pe Lnftnttiactha tne tbe tno nfo Minto ant ohn teen beri tacecih ened tafe tectha ie fe toateiny che Garepavniconaieemen tt 1 ayer mn Ay He SpdlpesiptantinceLicetinateubeeeae eaten Ey eaebetb ane et ty a A eat Pain hai Snap teita’ etait eR aleemnke eae t THE GEOLOGICAL MAGAZINE. NEW SERIES. DECADE IV. VOL. X. JANUARY—DECEMBER, 1903. att 24 Peay Wee °s AS a Hives 7) SUA GEOLOGICAL MAGAZINE Monthly Jounal of Geologn: WITH WHICH IS INCORPORATED “THE GEOLOGIST.” NOS. CCCCLXIII TO CCCCLXXIV. EDITED BY HENRY WOODWARD, LL.D., F.R.S., Pres. R.M.S., F.G.S., LATE OF THE BRITISH MUSEUM OF NATURAL HISTORY 5 PRESIDENT OF THE PALHONTOGRAPHICAL SOCIETY, VICE-PRESIDENT OF THE ZOOLOGICAL AND MALACOLOGICAL SOCIETIES ; MEMBER OF THE LYCEUM OF NATURAL HISTORY, NEW YORK; AND OF THE AMERICAN PHILOSOPHICAL SOCIETY, PHILADELPHIA; HONORARY MEMBER OF THE YORKSAIRE PHILOSOPHICAL SOCIETY; OF THE GEOLOGISTS’ ASSOCIATION, LONDON; OF THE INSTITUTION OF MINING AND * METALLURGY, LONDON; OF THE GEOLOGICAL SOCIETIES OF EDINBURGH, GLASGOW, HALIFAX, LIVERPOOL, AND SOUTH AFRICA; CORRESPONDING MEMBER OF THE GEOLOGICAL SOCIETY OF BELGIUM; OF THE IMPERIAL SOCIETY OF NATURAL HISTORY OF MOSCOW; OF THE NATURAL HISTORY SOCIETY OF MONTREAL; AND OF THE MALACOLOGICAL SOCIETY OF BELGIUM. ASSISTED BY ROBERT ETHERIDGE, F.R.S. L.&E., F.GS., F.C.S8., &e. WILFRID H. HUDLESTON, M.A., F.R.S., F.G.S., F.LS., F.C.8. GEORGE J. HINDE, Px.D., F.BS., F.G.S., &e. AND HORACE BOLINGBROKE WOODWARD, F.R.S., F.G.S., &c. NEW SERIES. DECADE IV. VOL. X. JANUARY—DECEMBER, 19038. LONDON: MESSRS. DULAU & CO., 37, SOHO SQUARE, W. 1903. SATIN Ree Gi oe ea LER REORD Cian uit g i | PRINTED BY STEPHEN AUSTIN AND SONS. SOM EATEN AN eT Tei eo See OLS OL ee EAM HEN pate LIST OF PLATES. Some Wenlock Species of Lichas Professor Albert Gaudry Flint Implements from the Fayim, Egypt Flint Implements from the Fayim, Egypt Fossil Prawns, etc., from the Isle of Wight Eoliths from South-West Hants Koliths from South-West Hants Map showing the course of the Avon below Downton A giant Cirripede from New Zealand A giant Cirripede from New Zealand Shells and Concretions from Creechbarrow Barranca de las Calaveras, Concud, Spain . Sections at Strathy Point and Kinbrace Royal Bohemian Museum, Prague Beer Head, from the West .. . Under Hooken and Hooken Cliff Markings on Quartzite Slabs from Canada . Photograph of the newly discovered Mammoth River Curves . Carboniferous Sandstone at Muckros Head Memorial Tablet to Professor H. A. Nicholson Palxozoic Nautiloidea from North China Profile of Skull of Arsinditherium Zitteli, Beadn. Front view of Skull of Arsinditheriwm Zitteli, Beadn. . FACING PAGE 12 49 LIST OF ILLUSTRATIONS IN THE TEXT. Section of Deposit of large Detritus at a River’s Mouth Distribution on Sea-bottom of Vertical Sheet of Sediment . Homalonotus Barratti, H. Woodw., sp. nov. . Map of the Northern part of the Fayim Submarine Contour-lines from Ireland to Portugal Section showing the succession of the Osborne Series . River Meanders Creechbarrow from the north-east Manganese nodule from Creechbarrow Part of a calcareous nodule Brachymetopus Strzeleckii, McCoy Pisolitic limestone showing two faces Triangular Flint Implement from Herne Bay . Shoe-shaped implement from Northfleet Chert implement with curved edges Chopping tool, province of Poitou Axe-head with hollowed edge, Denmark Flint chisel, Denmark Chipped knife of chert, Egypt Flint knife, Denmark 3 Unground axe-head, Hitcham, Bucks Flint javelin-head from long barrow, Wilts Anthracosiro woodwardi, R. I. Pocock, gen. et sp. nov. Section at Wockley Burrows on quartzite slab Olenellus *Thompsoni, Hall Isochiline at ea Post-Glacial Section at Dundee Upper Dentition of Megalohyraaz eocenus, Andrews, gen. et sp. nov. Right ramus of Mandible of Pterodon africanus, Andrews, sp. nov. Restoration of Palate of Scylacosaurus Sclateri, Broom, gen. et sp. nov. Lower Jaw of Karoomys Browni, Broom, gen. et sp. nov. Palatal view of Skull of Hyperodapedon Gordoni, Huxley 146, 147 Vill List of Illustrations in the Text. Dorsal aspect of Skull of Stenometopon Taylori, Boulenger, gen. et sp. noy. Matheria brevis, Whiteaves, sp.nov. . . . ... - Section of Cutting at Charmouth. . .....2.. =. Anthracosiro fritschit, Pocock, sp. nov. G6 Section of the Alluvium of the River Thames, Bermondsey Longitudinal section of Actinoceras docens, Barr., sp. nov. . Actinoceras imbricatum, Hisinger, sp. . - . . - « « Goniocenasvancep stl all Si essr- sew iNoutcu-noin a= nnnrnr Listraeanthus Wardi and Petrodus acutus, A. 8S. Woodw. . ivpostomayot Bronteus 2). 9. Skull of Batrachosuchus Browni, Broom, sp.nov. . PAGE 356 358 390 406 456 482 483 484 487 490 500 THE GHOLOGICAL MAGAZINE. NEW SERIES. \IDIEGAIDE MIN. > WOES XG No. I.—JANUARY, 1903. QR IFES PEIN( AGI, RASS aD IO sa. —— I.—Somz SuecEstions on Exrinorion. By C. W. Anprews, D.Sc., F.G.S., British Museum (Natural History). ee sudden disappearance of groups of animals, which have existed through long periods of time and have attained a high degree of specialization, is a phenomenon of which many instances will occur to every student of Palzozoology. For instance, to mention only two cases in illustration, we may refer to the disap- pearance of the Dinosaurs at the end of the Secondary period, and that of the North American Titanotheres in the Miocene. Of the proximate causes of this extinction little is known: they must have been either inherent in the organisms themselves, or have been connected with the relations of the organisms with their environ- ment; probably in every case several factors co-operated to bring about the observed result. In a recent paper by Mr. C. B. Crampton (Proc. Roy. Phys. Soc. Edinburgh, vol. xiv, p. 461) a possible inherent cause of extinction is suggested. It is impossible to do justice to this interesting paper in a short note, but the gist of the argument seems to be as follows:—In the original unicellular organism the possibilities of variation are almost infinite, but as soon as evolution along any line begins, these possibilities are restricted, and become more and more so the more highly specialized the animal is; in short, the potential variation of an organism becomes less and less as specialization advances. Furthermore, under the influence of natural selection, in each generation the individuals which tend to vary in the same direction will survive, while at the same time, as already pointed out, their capacity for variation becomes more and more restricted. The consequence of this will be that the more highly specialized any stock becomes, the more the individuals composing it will come to resemble one another, until at length the same results as arise from close inter- breeding, viz., weakening of the stock and, finally, extinction, may follow. In a paper recently read before the Zoological Society, the present writer, in speaking of the evolution of the Proboscidea, took the DECADE IV.—VOL. X.—NO. I. 1 2 F. R. Cowper Reed—Some Wenlock Species of Lichas. opportunity of pointing out another possible cause of extinction of some groups of animals. It will be observed that in many cases the evolution of a group of animals is accompanied by a simultaneous increase in the bulk of the individuals composing it. The Proboscidea themselves offer a fairly good instance of this tendency, but a better known case is that of the horses. An almost necessary corollary of this increase in bulk is the lengthening of the individual life, or at least what, for our argument, amounts to much the same thing, the lengthening of the time taken to attain sexual maturity. In many Ungulates this increased longevity is indicated by various modi- fications of the teeth, tending to give them a longer period of wear: generally this end is attained by the increasing hypselodonty of the cheek-teeth. A necessary consequence of the longer individual life will be that in a given period fewer generations will succeed one another, and the rate of evolution of the stock will therefore be lowered in the same proportion. If now the conditions of life undergo change, the question whether a given group of animals wiil survive or become extinct will depend upon whether it can undergo sufficiently rapid variation to enable it to avoid getting so far out of harmony with its surroundings that further existence becomes impossible. It seems to follow then that the smaller animals, in which the generations succeed one another rapidly, will have a better chance of surviving than the larger and more slowly breeding forms, which at the same time will be still further handicapped if, as is usually the case, they are more highly specialized than the smaller forms, and therefore have a more restricted range of possible variation. Another result of the increased length of the individual life would be that, during the earlier history of a stock the modification under- gone by its members would be more rapid than among the later forms, a phenomenon of which actual instances might be cited, e.g. in the Proboscidea. On the same principle it may perhaps also be explained why certain groups have remained comparatively unchanged through long periods of time. The Sirenia may be a case in point, though no doubt in this case, among other factors, the comparative stability of the conditions of life has had much to do with the conservative character of the group. JI.—Woopwarpian Musrum Norres: On some Wentock SPECIES oF LIcHAs. By F. R. Cowrrer Rezep, M.A., F.G.S. (PLATE I.) ({\HE entire collection of Wenlock fossils made by T. W. Fletcher, Hsq., which is now in the Woodwardian Museum, affords unsurpassed facilities for studying the material on which a large number of species of trilobites were founded. Particularly is this the case with those of the genus Lichas, and a recent examination of the types and other specimens which Fletcher used in writing his paper ‘Observations on Dudley Trilobites” (Q.J.G.S., 1850, F. R. Cowper Reed—Some Wenlock Species of Lichas. 3 vol. vi, pp. 235-239, pls. xxvii and xxvii bis) has led me to make the following notes upon them. I have also had the privilege, through the kindness of Dr. Arthur Smith Woodward, F.R.S., of examining the specimens in the British Museum (Nat. Hist.), Cromwell Road. Licuas (CorypocEePHaLus) ANGLIcUS (Beyrich). (Pl, I, Figs. 1, 2.) Lichas Bucklandi, Fletcher (pars): Q.J.G.S., 1850, vol. vi, p. 235, pl. xxvii, figs. 2, 3, 4, ?5, 5a (non figs. 1, 1a); pl. xxvii dis, figs. 1, la, 10. There is considerable variation in the degree of development of the spines on the pygidial margin of this species. A similar variation is noticeable in Cheirurus bimucronatus and the species of Acidaspis from the same beds. The relative length of the axis of the pygidium also shows marked individual differences. Fletcher figured one specimen (op. cit., pl. xxvii, figs. 5, 5a) which he described as a young individual, and probably it should be regarded as such. But there are two well-marked and constant varieties which show definite features separating them from the type-form, and in fact are more abundant than the latter. (i) The first variety, which may be called wenlockensis (Pl. 1, Fig. 1), has a pygidium which is subquadrate in outline, and has almost a straight posterior border. ‘The nine marginal spines are unequally developed ; the first two pairs are strong and of equal size, but the third pair, situated at the lateral corners of the posterior margin, are much stouter and larger, projecting nearly straight backwards behind the pygidium. Between them lie three equidistant smaller spines, the median one of which is generally the largest. Minute prickles are in some specimens noticeable along the margin between the spines. A shallow groove parallel to the posterior edge of the pygidium and marking off a distinct border, but not crossing the post-axial median piece, is present on the lateral lobes behind the second pair of pleure. A similar though fainter groove is distinguishable on the pygidium of the type-specimen and type-form fioured by Fletcher (op. cit., pl. xxvii bis, figs. 1, 1a), and in the other specimen regarded by him as a young individual (pl. xxvii, figs. 5, 5a), but no mention of it is made in his description. The posterior half of each of the two pairs of pleurz behind the pleural furrow in the variety wenlockensis is also remarkably narrow in comparison with the anterior portion. In Fletcher’s figure of the type-form the posterior portion is made broader than it is in reality in the specimen. From the above remarks it will be seen that the distinguishing features of this variety are the general shape of the pygidium and the development of the lateral spines. The thorax and head-shield in complete specimens show no points of difference from the type- form which can be established as constant. (ii) The second variety (Pl. I, Fig. 2), of which there are also complete specimens in the Woodwardian Museum, likewise exhibits its distinctive features only in the pygidium. In this form there are only eight marginal spines, the posterior median one being absent or merely represented by a small prickle. The shape of the pygidium 4 F. R. Cowper Reed—Some Wenlock Species of Lichas. is subquadrate rather than semicircular ; the first two pairs of lateral spines (i.e. the pleural points) are moderately developed, and equal or subequal in size; the third pair of spines is developed as in the variety wenlockensis, being stronger and stouter than the others; the fourth pair of spines is reduced in size, and slender, and usually rather closely placed to the third pair, leaving the median portion of the posterior margin free of spines and only armed with small prickles. In other respects this variety resembles that above described. Both differ from the type-form by the subquadrate rather than semicircular shape of the pygidium, and by the specially strong development of the third pair of marginal spines. This second variety may be termed obtusicaudatus. Salter attributed both these varieties of Z. anglicus to L. hirsutus, as his labels and Catalogue show (Cat. Camb. Sil. Foss. Woodw. Mus., p- 130, a 961, a 968, a 964), but they differ completely from it, as a reference to Fletcher’s figured specimens and the descriptions of that species at once proves. ' The ‘angularity ’ of the head-shield upon which Fletcher remarks in one specimen (figs. 3, 3a, pl. xxvii) is caused by the sudden bend in the front margin of the free cheek, just outside the point where the facial suture cuts the border. This projection of the middle portion of the head-shield is very well marked in some specimens of the type-form and in the variety wenlockensis, and is indicated in the restoration of the front border by Fletcher (op. cié., pl. xxvii bis, fig. la). It appears to be a characteristic and constant feature, being noticeable wherever that portion of the head-shield is preserved. Licuas (CoRYDOCEPHALUS) HirsuTUS (Fletcher). (Pl. I, Figs. 3, 4, 5.) L. hirsutus, Fletcher (pars): Q.J.G.S., 1850, vol. vi, p. 236, pl. xxvii, figs. 6, 6a ; pl. xxvii dzs, figs. 2, 2a (mon pl. xxvui, figs. 7, 7a). L. Bucklandi, Fletcher (pars): ibid., pl. xxvii, figs. 1, la, 1b (mon cet.). There are three specimens ascribed to this species by Fletcher and figured by him, all of which are in the Woodwardian Museum. Excluding the remarks on the specimen figured on pl. xxvii, figs. 7, Ta, the description of the species given by Fletcher is fairly accurate and complete so far as it goes, but the figures (pl. xxvii, figs. 6, 6a; pl. xxvii bis, figs. 2, 2a) show such differences that they might be thought to represent distinct species. The specimens, however, from which these figures were drawn are in reality closely similar, and do not exhibit more than the customary amount of variation- The specimen on which figs. 6, 6a, pl. xxvii were founded is so imperfect that it shows Fletcher used other specimens together with it in order to draw up his description of the species. There is no distinctly raised border round the pygidium, the appearance in Fletcher’s figured specimen (pl. xxvii, fig. 6a) being due to unequal crushing. Other specimens show that the relative length of the axis slightly varies, and also the number of tubercular rings upon it. A well-preserved complete specimen in the Woodwardian Museum showing head, thorax, and pygidium attached, and several other less F. R. Cowper Reed—Some Wenlock Species of Lichas. 9) perfect specimens, enable me to give a complete description of the species, and render possible the identification of isolated head-shields, previously of doubtful specific position. Draenosis.—Head-shield broadly parabolic, more than twice as broad as long, swollen centrally, bent down at sides and strongly in front. Glabella elevated, convex, large, broader than long; greatest width across middle third. Central lobe long, subcylindrical with parallel sides between anterior bicomposite lateral lobes, slightly expanded in front, embracing front end of these lobes; defined pos- teriorly by strong curved transverse furrow at level of second lateral furrow. Anterior lateral lobes rather swollen, oval but slightly pointed behind ; each as broad as central lobe; extend three-fourths the length of the glabella; are defined externally by strong furrow. Middle and basal lobes obsolete, their place being occupied by a sub- triangular, uniformly swollen surface, not differentiated or marked off from the fixed cheek, except behind the eye, where the posterior portion of the axal furrow is faintly developed. Between the central lobe and neck-ring is a narrow post-central lobe depressed below the level of the central and lateral lobes, and defined laterally by the weak backward continuation of the first lateral furrows to the neck-ring; three conspicuous large isolated tubercles usually ornament it. First lateral furrows curve inwards strongly from anterior point of origin, sweeping round front end of anterior lateral lobes ; then run backwards to transverse furrow with increasing strength and almost parallel to each other, behind which they diverge and are feebly continued to neck-ring. Axal furrows strong, curved outwards, defining outer border of anterior lateral lobes; not continued behind second lateral furrows, which at level of eyes pass imperceptibly into them. Close to the neck-ring a faint furrow on each side represents the posterior portion of the axal furrows. Second lateral furrows form a continuation inwards of the axal furrows round the base of the anterior lateral lobes, joining first lateral furrows at angle of 75°-90°. Transverse central furrow runs across middle of glabella as continuation of second lateral furrows with equal strength, but with independent backward curva- ture. Occipital ring arched forwards, swollen, broadest in middle, generally with median tubercle. Fixed cheeks triangular, swollen towards inner portion, not marked off in middle from glabella; posterior edge straight, hori- zontal at right angles to axis of glabella, but bending sharply forward at outer angle at about 130°. LHye-lobe moderate, prominent, horizontal, at level of second lateral furrow. Neck-ring on posterior margin elevated, narrow, ornamented with single row of large tubercles. Facial suture makes a sharp bend outwards behind eye, curving thence backwards to cut lateral margin behind spine. Free cheek narrow, elongated, triangular, inner portion swollen, bearing prominent elevated eye of moderate size. Middle of lateral 6 fF. R. Cowper Reed—Some Wenlock Species of Lichas. margin furnished with strong short outwardly projecting spine, curving slightly backwards. Head-shield in all parts (including spines) ornamented with large tubercles, not closely set, with smaller ones interspersed. Thorax composed of eleven segments. Axis moderately convex, nearly as wide as pleural portions, cylindrical for first six or seven rings, then tapering gradually backwards to pygidium. Axal furrows well-marked. Axial rings narrow, rounded, with narrow articulating band. Pleuree narrow, rounded, cylindrical, with free pointed extremities ;. horizontally extended to fulcrum, which is situated at about half their length, then bent downwards and slightly backwards. Narrow flattened band on front edge. Hach thoracic segment bears a single row of a few large equally-spaced tubercles. Pygidium broadly parabolic, usually slightly broader than long. Axis convex, subcylindrical or slightly tapering, bluntly rounded at posterior end; extends about two-thirds the length of pygidium, and occupies about the middle third of width. One strong complete axial ring at front end with narrow articulating band on front edge, followed by 8-5 narrow transverse rows of tubercles in middle portion of axis; the first one or two rows are separated by more or less distinct furrows. Posterior end of axis abrupt, blunt, not circumscribed by furrow, but continued posteriorly by narrow, depressed, tapering post-axial median piece, which becomes parallel- sided and extends to posterior border between third pair of marginal spines. Lateral lobes flattened, slightly bent down, with three pairs of large spines projecting beyond the margin and numerous minute spinules or prickles. ‘Two pairs of well-defined pleure curving backwards; each pleura marked by median furrow dividing it into two unequal portions, of which the posterior is the narrower and more elevated. Hach pleura is produced beyond pygidial margin into short free point, forming thus the two anterior pairs of marginal spines, which also bear small lateral prickles (only occasionally preserved). Pleurze separated by well-marked interpleural furrows curving backwards, of which the first makes an angle of about 30° with the front margin, and the second makes an angle of about 60°-70° with the same. Between the second pleurz and the post-axial piece is a triangular, irregularly tuberculated area on each side with no furrow upon it. The posterior pair of spines are approximate and directed straight backwards, and are generally about equal in length to the second pair, from which they are removed by about twice the distance that they are from each other. MEASUREMENTS. mm. Length of trilobite ... a0¢ aye see cis cole SO Length of head-shield si Sas a 6°5 Width of head-shield (from tips of genal spines). ee ls 30 Length of thorax ... ane bb ae ese 75 Length of pygidium... 7-0 Width of pygidium ... 9°0 F. R. Cowper Reed—Some Wenlock Species of Lichas. if Remarks.—The head-shield shows considerable resemblance to that of L. anglicus (Beyr.); but the latter may be distinguished by (1) the more quadrato-oval shape of the anterior lateral bicomposite lobes of the glabella, owing to the second lateral furrow meeting the first lateral furrow at a right angle, (2) the greater size of the post-central lobe of the glabella, (3) the small outward bend in the first lateral furrows in the middle of the central lobe, (4) the absence of the basal portion of the axal furrow, (5) the smaller lateral expansion of the anterior end of the central lobe of the glabella, (6) the different shape of the free cheek, and (7) the regular curve described by the posterior margin of the head-shield. A comparison of Fletcher’s figure (pl. xxvii bis, fig. la) of L. anglicus plainly shows the points of difference. The glabella in LZ. anglicus is also generally of rather less width, but is somewhat longer ; and the head-shield is not so bent down in front, nor so swollen centrally. In the pygidium we see in L. hirsutus much resemblance to ZL. Haueri (Barr.),! and the head-shield, with the exception of the transverse post-central furrow, is likewise somewhat similar. The peculiar laterally angulated outline of the posterior margin of the head-shield and position of the spine on the free cheek is likewise met with in Z. Haueri and in other Bohemian species. The head-shield referred by Fletcher to Z. anglicus (pl. xxvii, figs. 1, la, 1b), but mentioned as being of a slightly unusual form (p. 236), should be attributed to Z. hirsutus, with which it agrees in all essential features. Barrande (op. cit., p. 602) considered that Z. hirsutus, Fletcher, was identical with his L. palmata (Barrande, op. cit., p. 599, pl. xxix, figs. 1-13), but remarks that one of Fletcher’s specimens (shown in fig. 5, pl. xxvii, Q.J.G.S., 1850, vol. vi) represents a different form to which the specific name L. hirsutus must be restricted. Probably Barrande meant fig. 7 instead of fig. 5, for the latter is attributed by Fletcher to LZ. Bucklandi in his explanation of plate xxvii. L. hirsutus, Fletcher (excluding fig. 7, pl. xxvii), however, differs from L. palmata in numerous points, the most important of which are the absence of the well-defined middle glabellar and occipital lobes, and in the pygidium the presence of only one strong axial ring followed by several incomplete rows of tubercles. These features are amply sufficient to separate it specifically. Licuas (CoRYDOCEPHALUS) HIRSUTUS, var. TUBERCULATUS (var. nOV.). (Pl. I, Fig. 6.) Several specimens of a Lichas from the Wenlock Limestone or Shale of Dudley show points of difference from the type-form of L. hirsutus almost sufficient to constitute a distinct species. In the head-shield the basal portion of the axal furrows is wanting, and the fixed cheeks are completely confluent with the middle lateral portions of the glabella; there is one conspicuously large tubercle on the middle of the fixed cheek, and the eye-lobe projects laterally in a very prominent manner; the occipital ring also bears a large 1 Barrande: Syst. Sil. Bohem., vol. i, p. 604, pl. xxviii, figs. 38-44. 