetic facts, but that no other explanation, in closer accord with what is known of the geology of the regions, can be found. No one can gainsay Colonel Burrard’s contention that geologists must take count of the facts of geodesy, but it is equally true that 534 R. D. Oldham—Origin of the Himalayas. geodesists must take count of the facts of geology, and in either case a distinction must be drawn between the facts of either science and the conclusions of individual workers, and again between those direct and inevitable deductions, which have almost the value of observed facts, and the more remote inferences, which may represent only one, or a part of one, of the possible explanations. Bearing this in view I propose to review, very briefly, the facts and explanations on either side. On the geodetic side the facts may be summarized by taking the two stations Kurseong and Jalpaiguri, 25 miles apart, the first situated on the edge of the Himalayas, the second out in the Gangetic alluvium. At Kurseong the observed deflexion of the plumb-line is 46” to the northwards; the calculated effect of the attraction of all visible masses, after allowance is made for the effect of isostasy, should have produced a deflexion of only 23”, leaving an unexplained residual of 23” northerly deflexion. At Jalpaiguri the observed deflexion is only 1” to the northwards; the calculated deflexion should have been 8” to the northwards, leaving an unexplained residual of 7’ southerly deflexion. It may be well to point out that the values, both of the observed deflexions and of the unexplained residuals, depend on the assumed dimensions of the earth. The figures quoted are deduced from the dimensions now accepted by the Great Trigonometrical Survey of India as the nearest approach which has been made to exact accuracy, but, although the acceptance of different values for the size of the earth would alter the figures, no admissible variation would make a material change in the difference between them. For instance, if the earlier values, based on the Everest spheroid, are adopted, the observed deflexions at Kurseong and Jalpaiguri become 51” and 6” to the north and the unexplained residuals 28” to the north and 2” to the south, still leaving a difference of 30” as between the two stations, which cannot be explained by the ordinary methods of geodetic calculation, and is only to be accounted for by some local peculiarity, or departure from average conditions. The explanation offered by Colonel Burrard is a deep and narrow rift, filled with material of less density than average rock, and situated between the two stations ; there can be no question that the explanation is a feasible one, so far as the mathematics are concerned,! for the diminished attraction caused by the replace- ment of denser by less dense material would cause an apparent repulsion on either side of the rift, but before accepting this as the only,. or even as the probable, explanation, we must see whether another cannot be found, in better accord with the known facts of geology. The geological facts, which are pertinent to the question under consideration, may be simply expressed. All along the southern face of the Himalayas runs a great fault, or series of parallel faults, known as the boundary fault, on the north of which le the older rocks of the Himalayas, and on the southern the upper Tertiary 1 It may be added that a much lesser depth than 20 miles would not satisfy the conditions. R. D. Oldham—Origin of the Himalayas. 535 Siwaliks of the sub-Himalayas and the alluvium of the Gangetic plain. The Siwaliks were long ago shown, by Mr. H. B. Medlicott, to have been formed from the waste of the Himalayan range, under exactly similar conditions, and by the same rivers, as the alluvial deposits of the Gangetic plain, in other words to be merely the lower, older, and marginal, deposits of the same formation, now uplifted and exposed to denudation. The throw of the boundary fault cannot be measured directly, but it is certainly great, and may reasonably be estimated at between 10,000 and 15,000 feet, say between two and three miles. It may exceed or fall short of these limits in places, but is not likely to do so to any material degree. On its southern margin the alluvium thins out over an old land surface. Between the two margins nothing can be determined, by direct observation, of the form of the rock floor, but the most natural deduction is, that the thickness of alluvium gradually increases from south to north, reaching its maximum at the great boundary fault, ‘so that the Gangetic trough may be regarded as having the form of a very acute-angled wedge lying on its side, with the thick end towards the north. Mr. H. H. Hayden has recently shown that the pendulum observations of the Indian Survey support this interpre- tation,! but whether this exactly represents the case or not it is certain that the northern limit of the Gangetic trough is nearly vertical and of a depth of two or three miles, while at the southern limit the thickness of the alluvium is very small. The effect on the direction of the plumb-line of a depression of this size and shape, filled with material which cannot have a density of more than 2-2, must be considerable, and I have had the curiosity to investigate it. The detailed results of the investigation would take up too much space to reproduce them here, nor are they suitable to this Magazine, but the general result may be indicated. I find that at the northern limit of the plain the effect would be an apparent repulsion of the plumb-bob, or in other words an apparent excess of attraction by the Himalayas, amounting to about 30” if the depth of the alluvium is taken at 3:5 miles, and 18” if it is taken at 1:75 miles. These values are not materially affected by any variation in the width of the alluvium. On either side of the boundary fault the deflexions decrease rapidly, but more rapidly to the south than on the north, for whereas, at 20 miles from the boundary on the north, there is still a deflexion of some 5” or 6” to the northwards, the northerly deflexion has almost disappeared at the same distance to the south, to be replaced, still further south, by a southerly deflexion, or apparent repulsion away from the Himalayas. I have only indicated here the general nature of the effect which would be produced, but enough has been said to show that both in kind and magnitude it is very similar to that which has been observed, and for the explanation of which the 20 mile deep rift has een offered. Kurseong hes about 2 miles north of the main boundary fault, Jalpaiguri les in the region where southerly deflexions should be expected, and the difference in deflexion, as 1 Rec. Geol. Surv. Ind., xliii, pt. ii, pp. 163-7. 536 B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. between the two stations, due to the effect of the less dense material filling the Gangetic trough, could not be less than 20” and might amount to over 30”. From this it appears that without going beyond the known facts of the geological structure of the region—facts which are independent of any theory of the origin of mountains or the constitution of the interior of the earth—we can account for nearly, if not quite, the whole of the unexplained residual deflexions, which, instead of amounting to 23” and 7”, would not come to more than 3” or 4”, and the difference of 30” would disappear or, at the least, be reduced to one of a few seconds of are. In all that has gone before I have avoided the question of the origin of mountain ranges in general, or of the Himalayas in particular, as, although I entered on the investigation, which I hope to publish in detail, with the hope that the limit of fairly established deduction might be carried further into the domain of pure speculation, I have found that the geodetic results do not give any material assistance. They have confirmed some conjectural inferences regarding the form of the rocky bed of the Gangetic depression, but on the question of the origin of the Himalayas, and of the nature of their support, the evidence is too uncertain and equivocal to be of any material value. This much, however, seems certain, that there is no good evidence for the existence of a rift of 20 miles or so in depth, as, once the known facts of geological structure are taken into consideration, the existence of such a rift would explain too much and introduce fresh difficulties even greater than those for which it was introduced as an explanation. Moreover, we must add to this negative evidence the positive fact that every observer, in every part of the range which has been ‘visited, has found evidence of compression in precisely that zone where Colonel Burrard’s postulate demands extension. IJ1.—Tue Pruronic Rocxs or Garapat Hitt. By B. K. N. WYLLIE, M.A., B.Sc., and ALEXANDER Scott, M.A., B.Sc., Carnegie Research Scholars in the University of Glasgow. (Concluded from the November Number, p. 508.) T various places, such as the north side of Garabal Hill, the two A Garabal burns (loc. iv and v, Fig. 1), and elsewhere, remarkably coarse rocks are found. A good section showing an apparent passage from tonalite to a coarse hornbleniite is exposed at loc. v (Fig. 1). The rock in the bed of the burn is the normal tonalite, which appears to pass gradually to diorite. A closer examination of the unweathered rocks, however, shows that the passage is only apparent, and that the tonalite is clearly intrusive into the diorite with sharp junctions. The diorite near the junction is a rock of porphyritic aspect, con- taining large crystals of zoned diopside, abundant green hornblende and felspar, while the amount of quartz is small. A good deal of biotite is present, so that the rock might be described as a pyroxene- mica-diorite. Within a few feet the rock becomes coarser in texture, and the felspathic content diminishes, while there is a corresponding B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. 587 increase in the amount of amphibole. The latter is the green horn- blende common to the diorites, and is occasionally replaced by mosaics of secondary actinolite. This substitution of felspar by hornblende, accompanied by an increase in the coarseness of the texture, continues till a hornblendite containing about 85 per cent of amphibole is reached. ‘This rock is exposed for a distance of 20 yards to the south, and then the ground is obscured by peat, so that the other margin of the diorites cannot be seen. The hornblendite consists essentially of large crystals, more or less uniform in size and up to 3 cm. in length, of green hornblende which has wholly or partly altered to brown, the alteration commencing invariably from the centre. Occasional pyroxene cores are found, and these are generally surrounded by a narrow band of green amphibole, with brown beyond and finally green margins. The interstices are filled up with agereeates of quartz, felspar, and small green hornblendes, with occasional crystals of sphene. The finer-grained varieties of this ‘sequence probably resembled very much the hornblendite which occurs along with scyelite in the Moine Gneiss regions.’ Occasional schlieren, resembling those already described, occur among the coarser rocks. These are generally much more felspathic than the surrounding rocks and contain long prismatic hornblendes up to 6 cm. in length. The brown hornblende of this series differs considerably from that of the davainites. In the latter case the mineral has developed directly from pyroxene and is invariably brown, while in the former case it. has formed from original green hornblende, different degrees of trans- formation being visible, varying from incipient alteration at the centres to completely brown crystals. The mineral shows pleochroism from deep brown to yellowish green and has strong absorption. It is generally traversed by series of parallel dark bands arranged in lattice fashion and with small outgrowths, the whole somewhat resembling arborescent microlites. Teall? has described similar structures in amphiboles from Cornwall and Anglesey, and Thomson? also found them in hornblendites from Wicklow. In these cases the dark bands were assumed to be magnetite, formed by the magmatic resorption _of pyroxene and consequent replacement by hornblende. In the Garabal Burn rock a careful examination, under a high power, of the ends of the bands and outgrowths showed that they are composed of aggregates of minute pale-green or colourless crystals, orientated in irregular fashion with respect to the main direction of the bands. It seems probable that the whole of the dark bands are made up of these minute crystals, the black colour being analogous to that observed in some opaque glasses, where the opacity is due to innumerable colourless longulites, which act as prisms and disperse and totally reflect the light, the degree of opacity varying with the amount of light totally reflected.* 1 Geology of Ben Wyvis, etc. (Mem. Geol. Surv. Scotland), 1912, pp. 128-9. 2 British Petrography, 1908, pp. 475-94. 3 Quart. Journ. Geol. Soc., lxii, pp. 475-94, 1908. 4 Cf. Pirsson, ‘‘ Artificial Lava Flow and its Spherulitic Crystallisation ’’: Amer. Journ. Sci., ser. IV, xxx, pp. 97-114, 1910. 538 B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. GENERAL PrrTRoLoey. Excluding for the moment the tonalite, and also the possible relations between the diorites and the ultrabasic rocks, we propose to consider shortly the variations exhibited by each of these two groups. Although chemical analyses have not been made of all the rocks concerned, it seems most probable that there is no great variation in chemical composition in the ultrabasic series, save where impregnation by the latter acid intrusives has occurred. ‘The basic end-member is a pure olivine rock altered to serpentine, and with a composition approximating to that of olivine. The other end- member is the pyroxenite. The mineralogical ,variation could therefore be shown diagrammatically by two curves, one representing the increase of pyroxene—including hornblende—from zero to approximately 100 per cent, while the other would represent the decrease of olivine from 100 per cent to nearly zero. The chemical differences are so small, therefore, that it seems to us that local variations in the conditions are sufficient to account for them. That the intrusion did not take place all at one time is shown by the presence of the veins of porphyritic rock, the end-product of the consolidation of the magma. Hence, in a magma of such size, consolidating over a considerable period of time, the conditions could not remain uniform. Local variations in temperature and pressure would involve local partial consolidation, and therefore areas of lower potential, with the result that a potential gradient would be set up. This would be followed by intermagmatic chemical reactions, involving the formation of other molecules and resulting in local excesses of ortho- or metasilicate molecules, with an ultimate consolidation as olivine or pyroxene, as the case may be. A similar explanation would account for the variations of the diorites. Here again we have a comparative uniformity in chemical composition, the chief variation being in the mineralogical composition, in the substitution of pyroxene by hornblende and of hornblende by felspar and biotite. Supersaturation of the magma with respect to the ferromagnesian molecules would not occur everywhere at the same temperature, with the result that sometimes the high temperature modification, pyroxene, would form, sometimes the modification stable at lower temperatures, hornblende. The amount of water dissolved in the magma would also exert some effect, as the presence of water favours the formation of hornblende, in addition to reducing the viscosity. Local richness in potash would affect the production of biotite, while pressure would be an important factor owing to the probably high molecular volume of mica. A magma from which under certain conditions pyroxene would crystallize, would, under other conditions, give hornblende or biotite... Hence it seems to us that there exists no necessity to postulate any differentiation beyond what would ensue from a locally heterogeneous magma. We will now proceed to consider the Garabal Burn series in greater detail. The texture varies greatly, as in places chilled margins 1 Cf. Doelter, Neues Jahrb. fiir Min., pt. ii, p. 178 et seq., 1888; pt. i, p. 1 et seq., 1897. B.K.N. Wyllve & A. Scott—Plutonies of Garabal Hill. 539 which might almost be called aphanitic in structure, are found in contact with the schist, while elsewhere the crystals of hornblende average 3 cm. in width, such coarse rocks generally occurring some distance from the margins. Another significant feature is the dyke or boss-like form in which the hornblendites occur.’ It seems to us, therefore, that they may be regarded as the roots or cores of giant apophyses of the diorite projecting into the schist roof and now laid bare by denudation. The fine-grained margins would crystallize quickly and form an impermeable envelope, which would inhibit the escape of water and other mineralizers and favour the formation of hornblende. Hence these may be compared to pegmatites on a large scale, resembling the ‘ peridotite-pegmatites’ of Loch Garabal in the mode of formation, though the latter are on a much smaller scale. The abundance of hornblende also favours the pegmatite theory, as mineralizers such as water are essential for its formation. I. II. III. IV. Vv. I Il. Til. IV. Vv. Fic. 8. Variation diagram of rocks of loc. v. Note: Quartz and biotite curves are drawn with scale of ordinates doubled. The mineralogical variation in the rocks of this series 1s most easily shown by means of a diagram. A number of specimens were taken at approximately uniform distances from the tonalite and their mineralogical composition calculated by the Rosiwal method.” The hornblende increases from 7 to 84 per cent, while the felspar shows a complementary decrease from 70 to 5 per cent. Quartz, which is never very abundant, decreases to a minimum before the coarsest rock 1 Hornblendites with brown amphibole have been described by Wright and Bailey in Colonsay, forming the margin of a syenite intrusion: Geology of Colonsay (Mem. Geol. Sury. Scotland), 1911, p. 29. ; 2 No. 1 is an acid diorite from Meall Breac, while the others are from the Garabal Burn. 540 B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. is reached and then increases slightly, while the biotite curve, though more irregular, as is to be expected, is very similar. The hornblende and felspar curves tend to become horizontal at the ‘coarse’ end where a nearly uniform rock is reached. Since these rocks show no normative quartz, the latter has obviously been formed from silica which has undergone hydrolysis at high temperatures. The increase in the water content as the coarse rocks are reached favours this. The chemical composition, on the whole, dves not show any great variations. We have analysed a specimen of the diorite close to the tonalite (VI) and one of the coarse hornblendite (VII). VI. VII. Vila. VIII. IDS SiO, 52-83 53°29 50-3 47-5 62-6 TiO» 1-82 1-41 1-6 —— —- Als Os 11-74 8-81 8-5 15-6 Lezior Fe Os 6-66 4-68 5-2 2-6 1-2 FeO 6-13 6-66 7-7 7-1 3-3 CaO 8-05 8-99 10-0 9-8 4-6 MgO 6-41 9-07 10-2 11-7 3:7 KO 2-06 1-87 1-6 1-5 2-5 Naz O 2-67 3-21 3-2 1-4 — H20 1-20 1-51 USY/ — —- H.O- -20 “17 — 2-4 7 C Og nt. fd nt. fd. — — Po O; -08 tr. = ae ee VI. Diorite near junction with tonalite, Garabal Burn. VII. Hornblendite, Garabal Burn. Vila. Approximate composition of brown hornblende of hornblendite (VII). VIII. Diorite (very rich in biotite), Ben Damhain, anal. J. H. Player.! IX. Granitite (tonalite), Ben Damhain, anal. J. H. Player.’ Though the silica is more or less constant, the hornblendite is somewhat more basic; that is, magnesia and lime increase at the expense of the alkalis, while the alumina decreases. These differences, however, are not sufficient to account for the mineralogical differences, as the‘ norm’ of the hornblendite shows a considerable amount of felspar. Hence we must conclude that the amphibole contains a considerable amount of alkali and lime, since the pyroxene which occasionally forms the core of the hornblende crystals is diopside.. The amount of water has undoubtedly been an important factor in the production of the hornblende, though the relatively greater amount of magnesia must also have had an influence. Oricin oF THE Brown Hornsiende. The case is more difficult when we come to consider the alteration of the hornblende. There is no doubt that the mineral was originally green, and that the change originated from the centres of the crystals, unless in the case of those with diopside cores where a band of green 1 Teall & Dakyns, loc. cit., p. 115. 2 Thid.5.p: 105. B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. 541 amphibole generally occurs round the diopside. It likewise seems most probable that the alteration took place after consolidation. The simplest explanation would seem to be that the change is due to the oxidation of the ferrous oxide and consequent passage of the iron from the basic radicles to the acid ones, to form ferrisilicatés. The chemical analyses, however, are against this, as the hornblendite actually has less ferric iron than the diorite, while there is no reason to suppose that the brown colour of amphiboles is due essentially to ferric oxide: indeed, analyses of brown hornblende are recorded, containing only a small percentage of ferric iron. That the green hornblende is a metastable form is shown by the separation of the minute crystals of the dark bands. Since these are too small to be identified directly all that we can deduce respecting them is that they are probably monoclinic hornblende or pyroxene, since the rhombic modifications require special conditions such as would inhibit their formation in the solid state. Two explanations suggest themselves :— 1. The brown colour may be due to ultramicroscopic crystals of the same nature as those of the feathery bands. As has been stated above, the colour of pitchstones and other glasses is often due to minute crystallites, which are too small to be resolved under the microscope, and the only evidence of the presence of which is the brown colour of the glass. Many pitchstones, too, show two genera- tions of crystallites, one microscopic, the other sub-microscopic. Hence it is plausible to suppose that the brown colour of the hornblende has originated in this way, by. the formation of in- numerable crystallites of an order of magnitude lower than that of the crystals of the dark bands. The only effects on the pleochroism of the separation of such crystallites would be a uniform increase in the absorption, the difference for light waves traversing the crystal in different directions remaining practically constant, and a change in colour due to the total reflection of the light at the violet end of the spectrum. 2. On the other hand, the explanation may be that the metastable green hornblende breaks up into two more stable minerals, the minute crystallites of the dark bands and a brown hornblende. Analysis ‘No. Vila was obtained by deducting from analysis No. VII the amount of the various oxides which go to make up the other minerals in the hornblendite, quartz, orthoclase, andesine, and biotite, the amount of these present being calculated by the Rosiwal method. As these are only present in small amount, the error in assuming their composition as normal is negligible, and hence No. VIIa probably represents fairly closely the composition of the hornblende. Com- paring this with analysis No. VI, it is seen that the amphibole of the coarser varieties contains a much greater proportion of sesquioxides than that of the finer types, as not only does more of the alumina in the latter rocks form felspar, but the iron partly crystallizes as biotite. In addition, the minute crystallites are colourless or nearly so, and hence may be assumed to be salts of lime or magnesia, with the result that their separation is accompanied by an enrichment of the residual material in ‘total’ iron. Thus we would have the 542 BK.N. Wyllie & A. Scott—Plutonics of Garabal Hill. formation of an amphibole much richer in the oxides common to brown hornblende, accompanied by the separation of the bisilicates as the crystallites. There is very little difference between the optical properties of the two amphiboles. The extinctions are the same, as well as the positions of maximum and minimum absorption, the only difference being in the nature of the absorbed rays. Tue ‘‘ Newer Ieneous Rocxs’’. The series of plutonic rocks which has been intruded into the Highland schists after the latter had been foliated are included under the general name of the ‘‘ Newer Igneous Rocks”. These intrusions, which are probably of Lower Old Red Sandstone age, show consider- able lithological similarities. Granite usually composes the greater part, but diorites are of common occurrence, while ultrabasic rocks, on the other hand, are somewhat scarce. The only ultrabasic rocks which have been described are the peridotites of Garabal Hill, the kentallenites of Argyll,’ the scyelites of the Moine Gneiss regions,” and the peridotites of the Coyles and Glen Doll,* each of which is accompanied by picrites. It is only in the last-named localities that we have a suite of rocks at all resembling those we have described. This includes an olivine-enstatite rock (saxonite), an enstatite- picrite, a porphyritic diorite with green hornblende, and some acid diorites. This is apparently a series of intrusions of decreasing basicity, with some rocks formed by amalgamation due to the later intrusions. A peridotite which occurs along with scyelite in Ross- shire seems to resemble the Garabal Hill wehrlite, but the scyelite itself, as well as kentallenite, are totally unlike anything occurring elsewhere, and seem to be more or less abnormal. Wherever ultrabasic rocks occur in the Highlands they are clearly the earliest intrusion, and are usually followed by diorite and finally tonalite and granite. That some time elapsed between the various intrusions is certain, as all the evidence goes to prove that the peridotites were consolidated long before the diorites came up, and the latter had obviously crystallized before the granite intruded. Another significant feature is the absence of intermediate types: Thus at Garabal Hill we have nothing between the felspathic davainite, representing the least basic of the peridotites and with 43 per cent silica, and the hornblendites, the most basic diorite, with 49-52 per cent silica. Again, in Glen Doll, there is no rock intermediate between a picrite, containing a good deal of olivine, and a fairly normal diorite. A similar gap exists between the tonalite and diorite, for the acid diorite of Garabal Hill has about 54 per cent of silica, while the tonalite has never less than 62 per cent. Hence we have clearly three separate series of rocks, each more or less complete in itself and each showing not only the normal rock with slight 1 Flett in Geology of Oban and Dalmaily (Mem. Geol. Surv. Scotland), 1908, pp. 82-109. 2 Flett in Geology of Ben Wyvis, etc. (Mem. Geol. Surv. Scotland), 1912, pp. 126-9. * Barrow in Geology of Braemar, etc. (Mem. Geol. Surv. Scotland), 1912, pp. 73-83. B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. 548 variations, but also the products of final consolidations in the form of schlieren; the porphyritic pyroxenite veins of Loch Garabal in the ultrabasic series, the hornblendites and the felspathic diorite- pegmatites of loc. v (Map, Fig. 1) in the diorites, and finally the aplites and acid pegmatites associated with the last intrusion. For these reasons it seems to us exceedingly difficult to suppose that the whole of these rocks are ‘‘ the result of the differentiation of an originally homogeneous magma”’.’ Firstly, it is most improbable that a magma is ever in a state approaching homogeneity. Local variations of physical conditions as well as assimilation phenomena on the margins must be sufficient to keep the equilibrium hetero- geneous. Secondly, while it is undoubtedly true that the basic elements would crystallize out first, the crystals thus formed would tend to sink, so that the upper parts of the magma would be relatively enriched in silica. Thirdly, the absence of intermediate types militates against the differentiation theory. This is also an argument against any theory of assimilation, as we should then expect a perfectly continuous sequence. Again, it is obvious that an original ultrabasic magma can never assimilate enough schistose material to form a tonalite, as the schist is more basic than the tonalite, while on the other hand an original acid magma could never form peridotite. In addition, it seems to us that difficulties arise when we come to consider the mechanism of differentiation. The application of Soret’s principle® involves a large degree of diffusion and ignores, to some extent, the important role played by viscosity, so that its applicability is probably confined to marginal phenomena on a fairly small scale. Similar objections exist with regard to the principle of Gouy and Chaperon.? The difference of concentration between the top and bottom of a magma due to a gravity concentration of the heavy molecules in the dissolved state would be so small as to be negligible, unless the magma were of enormous depth.* It is most probable that gravity only operates on the heavy molecules where the latter form an immiscible liquid or have crystallized out. Hence it seems to us that a separate origin of the ultrabasic and the acid magmas must be postulated. While it is possible that the diorite has formed from the tonalite by assimilation, no such possibility exists with respect to the peridotites. It may be that the igneous material of the earth’s crust is stratified to some extent and that the pyroxenites, etc., originated in some ultrabasic infraplutonic zone similar to that postulated by Fermor.’ The almost invariable association of acid rocks with the earlier peridotites suggests that the former were forced up the margins of the earlier intrusions, which would constitute areas of crustal weakness and hence be the most ready outlet for the acid material. Any attempts to verify these ideas, however, are so much hampered by our 1 Teall & Dakyns, loc. cit., p. 117. 2 Ann. de Chim. et de Phys., ser. V, xxii, pp. 293 et seq., 1881. 3 Thid., ser. VI, xii, pp. 384 ef seq., 1887. 4 Cf. Lehmann, Molekularphysik, i, p. 483, etc., 1884. 5 “Garnet as a Geological Barometer’’: Rec. Geol. Surv. India, xliii, pt. i, pp. 44-5, 1913. 544 B.K.N. Wyllie & A. Scott—Plutonics of Garabal Hill. incomplete knowledge of magmatic phenomena that they must remain as theories, and nothing more, for the present. Nore on tHE Diortres or Guen Lepnock, Comrir. Numerous isolated patches of diorite occur to the north-west of Loch Lomond, but no intrusion of any size is met with, except in Glen Lednock near Comrie. ‘This occurrence is of interest because of the fact that the plutonic mass gradually passes to a hypabyssal variety of very similar composition. The plutonic rock is a fairly coarse biotite-diorite of uniform character, and is made up of mica, hornblende, felspar, quartz, and sphene, while magnetite, apatite, and zircon occur as common accessories. The mica is a deep-brown biotite with strong absorption, and is intergrown with a green horn- blende, which is generally very much altered to chlorite. The felspar is partly andesine, partly orthoclase, and has apparently undergone crushing to some extent. Sometimes it is enclosed by the ferro- magnesian minerals. Quartz is subordinate, while fairly large crystals of sphene occur occasionally. On the whole, this rock resembles the typical biotite-hornblende-diorite ‘of Garabal Hill, though it has suffered much greater alteration. The rock is very uniform, the chief variation being in the relative amounts of biotite and hornblende. Very occasionally, anorthoclase occurs in addition to the other felspars. The hypabyssal rock may be described as a diorite-porphyry, and has obviously formed as the result of quicker cooling of part of the magma. ‘The phenocrysts include felspar, hornblende, and sphene, and show a tendency to occur in glomeroporphyritic aggregates. The felspars seem to be orthoclase, though they are generally so much altered that their determination is difficult. The hornblende has usually been replaced by fibrous aggregates of a secondary blue-green amphibole resembling actinolite; while occasionally the alteration has gone further and chlorite has developed. Sphene occurs as granular aggregates, intimately mixed up with the hornblende, though sometimes larger crystals are found. ‘The groundmass is a micro-crystalline aggregate of quartz, felspar, biotite, hornblende, and granular sphene. “The amount of quartz is small, but areas rich in sphene occur locally. The ferromagnesian minerals are found as small irregular crystals, and are accompanied by numerous cubes of magnetite. These rocks bear a close resemblance to the so-called porphyrites of Argyllshire,' not only in structure but also in the presence of two generations of hornblende. Numerous veins of aplite occur in association with these rocks, differing, however, from those of Garabal Hill in some respects. The aplites of the latter area have granitic affinities, and are made up of quartz and alkali-felspar with subordinate muscovite. Those of Glen Lednock, on the other hand, are related to the syenite family, and contain orthoclase with abundant pious while quartz and plagioclase are subordinate. 1 Geology of Cowal (Mem. Geol. Sury. Scotland), 1897, p. 103; Hill in Geology of Mid-Argyll (ibid.), 1905, pp. 103-15 ; Flett in Geology of Oban and Dalmally (ibid.), 1908, pp. 96-102. Prof. Garwood—Calcareous Algce. 545 Obviously, we have here an intrusion of the same nature as the diorite intrusion of Garabal Hill, but differing from the latter by the fact that part has undergone more rapid cooling, and hence has formed te diorite-porphyry. Analogous rocks, however, occur in the Strath Dubh Uisge valley, where a few dykes of very decomposed felspar-porphyry outcrop. An occurrence of diorite apparently passing to porphyrite has been described from Loch Melfort,’ but the Geological Survey are of the opinion that the porphyrite is an earlier intrusion which has been altered by the diorite. In the island of Colonsay intrusions of augite-diorites have been found, grading to lamprophyres on the margins.* The junctions of the different types in Glen Lednock are very obscure, and hence the relations between the rocks cannot be ascertained. TV.—On vrHeE Inwerortant Parr PpLayED BY CaLcAREouS ALGm AT CERTAIN GEOLOGICAL Horizons, with SPECIAL REFERENCE TO THE Patmozoic Rocks. By Professor E. J. GARWOOD, M.A., V.P.G.S.® (Concluded from the November Number, p. 498.) (WITH FOLDING TABLE II.) Solenopora.—The discovery of this genus in the Lower Car- boniferous rocks of Westmorland is of considerable interest, as its occurrence here gives us some insight into the history of its wanderings between the time when we last recorded it in the Got- landian rocks of the Baltic area and its subsequent reappearance in the Lower Oolite of Gloucestershire. Whether it lived in the Baltic area during the Devonian and Carboniferous periods is, however, still unknown. The fact of its occurrence in the Caradoc, Carboniferous, and Jurassic rocks of the British Isles would appear to point to its existence not far off during the intervening periods. In Westmorland and Lancashire Solenopora occurs in considerable abundance near the local base of the Lower Carboniferous rocks, and contributes largely to the formation of limestone deposits. It is present wherever the lowest beds of the succession are exposed, as at Shap, Ravenstonedale, and Meathop, and must formerly have flourished over a considerable area. Though bearing a general resemblance, both in hand specimens and in microscopic structure, to the Ordovician and Jurassic forms, it has recently been shown by Dr. G. J. Hinde to be specifically distinct.* It occurs as small, spheroidal nodules up to an inch in diameter, having a markedly lobulate outline embedded in compact and usually dolomitie limestones, and it is occasionally associated with oolitic structure. When fractured it exhibits the compact porcellanous 1 Flett in Geology of Oban and Dalmally (Mem. Geol. Surv. Scotland), 1908, p. 69. ? Wright & Bailey, loc. cit., pp. 33-4. 3 Edited and slightly abridged with the author’s permission from the original Address as delivered at Birmingham, before Section C at the British Association meeting. 4 Grou. MAG., Dec. V, Vol. X, p. 289, 1913. DECADE V.—VOL. X.—NO. XII. 35 546 Prof. Garwood—Calcareous Alga. texture and pale brownish tint characteristic of other species of this genus, while weathered surfaces frequently show a concentric and occasionally a radially fibrous structure. The profusion of this form in Westmorland would lead one to expect its occurrence in other districts where the lowest Carboniferous zones are developed; but so far as | am aware, no such occurrence has yet been recorded. It may be of interest, therefore, to mention here that a few years ago my friend Mr. P. de G. Benson brought me a specimen of rock from near the base of the succession in the Avon Gorge, which on cutting I found to contain several examples of Solenopora identical with the Westmorland form. Mitcheldeania.—The specimens of Mitcheldeania Nicholsoni originally described by Mr. Wethered were obtained from Wadley’s Quarry, near Drybrook, Mitcheldean, from the Lower Limestone shales near the base of the succession. Professor Sibly, who has recently made a careful study of the Lower Carboniferous succession in the Forest of Dean,' has traced this algal layer over a considerable area, and considers it to represent an horizon near the top of K.II. of the Bristol sequence. He has also noted examples of Miteheldeania at a higher level—namely, in the Whitehead Limestone, an horizon corresponding probably to the base of C.2. During a recent visit to the Mitcheldean district I collected specimens from the lower shales and also from the Whitehead Limestone, and, thanks to Professor Sibly’s kind directions, I was able to see numerous sections in which he has found this algal development. There can be no doubt that Mitcheldeania is here an important rock-forming organism at least at two horizons in this district, and that it occurs over a considerable area. Interesting as the development of MNtcheldeania in the Forest of Dean undoubtedly is, its real home in Britain is in North Cumberland and along the' Scottish Border, where it flourished to a remarkable extent in the shallow-water lagoons which spread over so large an area in the North of England during early Carboniferous times. Over the greater part of North Cumberland and the east of Roxburgh we find a remarkable development of algal limestones in the formation of which Mitcheldeanva plays a very important part. It is met with especially at two horizons—an upper one, lying immediately below the Fell Sandstone, and a lower one in the middle of the underlying series of limestone and shales. The lower horizon is especially interesting on account of the thick masses of limestone composed almost entirely of algal remains. Though Mitcheldeania forms the basis of this reef-like development, it is accompanied by other algal forms, especially bundles of the minute tubules of Girvanella together with coarser tubes -reminding one of the Spherocodium deposits of Gotland; in places again the marked concentric coatings resemble certain forms of Spongiostroma. The substance of the reef has frequently formed round the remains of Orthoceratites—indeed, the chief layer is usually associated with remains of these Cephalopoda. With other layers occur tubes of Serpulde and remains of Ostracoda. In addition to the limestone of this massive reef, abundant nodules of Miteheldeama lie scattered through the calcareous shales both above and below. 