8 F.. R. Cowper Reed—Some Wenlock Species of Lichas. median tubercle. There are only ten segments recognizable in the thorax in the one complete specimen which I have examined, but this probably only indicates immaturity. The pygidium has a large prominent central tubercle near its posterior end; the transverse rows of tubercles on the axis behind the first ring are very indistinct; the post-axial piece is very short and ill-defined. The two pairs of pleure have their free ends more elongated than is usual, the second pair indeed projecting back behind the posterior end of the pygidium and behind the third pair of spines, which are very short and blunt. Fletcher labelled one of these specimens LZ. Bucklandi (= L. anglicus), but Salter labelled another (2963) Z. hirsutus. From the presence of several specially large tubercles this variety may be termed tuberculatus. Licuas (CoRYDOCEPHALUS), sp. L. hirsutus (Fletcher), ‘‘young’’: Q.J.G.S., 1850, vol. vi, pl. xxvii, figs. 7, 7a. The pygidium figured by Fletcher as belonging to a young individual of Z. hirsutus, “from the great similarity in the arrange- ment of the tubercles on the axis and sides,’ shows such important differences that it does not seem possible to regard them as merely marking a stage of growth in an individual of this species. The pygidium is semicircular, with three pairs of marginal spines of sub- equal size. The axis is very broad, blunt, and subconical, reaching fully three-fourths the entire length of the pygidium, and occupying considerably more than its middle third. There is one strong ring at the front end of the axis, followed by two or three much narrower and fainter rings marked by tubercles. There is no distinct post-axial piece. The axal furrows are strong and deep. There are two pairs of pleuree on each side (not three ‘ribs’ as Fletcher states), curved backwards, and ending in short stout, backwardly directed free points on the margin. The surface of each pleura is divided down the centre by a strong median furrow, equal in strength to the inter- pleural furrows; the anterior and posterior parts of each pleura are of equal size and elevation, and each is ornamented by a single row of large tubercles. The posterior pair of spines is rather shorter than the first and second pairs, and its members are twice as closely approximated to each other as they are to the second pair of spines. A few large tubercles are somewhat regularly disposed on the axis and the portions of the lateral lobes behind the second pleure. The margin is strongly and sharply incurved below, and is marked by concentric raised striz, which also cross the under-surface of the spines. MEASUREMENTS. mm. Length of pygidium Width of pygidium Width of axis ... 586 sa Me ae Remarxks.—It is possible that the specimen above described belongs to an immature individual of some species, though probably not to I. hirsutus. It is advisable, therefore, in the absence of further evidence to leave it unassociated with any of the described species, and to refrain from considering it a new species. Co aT F. R. Cowper Reed—Some Wenlock Species of Lichas. 3g Licuas (Dicranopetris) Woopwarpt, sp. nov.’ (Pl. I, Figs. 7, 8.) L. Barrandii, Fletcher (pars): Q.J.G.8., 1850, vol. vi, p. 238, pl. xxvu, fig. 10 (non pl. xxvii bis, fig. 5). The description which Fletcher gave of the species which he called LZ. Barrandii corresponds exactly with his fig. 5, pl. xxvii bis, and with the two specimens on which this was founded, but it does not at all agree with the figure on the preceding plate (fig. 10, pl. xxvii), nor with the specimen which it represents, and the only point in the description which is borrowed from it refers to the con- centric striation of the under side, which is not seen on the other specimens. A suspicion that two species have been confounded at once arises, and an examination of the type-specimens which are in the Woodwardian Museum confirms it. . Moreover, the type-specimen represented in fig. 10, pl. xxvii shows only the inner surface of the shell, but another showing the actual outer surface in relief has come into our possession with the remainder of Fletcher’s collection presented in 1897, and it was labelled by Fletcher himself L. Barrandii. From this material a fairly complete description of this new species can be given, so far as the pygidial characters are concerned. Pygidium broadly parabolic; ratio of length to width as 3: 4. Axis rounded, convex, slightly elevated above side-lobes; nearly one-third the width of the pygidium at front end; short, broad, not as long as broad; sides converge posteriorly at angle of about 00°; abruptly truncated at posterior end by straight transverse furrow; bears two well-marked continuous rings at anterior end. Axal furrows well-marked, nearly straight. Transverse furrow defining termination of axis weak in centre, strongly impressed at sides. Lateral lobes flattened, nearly horizontally extended, furnished with six pairs of furrows of equal strength; each lobe consisting of three broad foliaceous pleure with free falcate, backwardly directed ends. First two pleure on each side complete, and well-defined by ‘strong interpleural furrows of equal depth, the first furrow making an angle of about 30° with the front edge of the pygidium, and the second an angle of about 60°. First pleura marked by diagonal furrow which runs parallel to the first interpleural furrow, but dies out before reaching the free point of the pleura. Second pleura marked by similar furrow starting from axal furrow at the point of origin of first interpleural furrow, and running thence parallel to second interpleural furrow, but dying out before reaching free point. Axal furrows continued backwards behind axis, at first with same angle of convergence and then almost parallel to each other, but disappearing at some distance from the posterior margin of pygidium. The post-axial median piece enclosed between them is narrow, and slopes down rapidly to level of side-lobes. Third pair of pleure 1 This species is mentioned by the author in his paper on the genus Lichas: Q.J.G.S., 1902, vol. lviii, pp. 72 and 82. 10 F. R. Cowper Reed—Some Wenlock Species of Lichas. between second pair of pleure and post-axial median piece; each third pleura ends in backwardly directed free point, and is crossed by diagonal furrow making an angle of about 80°-90° with front edge of pygidium. Free points of third pair of pleurze approximate- (not well preserved) ; margin of pygidium incurved, and shows on under-surface concentric equidistant raised thread-like lines. Ornamentation consists of large round tubercles of two or three graduated sizes, not very closely set. Owing to the breaking off of the heads of the larger tubercles (which are hollow), circular pits with a raised margin are left as cicatrices. MEASUREMENTS. IL (Fletcher’s figured specimen). II. Length of pygidium a an Boe B se c. 31 mm. Width of pygidium oe ae Ba 46 mm. sls LO. Width of axis at front end te son 1B 35 ie UBB 96 Length of axis... hen $50 sae Te ad na OO 56 Remarks.—This species differs from L. Barrandii (Q.J.G.S., 1850,. vol. vi, pl. xxvii bis, fig. 5) by the following features: (1) greater relative length of pygidium, (2) narrower and shorter axis, (3) only two ‘axial rings, (4) no axial tubercle, (5) straight transverse posterior furrow defining end of axis, (6) longer post-axial median. piece, (7) less backwardly curved pleura, (8) course of furrows on lateral lobes, (9) coarser tuberculation. The pygidium of L. scaber (Beyr.) bears a considerable resemblance to that of L. Woodwardi. It may also be mentioned that the ornamentation of L. Grayi, of which only the head-shield is known from the Wenlock Limestone, is somewhat similar. Licnas (Dicranopextis) Barranpet, Fletcher (emend.). Lichas Barrandii, Fletcher (pars): Q.J.G.S., 1850, vol. vi, p. 238, pl. xxvii dis, fig. 5 (non pl. xxvu, fig. 10). Fletcher’s diagnosis of this species, with the exception of the statement that “the incurved under-portion is concentrically striated,” which cannot be verified with our present material, applies to fig. 5, pl. xxvii bis, and does not need any amplification. It may, however, be remarked that the figure is partly a restoration based on two nearly complete specimens (b 28, 6 29 in Salter’s Catalogue), the measurements of which are as follows :— I (029). II (6 28). Length of pygidium ... wns 20 mm. mh 18 mm. Width (at front end) of pyg eidium ae ® as 24s. Width of axis Cy front end) ... See 1B 5. oan iLL Length of axis.. ane ae wes 10 sae ? be) It is unfortunate that of this species only the pygidium is known at present. In one of the specimens (I) a faint transverse furrow, incomplete in the middle, defines the posterior end of the axis, recalling the much stronger furrow seen in L. Woodwardi. Fletcher does not mention it, and it appears to be obsolete in the better F. R. Cowper Reed—Some Wenlock Species of Lichas. 11 preserved specimen (II), which he used chiefly in drawing fig. 5,. pl. xxvii bis. Licuas (Dicranorettis ?) Saurert, Fletcher. L. Salteri, Fletcher: Q.J.G.S., 1850, vol. vi, p. 237, pl. xxvii, figs. 9594; pl. xxvii dis, fig. 4. Lindstrém? records this species from Gotland, and believes that L. laticeps, Angelin (Pal. Scan., 1854, pp. 70, 72, t. xxxvii, figs. 8, 8a, non t. xxxviili, fig. 5), and L. gibbus, Angelin (Pal. Scan., p. 71, t. xxxvii, fig. 1, pygidium only), are synonyms. The rows of large: tubercles on the glabella and side-lobes are held by Lindstrém to. be the particular characteristic of the species; and unfortunately no part but the head-shield, and that incomplete, is known from the Wenlock Limestone. It is impossible to feel on safe ground in assigning any of the isolated pygidia of this horizon to L. Salteri, but Lindstrém * considers the pygidium figured by Angelin (op. cit. sup.) as L. gibbus as probably belonging to this species, and describes it as possessing a linear axis narrowing posteriorly, furnished with about eleven segments, of which the posterior ones are inconspicuous ; anarrow prolongation extends behind it towards the margin. Three small pleura-like ribs are given off on each side from rather in front of the middle of the axis. There is a raised border round the pygidium, and from it short, backwardly directed spines project near the terminations of the ribs. Between the two posterior ones are three pairs of small spines, one of which projects from the axis. It is to be regretted that Lindstrém did not give a figure of this specimen, as Angelin’s figure leaves much to be desired, and it is difficult to form an adequate idea of the pygidial characters from the description. The old generic designation Trochurus is revived by Lindstrém for this species, and applied also to J. pusillus, Angelin, and T. Bucklandi, Milne Edwards (= L. anglicus, Beyrich). Beyrich, however, in 1846 (Untersuch. tiber Trilob.) declared that this name,. which he had instituted in 1845 (Ueber Boh. Trilob., p. 31, fig. 14), should be allowed to drop, as the genus had been founded on a specimen consisting of portions of two distinct trilobites (i.e. a head of Staurocephalus Murchisoni combined with a pygidium of L. speciosus, Beyr. [= L. palmata, Barrande]). Barrande (Syst. Sil. Boh., vol. i, p- 603) points out this fact, and also rejects for this reason the specific name ZL. speciosus, which Beyrich had given in 1845 to the composite form. It accordingly appears inadvisable to revive the name Trochurus under any form. Beyrich himself employed in 1846 Goldfuss’ earlier name Arges (1839) for his species L. speciosus (= L. palmata, Barr.), but, as previously pointed out by the present writer,® this name is preoccupied. 1 Lindstrém: Gotl. Silur. Crust. Ofv. K. Vet. Akad. Forhandl., 1885, No. 6, p- 60 (Lrochurus Salteri) ; List of the Fossils of the Upper Silurian Formation of Gotland, Stockholm, 1885, p. 3 (Zrochurus Salteri). 2 Gotl. Silur. Crust. Ofv. K. Vet. Akad. Forhandl., 1885, p. 60. 3 Q.J.G.S., 1902, vol. lviii, p. 60. 12 Rev. J. F. Blake—Form of Sedimentary Deposits. EXPLANATION. OF PLATE I. Fic. 1.—Lichas (Corydocephalus) anglicus, var. wenlockensis. Outline restoration of pygidium. x 3. 99 ot be ee: ) anglicus, var. obtusicaudatus. Outline restoration of pygidium. 9 OL. "(Cor ydo.) hirsutus. Specimen with eleven thoracic segments. x 23 (partly restored). Woodw. Mus. », 4.—Ditto. Specimen with eleven thoracic segments. x 22 (partly restored). Brit. Mus. _ 5, 0.—Ditto. Outline restoration of pygidium from Fletcher’s type. x 3. », 6.—Ditto. Var. tuberculatus. x 3. Woodw. Mus. >, @.—L. (Dicranopeltis) Woodwardi. x 14. Woodw. Mus. » 8.—Ditto. Nat.size. Figured by Fletcher as Z. Barrandii (Q.J.G.S., vol. v1, pl. xxvii, fig. 10). Woodw. Mus. IIJ.—On tHe Oriainat Form or Sepimentary Deposits.! By the Rev. J. F. Buaxr, M.A., F.G.S. HE form of the deposits that are taking place on the sea-bottom at the present day is one of the essential elements required to be known when we wish to interpret the submarine contours, as throwing light on the submergence or elevation of the land in late geological times, or when we propose to use the variation of thickness of the strata deposited during any epoch as an indication of the position of the shore-lines at that time. In the case of deposits in small or temporary masses of water, their form and arrangement may sometimes be observed directly ; but in the case of the deposits in the sea, where we can neither remove the water nor make borings beneath it, we can only avail ourselves of theoretical considerations. It might have been expected that the original form of various sedimentary deposits would have been considered in detail long ago, but as a matter of fact the few writers who have touched upon the question have mostly been content with the assumption that deposits taken as a whole are thickest near the source of supply, and the figures given in illustration of the arrangement of various kinds, and thereby the shape of each, are remarkable for their variety.” As the theoretical results at which I have arrived differ funda- mentally from the ordinary assumptions, it is to be hoped that some one will be able to point out the fallacy, if any, which has led me astray, and to explain more satisfactorily the observed features which appear to confirm the theory. It will be seen, however, that it is just those writers who have paid most attention to the matter who approach most nearly to agreement with my results. The actual form of any deposit on the sea-bottom, supposed, for the sake of argument, to be flat, will depend first upon the forces to which the material is subject, and secondly upon the nature of the 1 A paper read at the Meeting of the British Association, Belfast, September, 1902. 2 See Godwin-Austen, Q.J.G.S., vol. vi, p. 82, fig. 2 2 (1850); Hull, Ou G.S., vol. xviii, p. 135, fig. 4 (1862) ; Green, Lectures on Coal, p- 9 (1878), and Geology, p. 211 (1882) ; Page & Lapworth, Introductory Textbook, p. 59, fig. 22 (1888); Marr, Principles of Stratigrapl hical Geology, p. 117, fig. 13 (1898) ; Watts, Geology for Beginners, p. 78, fig. 47 (1898). Geol Mag.1903. Decade IV. Vol.X PL.1. “y oy Pst he PE Ab
a 8. Sandstone, brown, micaceous ; Modiola minima, Schizodus ... 0 3
Soy] 9. Shales, brown, clayey a, ; 5 AUG,
14 | 10. Sandstone, yellowish (weathering brown), micaceous ; “Uoiiola
minima, Schizodus, annelid-tracks, fish scales ... ... 0 5
If this record be read with those made at Crowle and Woodnastent
a generalised section will be had of the Rhatic series as it occurs
in Worcestershire.
VIII.—Soratcues on Minerars in Turn Sections.
By H. Sranuzy Juvons, M.A., F.G.S., Lecturer in Mineralogy and Demonstrator
in Geology in the University of Sydney.
d Lien is an exceedingly simple method of distinguishing biotite
from brown hornblende in thin sections under the microscope,
which, so far as I am aware, has not yet been described. As it
may possibly be of assistance to beginners, I submit a brief
account thereof.
Let any section of biotite which shows the cleavage and pleo-
chroism be turned between crossed nicols until the light is almost, but
' On authority of Mr. W. J. Harrison, F.G.S.: vide Proc. Dudley and Midland
Geol. Soc., vol. 1ii, No. 5 (1877), p. 121.
Professor H. S. Jevons—Scratches on Minerals. 83
not quite extinguished. When closely examined with a low power
it will be seen to be irregularly speckled with small spots and
patches of light, generally oval or elongated in shape, which often
give its surface a rough or shagreened appearance. These spots
are still visible if the section be turned to complete extinction, and
are then cut in two longitudinally by a dark line. If the section
be further turned to the other side of the position of extinction they
resume their original shape, but are seen to have changed their
position slightly.
The cause of this want of uniformity in extinction is easily
ascertained by examination with a high power. Wherever these
light spots occur the cleavage lines are seen to be bent laterally
from their normal course into a V-shape, doubtless by the scratching
action of the coarser grains of the polishing material during the
final stage in the grinding of the section. The V’s piled upon one
another simulate a cross section of a pointed anticline or syncline of
great vertical range.
It is evident, therefore, that when the section as a whole is at its
position of extinction, the mica along both arms of the V lies in
such directions that light will get through it. The dark line before
mentioned as cutting the spots longitudinally when the section is
in this position passes through the apices of the V’s, and is due to
the fact that between their two arms the mica must lie for a short
distance in its original direction, now the direction of extinction.
The spots are brightest, however, when the section as a whole is
not quite extinguished, for then one arm of the V is completely
extinguished, whilst the other is well on towards its position of
maximum illumination. On turning the biotite from one side to
a similar position on the other side of its direction of extinction
the effect is similar, but reversed ; what was previously the darker
arm of the V has become the lighter, and vice versd. The same
effect is visible in less marked degree with only one nicol in use, on
account of the strong pleochroism of biotite. The angular displace-
ment of the arms of the V is sufficient distinctly to alter the amount
of absorption.
The appearance described is presented, in my experience, only by
such minerals as are soft, and have a very good cleavage. It is
visible in biotite, muscovite, and tale, and a few other soft minerals
rare in rock sections. Practically, every section of these minerals
which I have examined shows the effect, excepting those parallel to
the cleavage, and I have never seen it in hornblende or any member
of the pyroxene or amphibole family.
If the attention of the beginner has once been called to these
‘scratches, he never mistakes hornblende for biotite; and only under
the rarest circumstances connected with the preparation of the
section could he mistake biotite for hornblende, even if relying
solely on this test. To the more advanced student the appearance
may occasionally prove of service in the identification of minerals, as
evidence of their softness.
84 Samuel Moore—An Unmapped Toadstone.
1TX.—Norr on an Unmarrep Toapstont Brp IN THE Dea eae
Mountain Limestone.!
By Samvuet Moorgz, Esq.
N the Summer of 1901 I found in a pasture, between Oxlow
Rake and Cop Round (IX §.E.), some blocks of Toadstone in
a bed of clay that has all the characteristics of decomposed Toad-
stone. The clay was being dug for puddling a new mere, and the
deposit is well known to natives. I traced the outcrop south-west to
Starvehouse Mine, and my inference that the clay was decomposed
Toadstone was soon verified by the Toadstone itself coming to day-
light and replacing the clay. I did nothing more that year, but in
the Summer of last year I continued to follow the bed, and have
traced it as far as Bushy Heath House (XV N.E.), a distance of
about two miles from its starting-point.
The outcrop starts as a clay bed, at the southern end of an
enclosure called Old Moor (IX §.H.), at a point about 50 yards
south-east of two old mine shafts, and where a spring issues from
under the limestone scarp, at a height of 1,400 feet above mean
sea-level (by aneroid). Thence it runs in a general south-west
direction for half a mile, along a line of five springs at the base
of the limestone escarpment, to the north wall of Starvehouse Mine
(IX §.H.), which it cuts at an altitude of 1,500 feet.
There is no throw at the Starvehouse lode, and the bed contours
round the point of Cop Round and crosses Dick Lane 380 yards
from the summit gate (1,510 feet); from there it runs south-east
with the dip of the limestone to Moss Rake (IX S8.E.), the base
passing just above the letter n of Piece Barn on the map. It
reaches the lode at 1,350 feet. Here the bed is faulted and thrown
up to the north, and the top starts afresh about 180 yards up the
lode, at an altitude of 1,420 feet.
The top then runs, along the base of a limestone scarp, to a point
beneath the Old Roman Camp on Batham Gate (IX S8.E.), crosses
the road at the gate to The Holmes (XV N.H.), and runs down,
through the farmyard, to the continuation of the Shuttle Rake lode,
below the old Calve Stones Mine plantation.
There appears to be no fault at this lode, but the bottom of the
valley is flat and filled with superficial deposits which conceal the
outcrop.
From The Holmes the bed is traceable still in a general south-
east direction, as far as an old quarry (XV N.E.) at an altitude of
1,300 feet, and 300 yards N.N.W. from Bushy Heath Farmhouse.
From there to Chap Maiden Mine (1,276 /) the traces are indistinct,
owing to flat ground. Beyond this point I have not at present
traced it, but next Summer I hope to do so.
The bed of Toadstone here described lies above the topmost bed
shown on the 1 inch map of the Geological Survey, and is separated
from it by nearly 150 feet of solid limestone. It varies in thickness :
1 See Geol. Surv. Map 81 N.E., original 1 inch scale; Maps IX S.E. and
XV N.E., 6 inch Ordnance Survey.
Reviews— The Paleontographical Society. 85
at the start on the Old Moor I should put it at 15 or 20 feet of
elay, but it thickens in a south-west direction, and at Cop Round
I estimate it to be 60 to 80 feet thick, which thickness it maintains
up to the Moss Rake. After that it seems to thin out; but just
above The Holmes and beneath the Roman Camp it crops out
strongly again and is about 80 feet thick, if not more. From The
Holmes to Bushy Heath I could not ascertain the thickness. At
Cop Round some blocks are concretionary, and I have not noticed
any columnar structure. The bed seems to decompose into clay
very freely where it is not thick.