1 GEOL. MAG., Dec. V, Vol. IX, p. 417, 1912: Prof. Garwood—Calcareous Alge. BAY The upper horizon from which Nicholson obtained his type- specimen of If. gregaria at Kershope Foot forms a compact limestone several inches thick. It is made up of small spheroidal nodules about half an inch in diameter, and occurs a short distance below the Fell Sandstone. It can be traced over the whole of North Cumberland and north-west Northumberland from near Rothbury on the east to the Scottish Border at Kershope Foot, and from the headwaters of the Rede in the north to the Shop- ford district in the south. This layer must therefore have been originally deposited over an area of at least 1,000 square miles. The horizon of the upper band is almost certainly that of the C zone of the Bristol sequence.’ It is quite possible, therefore, that it is contemporaneous with the Whitehead Limestone of Mitcheldean. _ This supposition receives support from two other pieces of evidence. In the beds underlying the Ihtcheldeania gregaria band in North Cumberland occur calcareous nodules largely made up of tubes of Serpule—an organism which is completely absent from the West- morland succession, but which is reported by Professor Sibly from the lower limestone shales containing Mitcheldeania in the Forest of Dean district. Again, this upper algal layer in Northumberland and Cumberland is almost immediately overlain by the Fell Sandstone Series, while the Whitehead Limestone at Mitcheldean passes immediately upwards into a sandstone, the Drybrook Sandstone of Professor Sibly, which was originally correlated with the Millstone Grit, but was shown by Dr. Vaughan in 1905 to belong to the Lower Carboniferous Series. It would be interesting if further researches should prove the existence of a former gulf at the end of Tournaisian times, running from the Forest of Dean to the east of North Wales, through North Cumberland to the southern slopes of the Cheviot Isle, with a branch given off eastward into Westmorland. In any case it is a remarkable fact that we have a great development of algal deposits at this period in Gloucestershire, Westmorland, Lancashire, North Cumberland, and Northumberland. Ortonella.—Vhis form, as already mentioned, occurs in great abundance in the algal band in the ‘ Athyris glabristria zone’ of the North-West Province. It is found in spherical nodules up to the size of a small orange. In microscopic sections it resembles Mitcheldeania in so far as it consists of a series of tubes growing out radially from a centre. It differs, however, from this genus in many important respects. All the tubes are approximately of the same size, and there is no evidence of alternating coarse and fine tufts arranged concentrically, as in the case of Mitcheldeania. Further, the tubes are not undulating as in that genus, and therefore in thin slices lie for a long distance in the plane of the section. They are much more widely spaced and show marked dichotomous branching, the bitur- cations making a nearly constant angle of about 40°, and there is a strong tendency for the branching to take place in several tubes at about the same distance from the centre of growth, producing a general concentric effect in the nodule. 1 Geology in the Field, pt. iv, p. 683, and Q.J.G.S., vol. Ixviii, p. 547, 912. 548 Prof. Garwood—Caleareous Alge. The diameter of the tubes is decidedly less than those in Mitchel- deania, being usually little more than half the size of the larger tubes of IL. gregaria. The nodules of this genus occur in great profusion, contributing largely to the formation of the shaly dolomite at the base of the ‘ P. globosus band’ throughout the Shap, Ravenstonedale, and Arnside districts in Westmorland and Lancashire. In addition to these genera there occur also two other encrusting calcareous growths which require mention. The first of these appears in thin sections in the form of a ‘festoon-like’ growth, surrounding fragments of Caleareous Algee, especially Mitcheldeaniva and Ortonella. I have met with it abundantly in the ‘ Algal band’ in the north-west of England, but it also occurs not infrequently associated with Jhtcheldeania in the Whitehead Limestone in the Forest of Dean, while a similar structure occurs associated with Mitcheldeania gregaria in North Cumberland. The other deposit is the form already alluded to under the term Spherocodium, which I have found forming considerable masses of rock in many districts where the Lower Carboniferous beds are exposed, not only in Westmorland and North Cumberland, but also in the Bristol district, the Forest of Dean, and South Wales. Foreign Carboniferous. From its general similarity to the British deposits we might expect to find examples of an algal development in some portion of the Belgian , Lower Carboniferous succession. As already mentioned, large masses of encrusting calcareous deposits have been described by Girich’ from the Visean Limestones of the Namur Basin as Spongrostroma, ete., which, though referred by him to the Rhizopoda, may very well be calcareous precipitates deposited by algal influence. Many of these deposits are similar to those mentioned above from British rocks. No undoubted remains of Calcareous Algz have, however, yet been recorded from these Belgian rocks. It may be of interest, therefore, to mention the recent discovery by Professor Kaisin, of Louvain, of certain algal remains in the beds overlying the Psammites-de- Condroz at Feluy on the Samme. The form found here resembles Ortonella of the Westmorland rocks, but the tubes are much finer, and it may turn out to represent a species of Dhitcheldeania. During a recent visit to Belgium I had the pleasure of visiting the Comblain- au-Pont Beds, in the Feluy section with Professor Kaisin, and, although these beds have been previously classed as Devonian, I agree with him that they probably belong to the base of the Carboniferous and correspond approximately to K of the Bristol sequence. In the company of Professor Dorlodot and Dr. Salée, I also visited the chief sections of the Visean, and we succeeded in discovering at least three horizons at which nodular concretionary structures, probably referable to algal growths, occurred. In 1908 Schubert (Jahrb. d. k. k. geol. Reichsanstalt, 1908, Bd. 58, Hit. 2, pp. 347, 382, pl. xvi, figs. 8-12) published descriptions of two new forms of the Siphonee—Jfzz:a and Stolleyella—trom the ' Mém. du Musée Roy. d’Hist. Nat. de Belgique, t. iii, 1906. Prof. Garwood—Caleareous Alga. 549 Fusulina Limestone of the Velebit district in Dalmatia, while later, in 1912 (Verh. d. k. k. geol. Reichsanstalt, 1912, p. 330), he records further examples of these genera from specimens, collected by Koch, of rocks of the same age in Croatia. The same genera have also been recorded by Karpinsky from the Fusulina Limestone of Japan (Verh. d. Russ.-kais. Min. Gesell. St. Petersb., ser. 1, Bd. 46, 1908, p. 257, pl.ii1). Still more recently another form of Girvanella has been described by Yabe from the (?) Carboniferous rocks of San-yu-tung and other localities in China under the name of G. snensis.! Permian anp TrIAs. In Britain I have met with no reference to the presence of Caleareous Alge in rocks of this period, but quite recently Mr. Cunnington, of H.M. Geological Survey, sent me a few nodules from the base of the Permian near Maxstoke; in thin sections they resemble very closely specimens of Spongiostroma from the Carboni- -ferous Limestone described above. On the Continent masses of limestone, composed almost entirely of remains of Diplopora and Gyroporella, have long been known trom the Muschelkalk and Lower Keuper beds of the Kastern Alps, notably the Mendola Dolomite, the Wetten Limestone of Bavaria, and from similar horizons in Tyrolian Alps. In the Lombard Alps the same facies reappears, and Diplopora annulata occurs abundantly in the well-known Hsino Limestone above Varenna, while recent work by Cayeux(C. R. Acad. Sci., Paris, tome clvui, p. 272, 1911, and Exploration Arch. de Délos, Paris, vol. iv, pt. i, 1911), Négris (C. R. Acad. Sci., Paris, tome eclv, p. 371, 1912), and Renz (Centralb. f. Min., 1911, pp. 255, 289, and ibid., 1912, p. 67; also Jahrb. Osterr. geol. R. A., lx, pt. ii, p. 451, 1910) on the Triassic rocks of the mainland of Greece and the Cyclades shows the wide distribution of the Algal limestones in the south and south-east of Europe. In 1891 Rothpletz* showed that certain spherical bodies in the Triassic beds of St. Cassian, formerly regarded as oolitic structures, were in reality algal growths, and referred them to a new genus, Spherocodium, on account of their apparent resemblance to the living form Codium. He describes them as encrusting organisms forming nodules up to several centimetres in diameter. They contribute substantially to the rocks in which they occur, and are found especially in the Raiblkalk, the Kossenerkalk, and the Plattenkalk. JURASSIC. The Mesozoic rocks of Britain contain but few examples of marine algal limestones, and important occurrences are confined to the Jurassic rocks. The forms met with are limited to two genera, Gurvanella and Solenopora. Tubes of Gorvanella occur fairly abundantly in the British Oolites, especially in the well-known Leckhampton Pisolites, and Mr. Wethered, who has made a special study of oolitic structures, appears inclined to refer all oolitic structures to organic agency of this nature. 1H. Yabe, Science Reports of the Tahoku Imp. Uniy., ser. 11, Geology, vol. i, No. 1, Japan, 1912. 2 Zeitsch. d. deut. Geol. Ges., vol. xliii, pp. 295-322, pls. xv—xvii, 1891. \ 550 Prof. Garwood—Calcareous Alge. The examples of Solenopora met with in the Great Oolite’ and Coral Rag are of special interest. In both cases they attain very much larger dimensions than any species yet discovered in the Paleozoic rocks. At Chedworth, near Cirencester, I have collected masses of Soleno- pora jurassica, measuring up to a foot across, in which the original pink tint is still so conspicuous on freshly fractured surfaces as to give rise to the local appellation of ‘ Beetroot Stone’, and the colour also reminds one of the red alge growing in great profusion at the present day in the Gulf of Naples. It is also recorded from the same horizon by Dr. Brown? from near Malton in Yorkshire, and also, on the authority of the late Mr. Fox Strangways, by Rothpletz.’ In Yorkshire, however, one form undoubtedly occurs at a higher horizon, namely, in the Coral Rag of the Scarborough district, where it is well known to local collectors. Specimens which I have collected from this horizon at Yedmandale and Seamer also attain a considerable size—up to 3 inches in their longest dimension. The name Solenopora jurassica was given by Nicholson in manuscript to specimens from Chedworth, and was adopted by Dr. Brown in his description of the specimens from both Chedworth and Malton in Nicholson’s collection. Rothpletz points out that specimens examined by him from York- shire differ from the genotype in the fact that the cells are typically rounded in cross-section and by the absence of perforations in the cell-walls, and he therefore proposes to separate it as a new genus Solenoporella. It seems probable that some confusion has arisen between the specimens to which Nicholson originally gave the name of S. jurassica from the Great Oolite of Chedworth and other specimens from Malton from a higher horizon*—the Coral Rag. I have collected specimens from both horizons and consider that the Chedworth specimens, to which the name Solenopora jurassica was originally given, represent a species of true Solenopora, showing closely packed cells with polygonal outline in tangential section; the form from the Coral Rag of Yorkshire, with distinct circular outline to the tubes in tangential section, is specifically, if not generically distinct, and is that described by Rothpletz as Solenoporella. If this view be correct we should continue to speak of the specimens from the Great Oolite at Chedworth as Solenopora jurassica, while those from the Coral Rag of Yorkshire must be known as Solenoporella sp., Rothpletz. ' Foreign Jurasste. In foreign Jurassic rocks the recorded occurrences of Calcareous Algee are surprisingly few. Quite recently, however, Mr. H. Yabe® has described a new species of Solenopora, under the title IMetasolenopora Rothpletzt, from the 1 Proc. Cot. Nat. Club, vol. x, p. 89, 1890. Grou. MaG., Dec. IV, Vol. I, pp. 145 et seqq., 1894. Kungl. Svenska Vet. Akad. Handl., Bd. xliii, No. 5, 1908. 4 See Fox Strangways, Grou. MaG., Dec. IV, Vol. I, p. 236, 1894. Sci. Rep. Tahoku Imp. Univ. Japan, 1912. ww uo Prof. Garwood—Caleareows Alge. ; 551 Torinosu Limestone, Japan. This discovery is of interest, as it carries the known occurrence of Solenopora up to the base of the Cretaceous, in which formation Lithothamnion appears and thenceforward becomes the chief representative of the rock-building Coralline Alge. CRETACEOUS. We here reach the period when Lithothamnion and its allies begin to make their appearance. They have not yet been recognized in British rocks, but are widely distributed in deposits on the Continent. They occur in the Cenomanian of France, in the Sarthe and the Var, but especially in the Danian of Petersburg, near Maestricht. Other forms which may be mentioned are Diplopora and Triplo- porella. The former is met with abundantly in the Lower Schratten- kalk in certain districts, especially Wildkirchli, where it plays a considerable part in the formation of the deposit.’ TERTIARY. In Britain no example of marine Calcareous Alge have, so far as I am aware, yet been reported, but considerable deposits of freshwater limestone, rich in remains of Chara,” have for long been known from the Oligocene of the Isle of Wight. Foreign Tertiary. On the Continent, however, thick deposits rich in Zzthothamnion and Lithophyllum have been known for many years. Of these I may mention especially the well-known Leithakalk of the Vienna Basin and Moravia. It will be remembered that it was these deposits which formed the subject of Unger’s important monograph in 1858. ConcLusions. The facts given above regarding the geological distribution and mode of occurrence of these organisms lead us to several interesting conclusions. In the first place there can be no doubt from the examples described above that they play a very striking part as rock- builders at many different horizons in the geological series. At the same time it is evident that not only are certain forms restricted to definite geological periods but also that they had a wide geographical range, and on this account these organisms will often be found valuable as zonal indices either alone or in conjunction with various other organisms. As an example of this wide distribution we may cite Solenopora compacta, which flourished so abundantly during Llandeilo—Caradoc times not only in the Baltic area and Scotland but also in England, Wales, and Canada; again, the wonderfully persistent development of the Rhabdoporella facies over the whole of the Baltic area at the close of Ordovician times was of so marked a character that even boulders of these rocks scattered over the North German plain can be made use of in tracing the direction. of flow of the ice-sheet during Glacial times. 1 Arbenz. Vierteljahrsschr. Naturf. Ges. Zurich, vol. liii, pp. 387-92, 1908. 2 This form, though till lately included.among the green alge, is now usually placed in a distinct group—the Charophyta. > Denksch. k. Akad. Wiss. Miinchen, vol. xiv, p. 18, 1858. 552 Prof. Garwood—Calcareous Alge. To take examples nearer home. The ‘ Ortonella Band’ found throughout Westmorland and North Lancashire near the summit of the Tournaisian occurs so constantly at the same horizon as to constitute one of the most valuable zonal indices in the succession in the North-West Province, and can not only be used with the greatest confidence for correlating widely separated exposures, but it has also afforded valuable evidence of tectonic disturbances. Other examples are supplied by the ‘ Girvanella Nodular Band’ at the base of the Upper Dibunophyllum Zone, and the IMitcheldeania gregaria beds in the North of England and in the Forest of Dean. Again, the presence of these organisms at particular horizons furnish us with interesting evidence as to the conditions which obtained during the accumulation of the deposits in which they occur. At the present day Calecareous Algz flourish best in clear but shallow water in bays and sheltered lagoons. As a good example we may take the Algal banks in the Bay of Naples, described by Professor Walther,’ where Zithothamnion and Lithophyllum flourish to a depth of from 50 to 70 metres. There is seldom any muddy sediment on these banks, though detrital limestone fragments are widely distributed. Another interesting point is the constant association of fossil Calcareous Alge with oolitic structure and also with dolomite. Thus oolites occur in connexion with Solenopora in the Lower Cambrian of the Antarctic, in the Craighead Limestone at Tramitchell, in the Ordovician rocks of Christiania and the Silurian of Gotland, and in the Lower Carboniferous Limestone of Shap; while in the Jurassic rocks of Gloucestershire and Yorkshire this genus occurs associated with the most typical oolitic development to be met with in the whole geological succession. Though Mr. Wethered has made out a good ease for the constant association of Grrvanella tubes with oolitic grains there are many cases in which this association cannot be traced. M. Cayeux*?in writing of a mass of Girvanella from the ferruginous oolites of the Silurian rocks of La Ferriére-aux-Etangs expresses his opinion that Girvanell/a encrusts the oolite grains but does not form them, and that it is really a perforating alga of a parasitic nature. The presence of dolomites in connexion with algal growths at different geological horizons appears to show that the beds have accumulated under definite physiographical conditions similar to those which obtain to-day in the neighbourhood of coral reefs. ° Such lagoon conditions would tend to come into existence during periods — of subsidence or elevation, and this is just what we find when we examine the periods at which these reefs are most persistent. Thus the Girvan Ordovician lagoon-phase occurred duringan elevation which culminated with the deposition of the Benan Conglomerate ; the Lower Carboniferous ‘Algal band’ in Westmorland was laid down during the subsidence which followed the Old Red Sandstone continental period, while the Upper Girvanella Nodular band occurred 1 Zeitsch. deut. Geol. Ges., 1885, p. 229. Abh. Konig]. Preuss. Akad. Wiss., 1910. 2 Comptes Rendus Acad. de Sci. 150, 1910, p. 359. i Nie ee ‘ pete chk ae poe Ruri uA 2 FORMATIONS. Newer Tertiary . Miocene Oligocene Eocene. Cretaceous . 3 Jurassic ‘ Purbeck. Coral Rag. Great Oolite. Trias Permian Carboniferous— Upper & Lower . Base of Upper Dibunophyllum zone. Athyris gla- bristria zone. Devonian Silurian— Ludlow. Wenlock. Ordovician— Upper Caradoc. Ardmillan Series (Whitehouse Group). Llandeilo- Caradoc (Stinchar and Craighead Limestone). Cambrian BRITISH LOCALITIES. ? Solenoporella Yedmandale, Seamer Ruston, etc., Malton. Solenopora jurassica Chedworth, near ? Spongiostroma Girvanella a fs Ortonella . Solenopora Gar- woodi Mitcheldeania gre- garia, Mitcheldean Whitehead Group M, Nicholsoni, Mit- cheldean, Lower Limestone Shales ? Spongiostroma ? Girvanella Girvanella proble- matica (?) Solenopora litho- thamnioides Girvanella proble- matica Solenopora com- pacta, var. Peachit, S. fusiformis, S. filiformis Cirencester. Maxstoke, near Coventry. Coldstream, Penygent Humphrey Hd., ete. Tortworth, Clifton Shap, Orton, Raven stonedale, Meathop etc. Shap Abbey, Stone Gill Meathop, Clifton. Scottish Border, Cum berland, Northum berland. Scottish Border and Cumberland. Widely distributed at several horizons especially at Orton. Hope’s Nose Lime stone. Mayhill, Malvern, etc Shalloch Mill, Girvan Girvan district. Girvan district; Hoaj Edge, Shropshire Yat Hill, shire, and ithotham- vion: North spas a Hrvanella ? Mitchel- deania. Radnor Fas, ANTARCTIC, Solenopora PSE Ih mE: J. Reid Moir—Sub-crag Flints. 