I wish to draw attention to this bed of Toadstone because I think
it will be of importance in the stratigraphy of the Toadstone beds
near Tideswell, Litton, and Wheston ; and further, in order that the
bed may not be overlooked in any future resurvey of the country :
it is not a prominent bed like the one immediately below it.
With regard to this latter bed I may as well point out what
strikes me as an error on the part of the Geological Survey. On their
1’ map 81 N.E. the bed is made to start at a point between Eldon
Hole (IX S§.H.) and the summit of Hldon Hill, at 1,480 feet
altitude, where the limestone beds dip true E. 40°S., at an angle
of 6°; it is then drawn to run down into Cunningsdale, round
Oxlow, across Oxlow Rake to Oxlow Dam, and on to The Cop
Farmhouse. In the length between Eldon Hill and Oxlow Dam
I cannot find any evidence of an outcrop of Toadstone, or even of
clay that might be decomposed Toadstone. As one traces the bed west-
ward from The Cop Farmhouse (IX §.E.) it appears to thin out, and.
vanish at a spring just outside the south-west corner of Starvehouse
Mine. Moreover, the line as drawn in its descent from Watts
Plantation (IX 8.E.) to the bottom of Cunningsdale, and in its ascent
again to Oxlow Rake, does not follow the dip, but cuts across the
limestone beds in a manner not usual with the Toadstone in this
part of the country.
J5%) del} W/) aE DS WW Ss
I.—Tue PALMonTOGRAPHICAL Socrety oF Lonpon.
Tue ANNUAL VOLUME oF THE PALMONTOGRAPHICAL SocIETY FOR
1902: Vol. LVI. 4to. (London: printed for the Society.
Dulau & Co., Agents for the Society, 87, Soho Square, W.
Price to Subscribers 21s. per annum.)
GAIN it is our pleasant task to welcome the issue of another
volume (larger than usual) of this Society’s admirable
publications, which has for its object the description and figuring
of all the known British fossils.
When its heroic founders set out on this enterprising task, nearly
sixty years ago, they were doubtless as courageous as Jason and
his Argonauts when they set sail in the good ship Argo to fetch
the golden fleece; but, like Jason and his Grecian heroes, they
must soon have found that they had undertaken a very arduous
86 Reviews—The Paleontographical Society.
task; many of the brave workers have died since then, yet the task
still remains unfinished. Yet notwithstanding our losses, the
heroes of our modern Argo are an indomitable body, and its ranks
are ever being renewed by fresh paleontological volunteers.
In our last number we recorded the death of our late Secretary,
Professor Wiltshire, who for 36 years had carried on the adminis-
tration of the Society. His place is now filled by Dr. Arthur
Smith Woodward, F.R.S., while many new contributors (himself
among the number) have been added to our body.
In the present volume Professor §. H. Reynolds takes up the
unfinished work on “The Pleistocene Mammalia,” commenced by
Messrs. Boyd Dawkins & Sanford in 1864, and continued till
1871; since then, with the exception of a short account of the
Pleistocene Cervide by Professor Boyd Dawkins in 1886, the
original authors have abandoned their work, which is now taken
up by Mr. Reynolds. The present fasciculus forms part 1 of
vol. ii, and is devoted to “The Cave Hyena,” the illustrations
being mostly taken from the wonderful series of Hyena remains
from Wookey Hole in the Mendips, now preserved in the Taunton
Museum. Six out of the fourteen plates were executed long ago by
the late Mr. W. Bidgood, formerly curator of the Taunton Museum ;
the others are newly drawn by Mr. J. Green, one or two from the
British Museum collection and others from that of Owens College,
Manchester. The Society is to be congratulated upon securing
the services of Professor Reynolds for this important work on
vertebrate paleontology.
The next monograph is a new one on the “ Fossil Fishes of the
English Chalk,” by Dr. Arthur Smith Woodward, and is illustrated
by thirteen very fine plates by Mr. A. H. Searle and twelve drawings
and restorations of urypholis, Odontostomus, Chlorophthalmus
(recent), Sardinioides, Hoplopteryx (Beryx), Beryx splendens.
(recent), Berycopsis elegans, Aipichthys, admirably drawn by Miss
G. M. Woodward. One plate is an autotype of a group of Chalk
fishes of the genus Hoplopteryx from the Beckles Collection in
the British Museum, by Mr. Green. Fifty-six pages of descriptive
letterpress are issued with this very important memoir.
The third monograph is a continuation of the ‘Cretaceous
Lamellibranchia of England,” by Henry Woods, M.A., part iv,
being devoted to the Chalk Pectens. The twelve plates are very
ably rendered by Mr. Hollick.
The concluding monograph is a continuation of that on British
Graptolites by Gertrude L. Elles & Ethel M. R. Wood, edited by
Prof. Charles Lapworth, F.R.S. There is an interesting introduction,
and the following genera are described and figured: Tetragraptus,
Schizograptus, Trochograptus, Holograptus, Dichograptus, Logano-
graptus, Clonograptus, Temnograptus, Bryograptus, Azygograptus, and
Phyllograptus. We confess to a feeling of disappointment in the
production of the very careful original drawings by process in these
plates. We prefer an accurate, clear, distinct outline to each figure.
We are quite sure these are most accurate, but they are neither so
Reviews—Sherborn’s Index Animalium. 87
clear nor so distinct as we could desire; and there is a dread that
this highly-surfaced paper will, after some years, perish, being
overloaded with kaolin. There are quite a number of process-blocks
in the text, some of which give most clear details, such as we desire,
but others are less satisfactory. We look back with admiration}to
Professor Lapworth’s own original drawings in this Macazinu, the
Quart. Journ. Geol. Soc., and elsewhere, which are to our minds
more satisfying, notwithstanding the great labour which the authors
have expended on the present monograph.
Taken as an annual issue, this is a fine volume, containing, as
it does, 207 pages of descriptive text, 47 plates, and numerous
illustrations in the text, together with 30 pages of introductory
matter, the whole of which can be obtained for the small subscription
of one guinea.
We expect to find that, after this announcement, Messrs.
Dulau & Co., 87, Soho Square, and the Secretary, Dr. Arthur Smith
Woodward, will have a busy time in satisfying the demands of the
many new and enthusiastic subscribers who will send in their names
and cheques !
I].—Suergorn’s Inpex Nominum Animauium, 1758-1800.
InpEX ANIMALIUM, sive index nominum que ab A.D. MDCOCLVIII
generibus et speciebus animalium imposita sunt societatibus
eruditorum adjuvantibus, a Caronto Davies SHERBORN, confectus,
sectio prima a kalendis januariis mpccLvi11 usque ad finem
Decembris mpccc. Cantabrigise e typographio academico
mpcoccu. Roy. 8vo; pp. lix, 1196. (London: C. J. Clay & Sons,
Cambridge University Press Warehouse, Ave Maria Lane, 1902.
Price 25s. net.)
HE Syndics of the Cambridge University Press having undertaken
the publication of the first part of the “ Index Animalium,” to
the preparation of which Mr. C. Davies Sherborn has devoted so
many years, it seems desirable to explain the nature of the work
upon which so much time, labour, and expense have been bestowed.
The object of the Index is to provide zoologists with a complete list
of all generic and specific names given by authors to animals, both
recent and fossil, since January Ist, 1758, the date of the tenth
edition of Linnzeus’ “Systema Nature.” With each name is given
an exact date, and a reference intelligible to the layman as well as
to the specialist.
The British Association appointed a Special Committee to watch
over the inception and progress of the work, the preparation of which
was undertaken in 1890.' Financial support has been given by the
British Association, the Royal and the Zoological Societies, while
the authorities of the British Museum (Natural History) have afforded
continual assistance.
1 An interval of three years was unfortunately lost by the author from ill-health,
so that the completion of this first volume has occupied a period of eight years, a no
inconsiderable task for one man to undertake and carry through to completion.
88 Reviews—Sherborn’s Index Animalium.
Similar works have been produced before, but no one book has
yet appeared attempting to supply references to all names given to
both fossil and recent animals, nor has any definite attempt been
made heretofore to fix an accurate date to each name.
This work will, of course, supersede Agassiz and Scudder, and
must be absolutely indispensable to zoologists of all countries. It
will be to the student of animal life what the “Index Kewensis” is
to the botanist, and, indeed, far more, as the last-named work refers
only to Phanerogams, whereas the “ Index Animalium ” includes all
groups of animals, and both recent and fossil forms. The portion of
the work already completed and now issued from the press of the
University of Cambridge covers the period from 1758 to 1800,
consists of 61,600 entries, and fills 1,196 pages royal octavo.
In 1897 Dr. Sclater suggested to the Committee that, in view of
the long time that must elapse before the completion of the whole
manuscript, which it was proposed should embrace the period from
1758 to 1900, it would be well if a portion were prepared and
published as a specimen of the whole. This suggestion has been
acted upon, and there is now offered to the consideration of zoologists
that part covering the years 1758 to 1800 inclusive. During the
progress of this earlier portion of the manuscript it became apparent
that a great deal of the literature required was not to be found in
England, and it is satisfactory to be able to say that, with a few
unimportant exceptions, the bulk of the 1,300 volumes required
have either been seen, or else seen and acquired for some one or
other of the libraries accessible to the public. ‘‘The search for
these volumes,” says Mr. Sherborn, “ has been not the least interesting
part of my labours. Such as have eluded my search are mentioned
in ‘ Libri desiderati,’ where a complete enumeration of the books
consulted has been given in a second list, this seeming to be
advisable and useful; and at the same time such notes are given
on them as would be of use to those who might wish to consider or
purchase them.”
“‘T would like to say that, with the exception of some fifty entries
kindly made for me by my friend Dr. Bather in Stockholm, and by
Professor Perez in Bordeaux, every entry has been recorded from
the original, arranged, sorted, checked, and passed for press by
myself. I therefore beg the indulgence of those who use this book
for any error of commission or omission that may be found. And
I may add that a note of any such error will be especially valuable
for inclusion in the second part of my ‘ Index Animalium.’”
We heartily commend this important work to the attention of
all librarians, curators, and zoologists in all the world, for none can
work without it. It is like the “ Postal Guide,” ‘“ Bradshaw,” or
“‘Whitaker’s Almanac,” a handy book of reference, containing the
scientific names of beasts of all kinds, and must be on the bookshelf
of every library embracing Natural History.
We earnestly hope the author’s valuable life may be spared to see
the completion of the next century of his Index through the
press, the manuscript for which is already far advanced.
Reports and Proceedings—Geological Society of London. 89
The later years will be not only of far greater importance to
zoologists, but will be a thousandfold more prolific in the number
of works to be referred to, and of the objects described in them,
than those of the previous half-century. We compliment the author
on the grand volume he has produced, and the Syndics of the
Cambridge University Press for having printed it in so accurate and
admirable a manner.
JegI IS OQ IS) eRANPID) | JP weyOVS- Dap Dac Crs).
GEOLOGICAL Society or Lonpon.
I.—December 3rd, 1902.— Professor Charles Lapworth, LL.D.,
F.R.S., President, in the Chair. The following communications
were read :—
1. “On some Well-sections in Suffolk.” By William Whitaker,
Hsq., B.A., ¥.R.S., F.G.S.