553 when the marine period of the Lower Carboniferous was drawing to a close and a general elevation was taking place. Similar conclusions could be drawn from the Gotlandian and other periods recorded above. In conclusion I venture to express the hope that however incomplete the account of the succession of forms which I have given may be, it may nevertheless help to stimulate an interest in these rock-building Algee and encourage geological workers in this country to turn their attention toa hitherto neglected group of forms of great strati- graphical importance. In the accompanying Table II are set out the more important Algal horizons so far described in the Paleozoic and Mesozoic rocks, together with a few typical occurrences of Tertiary age, but the table makes no claim to be exhaustive, as additional evidence of the importance of these organisms is constantly coming to hand; thus since the publication of the last number of this Magazine I have received from Professor Rothpletz' a description of a new form of Spherocodium, S. s¢mmermanni, which he finds playing an important part in the ‘so-called conglomerate’ in calcareous sandstone near Liebichan Silesia, formerly classed as Culm, but which has recently been shown by Zimmermann to be of Upper Devonian age. V.—Tue Sus-crac Frits. By J. Rem Morr, F.G.S8. T the meeting of the British Association held at Birmingham last September, Professor W. J. Sollas, F.R.S., read a paper in which the Sub-crag flints I have discovered were rejected as not being of human workmanship. Professor Sollas mainly based his arguments upon certain flints found upon the seashore at Selsey Bill, Sussex, many of which have been collected by Mr. E. Heron Allen of that place. In August of this year I paid a visit to Selsey and, owing to the kindness of Mr. Heron Allen, was enabled to carefully examine his colleetion of flints and the exact places on the shore from which they were derived. The conclusions I arrived at regarding these specimens and their method of fracture are as follows :—, An examination of the flints in Mr. Heron Allen’s collection from | the surface of the Eocene clay at Selsey Bill clearly shows that they differ widely both in mineral condition and ‘ patination’, and do not belong to one geological period. When each series is arranged apart the specimens are seen to resemble very closely those found in East Anglia (1) below the Red Crag, (2) in the Middle Glacial Gravel, and (3) in the Chalky Boulder-clay. The occurrence of flints of these three series at one horizon in the South of England is of some interest and importance, and seems to indicate the breaking up of these deposits and subsequent deposition of their material at the spot where they are now found. The specimens 1“ Uber Spherocodium Zimmermanni aus dem Oberdeyon Schlesiens ”’ : Jahrb. d. k. Preuss. Geol. Landesanstalt, 1911, Bd. xxxii, T.1i, Hft. i, p. 112, pls. 4, 5. Jurassic =» «| Purbeck. Corn) Hag. Great Oolite. Trias. . . Permian. Carboniferous Upper & Lower ieee na Ran Athurts gla- bristria sone, 2 Solenoporella Yedmandale, Seamer, | Ruston, etc., and | | Malton. | Solenopora jurassica Chedworth, near Cirencester. Maxstoke, near ? Spongiostroma Coventry. Coldstream, Penygent. Humphrey Hd., ete., Tortworth, Clifton. Girvancla F Ortonlla., . . Shap, Orton, Raven- stonedale, Meathop, to, Soler Gar- ha AbbersBioas Gil’ i eathop, Clifton, Mitcheldeania gre- Scottish Border, Cum- aria, Miteheldean berland, Northum- hitehead Grou berland, . Nie , Mit- Scottish Border and cheldean, Lower Cumberland. Limestone Shales ?Spongiostroma . bn distributed at horizons. Sxoedially at Orton, "s Nose Lime. ?Girvanedla . . Ho stone. Batic Provinces. | N : | Spongiostroma, Spherocodium got- landicum, Soleno- pora gotlandica: tland. ORTH AMERICA. | MIDDLE EUROPE. oe * ~ Lithothamnion: Val gana. Lithothamnion: = Ariege. Dactylopora: Paris (Calcaire Grossier). {Danian &Senonian] D plopora, Triplopo- Lithothamnion: Maestricht, Mar- Vildkirehli seilles; Pisolitic Limestone, Paris. == plopora | Diplopora: D Alsace-Lorraine Spherocodiwm: (Muschelkalk). yrol (Wengen St. Cassian, etce.). te.: Lombardy sino Limestone). Mizzia, Stolleyella : elebit, Dalmatia, nd Croatia. Spongiostroma . = Visean of Namur. Lowest Ortonella or fat Mitcheldeania at Veluy. U. Devonian, Silesia :| Sycidiwm? Eifel. Spherocodium Zimmermanni. ella: Schrattenkalk, | lopora, Gyroporella, Diplopora,Gyroporella, GwWroporella: 8. Tyrol. Leithakalk, with Litho- hamnion, Vienna asin and Moravia. | | SovuTH EUROPE. - Lithotham- NION}; Girgenti. Lithotham- nton: Alhama, ete., Spain. Diplopora, Gyroporella: Greece, main- land, and Cyclades. ASIA, Lithotham- nton: Lake Wan, Armenia. Lithotham- ntorn: Trebizond, ete., Armenia. Turonian— | Tritplo- porella: Lebanon. *Cale-Alge’: Lake Urmi, Armenia, ke: AND ey Lithotham- nton? Philippines, Metasoleno- pora: Japan (Torinosu Limestone), Mizzia, Stolleyella: Akasaka, Mingo, Japan, Girvanedla sinensis: Carboniferous? Japan, AND « MADAGASCAR, Lithotham- nition: North Madagasear, Girvandla ? Milchel- re ANTARCTIC, es ie bee 554 J. Reid Moir—Sub-crag Flints. have naturally had a lot of rough usage while being transported from one site to the other and have also suffered considerable disintegration, as is clear from the cracked condition of the lumps. Prolonged examination of the East Anglian flints from the three horizons mentioned has shown that those below the Red Crag are hard and sound, while those from the Middle Glacial Gravel and Chalky Boulder-clay are much more easily cracked and broken up. It is therefore very interesting to find that the same rule holds good at Selsey, where specimens, apparently of the same age as the Sub-crag samples of East Anglia, are not so much broken as those which appear to have come from Middle Glacial and Chalky Boulder- clay deposits. The ‘Sub-crag’ specimens from Selsey are in some cases humanly flaked, and the flaking is in every way the same as that seen upon the East Anglian flints. The flakes are large and have been removed by blows of considerable force delivered in a vertical direction and resulting in smooth, clean surfaces, generally free from conchoidal rippling. Fissures or small ‘splits’, radiating from the point of impact, are very often developed upon the surface of the flakes, which frequently required repeated blows to detach them from the block. The flints also exhibit a dark rich brown colour, and in many cases well-marked ‘ weathered-out’ scratches. These peculiarities are to be seen upon the Kast Anglian Sub-crag specimens, and moreover the forms of worked flints from the two sites are almost exactly similar. (Mr. Heron Allen tells me that the smaller Sub-crag types such as borers, scrapers, etc., have not been found at Selsey.) Out of the large series of Selsey flints about twelve have been definitely worked by man, and only four of these were undamaged and in a good state of preservation. These were all of a Sub-crag type; some of the others may at one time have exhibited human work, but if so, subsequent natural fracturing has effectually disguised it. In order to demonstrate that the flints with cracks running through their mass could easily be disintegrated, I dropped one upon a tougher specimen, and, as I expected, the impact was sufficient to shatter it in pieces. Some of these fragments, which of course bore no real resemblance to man’s work, were of a somewhat suggestive shape, and if subjected to some amount of rolling by the sea might very well deceive an unpractised eye. A visit to the exposure of these flints on the foreshore confirmed the belief that the sea is at the present day breaking up the blocks, and a single tap of the hammer is often enough to reduce them to fragments. It is clear that the large majority of the Selsey specimens have been fractured in the manner I describe, and a comparison of the fractured surfaces with those produced by my experiment shows an exact agreement. There is the same dull, lustreless appearance, the same uneven ‘hackly’ fracture, and the same indisputable evidence that the flint has broken along the lines of least resistance. There is also no sort of resemblance in these fractures to those on the other specimens which have been produced by heavy well-directed human blows. F. Chapman—Eocene Foraminifera. : 555 The fact that the Selsey specimens are found upon the present sea- shore has induced some observers to assert that all the fractures have been caused by wave-action on the shore, and that it is possible to observe the process actually going on. The latter fact is not denied, and indeed has been tested by experiment, but the fractures so produced are quite distinct from those attributed to human agency. It is also quite clear that wave-action on the present beach has simply removed typical ‘natural’ flakes, that is those which have been caused by blows falling on an edge instead of at the side of it, the former showing prominent ripple-marks owing to the blows being oblique instead of vertical. These ‘natural’ flakes are never very large, and often cut deeply into the flint, developing into a ‘step’ at the end opposite to the point of impact. The alleged discovery of a rostro-carinate ‘implement’ fixed in the Eocene clay and in process of manufacture must, I think, be received with very great caution, especially as it appears that the ventral plane, from which the flakes are generally removed to form the carina, was turned towards the shore, and therefore not exposed to the hypo- thetical battering of the stones br ought in by the sea. The small series of flints collected by Mr. Heron Milles shows a fundamental difference, which is best explained by the difference known to exist Reemced human and natural flaking, the presumed implements being picked out with ease from others which are obviously formed by natural agencies. Moreover, there appear to be no transitional forms, the two series being sharply enough defined for those familiar with the fracture of flint. The ‘human’ series examined on this occasion contains no typical rostro-carinate implements, and the superficial resemblance of others to that type will not bear investigation. VI.—Own some ForAMINIFERA FROM THE EocEeNE BeEps oF Henertstpury Heap, HampsHire. By FREDERICK CHAPMAN, A.L.S., F.R.M.S., Palzontologist to the National Museum, Melbourne. N the March Number of this Magazine Mr. Cowper Reed recorded the interesting discovery of a series of fossils which points to a Bartonian horizon for the Hengistbury ironstone. Upon reading this paper I was reminded of some chocolate-coloured clays with Foraminifera which I had collected from a seam between the ironstone bands at Hengistbury Head in August, 1895. The washings from these clays afforded abundant tests of arenaceous forms; and since, so far as I am aware, no Foraminifera have yet been recorded from this locality, it may be of some interest to publish the results of an examination of the material collected. From my notebook I find this sample, chocolate-coloured sandy clay with glauconite, was collected between the two ironstone bands on the west side of Hengistbury Head. No direct evidence could be gathered from the present series as to relationship with the Fora- minifera of the Barton or Bracklesham Beds, from both of which 556 Ff. Chapman—Eocene Foraminifera. formations I had collected on an extensive scale. The tests are all arenaceous, the facies representing a somewhat different hydrographic condition from that of the deposits belonging to the two last-named series, represented in my collection from the Barton Cliffs, Brackles- ham Bay, and from many typical exposures in the Isle of Wight. DescriPTION OF THE FoRAMINIFERA. Fam. LITUOLIDA. Genus HaprtopHracmium, Reuss. Haplophragmium canariense, VOrbigny, var. pauperata, nov. Figs. 1-4. This variety is distinguished from the specific type’ by its small and distorted condition, often accompanied by a deflation of the finely arenaceous walls of the chambers. The more regular examples, of which there are one or two exceptional cases, link themselves with H. canariense, of cosmopolitan distribution. The variety is smaller than type-specimens of the species, the former averaging ‘58 mm. in greatest diameter, whilst the latter measures *84 mm. ( Challenger example). H. canariense, var. pauperata is moderately abundant in the washings from the clay seams of Hengistbury Head. Genus Lirvota, Lamarck. Lituola simplex, Chapman. Figs. 7, 8. Lituola simplex, Chapman, 1904, Ree. Geol. Surv. Vict., vol. i, pt. iii, p. 228, pl. xxii. Several sub-discoid and crosier-shaped tests, very thin and com- pressed, and consequently very fragile, were found in the washings. They can be distinguished from mere adventitious flakes or con- eretions of mud by their simulation of the depauperated and compressed forms of Haplophragmium and Trochammina. Their obscurely septate and labyrinthic internal structures make them come within the Lituolid group. The original examples above quoted were from similar washings of chocolate-coloured clays from the Miocene (Janjukian) of Brown’s Creek, Otway Coast, Victoria. This particular fauna was remarkable for its shallow-water and estuarine character, although, strange to say, the genus Cyclammina, more or less depauperated, was also abundant therein. This latter genus was only recorded between 100 and 2,900 fathoms by the Challenger, and was then (in 1884) ‘‘unknown in the fossil state”. Subsequently, however, Cyclammina has been noted from moderately shallow-water fossil deposits from the ? Jurassic onwards.” The average diameter of the tests of Z. simplex, as occurring in the present washings, is*65mm. The diameter of that figured from the Victorian Miocene is ‘55 mm. 1 Nonionina canariense, d’Orbigny, 1839, Foram. Canaries, p. 128, pl. ii, figs. 33, 34; Haplophragmium canariense, d’Orb., sp., Brady, 1884, Rep. Chall., vol. ix, p. 310, pl. xxxv, figs. 1-5. 2 Rec. Geol. Surv. Vict., vol. i, pt. iii, p. 229, 1904. F. Chapman—Eocene Foraminifera. B57 Genus Trocuammina, Parker & Jones. Trochammina inflata, Montagu, sp., var. macrescens, H. B. Brady. Figs. 5, 6. Trochammina inflata, Montagu, sp., var. macrescens, Brady, 1870, Ann. Mag. Nat. Hist., ser. Iv, vol. vi, p. 290, pl. xi, figs. 5a-c. This variety is even more emphasized in its emaciated condition than the specimens figured by Dr. Brady from tidal river deposits of the River Blythe, Northumberland, and the River Wear, 2 miles above Sunderland, although some examples from Hengistbury Head match it almost exactly excepting in the less open umbilicus. In the recent and brackish mud deposits, as pointed out by Brady, the tests seem to show that the emaciated appearance is due to the falling in of the thin, chitinous, and sparsely arenaceous walls, from the contraction of the protoplasm i in drying. The specific form 7. inflata is usually found in moderately shallow marine to brackish waters round the British coast. FORAMINIFERA FROM THE EOCENE OF HENGISTBURY HEAD, HAMPSHIRE. x 25. Drawn by F. Chapman from nature. Fics. 1. Haplophragmiwm canar iense, d’Orb., sp. var. pauper ata, nov. Dorso- lateral aspect. H. canariense, d’Orb., sp., var. pawperata, nov. Oral aspect. Ki a 3 x 4 Lateral aspect. sb Micromorphic. Trochammina mflata, "Montagu, 'sp., var. macrescens, Brady. Lateral aspect. 5d, oral aspect. ‘ T. mflata, Montagu, sp., var. macrescens, Brady. Smaller example, lateral aspect. Lituola simplex, Chapman. Lateral aspect. a Another example, lateral aspect. Vr gulina subsquamosa, Egger. Lateral aspect. ODI PD NRW BBBr vt F. Chapman—Eocene Foraminifera. The largest example of the Hengistbury Head series has a diameter of -6mm., whilst the larger of Dr. Brady’s figured examples from the English tidal rivers has a diameter of 4mm. This variety is exceedingly common in the washings. Fam. TEXTULARIDA. Genus Virevtina, d’Orbigny. Virgulina subsquamosa, Egger. Fig. 9. Virgulina subsquamosa, Egger, 1857, Neues Jahrb. fiir Min., etc., p. 295, pl. xii, figs. 19-21; Brady, 1884, Rep. Chall., vol. ix, p. 415, pl. ii, figs. 7-11. ‘ Foraminiferal tests allied to this form have already occurred in the estuarine deposits (Holocene) of the Fen-land in the East of England. Only one small example of this species was found, having a length of -423 mm. Note on the accompanying Ironstone Bed.—A thin slice of the iron- stone of the Hengistbury Head Beds was examined under the microscope, with the following result :— The general character is that of a fine-grained ironstone composed of excessively minute granules of carbonate of iron stained with peroxide of iron. Scattered throughout the rock and occasionally occurring in nests are minute angular fragments of quartz, such as are met with in the finest river silts. A few obscure stem-like fragments are also seen embedded. Under a high power the separate granules of carbonate of iron are seen to be covered with peculiar amber and ruddy-coloured articulations, probably representing the residual peroxide of iron after the change from the condition of bog- iron ore. Conditions of Deposition.—Some interesting facts are brought out by the foregoing occurrence of the somewhat sparse and peculiar foraminiferal fauna of the Hengistbury Head clays. The forms are all arenaceous, showing a marked absence of calcareous rocks or calciferous waters in the neighbourhood. Such a fauna is generally found in the tidal estuarine areas of great rivers close to the coast and having a partially landlocked character. Similar deposits would occur, for example, on those parts of the Essex Flats at the present day, which are occasionally flooded at especially high tides, and where, in the boggy parts, saprophytic vegetation flourishes, capable of extracting the carbonate of iron from the surrounding water. The small dimensions of these Foraminifera, the poorly developed tests with shrunken chambers, and generally starved appearance point to their being a survival of a normal deep-water terrigenous facies, which has been pushed into uncongenial surroundings; for parallel types of all the forms here enumerated are well known in many of the green and blue muds of our deeper coastal deposits. The question here arises, how came the glauconite grains in the clay deposit if the evidence of the Foraminifera points so strongly to estuarine conditions? for glauconite seems to be, so far as known, a material which is chemically deposited under marine conditions in 1 Brady, loc. cit., p. 415. Dr. F. Oswald—Trias and Carboniferous, Caucasus. 559 moderately deep, not shallow water, and generally below the actual mud-line of the coastal margin. From geological evidence derived from other sources it is quite reasonable to assume that these glauconite grains in the clays, which by the way are worn and otherwise ill-defined, have been derived from local, disintegrated and re-sorted, moderately deep-water deposits, such as are seen in the Barton and Bracklesham Beds themselves. In the Plateau Gravels of the London Basin, by way of illustration, glauconite grains are frequent; but no one would venture to assert that these granules were actually formed in the deposit, since much of the material in places was derived from the Lower Greensand ridges to the south. The difficulty of accounting for the presence of mollusca and sharks’ teeth in the closely associated sediments may be met in this way. A slight lowering of the estuarine series would convert the area into sandy and clayey submerged marine coastal plains, on which such genera as Corbula, Tellina, Leda, Arca, Glycimeris, Anomia, Cardium, and Cardita could flourish; whilst slightly deeper conditions would permit of the existence of genera like Panopea. At the same time the fact of many of the mollusca found in this series being in the state of casts, shows that the sea-bottom at this period was in a state of oscillation rather than of equilibrium. NOTICHS OF MEMOTRS.- OPS VEN Trias AND CARBONIFEROUS IN THE CAUCASUS. Wirrensure, P. W. Recent Researches on the Trias of the Caucasus. (In Russian.) Bull. Acad. Imp. Sci. St. Petersburg, 1912, p-. 