Notes of thirty-one new wells have accumulated since 1895, some
of them giving results which could not have been expected. A trial
boring for the Woodbridge Waterworks Company gave a depth
of 1833 feet down to Hocene beds, and a thickness of Crag about
double of any before observed in the neighbourhood. An analysis
of the saline, hard water yielded is given. Three explanations are
suggested: a channel, a huge ‘pipe’ in the Chalk, or a disturbance
such as a fault or a landslip; but the author is not satisfied with
any of them. ‘Two borings at Lowestoft show that Crag extends
to a depth of 240 feet in one case and over 200 feet in another,
confirming estimates of Mr. Harmer and Mr. Clement Reid. In one
of these, Chalk was reached at 475 feet. Three other wells in the
neighbourhood confirm the great depth of the newer Tertiary strata.
Sections are also given from the following places :—Boulge, Hitcham
Street, Ipswich (corroborating the evidence for a deep channel filled
with Drift given by the section at St. Peter’s Quay, New Mill),
Shotley, Stansfield, and Brettenham Park. The last shows the
greatest thickness of Drift recorded in the county, namely, 312 feet.
2. “The Cellular Magnesian Limestone of Durham.” By George
Abbott, Esq., M.R.C.S., F.G.S.
The Permian Limestone covers about 14 square miles near
Sunderland ; it alternates with beds of marl containing concretionary
limestone-balls, and attains a thickness of 65 feet or so. The
cellular limestones frequently contain more than 97 per cent. of
calcium-carbonate. Magnesium-carbonate occupies the interspaces
or ‘cells’ of this limestone, and also the spaces between the balls.
The hundred or more patterns met with in it can be arranged into
two chief classes, conveniently termed honeycomb and coralloid,
each with two varieties; and each class has four distinct stages,
both classes having begun with either parallel or divergent systems
of rods. ‘The second stage is the development of nodes at regular
-distances on neighbouring rods; and these in the third stage, by
90 Reports and Proceedings—Geological Society of London.
lateral growth, become bands. Finally, in the fourth stage the
interspaces become filled up. The upper beds are usually the most.
nearly solid. In the coralloid class the nodes and bands are smaller
and more numerous than in the honeycomb class. In both classes.
tubes are frequently formed. The rods have generally grown.
downwards, but upward and lateral growth is common. A section
of Fulwell Quarry is given.
I1.—December 17th, 1902.—Professor Charles Lapworth, LL.D.,
F.R.S., President, in the Chair. The following communications-
were read :—
1. “Note on the Magnetite Mines near Cogne (Graian Alps).”
By Professor T. G. Bonney, D.Sc., LL.D., F.RB.S., F.G.S.
These mines have been worked probably since Roman times, but
are now almost deserted. They are situated in the Val de Cogne,
one of the larger tributaries of the Val d’Aosta from the Graian
Alps. The author, in company with the Rev. E. Hill, last Summer
examined two localities where the ore has been worked. At one,
the Filon Licone, the mass of magnetite is probably about 80 or 90
feet thick and some five times as long. At the other place, the
Filon Larsine, the mass apparently is not nearly so thick. The ore
is a pure magnetite, jointed like a serpentine, a thin steatitic film.
being often present on the faces. At both localities the magnetite
is found to pass rapidly into an ordinary serpentine, the transitional.
rock being a serpentinized variety of the cumberlandite described
by Professor Wadsworth in his “ Lithological Studies.” The ser-
pentine is intercalated, like a sill, between two thick masses of
cale-mica-schists, with which green schists (actinolitic) are as usual.
associated, no doubt intrusively. All these represent types common
in the Alps. The author discusses the relations of the magnetite
and serpentine, which, in his opinion, cannot be explained either
by mineral change or by differentiation in sitz, but indicate that
a magnetitic must have been separated from a peridotic magma at
some considerable depth below the surface, and the former, when.
nearly or quite solid, must have been brought up, fragment-like,
by the latter; as in the case of metallic iron and basalt at Ovifak
(Greenland).
2. “The Elk (Alces machlis, Gray) in the Thames Valley.” By
Edwin Tulley Newton, Esq., F.R.S., F.G.S.
During the construction of the Staines Reservoirs some mammalian
remains were obtained from the alluvium of the Wraysbury River,.
near the Thames at Youveney. At the request of Mr. T. I. Pocock,
of the Geological Survey, who is working in the district, the
engineers, Messrs. Walter Hunter and R. HE. Middleton, courteously
submitted their specimens to the author, who recognized among
them the skull and antlers, with other parts of the skeleton, of
a true elk (Alces machlis). These are described; allusion is made-
to the earlier records of this animal in Britain; and its distribution.
in time in this country, on the continent of Europe, and in North
Reports and Proceedings—G'eological Society of London. 91
America is also discussed. It appears that Alees machlis has been
frequently found in peaty deposits in many parts of Great Britain
and on the continent of Hurope, but never in Britain in association
with the mammoth; and it seems probable that in Hurope and
North America it was a rare animal in Pleistocene times,.if indeed
it was present before the close of that period.
€
3. “ Observations on the Tiree Marble, with Notes on others from
Iona.” By Ananda K. Coomaraswamy, Hsq., B.Sc., F.L.S., F.G.S.
The gneiss near Balephetrish has a general south-westerly and
north-easterly trend, and the limestone occurs in it as lenticles of
various sizes, having a similar foliation. Descriptions of pink, grey,
and white varieties of the limestone in this locality are given. The
inclusions comprise those of gneiss containing quartz, felspars, horn-
blende, augite, scapolite, and sphene as characteristic minerals, and
mineral aggregates consisting of sahlite, coccolite, scapolite, sphene,
apatite, calcite, and mica. The contact-phenomena are not specially
well displayed, but several instances are described ; and in these the
minerals of the modified gneiss interlock with those of the modified
limestone, and there is no actual line of junction seen under the
microscope, although an abrupt change is evident. The dynamic
phenomena include the rounding of the minerals (frequently, how-
ever, an original character) and the formation of ‘augen.’ The
carbonates are present as a fine-grained granular matrix, the result
of the breaking down of larger grains, probably at a temperature
not above 300° C., as indicated by the experiments of Adams and
Nicolson. Although there are exceptions, gneiss-inclusions and
mineral aggregates have usually been protected from the effects of
extreme pressure. The description of minerals includes carbonates,
pyroxene, amphibole, forsterite, scapolite, sphene, mica, apatite, and
spinel. White, greenish, and black marbles are described from Iona,
where they are associated with actinolite-felspar-schists and others ;
they are included in the gneiss. Sedimentary rocks suggestive of
Torridon Sandstone occur along the eastern shore of Iona.
III. — January 7th, 1903.—Professor Charles Lapworth, LL.D.,
F.R.S., President, in the Chair. The following communication
was read :—
““On the Discovery of an Ossiferous Cavern of Pliocene Age
at Dove Holes, Buxton (Derbyshire).” By William Boyd Dawkins,
M.A., D.Sc., F.R.S., F.G.S., Professor of Geology in Owens College,
Victoria University (Manchester).
The Carboniferous Limestone, riddled with fissures and potholes,
in the neighbourhood of Dove Holes, has from time to time, in the
course of the working of the quarries, yielded remains of extinct
mammalia of Pleistocene age. The latest discovery of a group of
mammalia, of far higher antiquity than the Pleistocene, is now
brought before this Society. The Victory Quarry, Bibbington, in
which the discovery was made, is excavated in a rolling plateau of
92 Reports and Proceedings—Geological Society of London.
Carboniferous Limestone, from 1100 to 1200 feet above Ordnance-
datum, and forming at this spot the water-parting between the
tributaries of the Goyte, flowing past Chapel-en-le-Frith westward
into the Mersey, and those flowing southward and eastward, past
Buxton, to join the Derwent. It is a little to the north of the
centre of the divide. On the western side the limestone dips at
an angle of 15° underneath the Yoredale sandstones and grit, which
form the lower half of a range of hills, extending southward to
Buxton and beyond. The upper half is composed of shales and
sandstones of the Millstone Grit Series, that rise in Black Edge
to a height of 1662 feet. The drainage of the eastern slope of
these hills passes downward, until it arrives at the limestone, where
it sinks into the rock, through the many swallow-holes which mark
the upper boundary of the limestone. There are no surface streams
in the limestone in the immediate neighbourhood of the Victory
Quarry, which, from its position on the divide, could not, under
existing geographical conditions, receive the drainage from this
western range of hills or any other source.
In the course of working the quarry, in the beginning of 1901,
a cave was discovered, and fully exposed in the course of 1902.
It was about 90 feet long, 15 feet high, and 4 feet broad. It ran
nearly horizontally north and south, and consisted of a large
chamber and a small passage, both eroded in a master-joint. On
the south it contracted to a dead end, now quarried away. Its
continuation to the north is obscured by a great accumulation of
broken rock and clay, which has not yet been removed. It was
filled with a horizontally stratified red clay, containing angular and
rolled pebbles of limestone, and a few sandstone pebbles from the
Millstone Grit and Yoredale rocks. There were also a few pebbles
of white vein-quartz and of quartzite. Scattered through the mass
were mammalian bones and teeth, some water-worn and others
with sharp fractures. The contents had been clearly introduced
into the cave by water, flowing under geographical conditions
which no longer exist.
The mammalian remains belong to the following species :—
Machairodus crenatidens, Fabr. Rhinoceros etruscus, Fale.
Hyena, sp. Equus stenonis, Nesli.
Mastodon arvernensis, Croiz. & Job. Cervus etueriarum, Croiz. & Job.
Elephas meridionalis, Nesli.
All these species are found in the Upper Pliocene deposits of
France and Italy, and undoubtedly belong to that age. The
Mastodon, elephant, rhinoceros, and horse occur also in Britain in
the Upper Pliocene deposits of the Crag.
Some of the bones present the characteristic teeth-marks of the
hyeenas; and the preponderance of the remains of the young over
the adult mastodons points to the selection by the hyznas, who
could easily master the calves, while they did not as a rule attack
the large and formidable adults. The author has observed a similar
selection in the case of mammoths in hyena-dens, into which the
remains had been brought by those cave-haunting animals. He
Correspondence—Howard Fox. 93,
therefore concludes that the animal remains have been washed out
of a hyana-den, which then existed at a higher level, and carried
down deep into the rock, into the cave in which they were found,
along with the clay and pebbles brought down in flood-time from
the Yoredale and Millstone Grit hills.
The area of the Victory Quarry must then have been at the
bottom of a valley, instead of in its present position on the divide.
The denudation of the limestone which has taken place since that
time is estimated at not less than 330 feet—an amount sufficient to
destroy the ravine formed by the stream above the bone-cave, and
all the caves and rock-shelters in the district, which were accessible
to the Upper Pliocene mammalia.
The author appends a map illustrating the physical geography
of the British Isles in Upper Pliocene time. In it the British area
is represented as joined to the Continent by a barrier of land, ex-
tending from the Straits of Dover, westward, as far as the 100 fathom
line in the Atlantic, which sweeps southward from Scandinavia, off
the West of Ireland, into the Bay of Biscay. There were then no
physical barriers to forbid the migration of Machairodus, Mastodon,
Elephas meridionalis, and the rest, from Central and Southern France
into Britain. They could find their way freely from the valleys of
the Loire and the Garonne, across the valley now occupied by the
English Channel, into England and, it may be added, Ireland. Over
this area the animals migrated in the Upper Pliocene age. The
discovery of a few of them in Derbyshire is to be looked upon as
a monument of their former existence over the whole of this region.
It is also a striking example of the great destruction of the surface
which has taken place since that time, and of the imperfection of the
geological record. It is the only cave in Hurope that has yielded
remains of the remote Pliocene Epoch.
COREE Ss] @ ANS Dien Ce -Bae
PTERASPIS IN NORTH CORNWALL.
Srr,—In Dr. H. Woodward’s description of Homalonotus Barratti,
n.sp., in your last number he mentions that I recorded the occurrence
of Pteraspis at Trevone in a paper which appeared in your Macazrng,
Dec. IV, Vol. VII, p. 146. This error happened owing to a stupid
oversight of my own. I did find a portion of a Ganoid fish in the
blue shales of Trevone which was recognized by Dr. Smith
Woodward as undoubtedly Devonian, and belonging to a genus
not yet described. Specimens of the same form, he said, were in
the late Mr. Pengelly’s collection. The plate showed the internal
structure and the surface was ornamented with small bosses, but he
said it was distinct from Steganodictyum (Pteraspis), Ray Lankester.
In my table showing the Distribution of Fossils on the North
Coast of Cornwall, south of the Camel, published in the Transactions
of the Royal Geological Society of Cornwall, 1901, vol. xii, part 7,
Pieraspis is not recorded north of Bedruthan.
94 Correspondence—J. W. Spencer—G. W. Lamplugh.
Since this table was published I have obtained from Bedruthan
a slab on which there are fragments of Pteroconus mirus, and another
organism of which Dr. Smith Woodward writes: ‘I think the
reticulated piece belongs to Pteraspis, but it would have been more
satisfactory to find the outer striated layer.” Howarp Fox.
Fatmoutn, January 5th, 1903.
THE GEOLOGY OF BARBADOS.
Sir,—My extended acquaintance with the geology of Barbados
has led me to concur fully in the last paragraph of the recent article
on the subject by Professor Harrison and Mr. Jukes-Browne, and
especially in the admission of these authors that “fresh observations
are required.” For some weeks prior to the appearance of the
article, indeed, I had been in correspondence with one of the authors
of the article, who proposed a joint re-examination of the ground ;
I immediately accepted the suggestion, and began planning another
trip to Barbados with the object of demonstrating my observations
on the ground, and, if practicable, making additional collections of
fossils; and I had hoped that public discussion would be withheld
pending this appeal to the court of field observation. In view of
the prospective meeting on the ground, I am content to withhold
- detailed criticism of the article in question, and especially of the
restricted view taken by the authors, who seem satisfied to discuss
the geological history of a single spot in a great province without
reference to the records presented by other portions of the same
province. I am confident that the joint work on the ground will
enable me to present this broader view, as well as the local details,
more successfully than I have been able to do in print. ‘In the
meantime” I venture to hope that readers will ‘suspend their
judgment on the questions raised” by the paper of Prof. Harrison
and Mr. Jukes-Browne. J. W. SpPEncer.
Wasuineton, December 19th, 1902.
CLASSIFICATION OF THE LOWER CHALK OF NORTH GERMANY.
Sir,—There is a curious error in the Short Notice of Dr. A. von
Koenen’s paper ‘‘ Ueber die Gliederung der norddeutschen Unteren
Kreide” in your December number. The reviewer implies that
the result of the learned author’s revised classification is to regard
the Aptien, Barrémien, Hauterivien, and Valanginien as subdivisions
of the Albien!
We know that the German Albien is sufficiently comprehensive ;
but it has not yet been stretched to this extent. It is merely that
your reviewer, in his innocence, has been misled by finding the
Albien standing a little apart in its place at the head of the column
of ‘stages’ ! G. W. Lampnvues.
14, Hume Srreer, Dupin.
TELMATOSAURUS, NEW NAME FOR THE DINOSAUR
LIMNOSAURUS.
Sir,—Professor G. B. Fletcher has had the great kindness to inform
me that the name Limnosaurus, which I proposed in 1899 for a new
Oorrespondence—F. Nopcsa—A. Harker—S. 8S. Buckman. 98
Dinosaurian, was preoccupied by Marsh for a crocodile (1871).
I therefore propose to name the Dinosaur mentioned (Nopesa,
Denkschriften R. Akad. Wissensch. Wien, 1899) Te~marosaurus.
Baron F. Norcsa, Jun.
VienNA, January 11th, 1903. x
GRANITE AND QUARTZ-VEINS.
Sir,—The paper by Mr. J. Lomas on “Quartz Dykes near
Foxdale, Isle of Man,” which appears in your January number
(p. 34), raises an interesting question, and presents the argument
in a cogent form. There can be no doubt that, on the fringe of
a granite intrusion and in its apophyses, we sometimes find a gradual
transition from normal granite, through various rocks which may
be termed pegmatite, greisen, etc., to pure vein-quartz. Some
phases of this transition are especially well displayed at Foxdale,
a locality which I have already cited in this connection (Q.J.G.S.,
1895, vol. li, pp. 148, 144), and which has now been described in
detail by Mr. Lomas.
Closer inquiry is, however, necessary before we can be warranted
in regarding such quartz-veins as igneous rocks in the ordinary
sense. There are many indications, both from the geological and
from the petrographical side, that the more siliceous products in
question, and especially the pure quartz-veins, belong at most to
the waning stage of igneous activity, when the temperature had
fallen and the agency of water had become a more important factor.
Dr. Sorby’s well-known researches on fluid cavities, for instance,
strongly support this view (Q.J.G.S., 1858, vol. xiv, pp. 471-475).
But, further, there is sometimes reason to believe that, in these
highly quartzose fringes and veins in very intimate .connection
with granite, a considerable part of the quartz has replaced felspar,
and is therefore not strictly a primary mineral. One very clear
example among others was described some years ago by Mr. Marr
and myself on the edge of the Shap granite (Q.J.G.S., 1891,
vol. xlvii, p. 285). Here distinct pseudomorphs of quartz after
felspar put the question beyond doubt. In the greisens of Cornwall
and Saxony, the beresite of the Urals, and such peculiar rocks as
luxulyanite and trowlesworthite, the occurrence of special ‘ pneu-
matolytic’ minerals like tin-stone, topaz, tourmaline, and fluor is
equally convincing. We must recognize the possibility of a like
origin for veins of quartz, or of quartz and mica, even where no
direct evidence of replacement is preserved ; and the existence of
an igneous magma composed of pure, or nearly pure, silica cannot
as yet be regarded as proved. ALFRED Harker.
Sr. Jonn’s CotLteGE, CAMBRIDGE.
January 17th, 1903.
THE TERM ‘HEMERA.’
Str,—Mr. Jukes-Browne seems to be haunted by the good word
‘ stratigraphical.’ In the January number he finds fault with my
96 Obituary— Alfred R. C. Selwyn.
table! where certain strata are numbered to show their dates with
regard to a column of hemera affixed. This he declares makes
hemera a stratigraphical unit! Does he mean to say that in an
ordinary calendar, when one has “Jan. 15 AB died; Jan. 16 YZ
died,” that thereby Jan. 15, 16 become, not time-units, not chrono-
logical indicators of the sequence, but the numbers of the tombs.
wherein the people are buried ?
He takes another table, p. 519, ‘Correlation of Zones and
Hemerz,” and says that that shows the hemere to be parts of
a zone. In a diary one shows the correlation between certain
events and certain days of the week. Does that make the days
of the week parts of the events? The making of a piece of railway
embankment by the deposit of so much earth is set down as
occupying Monday and Tuesday; does that make these two days
parts of a railway embankment? According to Mr. Jukes-Browne
it does. A hemera (that is, Monday) is part of a zone (that is, the
railway embankment) —so he says of a geological diary.
Having come to this remarkable conclusion he declares it is my
fault that people supposed hemera was used in a stratigraphical
sense, in spite of my distinct assertions to the contrary. Now I do
begin to see how it is that people use terms incorreetly—they do not
test them by expressions of every-day life. But that is their fault,
not mine. S. S. Buckman.
OSes PASE a=
ALFRED R. C. SELWYN, C.M.G., LL.D., F.R.S., F.G.S.
Born 1n 1824, Diep Novempsr, 1902.
By the death of this distinguished geologist, Canada has lost one
of her leading men of science. Dr. Selwyn was associated with
the Geological Survey of Great Britain from 1845 to 1852. In
1853 he was appointed by the Colonial Office Director of the
Geological Survey of Victoria, Australia, a post which he held until
1869, when he retired owing to the Victorian Government refusing
to vote the supplies necessary to carry on the work. Returning to
England, on the retirement of Sir William Logan, Selwyn was at
once appointed Director of the Canadian Geological Survey, a post
which he held with distinction from 1869 to 1894, a period of
25 years, when he retired after 48 years of active and varied service,
such as few men can lay claim to have seen, in three different and
very distant quarters of the globe.
On his retirement he took up his residence in Vancouver, British
Columbia, where for the past eight years he had enjoyed a well-earned
leisure, dying at the age of 78 years. His life, accompanied by
an excellent portrait, appeared in the Gronogican Magazine for
February, 1899 (Dec. IV, Vol. VI, pp. 49-55, Pl. II). (See also
Daily Chronicle, November 8th, 1902.) H. W.
1 Quart. Journ. Geol. Soc., vol. xlix, facing p. 514.
THE
GEOLOGICAL MAGAZINE.
NEW? SERIES: DECADE “IV.5 VOEU X.
No. III.— MARCH, 1903.
@iEs GaN Awan Ace anes @ aan Se
——.—_—
I.—On some Fosstn Prawns FROM THE OsspoRNE BEDS OF THE
TIstE oF WIGHT.
By Henry Woopwarp, LL.D., F.R.S., F.G.S.
(PLATE Y.)
f{\HROUGH the intervention of my friend Mr. William Whitaker,
E.R.S., I, some time ago, received from Mr. G. W. Colenutt,
F.G.8., of Hanway Lodge, Ryde, Isle of Wight, 26 small slabs
of Osborne clay, on which are preserved, in a more or less good
state (generally less), a series of prawns and small shrimp-like
Crustaceans, collected by him from the Oligocene strata, Chapelcorner
Copse, between King’s Quay and Wootton Creek, just to the west
of the Boat-house, on the shore below Binstead House; also on the
shore below Ryde House, and immediately to the south-east of
Sea View Pier; where (especially at Chapelcorner Copse) extremely
interesting exposures of the Osborne Beds may be seen and studied,
between the base of the cliff and low-water mark (see p. 99).
These beds formed the subject of a paper by Mr. Colenutt (see
Gro. Mae., 1888, Dec. III, Vol. V, p. 858) ; while the small fishes
(Clupea vectensis) which occur associated with the Crustaceans were
described and figured in 1889 by Mr. E. T. Newton, F.RB.S., F.G.S.,
in the Quarterly Journal of the Geological Society (vol. xlv,
pp. 112-117, pl. iv).
Since receiving the above specimens from Mr. Colenutt, I have
been favoured with three additional examples, also obtained from
King’s Quay, by Mr. Reginald W. Hooley, of Ashton Lodge,
Portswood, Southampton, who has paid considerable attention to
the fossils of the Tertiaries of Hampshire and the Isle of Wight.
The entire series comprises fourteen examples of the larger form
(see Pl. V, Figs. 1-4) and fifteen of the smaller one (PI. V, Figs. 5-7),
Figs. 1 and 4 of the former having been drawn from Mr. Colenutt’s
and Figs. 2 and 3 from Mr. R. W. Hooley’s cabinet. The smaller
form (Figs. 5-7) is from Mr. G. W. Colenutt’s Museum.
DECADE IV.—VOL. X.—NO. III.
=
d
98 Dr. H. Woodward—Fossil Prawns from the Isle of Wight.
Owing to the presence of orbicular calcite and some iron pyrites
in the clay, it is often very difficult to detect the details of the
structure of these Crustaceans ; moreover, in order to preserve them
from decay, they have to be treated with a coat of hot gelatine,
which, although preservative, is apt to obscure minute details of
structure afterwards.