433. -Rosinson, W. N. Recent Researches on the Geological Structure of the Northern Caucasus in the Basins of the Rivers Bielaya and Laba. (In Russian.) Bull. Acad. Imp. Sci. St. Petersburg, 1918, p. 33. Translated and abridged from the Russian by Frrrx Oswatp, D.Sc., F.G.S. f|\HE discovery in 1907 of Upper Trias in the Kuban district of the | - Caucasus, which was described in the GrotocicaL Macazine (Dee. V, Vol. VI, No: 538, April, 1909, p. 171), has been con- siderably amplified and extended by the researches of P. W. Wittenburg, who explored the same district, viz. the upper courses of the Little Laba and Bielaya Rivers, and his results may be con- veniently summarized in tabular form :— 1. Rhetie Stage—(1) Typical Avicula contorta beds on Mt. Tkhach. (2) Lower Rhetic is represented by grey crinoidal lmestone interbedded with red marly limestone containing many Brachiopods, particularly masses of Sporigera belonging to the typically Rhetic group of S. oxycolpos, Emmr., and S. Manzavinii, Bittn. (Kossen Beds). It is well exposed in the Kun Valley near Mt. Tkhach, and 560 Notices of Memoirs—Dr. Felix Oswald contains Waldheimia cubanica, Tschern., W. cf. austriaca, Zugm., W. Bukowski, Bittn., Terebratula pyriformis, Suess, T. turcica, Bittn., Ehynchonella obtusifrons, Suess, Spirigera cubanica, Tschern., Retsia superbescens, Bittn., Amphiclina squamula, Bittn., Aulacothyris cf. Loharensis, Bittn., Mysidioptera Gremblichi, Bittn., Pecten subalterni- costatus, Bittn. . 2. Norte Stage-—The facies of the Dachstein Limestone with Megalodus sp. of the group Degalodus (Neomegalodon) triqueter, Wulfen, was found on Mt. Yatyrgvart (also in the Kuban district), but this seemed to be a somewhat isolated occurrence. The red, compact limestones usually contain a rich coral fauna (not specified) with masses of Pseudomonotis ochotica, var. densistriata, Teller, which the author considers to be synonymous with Ps. (onotis) salinaria, Bronn. They dip 10° N.W. by N. and are transgressive over 38. 3. Carnie Stage.—Black, thinly-bedded, micaceous slates, inter- bedded with grey sandstones, altogether about 75 metres thick. They contain Koninckina Telleri, Bittn., and badly preserved Zropites. In the lower horizon of this series, on the eastern slopes of Mt. Tkhach, thick beds of oysters occur. 4. Ladinian.—(1) Red, quartzitic sandstones, interbedded with. black slates and marls, dipping 20° N.N.W., containing the charac- teristic Wengen fossils Daonella Lommeli, Wissm., and Posidonomya wengensis, Wissm., with siliceous sponges and plant-remains in the upper part. The best sections occurred in the Sokhra Valley. (2) Conglomerate. (8) ‘Upper contorted series,’ consisting of grey calcareous flag- stones, well developed to the south-east of Mt. Tkhach, and containing a Cephalopod fauna (described by Professor Karl Diener). Owing to their poor preservation the fossils could only be generically determined as follows: ‘‘ Péychites sp ind. of the J/egalodiscus group ; gen. ind. sp. ind. of the Pinacoceratide family, recalling Worites or. Arthaberites, but the condition of the suture-lines would permit of its being included in Sageceras; Gymnites sp. ind. aff. tncultus, Beyr. ; Monophyllites sp. ind. of the group If. Suessi, Mojs., closely resembling J/. Pitamaha, Diener; Donophyllites n.sp.; gen. ind. sp. ind. of the Ceratitide family, recalling Celtites or Monophyllites ; this specimen in all probability represents a new species near to Nomismoceras sprratissimum, Holzapfel; Balatonites sp. ind.; Cera- tites sp. ind. belonging to the group of C. circumplicatus ; Orthoceras sp. ind.” Pa) ‘Lower contorted series. Much crushed and dislocated, dark siliceous limestones, showing a prevalent dip to north-west. A bed of limestone immediately overlying this strongly contorted series contains characteristic Werfen fossils (Scythian stage), e.g., Celostylina werfensis, Witt., Terebratula sp., Gervillia exporrecta, Leps., Pseudomonotis venetiana, Hauer, P. aff. leptopleura, Witt. This Scythian stage is widely distributed in the north-west Cancasus, e.g. in the valley of the Bielaya River near the confluence with its tributary the Dakh River, in many places in the Sokhra Valley (another tributary of the Bielaya), on Mt. Shayshin, and on the slopes of Mt. Tkhach. / on Trias and Carboniferous in the Caucasus. 561 The discovery by Messrs. Wittenburg and Robinson of these Werfen Beds in the Caucasus emphasizes the importance of the Caucasian Trias as a connecting-link between the Trias of the Alps and the Himalaya, for beds of this period have long been known to occur at Julfa in the Araxes Valley (which separates Russian Armenia from Persia), containing J-vekoceras and species of Pseudo- monotis, which Bonnet (Bull. Soc. Géol. France, sér. 4, xii, 312) has shown to be allied to those of the Hedenstroemia beds of the Himalaya. The upper, unfossiliferous part of the Julfa Series, consisting of 200 metres of marly limestones overlain by 1,000 metres of black limestones and dolomites, is probably equivalent to the Middle and Upper Trias of the Caucasus. Still more recently W. N. Robinson (op. cit.) in 1912 was able to establish the fact that the Triassic beds of the Caucasus overlie Upper Carboniferous limestones, as at Julfa. The locality is also in the basin of the Bielaya River, at Mt. Gepho on the left bank of the River Kisha (Choga), a right tributary of the Bielaya. Mt. Gepho rises to a height of 1,200 feet above the Tegen stream, which flows into the Kisha, and the natural section discloses the following downward succession :— 1. Trias (Ladinian).—(1) Grey, arenaceous flagstones with plant- remains and badly preserved fossils (not specified). Similar sand- stones (dipping 70° N.E.) occur on the western spur of the Pshekish ridge. To the north-east the sandstones are dark red, very micaceous, and attain a considerable thickness. (2) Conglomerate of small pebbles, mostly of quartz, but it varies considerably in thickness and materials; it extends nearly to the summit of Mt. Gepho and dips west. This conglomerate uncon- formably overlies the Carboniferous Limestone and is greatly developed along the northern slope of the Caucasus in the Kuban district. To the north-west it crops out in the Bielaya Valley, a little above Khamyshki (Alexievsk), and to the south-east as far as the Urups River and the upper course of the Zelenguk. Between the Bielaya and the Little Laba the conglomerate forms a large anticline and composes the ridges Pshekish and Bambak and the southern slope of the Mastakan ridge; it occurs also on the south- west side of the Dudugush ridge towards Mt. Oshten. 2. Upper Carboniferous.—(1) Grey limestones, forming rocky cliffs on both sides of the Tegen defile. They are so compact that the dip is scarcely visible, but in one place it seems to be southerly. They contain a rich Brachiopod fauna, e.g. Hntetes contractus, Gemm., EL. carniolicus, Schellw., Uncinulus velifer, Gemm., Reticularia lineata, Mart., Chonetes uralica, MOll., Notothyris exilis, Gemm., Richthofenra lawrenciana, de Kon., Aulosteges, Geyerella, with Pelecypods, Gastro- pods, and sponges belonging to the families Spheerospongidee (Hetero- celia) and Spheeroceelidee (Sollasia, Stecnmannia). (2) Black, argillaceous slates, forming the bed of the Tegen River, with intercalated, thinly laminated, black sandstones, dipping rather steeply to the south. They are extensively developed to the south- west, south, and south-east of Mt. Gepho, towards the main axis of the Caucasus. No fossils occur in the slates; but the interbedded DECADE V.—VOL. X.—NO. XII. 36 562 Reviews—Professor J. W. Gregory— sandstones (in the Kozi Valley) contain a few _ undetermined Gastropods and Pelecypods. The southerly dip of the slates is maintained over a wide area, and it is only on the south-west slope of the granite ridge Juga (Cheleps) that an anticlinal fold occurs with a steep dip to north-east. The axis of the anticline reveals crystalline schists, which form the bed of the Kisha River near Dokhmat Sheklan. This fold does not, however, extend far either to north-west or south-east. W. N. Robinson attributes the formation of this small fold to the intrusion of the granite. The second outcrop of Upper Carboniferous was observed 2 miles S.S.W. of the confluence of the Little Laba and Urushten Rivers. The limestone is greyer than on Mt. Gepho, and forms an anticline ; in its axis mica-schists and other crystalline schists are visible. To the south this Upper Carboniferous Limestone is overlain by con- glomerate (probably Triassic), and higher up the Urushten River red Triassic limestones form ‘vertical cliffs on both banks. The Upper Carboniferous Limestone contains the following fossils: Spzrefer cameratus, Morton, Reticularia lineata, Mart., Uncinulus velifer, Gemm., Productus gratiosus, Waag., P. pseudomedusa, Tschern., Pelecypods (Macrodon, Edmondia, and Lima), and sponges (Heterocelia). Probably a large portion of the Paleozoic schists of the main axis of the Caucasus will be found to belong to the Carboniferous, and it may be mentioned that a crushed Calamites was found by Inostranzeft some years ago in the Central Caucasus to the north of the main axis. dev dal WAITS WS eadeE elt I.—Tue Narore anp Oriein or Frorps. By Professor J. W. Grecory, D.Sc., F.R.S. 8vo; pp. xvi, 542, with 8 plates and 84 text-illustrations. London: John Murray, 1913. Price 16s. net. fY\HIS is a big book on a subject which, at first sight, seems hardly to justify such voluminous treatment; nevertheless, the author finds plenty to say. His travels have extended over wide areas of the globe, and he deals not only with the typical fiords of Norway, but with the fiords and other sea-inlets or drowned valleys, from Scotland, Greenland, and Alaska to Patagonia, Antarctica, and Australasia. Printed in bold type and well illustrated, the subject as expounded by Professor Gregory is of very great interest to geographer and geologist, and will doubtless be attractive to all travellers and students who seek to become acquainted with the origin of scenery. Apart from scenery, the author points out the influences of fiords since early times on navigation, the distribution of population, and the welfare generally of mankind. We have been accustomed to look upon fiords, sea-lochs, and estuaries as for the most part drowned valleys excavated by rivers and in many cases also largely by glacial action, the resultant features being due to the effects of erosion on rocks of varying altitude, structure, and lithological character. Thus fiords occur among the The Origin of Fiords. 568 hard rocky mountainous regions of Norway, and equivalent sea-lochs are found in similar regions in Scotland; broader rocky channels occur in less elevated grounds in some parts of Devon and Cornwall ; and water-filled valleys with still gentler slopes characterize the coastal regions of Hampshire. No question, however, arises with regard to submergence in connexion with these inlets. The problem is the origin of the main terrestrial features, which may have been due to quite different causes; hence a grouping of the sea-inlets is desirable, more especially as the terms gulf, bay, sound, loch, and firth, as the author points out, are loosely applied to different features. He would class the sea-drowned valleys into three main types: fiords, fiards, and rias. A fiord is described as ‘‘a long inlet which extends far inland~ between steep opposing walls; it usually consists of long straight reaches, which turn and receive their tributaries at sharp and regular angles; and its walls are high, as fiords are restricted to mountain regions”’. Furthermore, there is ‘‘a rarity of bays and a scarcity of sites for human settlements” as there is little or no margin between wall and water, except small tracts at the head, or small deltas along the sides of the fiords. They are characteristic of dissected plateaus, and ‘‘streams flow gently across the uplands until they reach the fiord-wall and then plunge down in picturesque waterfalls ”’. Fiards ‘‘ usually have no large rivers draining into them’’. They ‘Care due to a lowland area with an irregular surface of hard rocks, having been partially submerged beneath the sea. The essential difference between fiards and fiords is that fiards are characteristic cf coast-lands which rise but slightly above sea-level ”’. Rias are ordinary river estuaries, and the author adopts the Spanish term, as such drowned valleys are well represented in North-Western Spain. The rias and fiards are alike ‘‘in having curved lines, gentle slopes, and indented shores”. It is admitted, however, that it is difficult to establish sharp distinctions between fiords and other arms of the sea; fiords pass gradually into fiards and rias, the changes: being due to modified conditions, such as increased submergence. It is pointed out that most fiords occur in the more northern and southern areas of the globe, that they are in fact best developed in regions that have béen subjected to glacial action. Hence it is not surprising that the excavation of the deep valleys has been attributed to glacial action. . The personal observations of Professor Gregory, fortified by a study of the writings of those who have examined special areas in detail, have led him to conclude that while ‘‘fiords are clearly valleys, of which the lower ends have been drowned by the sea’’, nevertheless ‘« all the fiord-systems of the world owe their characteristic features to earth-movements, and not to glacial action’. Moreover, ‘‘river- action will not produce fiords.”” It must be borne in mind that the deepest fiord, in Patagonia, is 4,250 feet, and that the Sogne fiord in ~ Norway descends to nearly 4,000 feet, with bordering walls 3,000 to 4,000 feet high. There is no doubt that many fiords were once occupied by ice, and that much shattered and weathered rocky material was then cleared 564 Reviews—Prof. J. W. Gregory—The Origin of Fiords. away so as to enlarge the valleys. It is contended that the plans of fiords and sea-lochs cannot be explained by glacial erosion, partly because ‘‘the course of the fiords is inconsistent with the lines of flow of the chief glaciers ”’ or ice-sheets; but here the effects of the local glaciers may have been subsequently checked by the invasion of the more extensive sheets of ice. Fiords, however, are not limited to areas that have been glaciated, and they are not always found in regions where, if due mainly to ice-action, they should be expected. With regard to river-action, it is pointed out that fiords are not the outlets of the main rivers, that in fact ‘‘ their existence depends on the absence of large rivers, which would fill them with sediment and give them the form of ordinary valleys by wearing their walls into long, gradual slopes’’. Here, of course, the geological structure and physical features are largely responsible, as in the case of much of the Western Highland area, where the steep slopes and rapid drainage prevent the formation of large rivers. The plan of the chief fiord systems of the world is stated by Professor Gregory to be essentially the same. Fiords occur in trough- shaped valleys that are arranged along a kind of angular network ~ caused by intersecting lines of fracture. This structure was produced by the uplift of the areas to form plateaus: disturbances begun in Miocene but carried out mainly in Pliocene times. The areas of hard rocks were then more or less shattered and cleft by cracks, and subsidence took place of belts of country along the fissured grounds, the troughs or deep basins being. formed by irregular movements in Pre-Glacial times. The author refers much excavation to the Pliocene period. In any case, if erosion were commenced so early, it was continued during Pleistocene times by glaciers and other agents. Here it may be mentioned that in referring to Plymouth Sound, Mr. Clement Reid has remarked that its rocky floor shows a de- pression far greater than we meet with in ordinary Pleistocene valleys, and ‘‘represents not improbably a Tertiary basin ’’.* Mr. J. B. Hill also, as quoted by Professor Gregory, has remarked concerning certain valleys and inlets of Southern Cornwall that ‘‘ the straightness of some of them, and in other cases their parallelism, suggests that their course has frequently been determined by lines of dislocation or well-marked joints’’. Dr. Nansen might also have been called as a witness to the influence of earth-movements in Norway. He has stated that ‘‘the longitudinal valleys and fiords of the land surface as well as of the sea-bottom outside, indicate a system of ancient folds and perhaps faults, possibly formed simul- taneously with the uplift of the northern Norwegian mountain chain, or the original subsidence of the bottom of the sea-basin outside’”’.” Earlier observations, however, by Kjerulf, and the more recent researches of Dr. Sederholm and of others, receive full consideration, and the main features of the Norwegian fiords are illustrated in admirable photographs by Mr. H. W. Monckton. 1 Submerged Forests, 1913, p. 84. * Norwegian N. Polar Haxpedition 1893-1896, Scientific Results, vol. iv, p- 56, 1904. Reviews—Mineral Kingdom— World's Minerals. 565 _ Particulars are given of the fiards of Sweden, the sea-lochs and freshwater lochs of Scotland, and of drowned valleys in regions too numerous to mention. Canons, rock-basins, and various problems of glacial erosion are also discussed, so that the author has supplied much material of profound geological interest, and much in support of his contention that fiords owe their main features to earth- movements. I1.—(1) Tue Mineran Kinepom. By Dr. Ruzinnarp Bravns, Professor of Mineralogy in the University of Bonn. Translated, with additions, by L. J. Spencer, M.A., F.G.S., Mineral Depart- ment of the British Museum. 4to; in 25 parts, pp. 432, with 91 plates (73 of which are coloured) and 275 text-figures. Stuttgart, Fritz Lehmann and afterwards J. F. Schreiber; . London, Williams & Norgate; 1908-12. Price 2s. per part and £2 16s. for the bound volume. (2) Tue Wortp’s Minerats. By Leronarp J. Spencer, M.A., F.G.S. (editor of the Mineralogical Magazine), Mineral Department, British Museum. 8vo; pp. 212, with 40 coloured plates and 21 diagrams. London and Edinburgh: W. & R. Chambers, Ltd., 1911. Price 3s. 9d.; American edition $2.00. WO works on mineralogy have recently appeared, both bearing the name of L. J. Spencer, M.A., F.G.S., upon their title-pages. For the smaller of these volumes, Zhe World’s Minerals, Mr. Spencer is alone responsible. But the larger work, Zhe Mineral Kingdom, published in quarto form in twenty-five parts, now completed, is an | English version of Dr. Reinhard Brauns’s Ifineralreich, translated, with additions, by Mr. Spencer. These two names standing together upon the title-page suffice to vouch for the excellence of the volume. A former work by Dr. M. Bauer, Hdelsteinkunde, 1896, also translated by Mr. Spencer, Precious Stones, 1904, having been now for some years in the hands of English students, has become a standard book for those who work in precious stones. _ The Mineral Kingdom contains ninety-one plates, seventy-three being coloured ; these give excellent representations of the various minerals. It seems almost a pity, from the artistic standpoint, to heighten the coloured figures of metallic ores by gilding and silvering, when such beautiful results are obtained by the modern photographic reproductions without gilding, although it is certainly very skilfully introduced in this work. The plates will be of great practical value, particularly to those workers whose opportunities do not enable them to consult actual specimens in public collections.’ In addition there are 275 figures in the text which greatly increase the value and utility of the book to any one whose work or pursuits bring them in touch with some branch of mineralogy. It is interestingly written, and the explanations are clear and easy to understand. In addition to a full description of each mineral species, the dates of their discovery, methods of identification, testing, and working, economic uses and - geographical distribution, all find a place in these pages. The classification of minerals is somewhat unusual, Zhe Mineral Kingdom being divided into four great parts. The first of these 566 Reviews—Dr. H. R. Mill’s Physiography. includes all metallic ores and their associates. Under this head minerals which have a special interest for the miner are described, commencing with gold. After first giving a short archeological account of the precious metal, the authors then proceed to deal with its mode of occurrence, methods of testing, geographical distribution, ete. Platinum is next dealt with, then silver, copper, mercury, lead, zine, antimony, bismuth, arsenic, sulphur, iron, manganese, nickel, cobalt, tungsten, molybdenum, uranium, tin, and titanium. There is also a short appendix dealing with meteoric irons and stones. Precious stones and related minerals is the next heading. This section comprises all the minerals with which the jeweller is con- cerned, from the diamond to ‘common quartz’. These, which were fully dealt with from that standpoint in Ldelsteinkunde, are here described from their mineralogical aspect chiefly, although methods of cutting, historical, and other points of interest are touched upon. Part ii1 consists of rock-forming silicates and allied minerals. This section, apart from its purely scientific side, is one which is of interest to architects and workers in stone. Here the preparation of suitable sections for microscopic study of rock-structure is explained, and the various rock-forming minerals are described. The last class is entitled ‘ mineral salts’. Several mineral substances of great commercial value are dealt with under this heading, but it also includes that group so attractive to the amateur, the fluorspars. In The Worlds Minerals Mr. Spencer gives short descriptions of the minerals figured. The forty plates are also coloured, which is a great help to the inexperienced collector, to whom this book should prove most acceptable. The plates do not equal those in the larger work, and space of course does not allow of much more than one figure for each of the 116 mineral species described; in some cases the student would be glad of more illustrations to aid in identification. The introductory chapters are helpful and simply expressed, giving a short explanation of crystallographic systems, the physical characters of minerals, and their chemical composition and classification. I1].—Puysrocrapny. THe Reatm or Nature; aN OvTiine or Puysioerapuy. By H. R. Mitt, D.Sc., LL.D. Second edition. 8vo; pp. xii, 404, with 19 coloured maps and 78 figures in text. London: Murray, 1913. Price 5s. net. ({\HE usefulness and popularity of the first edition of this book is evident from the fact that it has been reprinted no less than six times since its appearance in 1891. This edition has been thoroughly revised page by page, and can be justly recommended to the reader. The author sets forth to illustrate the principles of science by applying them to the world we live in, and to explain the methods by which our knowledge of Nature has been acquired and is being daily enlarged. The greater part of the book is occupied by an outline of the more important facts regarding the structure of the universe, the form, material, and processes of the earth, and the relations which they bear to life in its varied phases. Reviews— Dr. A. P. Coleman—The Nickel I ndustry. 567 The headings of the chapters run as follows: Study of Nature; Substance of Nature; Energy, the Power of Nature; the Earth a Spinning Ball; the Earth a Planet; Solar System; Atmosphere, its Phenomena; Climates; Weather and Storms; Hydrosphere ; Ocean Bed; Crust of Earth; Action of Water; Record of the Rocks ; Continental Area; Lite; Man. The maps are clearly printed and valuable, and show magnetic conditions, earthquake regions and volcanoes, isotherms, isobars, winds, rainfall, salinity of oceans, con- figuration of globe and coastal lines, drainage areas, evolution of continents, ocean-surface isotherms, coral reefs, rising and sinking coasts, vegetation zones, and biological regions. It is one of those handy volumes the usefulness of which becomes daily more apparent, and the price greatly assists its recommendation. It has an index, but the worker will add to this for his own con- venience such words as maelstrom, dunes, travertine, stalagmite, stalactite, metric system, zero, rigidity, atomic weight, lodestone, ete., which to publishers do not seem to be of any importance. IV.—Tue Nicxen Inpustry: WITH SPECIAL REFERENCE TO THE Suppury Rezeion, Ontarro. By A. P. Coreman, Ph.D., F.R.S. Department of Mines, Canada, No. 170, pp. vi1+ 206, with 14 text-figures, 63 plates, and 8 coloured maps. Ottawa, 1913. URING recent years the Canadian Department of Mines has issued several useful monographs on various minerals of economic importance which occur and are mined in the Dominion, and the present volume adds another to this series. The group of mines near Sudbury produces two-thirds of the world’s supply of nickel, the amount for the year 1910 being 18,636 tons of metal, together with 9,630 tons of copper, of a total value of rather over one million pounds sterling. The ore here consists of an intimate mixture of pyrrhotite (magnetic pyrites), pentlandite (a sulphide of iron and nickel), and copper-pyrites, more or less intermingled with rock-forming silicates. It occurs at the base of an intrusive sheet or huge laccolite of igneous rock, and it passes imperceptibly into this. This sheet, consisting of norite in its lower portion and graduating upwards into micropegmatite, is intrusive between the erystalline rocks of the Laurentian and the sedimentary rocks of the Upper Huronian. Its outcrop forms the rim of an oval basin measuring 36 miles along the major axis and 16 miles across, and the several mines in which the nickel ore is worked are situated along the rim of this basin. We have here clear evidence of magmatic differentiation on an enormous scale; the acid rock passing downwards into basic rock, whilst ae the bottom of all are the heavy metallic sulphides. An outline of the physiography and senerl geology of the district and a mineralogical description of the ores is followed by an historical sketch of the mining industry, and detailed particulars relating to — each of the several mines now working. Although the occurrence of nickel in this district was first recorded in 1856, it was not until 1884, when large bodies of ore were exposed in the cuttings of the 568 Reviews—Professor Doelter’s Mineralogy. Canadian Pacific Railway, that mining operations were commenced. Curiously, however, the mines were first worked for copper (the principal nickel- producing firm still being the Canadian Copper Company), but it was soon found that the presence of nickel interfered with the extraction of the copper; and, indeed, it was not until about that time that nickel came to have any commercial value. Detailed descriptions are also given of the methods of mining, of the mechanical treatment of the ores, and of the metallurgical processes. The occur- rence and treatment of nickel ores in other parts of the world, principally in New Caledonia and Norway, are also dealt with. Finally, there is a short account of the uses of nickel in coinage (though not in Canada), but particularly in nickel-steel and other alloys. No mention is, however, here made of the extensive use of nickel salts in electroplating. V.—Proressor Dortrer’s Mineraocy. Hanpsucn per Mineratcuemiz. By Hofrat Prof. Dr. C. Doxrrrer. Bd. III, i, pp. 1-160. 8vo. Steinkopf: Dresden and Leipzig. Price 6.50 marks. HE first part of the third volume of this work deals with the oxides of titanium, zirconium, niobium, tantalum, and their compounds with silica. The quantitative separations and estimations of these oxides present many problems of grave difficulty to the chemist. The various methods in use are described and discussed by Dr. K. Peters, in addition to which there are special articles on the analysis of lavenite, eudialyte, johnstrupite, and catapleite by Dr. R. Mauzelius, and on the analysis of euxenite by Dr. G. T. Prior. Dr. R. Pribram contributes a section on the chemistry of germanium and the minerals in which it occurs. A very interesting chemical problem is the composition of the rare mineral striiverite, which Dr. Prior has shown to be isomorphous with ilmeno-rutile: both minerals are regarded as solid solutions of tapiolite or mossite (iron tantalate and niobate) in rutile. It is suggested that the name striiverite be reserved for those members of the series in which tantalic acid preponderates over niobic acid, those richer in the latter being called ilmeno-rutile. The determination of both tantalum and niobium in the presence of large amounts of titanium thus becomes a problem of great importance: this problem has now been successfully solved by Hess and Wells in America and more recently by 8. J. Johnstone in London. Another group of minerals of great interest are the three forms of titanium dioxide ; rutile, anatase, and brookite. To account for the existence of these three forms many theories have been advanced ; these theories still await definite proof, for while recent analyses of rutile are fairly abundant, only two analyses of anatase and brookite appear to have been made within the last fifteen years. The brookite analysed by Rose in 1844 and said to have come from Snowdon, ‘Wales, was doubtless from the well-known locality for that mineral near Tremadoc. Professor Doelter himself has contributed very largely to this part Reviews—Geology vm the Congo. ‘569 in articles on special minerals, perhaps the most important being the section dealing with zircon. Some varieties of this mineral show considerable departures from the usual formula, Zr O,. SiO, ; artificial erystals of the composition 3 Zr O,. 2 Si O, have been scenes. and it is suggested that some such eoHicnp hone eee. may occur in nature. The variations in density and refractive indices of zircons, and the effect of heat, light, and radium on stones of various colours are discussed. Zircons can be divided roughly into two classes, red and brown stones on the one hand and green stones on the other. The green stones are usually less dense and have lower refractive indices than the brown ones, and at present no satisfactory explanation of these differences has been reached. As regards the colour, Professor Doelter and others have shown that the brown stones are decolorized when strongly heated, the colour returning under the influence of radium emanations, but both heat and radium are without appreciable effect on the green zircons. The inference drawn from these facts is that the brown colour is due to a radio-active constituent of the zircons, while the green stones owe their colour to some more stable substance. VI.—Grotocy In THE Conco. ANNALES DE LA Soclitk GkoLociguE DE BexteruE. Publications — relatives au Congo Belge, 1912-138, pp. 75-125. (J\HE Geological Society of Belgium are to be congratulated on the work which their members are doing in the Congo, and which they are now publishing in an appendix to the annals of the Society. The second part of this special publication contains details of a boring passing through 80 metres of the Lualaba Series, observations on the lower part of the Lubilache Beds, and a second series of M. Buttgen- bach’s contributions to the petr olog ey of the district. M. Mercenier, working in the neighbourhood of Albertville on the west of Lake Tanganyika, has traced a series of great faults running approximately parallel to the Tanganyika depression. M. Cornet has previously demonstrated the existence farther to the west of another great depression some 200 kilometres in length, which he has called the Upemba ‘‘graben”’. In a preliminary note by M. Delhaye on the Katanga district we find evidence of yet another great series of trough-faults causing the depression of the Lufira River. M. Mathieu, in a paper on the hot springs of Lower Katanga, shows that the distribution and characters of these springs bear a relation to the areas of depression. He records the temperature and mineral composition of these springs throughout the area, and shows that these characters are closely related to their distribution. Thus the hot springs of the Tanganyika depression have a temperature of 40-55° F., are highly charged with chlorides, sulphates, and soda, and contain relatively little carbonate: those of the Upemba depression, on the other hand, have a temperature of 70-100° F., are not highly mineralized, and carbonates preponderate over’ chlorides and sulphates. Springs of the first group appear to be connected with eruptive rocks; those of the second group occur mainly at contacts of the quartzites with granitic rocks. 570 Reviews—Brief Notices. VII.—Brier Noricss. 1. On THE SKELETON OF ORNITHODESMUS LATIDENS: AN ORNITHOSAUR FROM THE WEALDEN SHALES OF ATHERFIELD, Isle of Wight. By R. W. Hootry. Quart. Journ. Geol. Soc., vol. lxix, pp. 372-422, pis. xxxvi—xl, 1913. In this important paper Mr. Hooley gives a very complete description of a new species of Pterodactyl, founded mainly on a remarkable specimen in which the bones are most perfectly preserved and quite uncrushed. ‘The author was able to remove the very hard matrix to such an extent that he could find by actual trial the natural motions of the bones on one another, and in this way to study the mechanics of the reptile’s wings. The type is a very remarkable one and of great interest, because it represents an extremely large animal, spread of wing about 5 metres, belonging to quite a different group from the other well-known large types, the toothless Ornithostoma of the Kansas Chalk. ‘The paper concludes with a discussion of some points in the structure of Pterodactyls and of their classification in the light of this new type. 2. REKONSTRUKTIONEN DES FLucsaurRiers, RHAMPHORHYNCHUS GEM- mine, H. v. M. By Ernst Srromen, of Munich. Neues Jahrbuch fiir Min. Geol. u. Pal., January, 1913, Bd. ii, 8. 49-68, Taf. ili-v. An important paper, dealing with many points in the osteology of Pterodactyls, illustrated by a beautiful drawing of a restoration of the skeleton, and photographs of a remarkable life-size model of the skeleton from three aspects, which give a much better idea of the build of a long-tailed Ornithosaur than has previously been possible. 3. On some New Genera AND Spectres oF Dicynopont RepriLes, WITH Nores on a FEW orHERS. By R. Broom. Bull. Amer. Mus. Nat. Hist., vol. xxxil, art. xxvi, pp. 441-57. A description of three new genera and thirteen new species of Dicynodont reptiles. The specific and generic characters are mostly drawn from the features of the top of the skull in the pineal region, particularly from the relations of the pre-parietal, which are illustrated by clear figures. 4. Nore on Houus capensis, Broom. Bull. Amer. Mus. Nat. Hist., vol. xxxil, art. xxv, pp. 437-9. A description of upper premolar (pm.*) of the large &. capensis, which is found associated with the extinct Bos baint, Connochetes antiquus, Colus ventere, and human implements. 5. On Evrpence oF a MammMat-trikeE Denrat Succession IN THE Cynopont Reprines. By R. Broom. Bull. Amer. Mus. Nat. Hist., vol. xxxii, art. xxvill, pp. 465-8. Dr. Broom describes a specimen which appears to give satisfactory evidence of the replacement of canines, incisors, and milk molars in Diademodon, a discovery of very great importance, as hitherto, . although examples of Therocephalia, Gorgonopsids, and Cynodonts showing replacements of the canine have been fairly common, and Reviews—Brief Notices. 571 specimens showing replacements of the incisors known, none have shown any replacement of cheek-teeth, a fact which has told somewhat against the relation of these types to mammals. It now seems probable that the group will show us all the stages, from the indefinite replacement of teeth in the ordinary reptilia to a very definite replacement similar to that occurring in mammals. The specimen is perhaps not absolutely conclusive, but affords very considerable reasons for believing that Dr. Broom’s interpretation is correct. 6. On rae Origin or THE CHEIROPTERYGIUM. By R. Broom. Bull. Amer. Mus. Nat. Hist., vol. xxxu, art. xxvii, pp. 459-64. A description of the well-known fin of Sauripterus taylori, and the suggestion that the Tetrapod limb may have been derived from such a fin by the development of some of the pre-axial skeletal elements and the loss of the post-axial, which continued to support the fin during the change. 7. Tue Sxurt Exements oF THE Permian TETRAPODA IN THE American Museum or Narurat History, New York. By F. v. Hvenr, Tubingen. In this large paper the author gives short descriptions and figures of many of the types of reptiles found in the ‘ Permian’ of Texas. This paper is important in that it contains the views and criticisms of a distinguished and independent author on many of the disputed facts of structure of these very interesting forms. Dr. v. Huene not only adds to our knowledge by determining many new sutures, but also by redetermining some of the bones figured by Case. The author adds some interesting discussion on morphological points and on taxonomy. 8. Tue Trerten Bear.—Mr. K.-T. Newton has described under the name of Ursus etruscus (= U. arvernensis) a number of teeth from the Pliocene clay of Tegelen-sur- Meuse (Geological Proceedings for Netherlands and Colonies, ’s Gravenhage, 1913). He remarks that “(At present U. etruscus is only known from Pliocene deposits of Europe; but there are indications of somewhat similar fossil forms occurring in India and China, and it may well be that from these Pliocene species the modern Black Bears are descended which to-day are found widely distributed in America and Asia’’. 9. Mr. Curster G. Girpert and Mr. Joseph E. Pogue contribute to the Proceedings of the United States National Museum, vol. xlv, 1913, a paper on ‘‘The Mount Lyell Copper District of Tasmania”’, in which they gave a succinct account of the geology and mode of working the famous copper-mines. The paper, which is the outcome of a study of a representative collection of rocks received in 1910 by the museum from Mr. Robert Slicht, manager of the Mount Lyell Mining and Railway Co., is largely based upon Professor - J. W. Gregory’s well-known memoir. ' 10. Inthe Bulletin de la Société Belge de Géologie, vol. xxvii, 1913, M. A. Ledoux gives the results of an elaborate study of quartz crystals from Belgium, and records altogether eighty-one forms. Twins are very common, and, indeed, etching figures show that 572 Reports & Proceedings—Geological Society of London. simple individuals are rare. Groups of crossed crystals are often met with which are not true twins. The various occurrences—in eruptive rocks, metalliferous veins, quartz veins, and sedimentary rocks—are described in detail. The paper is amply illustrated. 11. Frorine anp Prrrine or Granires.—An interesting and well- illustrated article on this subject, by Mr. J. C. Branner, has been published by the American Philosophical Society (Proc. lii, April, 1913). The fluting of granites and other crystalline rocks appears to be confined to tropical and possibly sub-tropical countries. Striking examples are seen near Quixada, in Ceara State, Brazil, mostly in massive coarse-grained gneissoid granodiorites. The furrows start at or near the summit of the exposed rock, and run straight down the rock-slopes by the shortest possible routes. Some reach a depth of nearly 2 metres measured at right angles to the general surface of the rock-masses. In the same region the fluted rocks have been hollowed into ‘‘ great rounded caldron-like pits, some of which are associated directly or indirectly with the fluting’’. These pits seldom exceed 2 metres in depth and their diameter is about 2 metres. In certain cases they occur in a nearly vertical row, connected by a furrow, and having the appearance of a great irregular staircase ‘mounting the hill. The fluting seems to:occur only on steep slopes, with an angle of 45° or more, and it 1s caused by the rainfall, small in amount, that acts in part chemically, in part mechanically. The pits are formed by the disintegration and dissolution of minerals. cE @ eee Ss AGN 5 =e: @ Cs a eG I.—Gerotoeicat Socrery or Lonpon. November 5, 1918.—Dr. Aubrey Strahan, F.R.S., President, in the Chair. The following communication was read :— ‘‘ Geological Sections through the Andes of Peru and Bolivia.” By James Archibald Douglas, M.A., B.Sc., F.G.S. This paper deals with the geological structure of the South American Andes, as illustrated by a horizontal section drawn from the port of Arica in the extreme north of Chile (formerly Peruvian territory) across the mountain-ranges or ‘ Cordilleras’ to the forested region of the Amazon slopes, in the district known as the Bolivian ‘Yungas’, following the route of the new Arica—La Paz railway, which was under course of construction at the time of the author’s visit. It is the partial result of two years’ geological exploration in Peru, undertaken on behalf of Mr. W. E. Balston, F.G.S., for the Oxford University Museum. After a description of the general physiography of the Peruvian Andes, the topographical features of the country traversed by the railway are discussed in some detail. Its geological structure is then described under three headings: (1) The Mesozoic sediments of the coastal region with their contem- poraneous igneous rocks, the intruded core of granodiorite, and the Reports & Proceedings—Geological Society of London. 573 overlying recent volcanic rocks of the Western Cordillera. (2) The voleanic rocks of the Mauri River, the Mesozoic and Paleozoic sediments of the ‘ Altaplanicie’ and the Titicaca district; the line of dioritic intrusions, and the Pleistocene gravels of the Desaguadero River. (8) The Paleozoic rocks and granitic core of the Eastern _ Cordillera and the Amazon slopes. (1) The Mesozoic stratified rocks are well exposed in the ‘ Morro de Arica’, where fossils occur which indicate an Upper Jurassic (Callovian) age. They are interbedded with thick sheets of basic enstatite-andesite, showing well-marked ‘ pillow’-structure ; this rock is remarkably fresh, and free from albitization. Similar stratified rocks are traced up the Llutah and Palca river- valleys. In the former they are penetrated by a thick intrusion of quartz-hypersthene-norite, which, it is suggested, is the plutonic equivalent of the pillow-lava of the coast. _ The erosion of the river-valleys that has brought to light the Jurassic sediments has also laid bare the underlying plutonic mass of granodiorite, which may be regarded as the deep-seated core of the Western ‘Cordillera’. This plutonic mass appears to have been intruded in the form of a batholite in post-Cretaceous times. The Western Cordillera is essentially a volcanic range, formed of numerous more or less isolated, snow-capped, dormant, and extinct voleanoes, attaining heights of 19,000 to 20,000 feet. The enormous amount of volcanic material emitted from these cones has almost completely concealed the underlying rocks. The lavas can be resolved into three main groups, characterized by their dominant ferromagnesian mineral, succeeding one another in _ age according to a law of increasing basicity: (a) acid rhyolites and tuffs with biotite; (6) trachytes and trachy-andesites with hornblende, typically developed in the district of Mount Taapaca; (c) andesites and basalts with pyroxenes, forming the cones of Mounts Tacora and Chupiquina. (2) The western part of the high-level Bolivian plateau, or ‘ Altaplanicie’, is almost entirely covered by vast horizontal sheets of volcanic ash, tuff, and pumiceous lava, described as the Mauri Volcanic Series. These rocks have often the appearance of ‘ trass’, and it is suggested that they have been formed in large part as subaqueous deposits. The occurrence in an interbedded layer of gravel of a fragment of a jaw of ‘ Wesodon’, almost identical in — appearance with specimens from the Miocene beds of Santa Cruz, affords the only clue for an estimation of their age. They are overlain on the east by gravel deposits of the Desaguadero River, the highest terrace of which was found to contain remains of Mastodon, Megatherium, Scelidotherium, and other Pleistocene vertebrates. From beneath these superficial deposits crops out a series of un- fossiliferous red and chocolate-coloured sandstones and conglomerates. After comparison with other districts on the north, these are divided into two groups—a younger gypsiferous sandstone and marl series of Cretaceous age, broken through by a line of dioritic intrusions and resting with pseudoconformity on an older Permo-Carboniferous group. The latter ends abruptly along a fault-line against vertical 574 Reports & Proceedings—Zoological Society of London. shales and quartzites, containing a few characteristic Lower Devonian fossils. These Devonian beds, though much concealed by alluvial plains, form the basement of the eastern part of the ‘ Altaplanicie’. The Carboniferous formation is nowhere exposed along the line of section, but an account is given of its development in the region of Lake Titicaca, where the limestones contain an Upper Carboniferous or Permo-Carboniferous marine fauna. A short discussion is entered into on the theory of the recent elevation of the Andes and the origin of Lake Titicaca. (3) The Eastern Cordillera rises to heights of over 22,000 yee being composed chiefly of steeply dipping Devonian slates and quartzites, though many of the unfossiliferous black slates and greywackes of the eastern slopes most probably may be referred to the Silurian, or even to an older formation. Outcrops of granite are of rare occurrence along the line of section, although there is reason to suppose that this rock forms the core of most of the high peaks. As marine Lower Carboniferous and Upper Devonian rocks are absent from this district, it is suggested that the granitic core was intruded during a period of land-elevation at this time. II.—Zoonogicat Society or Lonpon. October 28, 1918.—Professor E. A. Mincutn, M.A., F.R.S., F.Z.S., Vice-President, in the Chair. 1. Dr. F. A. Bather, M.A., F.R.S., F.Z.8., read a paper entitled ‘‘The Fossil Crinoids referred to Hypocrinus, Beyrich”’. The two specimens of Hypocrinus schneidert, Beyr., described by Beyrich and Rothpletz respectively, are redescribed and refigured. The structure of the genus is shown to agree with that of the Devonian family Gasterocomide, the content of which is discussed; but it is suggested that in this case and in that of ‘ Lecythiocrinus’ adamst the distinctive features may have been independently acquired. The holotype of Hypocrinus pirtformis, Rothpletz, is redescribed and refigured, and proved to be no Hypocrinus. It is thought to be a highly modified descendant of the Taxocrinide, by way of such a genus as Cydonocrinus. The left posterior radial appears to have borne a large arm, but the other arms are more or less atrophied, and the right posterior radial has almost disappeared. 2. A paper on ‘‘ Batrachiderpeton lineatum, Hancock & Atthey, a Coal-measure Stegocephalian’’, communicated by Professor J. P. Hill, D.Sc., F.R.S., F.Z.S., was read by Mr. D. M. S. Watson, M.Se. It contained the description of the skull, lower jaw, and pectoral girdle of this species, based on a series of specimens in the Newcastle Museum, derived from the Low Main Seam of Newsham Colliery. 3. A paper, communicated by Dr. C. W. Andrews, F.R.S., F.Z.S., was received from Mr. R. W. Palmer, M.Sc., entitled ‘‘ The Brain and Brain-case of a Fossil Ungulate of the genus Anoplotherium” in which a cranium from the Phosphorites of Quercy, together with an exceptionally perfect and well-marked brain-cast obtained from it, were described from material in the British Museum collections. Obituary—Henry Franklin Parsons. 575 OBLDTUARY. HENRY FRANKLIN PARSONS, M.D., F.G.S. BORN FEBRUARY 27, 1846. DIED OCTOBER 29, 4913. We much regret to record the death, at the age of 67, of Dr. Franklin Parsons, F.G.S., a medical officer who was distinguished for his extensive knowledge and wide experience of sanitary science, who was an enthusiastic worker in geology, and an expert botanist. He was born at Beckington, a village about 8 miles north-east of Frome in Somerset, and was the eldest son of Joshua Parsons, a surgeon, who took much interest in the natural history of the district. The geological features are extremely varied, as within a walking distance of Beckington there can be studied the Old Red Sandstone and Carboniferous rocks, the Trias, Lias, most of the Oolitic rocks, and Upper Cretaceous strata. After education in private schools Franklin Parsons proceeded to St. Mary’s Hospital, and subsequently took high honours in medical subjects at the University of London, with the degree of M.D. in 1870. From 1867-73 he was engaged in medical practice with his father at Beckington, and devoted most of his leisure to the study of geology and botany. Some of his observations were communicated later on to the Somersetshire Archeological and Natural History Society in a paper on ‘‘ The Flora of Hast Somerset” (1875), wherein he pointed out the relations between the geology and the distribution of the plants, and in another paper on the ‘‘ Geology of the District around Bruton’’ (1879). | In 1874 Dr. Parsons was appointed Medical Officer of Health for the combined districts of Goole and Selby, in Yorkshire. Here he turned his attention to local natural history, to the warp of the Humber and its diatoms, the results being given to the Geological Society of the West Riding in papers on ‘‘ The Maritime Plants and Tidal Rivers’ (1876), and on ‘‘ The Alluvial Strata of the Lower Ouse Valley ” (1878). To the same Society he also communicated a paper on ‘‘ The Trias of the Southern Part of the Vale of York” (1879). Dr. Parsons was married in 1879 to the daughter of the late John Wells, J.P., of Booth Ferry House, Yorkshire, and the same year was appointed a Medical Inspector on the Local Government Board. In this department he was frequently engaged on sanitary questions in which his knowledge of geology was of great practical service, aS In connexion with sites for cemeteries and sewage-farms, with water-supply, pollution, and sundry epidemics. He prepared a ‘‘Memorandum on the Sanitary Requirements of Cemeteries”, which was issued by the Local Government Board in 1880 and revised in 1906. In 1892 he became Assistant Medical Officer, being second in command on the Medical Staff of the Board, and this post, which included that of Inspector for General Sanitary Purposes, he held until his retirement early in 1911. Among his many official publications it will be appropriate here to mention his ‘‘ Report on Geological Considerations in relation to Public Health and Sanitary Administration”? (30th Ann. Rep. Loc. Goy. Board for 1900-1, 1902, p. 258). When President of the Epidemiological Society he 576 Miscellaneows. delivered addresses on ‘‘ Half a Century of Sanitary Progress and its Results”? and ‘‘On the Comparative Mortality of English Districts ’’. As remarked in the Zancet (November 8, 1918, p. 1856), ‘‘he probably influenced the sanitary development of this country more than anyone else.” He was Examiner in Hygiene and State Medicine for the University of London, and for the diploma of Public Health at Cambridge. He likewise served on various departmental committees, including the annual Consultatory Committee on the Geological Survey, under the Board of Education. To the Geological Survey he rendered much assistance in the matter of water supply, and his name appears on the title-page of memoirs dealing with the wells and borings in Lincolnshire, Suffolk, Kent, and Sussex (supplement). ‘Dr. Parsons became a Fellow of the Geological Society in 1877, and a member of the Geologists’ Association in 1911. He was an active member of the Croydon Natural History and Scientific Society, usually exhibiting at the meetings of the Geological Section some of the fossils which he had collected. As President for the year 1912 he delivered (on January 21 of this year) an address on ‘‘ Plant Growth and Soil Conditions’’. He BW PROFESSOR DR. ANTON FRITSCH. We regret to record the death of our old friend Professor Dr. Anton Fritsch, Director of the Royal Bohemian Natural History Museum, Prague, which took place on the morning of November 15. Dr. Fritsch had attained his 82nd year, and we hope to give some account of his long scientific career next month. Eft as ere; Shee APppoInrMENT oF NEW Director TO THE GEOLOGICAL SuRVEY AND Musrum.—The President of the Board of Education has appointed Dr. Aubrey Strahan, F.R.S., to be Director of the Geological Survey of Great Britain and Museum of Practical Geology, in succession to Dr. J.J. H. Teall, F.R.S., who will retire from the post on January 5 next. Dr. Strahan, who was born in 1852, was educated at Eton and St. John’s College, Cambridge. . He was elected a Fellow of the Royal Society in 1903, and is President of the Geological Society. He is the Assistant Director of the Geological Survey of England and Wales. Dr. Teall, who was born on January 5, 1849, has been Director of the Geological Survey and Museum since 1901. He is the author of British Petrography, a Description of the Rocks of the British Isles, 1888. Kent Coat-Fretp.—Dr. Malcolm Burr has tabulated and printed in the Colliery Guardian for October 10, 19138, the available information as to the strata revealed by the borings at Tilmanstone, Guildford, Oxney, Maydensole, Ripple, Barfrestone, Goodnestone, Trapham, Woodnesborough, Stodmarsh, Walmestone, and Mattice Hill. We say ‘available’ because, as the author notes, many of the bores being made by chisel there were no ‘cores’ of the softer beds. Detailed reports are promised later by Mr. Arber and Mr. H. Bolton. INDEX. BEREIDDY Bay, etic., 465. Aerolites, Indian, 427. Agates, Structure of, 469. Algz, Caleareous, in Paleozoic and other Rocks, 440, 490, 552. American Journal for Science, 91. Ammonites, Yorkshire Types of, 377. Anderson, Tempest, Obituary of, 478. Andes of Peru and Bolivia, 572. Andrews, Dr. C. W., Bird Remains, Transsylvania, 193; Marine Rep- tilia, Oxford Clay, 219. Anhydrite, Magnesian L., 94. Antarctic Expedition, 144. Arber, EH. A. Newell, Fossil Plants, S. Staffs, 215; Fossil Plants, New Zealand, 231; Floras of S. Staffs Coal-field, 462. Arran, Petrology of, 305. Atlas, Geological, Photographic, 424. Aulophyllum, genus, 41. AHIA, Brazil, Cretaceous Forma- tion of, 356. Bailey, E. Battersby, the Loch Awe Syncline, 189. Ball, John, Geography and Geology of South-Hast Egypt, 266; Phos- phates of Egypt, 425. Ball, Lionel C., Sphenophyllum in Australia, 133. Banton, J. T., Fossil Beads (?), Bed- fordshire Gravels, 138, 190. Bardsey Island, Geology of, 188. Barrington Bone-bed, Cambridge, Minerals of, 252. Barrow, G., Records London Wells, 174; Geology Strathspey, 264 ; Folding in Paleozoic Rocks, 463; Spirorbis L., N. Warwick., 463. Bather, Dr. F. A., A new Crinoid, 346; Caradocian Cystidea, 418. Bathonian Rocks, Oxford District, 282. Beaufort Beds, South Africa, 388. Bembridge Limestone at Creechbarrow Hill, 45. y Bennett, F. J., Home-made Natural Foliths, 47. Benson, W. N., Spilite Lavas and Radiolarian Rocks, 17; Polarizing Microscope, 447. Bermuda Islands, Geology of, 413. Bibliography of North American Geology, 325. Bird Remains, Upper Transsylvania, 193. Bloomfield, A. H., Bembridge L., 45. DECADE V.—VOL. X.—NO. XI. 4 Cretaceous, | Bonney, T. G., The Work of Rain and Rivers, 36; The Structure of the Earth, 37; Volcanoes, 273. Boswell, P. G. H., Age of Suffolk Valleys, 327. Bosworth, T. O., Keuper Marls around Charnwood, 90; South Texas, 481. Brachiopoda, Cambrian, Syringo- thyris, 393. Branchipod Crustacean, a new, Coal- measures, Rochdale, 352. Brauns, R., Mineral Kingdom, 565. British Association, List of Papers, 448; Abstracts, 453, 516. British Columbia, Geological Survey Map, 320. A Human Skeleton from, 364. British Museum, Annual Report, 1912, 527. Brydone, R. M., Proposed Recognition of Two Stages in Upper Chalk, 56; New Chalk Polyzoa, 97, 196, 248, 436; Stratigraphy of Chalk of Hants, 122; Division of the Upper Chalk, 380; Micraster precursor, 430. Buckman, 8. 8., ‘The Kelloway Rock,’ Scarborough, 231; Cam- brian Brachiopoda, 312; Yorkshire Type Ammonites, 377. Buried River Channel, Fletton, near Peterborough, 414. Burrard, Colonel 8. G., The Origin of the Himalayan -Folding, 167; The Origin of Mountains, 385. ADELL & WILSON, Methods of Working Oil-shales, 129. Cainozoic Mollusea, South Africa, 177. Caleareous Algse in Paleozoic Rocks, 440, 490, 552. California University Publications,131. Californian Tertiary Sharks, 324; Eocene Mollusca, 325. Calvert Boring, North Bucks, 469. Cambrian Brachiopoda, C. D. Walcott, 312. Cambridge Philosophical Society, 40, 378. f Camels, North American, 379. Canada, Department of Mines, 130, 320, 426; Building and Ornamental Stones of, 178; Geological Survey Memoir, 319; Mineral Production, 320. Cantrill, T. C., Hstheria, Bunter, South Shropshire, 518. Caradocian Cystidea, Girvan, 418. 37 578 Carbonicole, Structure and Relation- ships of, 279. Carboniferous Beds Basal, of Lye, South Staffordshire, 521. * Carixian,’ Lower Pliensbachian, 401. Carruthers, R. G., Lophophyllum and Cyathaxonia, 49; Oil-shales of the Lothians, 129. Caucasus, Geological Structure, 559. Cellier, J. S., appointed Professor of Mining, Johannesburg, 288. Cephalopoda (Derived), from the Holderness Drift, 137. Chalk Polyzoa, 97, 196, 248, 486. Chalk Upper, Division of the, R. M. Brydone, 380; A. J. Jukes-Browne, 431, Chalk-pebbles from English Channel, 62. Chapman, F'., Geology of Victoria and Tasmania, 133; Hocene Fora- minifera, Hants, 555. ‘Charmouthian,’ A. J. Jukes-Browne, 475. Chatwin, C. P., appointed Assistant Librarian Geolcgical Society, 336. Cheiropterygium, Origin of, 571. Chilean Borate Deposi s, 277. Churchward, Albert, Primitive Man,39. Cimono, E., Sulphur-mines, Italy ,323. Climatic Conditions, Southern Texas, 481. Coal near ‘ Black Hills’, Wyoming, 225. Coal-field, Concealed, Yorkshire and Nottinghamshire, 373. Leicestershire and South Derby- shire, 381. Coal-fields, Development of Midlands, 522. —— Lower Matanuska Valley, Alaska, 225. Cobbold, E. 8S., Paradoxides, 42; Trilobite Fauna, 42; ‘ Cwms,’ Caradoc—Comley, Shropshire, 517. Cenholectypus Cube, Hawkins, sp. nov., 202. Cole, G. A. J., Interbasaltic Rocks of North of Ireland, 86. Coleman, A. P., Nickel Industry, 567. Congo, Annals of, Museum (Belgium), 473, 569. Congress, International Canada, 486. Cornish, V., Transport and Accumula- tion of Detritus by Wind and Water, 455. Corstorphine, Dr. G. S., appointed Principal South African School of Mines, Johannesburg, 288. Geological, Index. Cotter, G. de P., Indian Aerolites, 427. Cotteswold Naturalists’ Field Club,322. Cox, A. H., Abereiddy Bay and Pencaer, Pembroke, 465; Pillow Lavas, North and South Wales, 516. Crampton, O. B., Geology and Forestry, 526. Cretaceo-Tertiary, New Zealand, 286. Cretaceous Bird Remains, 193 ; Lamellibranchia of England, 228; Asteroidea, Evolution of, 230; Dinosaurs, South African, 263 ; Formation of Bahia, Brazil, 356. Cretaceous Fish, Portieuws molossus, Cope, 529. Cribrilina cacus, Brydone, sp. nov., 437. suffulta, Brydone, sp. noy., 436. Crinoidea, a new genus of (Psalido- crinus, RemeS), 346. Crook, T., Septaria: a defence of ‘Shrinkage’ view, 514. Croonian Lecture, Dr. R. Broom, 192. Crosse, A. F., Iridosmine in the Transvaal, 230. Croydon Natural History Society, 39. Croydon’s ‘ Woe Waters’, 144. Cumings, E. R., Monticuliporoids, Position and Development of the, 32. “Cwms’ in Caradoc-Comley Region, Shropshire, 517. Cynodont, Dental Succession in, 570. —— New, from the Stormberg, 145. ANIEL PIDGEON Fund, awarded to R. U. Sayce, 2338. Dapedius granulatus from Lias, Charmouth, 234. Dartmoor, Geology of, 172. Darwin, Sir G. H., Obituary of, 477. . Davies, A. Morley, Origin of Septarian Structure, 99; Deep Borings, North Bucks and North of the Thames, 178. Deeley, R. M., North American and European Drift Deposits, 14; Sub- merged River-valleys, 262. Deep Borings, North Buckinghamshire and North of the Thames, 178. Desert Conditions Past and Present, Professor Walther’s, 132. Detritus, Transport and Accumulation by Wind and Water, 455. Dewey, Henry, Raised Beach of North Devon, 154. Dicynodont Reptiles, New Genera, 570. Distribution and Origin of Life in America, 128. Doelter, Professor Dr. C., Mineralogy, 321, 568. -Dollo, L., Annals of Congo Museum, 473. Douglas, J. A., Geological Section, Andes of Peru and Bolivia, 572. Dover Coal-field, 132. i Drift Deposits, North America and Europe, 14. Duddon Estuary, 135. ARTH, Structure of the, 37; its Shape, Size, Weight, and Spin, . 818; Age, 376. Earthquake, New Madrid, 224. Earthquakes, 274. Heypt, Geology of, Notes to Maps, 39. Geology of South-East, 266. Egyptian Eehinoids, Museum, Cairo, 315. Hlgee, Frank, Moorlands of North- East Yorkshire, 124. Elles, G. L., Relation of Rhiwlas and Bala Limestones, 519; Shelly and Graptolitic Faunas, British Ordo- vician, 520. Eminent Living Geologists: Dr. Kduard Suess, 1; James Geikie, 241. Hoanthropus Dawson, A. Smith Woodward, 4338. Eocene Beds, Hengistbury Head, 101. Foraminifera, Hants, 555. Koliths, Natural Home-made, 47. Hquisetites Stems, Oolite, Yorks, 3. Hquus capensis, 570. Eistheria, Bunter, South Shropshire, 518. Evans, Dr. J. W. (Death of H. K. Slater), 477. s79 HARNSIDHES, W. G., appointed to Sorby Chair, Sheffield, 432. Fiords, Nature and Origin of, 562. Fisher, Rev. O., Rigidity of Earth, 250; Origin of Mountains, 434. Flett, Dr. J. S., Geology of Lizard and Meneage, 309. Flint Implements of Early Man, 46. Flints, Sub-crag, 553. Flora and Fauna, Upper Keuper, Warwickshire and Worcestershire, 461. Flora of Marske Quarry, Yorks, 136. Floras, S. Staffordshire Coal-field, 462. Foraminifera, South California, 325. Eocene, Hampshire, 555. Fossil Beads, Bedfordshire, 138, 139, 190. Fossil Flora of Pembrokeshire Coal- field, 280. Fossil Plants, New Zealand (collected by D. G. Lillie), 231. Index. 579 Fossil Plants, Old Hill Marls, South Staffordshire Coal-field, 215. Fossilium Catalogus, F'. Frech’s, 317. Fossilization in Paleozoic Lycopods, 337. Fourtau, R., Egyptian Hchinoids, Cairo Museum, 315. Fraine, Dr. EH. de, Structure and Affinities of Swtcliffia, 316. Frech, F., Fossilium Catalogus, 317. Fritsch, Dr. A., Obituary of, 576. Frost,G.A.,Dapedius granulatus, 234. Fuller, L. Myron, New Madrid EHarth- quake, 224. ADOW, HANS, Wanderings of Animals, 423. Garabal Hill, Plutonic Rocks of, 499, 536. Garwood, EH. J., Calcareous Ales and Paleeozoic Rocks, 440, 490, 552. Gascony, The Landes of, 427. Geikie, Sir A., elected a Trustee of British Museum, 432. Geikie, Professor James, 241. Geological Congress, International, Toronto, 288, 486. Geological Exploration, N. Assam,474. Geological Museum, Jermyn Street, 89, 379. Geological Society, Edinburgh, 235. Glasgow, 276. — london, 40, 41, 42, 92, 94, 136, 137, 178, 180, 188, 189, 231, 233, 240, 278, 279, 282, 826, 328, 428, 429, 572; Annual General Meeting, 180. Geological Structure of West Corn- wall, 70. Geological Survey, British Columbia, 320. Canada, 178, 319, 320, 426. Egypt, 266, 312, 324, 425, 475. Great Britain, Memoirs, 88, 172, 174, 217, 309, 373, 466, 524. India, 167, 240, 268, 427. Towa, United States, 226. Ireland, 86, 129. New Zealand, 270. Queensland, 1338, 134. Rhodesia, 229, 417. F Scotland, Memoir, 129, 264. South Australia, 427. Transvaal, 176. United States, 129, 170, 177, 224, 312, 321, 325, 470, 471, 472, 528. — Victoria and Tasmania, 133. — Western Australia, 269, 473. —— Summary of Progress, 466. Fae 580 Geology and Forestry, 526. Gibson, Walcot, Concealed Coal-field of Yorks and Notts, 373. Glasgow Geological Society, 276. Goode, R. H., Fossil Flora of Pem- brokeshire Coal-field, 280. Granites, Fluting and Pitting of, 572. Graptolitic Faunas, British Ordovician, 520. Great Oolite, Crinoid Beds and place of Rhynchonella concinna, 459. Green, J. F. N., Duddon Estuary, 135. Green, Upfield, Geological Structure of Western Cornwall, 70. Gregory, J. W., Origin of Fiords, 562. Ground-water and Springs, 275. Guide to Collection of Gemstones, Museum Practical Geology, 89. Gwinnell, R. F., Obituary of, 191. ALESOWEN Sandstone Series, S. Staffordshire Coal-field, 281. Halle, Dr. T. G., Upright Hquwisetites Stems, 3; Mesozoic Flora of Graham Land, 216. Hamda Country (part of Sinai), 135. Hampstead Heath, Geology, ete., 374. Harlé, E., Landes, Gascony, 427. Haselhurst, 8. R., on Septaria, 288. Hatch, Dr. F. H., Rock Disintegra- tion, 40; Petrology, 271. President Institute Mining and Metallurgy, 528. Hawkins, H. L., Lanieria, 199; Lantern of Perischodomus, 300. Hayden, H. H., Minerals of India, 268. Heath, Charles E., Beginners’ Guide to the Microscope, 38. Heimhalt,H. H.von, Springs, etc., 275. Helminthochiton cequwivoca, Robson, sp. nov., 302. Hickling, G., Variation of Planorbis multiformis, 278. Hils Basin, Dr. A. von Koenen, 475. Himalayan Folding, Origin of, 167,532. Himalayas, Theory of, 250, 385, 434. Hinde, G. J., Solenopora Garwoodi, sp. nov., 289. Hobson, B., International Geological Congress, Canada, 486. Holectypoida, Lanieria, one of the,199. Holland, Sir T. H. Origin of Himalayan Folding, 167; Indian Desert Salt Deposits, 268. Holmes, A., Age of Earth, 376. Homalostega cavernosa, Brydone, sp. noy., 98. Vuleani, Brydone, sp. nov., 98. Hooley, R. W., The Skeleton of Ornithodesmus latidens, 180, 570. Index. Horwood, A. R., Upper Trias of Leicestershire, 21, 73, 109, 121; Leicestershire and South Derbyshire Coal-field, 381. Hull, Professor E., Norwegian Fjords, 9; Chart North Atlantic, 279. Hunt, A. R., Sea-water and Critical Temperatures, 95, 190, 284; Age of Torbay Raised Beaches, 106; Sub- merged Forest, Scotland, 475. Hutchinson, Sir J., Obituary of, 382. GNEOUS Rocks, Unsaturated, 508. Illing, V. C., Trilobites in Stocking- ford Shales, 452. India, Mineral Products of, 268. Indian Desert Salt Deposits, 268. Innes, D. E., U. Silurian Corals, 328. Interbasaltic Rocks N. Ireland, 86. International Geological Congress, Canada, 240, 486. Tridosmine in the Transvaal, 230. Iron-ore Deposits, California, 471. Tron-ores of Tennessee, 134. Irving, A., Buried River Channel, Fletton, near Peterborough, 414. Ivybridge and Modbury, Geology, 217. Saturated and ACKSON, J. W., Lynx in North Wales and Derbyshire, 259. Johnston-Lavis, H. J., Sea-water and Critical Temperatures, 143, 239. Jones, O. T., Abereiddy Bay and Pencaer, Pembroke, 465; Pillow Lavas, N. and S. Wales, 516. Jowett, A., Volcanic Rocks, Forfar- shire, 329. Jubilee of GEOLOGICAL MAGAZINE, 1914, 289. Judd, Professor J. W., elected Emeritus Prof. Geology, 432. Jukes-Browne, A. J., Chalk-pebbles, English Channel, 62; Division of Upper Chalk, 163, 431; Torbay Raised Beaches, 236; The Term “Charmouthian ’, 475. Jura, The Bernese, 427. Jurassic Ammonites, Tunis, 232. ARROO System of South Africa, Beaufort Beds of, 388. Kay, George F., Underground Water Resources of Iowa, 226. Kay, H., Halesowen Sandstone, 281; Streams, Black Country, 457. ‘Kelloway Rock’ of Scarborough, 231. Kendall, Prof. P. F., Stratigraphy of, Hquisetum Beds, 7. Inden. Kendall, P. F., jun., Lecturer to Wye, 432. Kent Coal-field, 576. Keuper Marls around Charnwood, 90. Kindle, E. M., Lycopod Stems, 337. King, W. W., & W. J. Lewis, Carboni- ferous Beds, Lye, Staffordshire, 521. Kinta, Malay States, Geology of, 223. appointed AMPLUGH, G. W., Age of Raised Beaches, 238. Land of Deep Corrosions, 148. Lang, W. D., Lower Pliensbachian, “ Carixian,’ 401. Lameria, Duncan, and note on Echinoid Evolution, 199. - Lantern of Perischodomus, 300. Lapworth, Professor C., Retirement of, 384. Leicester Coal-field, 456. Lias Ironstone, South Warwickshire and Oxfordshire, 460. Liesegang, RR. E., Diffusionen, 469. Lizard and Meneage, Geology of, 309. Lobley, J. Logan, Obituary of, 384. London Wells, Records of, 174. Lophophyllum and Cyathaxoma, 49. Lost Towns of Yorkshire Coast, 126. Lower Paleozoic Rocks, Yorks, 41. Lynx in N. Wales and Derbyshire, 259. _Lystrosaurus, Limbs of, 256. Geologische & ACKENZIE, G. C., Magnetic Tron-sands, 426. McLintock, W. F. P., Guide to Gem- stones in Museum of Geology, 89. . Maenetic Iron-sands, Quebec, 426. Maitland, A. Gibb, Permo-Carboni- ferous Ice Age, 427. Malay Peninsula, History of, 92. Manus of Trachodon, 379. March, M. Colley, Structure and Relationships of Carbonicole, 279. Marine Reptilia, Oxford Clay, De- seriptive Catalogue, pt. ii, 219. Marr, J. H., Lu. Paleozoic Rocks, 47. Marshall, P., The ‘ Cretaceo-Tertiary ’ of New Zealand, 286. Martin, G. C., Geology and Coal-fields of Alaska, 225. Matley, C. A., Geology of Bardsey Island, 188. . Mawson, J., Cretaceous of Bahia, 356. Meachem, F. G., Development of Midland Coal-field, 522. Membranipora edificata, Brydone, sp. nov., 198; M. cervicornis, Bry- done, sp. nov., 198; MW. Gravensis, Brydone, sp. noy.,197; M. plicatella, 581 Brydone, sp. nov., 198; M. Sparksi, Brydone, sp. nov., 197. Mennell, F. P., A Manual of Petro- logy, 375. Merostomata, Position of the, 293. Merrill, G. P., Meteoric Iron, 229. Merwin, H. E., Liquids of High Refraction, 276. Mesozoic Flora of Graham Land, 216. Metamorphosed Sediments, British East Africa, 329. Meteoric Iron, Missouri, 229. Meteoric Stone, Kansas, 277. Micraster precursor, Rowe, 430. Micropholis Stowi, Huxley, 340. Microscope, Beginner’s Guide, 38. Model for Polarizing, 447. Microscopical Petrography, 135. Mill, H. R., Physiography, 566. Milne, Prof. John, Obituary of, 432. Mineral Kingdom, 565. Mineralogical Society, 44, 45, 135, 236, 330. Mineralogy, Dana’s Manual, 38. Determinative, with Tables, 470. — Handbook, 568. Phillips’, A. H., 272. Mines Department, Canada, 130. Union of South Africa, 176. Mines and Mining, Lake District, 468. Mining in Elko County, Nevada, 134 ; in South Australia, 427. Mining and Metallurgy, 324. Miocene Beds, Victoria Nyanza, 428. Miocene Fauna, Eggenburg, 325. Mockler, F. J., Obituary, 240. Moir, J. Reid, Flint Implements of Karly Man, 46; Striations upon Flint, 416; Sub-crag Flints, 553. Monckton, G. F., A Human Skeleton, British Columbia, 364. Monckton, Dr. H. W., Hafslo Lake, Norway, 40. Monticuliporoids, Development and Systematic Position of, 32. Moorlands, North-East Yorkshire, 124. Mount Lyell Copper District, Tasmania, 571. Mountains, the Origin of, 385. Moysey, L., Paleoxyris and Veta- capsula, 458. Mucronella (?) Spenceri, sp. nov., 97. Murray, G. W., The Hamada Country, 135. Brydone, EPHELINE in Phonolite Dykes, IN’ Omeo, 319. New Zealand, Geological Survey, 270. Younger Formations of, 438. 582 Newton, R. Bullen, Cainozoic Mollusca from South Africa, 177. Newton, W. M., Figures in Flint, 424, Newton Abbot, Geology of, 524. Nickel Industry, 567. North, F.J., The genus Syringothyris, 393. Northern Peru, Geology of, 233. Norway, Hafslo Lake, ete., 40. Norwegian Fjords, Physical History, 9. BITUARY: Tempest Anderson, 478; Baron Avebury, 334; Sir George H. Darwin, 477; W. Fox, 336)) Dr As Britseh, 576). Bey BY Gwinnell, 191; Sir Jonathan Hutchinson, 382; T. F. Jamieson, 332; EH. A. L. Kittl, 336; J. Logan Lobley, 384; Professor John Milne, 432; F.J. Méckler, 240; Dr. H. F. Parsons,575; Dr. M. Poignand, 191; Dr. P. Lutley Sclater, 382; H. K. Slater, 336; W. H. Sutcliffe, 479; Dr. H. Ramsay Traquair, 47; L. F. Ward, 336 ; Ellen S. Woodward, 96. Odling, M., Bathonian, Oxford, 282. Oil-shales of the Lothians, 129. Old Hill Marls, South Staffordshire Coal-field, Fossil Plants, 215. Oldham, R. D., the Himalayas, 532. Ore-deposit, Dolores Mine, Mexico, 91. Origin of Mountains, O. Fisher, 435. Ornithodesmus latidens, 180, 570. Oswald, Dr. F., Caucasus, 559. PA CHYGENELUS monus, Wat- son, gen. et sp. nov., 145. Paleolithic Figures in Flint, 424. « Human Skull, Piltdown, Sussex, 42. Man in Jersey, 92. Paleoxyris vetacapsula, etc., 453. Palzozoie Coral-reefs, 227. —— Lycopod Stems, 337. and Newer Rocks, Folding, 463. — Rocks and Caleareous Alge, 440, 552. Sediments, 325. Paleozoology, Professor Reichenbach’s Textbook, 37. Paradoxides, two Species of, in Shropshire, 42. Park, Professor J., Younger Forma- tions, New Zealand, 438. Parkinson, J., Metamorphosed Sedi- ments, East Africa, 329. Parks, Dr. W. B., Building and Orna- mental Stones of Canada, 178. Parsons, Dr. H. F., Obituary of, 575. Index. Peile, Major A. J., Geology of Bermuda Islands, 413. “Pennant Collection’ of Fossils, 192. Perischodomus, Lantern of, 300. Permian of Durham, 135. Permo-Carboniferous Ice Age, Western Australia, 427. Petrology of Arran, 305. Kalgoorlie Goldfield, Western Australia, 283. Petrology, F. P. Mennell’s, 375. Textbook of, 271. Phillips, A. H., Mineralogy, 272. Phosphates of Egypt, 425. Physiography, Outlines of, 566. Picrite of Foel lwyd, Carnarvon, 108. Pillow Lavas, N. and 8. Wales, 516. Piltdown Man, the, 433. Planorbis multiformis, Variation of, 278. Plant-petrifactions in Chert, 524. Pleistocene Geology of New York, 379. Pliensbachian, Lower, ‘Carixian,’ 401. Plutonic Rocks, Garabal Hill, 499,536. Poignand, Malcolm, Obituary of, 191. Polarizing Microscope, Model, 447. Polyzoa, Chalk, 436. Portheus molossus, Cope, Kansas, 529. Postlethwaite, J., Mines and Mining, Lake District, 468. Poynting, J. H., The Earth, Shape, Size, Weight, and Spin, 318. Primitive Man, Origin of, 39. Psalidocrinus, new genus from the Tithonian, Stamberg, 346. remesi, Bather, sp. nov., 352. UARTZ Crystals, Belgium, 571. Queensland, Mines of, 134. AASAY, Geology of, Horace B. Woodward, 235. Iron-ore, W. Thornycroft, 235. Rain and Rivers, the Work of, 36. Raised Beach of North Devon, 154. Raised Beaches, Age of, 238. Rastall, R. H., Minerals of Barrington Bone-bed, 252; Petrology, 271. Raw, F., Wind-worn Stones, Salop, 523. Reed, F. R. Cowper, Eocene Beds, 101. Reichenbach, Professor E. §S. von, Textbook Paleozoology, 37. Reid, Clement, Retirement, 96; The Geology of Dartmoor, 172; Sub- mereed Forests, 370. RemeS, Dr. Mauric, New Crinoid, 346. Rhamphorhynchus Gemmingi, 570. Rhiwlas and Bala Limestones, Bala, 519. Index. Rhodes, J. E. Wynfield, Picrite of Foel lwyd, 108. Rhodesia, Tenth Annual Report of Museum, 134. — Southern, Report of Survey, 229. Rigidity of the Earth, 250. River Valleys, Submerged, 262. Road-metal, 379. Robinson, W.N., Geological Structure, N. Caucasus, 559. Robson, G. C., Helminthochiton @quiwoca, sp. nov., 302. Rochdalia Parkeri, H. Woodw., gen. et sp.noy., Coal-M., Rochdale, 352. Rock Disintegration, 40. Royal Society, 192, 230, 325. Russell, E. J., Soils, Harpenden, 278. Q\ALFELD, Dr. H., Upper Jurassic Strata, England, 328. Saturated and Unsaturated Igneous Rocks, 508. Scharff, R. F. Dr., Distribution and Origin of Life in America, 128. Scherer, J., Earthquakes, 274. Schlee, Dr. P., The Bernese Jura, 427. Schwarz, EH. H. L., South African | Cretaceous Dinosaurs, 263. Sclater, P. Lutley, Obituary of, 382. Scott, A., Plutonic Rocks, Garabal Hill, 499, 536. Serivenor, J. B., Geology of Kinta District, 223; Geological History, Malay Peninsula, 92. Sea-water and Critical Temperatures, 96, 143, 190, 239, 284. Semieschara labiatula, sp. noy., 248; S. mundesleiensis, Brydone, sp. noy., 249; S. occlusa, Brydone, sp. nov., 249. Septaria: the ‘Shrinkage’ view, 514. Septarian Structure, 99, 288, 361. Shand, §. J., Saturated and Un- saturated Igneous Rocks, 508. Sheppard, T., Lost Towns of York- shire Coast, 126. elected President Yorkshire Naturalists for 1914, 528. Sherborn, C. Davies, Geological Structure of Western Cornwall, 70. Sibly, Dr. T. H., appointed Professor of Geology, Cardiff, 528. Sinai: Gebel Hamm4én Farin, 324. Sinel, J., Paleolithic Man, Jersey, 92. Skeats, E. W., Nepheline, Omeo, 319. Skeleton, Human, B. Columbia, 364. Smith, Stanley, Awlophyllwm, 41. Smith, W. Campbell, Flora and Fauna, Upper Keuper of Warwick- shire and Worcestershire, 461. Brydone,. 583 Soils and Substrata, Geology of, 127. Solenopora Garwoodi, sp. noy., 289. South African Dinosaurs, 263. Spath, Leonard F., Jurassic Ammo- nites, Tunis, 232. Spencer, L. J., World’s Minerals, 565. Spencer, W. K., Evolution of Cre- taceous Asteroidea, 230. Sphenophyllum in Australia, 133. Spilite Lavas and Radiolarian Rocks, New South Wales, 17. Spirorbis Limestones, North Warwick- shire, 463. ; Spurr, J. E., Ore-deposits, Dolores Mine, Mexico, 91. Steel, D., Termites and Geology, 427. Steuart, D. R., Oil-shales, 129. Stockingford Shales, Nuneaton, 452. Stone, R. W., Coal near ‘ Black Hills’, Wyoming, 225. Stopes, Dr. M. C., Plant Petrifactions in Chert, 524. Strahan, Aubrey, 288, 488; appointed Director Geol. Sury., 576. Strathspey and Atholl, Geology of 264. Stratigraphical Position of Beds with Equisetum, 7. Stratigraphy of Chalk of Hants, 122. of North America, Index to, 170. Stream-courses of Black Country Plateau, 457. Striations on Flint, 416. Sub-crag Flints, 553. Submerged Forests, 370; in South- West Scotland, - 475. River-valleys, 262. Suess, Dr. Eduard (life and portrait) ,1. Suffolk Valleys, Age of, 327. Sulphur-mines in Sicily, 323. Sutcliffe, W. H., Obituary of, 479. Sutclifia, Structure and ffinities, 316. Syncline, Loch Awe, 189. Syringothyris, Winchell, 393. eee Bear, 571. Temnospondylous Amphibian, South Africa, 340. Tennessee, Resources of, 324. Termites and Geology, 427. Tetrapoda, Skull Hlements of, 571. Texas, Southern, Semi-Arid Condi- tions, 481. Thomas, H.H., Fossil Flora, Yorks,136. Thompson, Beeby, Northern Peru,233. Thompson, Charles, Derived Cephalo- poda, Holderness Drift, 137. Thomson, J. A., Kalgoorlie Gold-field, 283. Thornycroft, W., Raasay Iron-ore, 235. 584 Todd, J. H.; 361. Torbay Raised Beaches, 106, 236. Traquair, Dr. R. H., Obituary of, 47. Trechmann, C. Taylor, Anhydrite in Magnesian Limestone, 94. Trilobite Fauna, Shropshire, 42. Trilobites, Stockingford Shales, 452. Tyrrell, G.W., Petrology of Arran, 305. Septarian Structure, NDERGROUND Water Resources of lowa, 226; of Poitou, 229. United States Geol. Survey, 321, 528. Upper Chalk, Division of the, 163. Proposed Recognition of Two Stages in the, 56. Upper Jurassic Strata, England, 328. Upper Silurian Rugose Corals, from Grindrod Collection, 328. Upper Trias of Leicester, 21, 73, 109. Ussher, W. A. E., Geology of Ivy- bridge and Modbury, 217; Geology, Newton Abbot, 524. ERNON, BR. D., Leicester Coal-field, 456.” Verruca prisca, Chalk, Norwich, 103. Vertebrata, South African, 378. Victoria, Tasmania, Geology, 133. Volcanic Rocks, Forfarshire, 329. Volcanoes, Structure of, 273. Volney, Lewis J., Determinative Mineralogy with Tables, 470. YALCOTT, C. D., Cambrian Brachiopoda, 312. Walford, EK. A., Great Oolite Crinoid Beds and Rhynchonella concinna, 459; Lias Ironstone, Warwickshire and Oxfordshire, 460. Walther, J., Desert Conditions, 132. Wanderings of Animals, Gadow’s, 423. Ward, F. Kingdon, The Land of Deep Corrosions, 148. Water-supply Papers of the U.S.A. Geological Survey, 177, 472. Watson, D. M. S., A Cynodont from Stormberg, 145; Limbs of Lystro- saurus, 256; Micropholis Stowi, Index. South Africa, 340; Beaufort Beds, South Africa, 388. Welsch, J., Underground Waters, 229. Western Australia Geol. Survey, 269. White, H. G. Osborne, Geology of Winchester and Stockbridge, 88. Willis, Bailey, Index to the Strati- graphy of North America, 170. Wills, L. J., Flora and Fauna, Upper Keuper, Warwickshire and Worcestershire, 461. Winchester and Stockbridge, Geology of, 88. Wind- worn Rocks, Hill, Salop, 523. Withers, T. H., Verruca prisca, Norwich Chalk, 103. Wittenburg, Trias, Caucasus, 559. Woods, Henry, Cretaceous Lamelli- branchia, 228. Woodward, Dr. A. S., Hoanthropus Dawsoni, 42, 433 ; Portheus molossus, Cope, Kansas, 529. Woodward, Ellen Sophia, Obituary of, 96. Woodward, Dr. H., Position of Mero- stomata, 293; Rochdalia Parkeri, Coal-measures, Rochdale,352 ; Cara- docian Cystoidea, 418. Woodward, H. B., Geology of Soils and Substrata, 127; Geology of Raasay, 235; Geological Atlas, 424. Woolacott, Dr., Permian of Durham, 135. World’s Minerals, 565. Wright, Dr. F. E., Microscopical Petrography, 135; Illumination of Petrological Microscope, 277. Wyllie, B. K. M., Plutonic Rocks of Garabal Hill, 499, 536. Wyoming Geology, 134. etc., Lilleshall AKOWLEW, N., Paleozoic Coral- reefs, 227. Yorkshire Philosophical Society, 378. INC - BLENDE Limonite, 428. 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