PropaLzZmon Ossorniensis, H. Woodw. (PI. V, Figs. 1-4.)
Although there is no one example of the large Osborne shrimp
which has been preserved entire, nevertheless, by a careful exami-
nation of the fourteen specimens before me, I am enabled to arrive at
a fairly correct notion of the separate parts, and so of the prawn as
a whole. .
The general outline of its form may be seen from the examples
figured on Pl. V, Figs. 1-4, but no restoration has been attempted.
From Fig. 1 we perceive that the carapace measures 20 milli-
metres in length (the rostrum in this specimen is injured and
indistinct, but is better seen in Fig. 2); the depth of the carapace in
profile is 11 mm.; the abdomen (‘pleonic somites,’ Bate) measures
28mm. in length, minus the telson, which, although wanting in
Fig. 1, is supplied by Fig. 3, and is 10mm. long; the lateral
lobes of the tail-fin being about equal in length, or a trifle longer
than the telson. In Fig. 2 the rostrum shows five distinct teeth or
serrations; a single spine is also to be observed on the hepatic
region of the carapace in Figs. 2 and 4; the bifid flagella of the
inner antenne are preserved in Figs. 1 and 2, but the fragmentary
remains of the long outer antenne are only imperfectly seen on
some of the slabs ; the long slender ambulatory legs measure 25 mm.,
they are shown in Figs. 2 and 4. But the first and second long
and slender chelate limbs are too imperfectly preserved to be made
out satisfactorily, though I believe both of them to be present. The
abdominal swimming feet (pleopods) are well preserved in Figs. 1
and 2, and are about 12 mm. in length. The pedunculated eye can
be seen in Fig. 2 and also in Fig. 4.
In size this prawn closely agrees with the living Palemon affinis,
M. Edw.' (PI. V, Fig. 8), but the rostrum in the living form is
considerably larger and more strongly serrated, both above and
below. The segments of the abdomen (pleon) in the fossil form
closely resemble the living genus, but the pleopods are perhaps
somewhat longer in the Osborne specimen.
Having regard to the difficulties of dealing strictly with such
imperfect material, I venture to define the fossil form as Propalemon,
and for a trivial name I have called it after its locality, Osborniensis.
PropaLwMmon minor, H. Woodw. (PI. V, Figs. 5-7.)
™ This little form, of which fifteen examples have been obtained by
Mr. Colenutt, from the same beds as have yielded the larger species
(P. Osborniensis), measures 26 mm. in length (of which the carapace
measures 10mm., the pleon 11 mm., and the telson 5mm. The
1 Fie, 8 is drawn in our Plate of twice the natural size.
ci
Geol Mag 1903. ; Decade IV Vol. X.PIV.
5 * 7
GM. Woodward del.et lith. West,Newman imp.
Tings at Fossil Prawns &¢.,O0sborne Beds, l.of Wight. +.
Fig.8.Palemon affinis, MKdw (recent ) 7.
G. W. Colenutt—Note on the Osborne Beds. 99
depth of the carapace is 5mm., and the pleon at the third somite is
of the same depth. The appendages are not preserved, nor can the
serrations on the rostrum be clearly detected.
This may possibly be a young form of the larger species with
which it is found associated, but of that we have no~ positive
evidence before us; it is therefore most convenient to treat it as
distinct. Both species occur pretty abundantly in the same bed
which yielded the small Clupea vectensis, described by Mr. H. T.
Newton, F.R.S., and are in all probability either estuarine or
marine. The living Palemonide occur, not only in the sea, but
also in rivers, in Lake Amatitlan Guatemala, the islands of the
Pacific, and one in Australia, Palemon affinis, Pl. V, Fig. 8 (see
“Voyage of Challenger”; Crustacea, by C. Spence Bate, 1888,
vol. xxiv, p. 782, pl. cxxviii, fig. 5). Two genera are British.
In this genus (Palzmon) the most striking feature is the elong-
ation of the second legs in the male, which not infrequently even
exceed the total length of the animal’s body ; a specimen of Palemon
lar may measure about five inches from the front margin of the
carapace to the tip of the telson, and carry limbs eight inches long.
(See “A History of Crustacea,” by Rev. T. R. R. Stebbing, F.R.S.,
pp. 246-247.)
The following account (Art. II) of the geology of a portion of
the Osborne Beds of the Isle of Wight, whence the fossil Crustacea
were obtained, has been most obligingly drawn up for me by
Mr. G. W. Colenutt, F.G.S., the first discoverer of the fossils.
EXPLANATION OF PLATE V.
Fies. 1-4.—Propalemon Osborniensis, H. Woodw. Osborne Beds: Isle of Wight.
Fries. 5-7.—Propalemon minor, H. Woodw. Osborne Beds: Isle of Wight.
Fic. 8.—Palemon affinis, M. Edw. Recent: Port Jackson, Sydney, New South
Wales.
II.—Novre on THE GEOLOGY OF THE OsBORNE Beps.!
By G. W. Cotzenurt, F.G.S.
A ie fossil shrimps or prawns briefly described in the preceding
paper by Dr. H. Woodward occur in the ‘fish-clay’ of the
Osborne Series at Chapelcorner Copse, Binstead House, Ryde House,
and Sea View, Isle of Wight, and they were first discovered by me in
these beds about the year 1876. Having regard to the fact that
new species of fish, etc., have been recently obtained from the
Osborne Beds, it would seem that these prawns are very probably
also new to English strata.
At nearly all outcrops of these beds the strata yield few fossils,
" The following is a list of the papers bearing on the present article :—
G. W. Colenutt, ‘‘On the Osborne Beds’’: Grou. Mac., 1888, p. 358.
E. T. Newton, ‘(On Clupea vectensis’?: Q.J.G.8., February, 1889, vol. xliv,
pp. 112-117, pl. iv.
E. T. Newton, ‘‘ Geology of the Isle of Wight’’?: Memoirs of Geological Survey,
1889, p. 152 et seq.
E. T. Newton, ‘On Amia”’: Q.J.G.S., February, 1899, vol. lv, pp. 1-10, pl. i.
G. W. Colenutt, ‘‘ Notes on Geology of the North-East Coast of Isle of Wight”? :
Papers and Proceedings of the Hampshire Field Club for 1891.
100 G. W. Colenutt—Note on the Osborne Beds.
but there are some eight or ten feet (vertical measurement) of strata
at the base of the upper division of the series (the St. Helen’s
Sands of Forbes) which are rich in fossils in some localities. In
consequence of the soft nature of the clays, retaining or sea walls
have been built nearly all the way from Ryde to Sea View, and,
unfortunately, as it is here found, generally speaking, a short
distance above or about high-water mark the fossiliferous band is
obscured by the walls, the outcrop, roughly speaking, being about
horizontal between the two places. Only four localities where these
beds can be examined are at present known, namely, at Sea View
(here often covered up by sand and shingle), at Ryde House (now
mostly obscured by an old ‘founder’ of the low cliff), at Binstead
House (an imperfect exposure), and at Chapelcorner Copse, just
west of Wootton Creek. This last is by far the best section, and
we will take it as representing the others.
The ledge of rocks just above low-water mark is the limestone of
the Osborne Series, forming the topmost division of the ‘ Nettlestone
Grits’ of Forbes ; and tracing the strata in ascending order from this
base we have the following series of beds :—
, A 5 Z
oS j
m7 2
osu
Section showing the succession of the Osborne Series from the Osborne Limestone at
the base to the Bembridge Limestone at the top. (Fig. 4 of this section is the
bed which has yielded the small Clupea vectensis and the Crustaceans described
by Dr. H. Woodward.)
Vertical Estimated Measurements.
1. (Bed 6 in my paper, Grou. Mac., 1888, p. 359.) Dense clay,
green and brown mottled, about 4 feet; no fossils whatever, as far
as I am aware.
2. (Bed 5 in my paper, op. cit.) A series of clays of fluviatile
origin, about 6 feet. At the base is a dark blue or blackish seam,
about 2 inches thick, of finely comminuted shells mixed with
carbonaceous clayey particles. This seam has yielded bones of
Trionyx, teeth, etc., of Alligator Hantoniensis, bones of Amia Anglica
(vide Mr. Newton’s paper), also the jaw of Amia Colenutti, scales of
G. W. Colenutt—Note on the Osborne Beds. 101
Lepidosteus, many small fish- bones, vertebra, etc.; and in this
seam I have also noticed small dark blue or green pebbles,
apparently of flint. The shells are probably Paludina lenta and
Melanopsis carinata, but are almost too crushed to be identified.
There is above this most interesting seam about three feet of rather
hard stratified dark blue clay, with many seams of P. lenta and
M. carinata, mostly crushed, but some perfect, with occasional masses
of iron pyrites encrusting the shells, and also some lenticular
masses of grey cement-stone. ;
3. (Bed 4 in my paper, op. cit.) The clay slightly alters, fewer
seams of shells being observed, but at the top of this division, which
may be about 3 feet thick, we find many vegetable remains matted
together. These are mostly of reeds or sedges, but are not yet.
identified; occasionally one may find carbonized seed-vessels
resembling Folliculites thalictroides, but somewhat different in shape,
also some much smailer oval seeds; flat leaves of reeds or water
plants with roots and rootlets attached, somewhat resembling the
living Zostera, occur abundantly. Ali these plant remains are
associated with Paludina and Melanopsis, and are in layers in
a somewhat soft grey clay ; it is difficult to preserve the plants, as
they crack and curl up on drying. Lenticular masses of cement-
stone also occur in this division.
4, (Bed 3 in my paper, op. cit.) Immediately above the plant bed
occurs the ‘fish-clay.’ This is a seam of dense, dark greenish grey
clay about 7 inches thick, very distinct in character from any of
the other clays. It acquires a lighter colour on drying, and when
dry assumes a somewhat granulated surface. It is a continuous
seam, judging from its appearance at the several sections. It has
not been found west of King’s Quay, nor is it seen at Whitecliff Bay.
The clay has an irregular transverse jointing, and readily separates
into rough nodules. It is highly laminated, and easily flakes when
split with the point of a knife; it is about as hard as ordinary yellow
soap. It is much charged with iron pyrites, in the form of dark
gritty masses or lumps in the clay. Clupea vectensis and the prawns
are found distributed in this seam; the top half-inch of the bed is
the best place, however, in which to look for them. The fish are
generally in small shoals, but the prawns are usually solitary,
though the smaller ones do occur in shoals. No insect remains have
as yet been observed.
5. (Bed 2 in my paper, op. cit.) Above the fish bed are several
feet of green, brown, and grey clays, of a flaky nature, and on one
horizon thin lenticular masses of fish bones, etc., occur. These
deposits have yielded remains of Lepidosteus (vertebre, scales, and
bones), snake vertebre, jaws and vertebra of Amia Anglica, teeth of
Theridomys, Paleotherium, A. Hantoniensis, bones of Hmys and
Trionyx, and quantities of bones and vertebra of teleostean fish,
etc. These are obtained, of course, by drying, scalding, and washing
the clay.
6. (Bed 1 in my paper, op. cit.) Above this is about 40 feet or so
of the usual mottled unfossiliferous green, red, brown, grey, and
102 Rev. R. A. Bullen—Eoliths from 8S. & S.W. England.
yellow clays of the Osborne Series, capped at the top of the cliff
by the Bembridge Limestone.
Judging from the character of the fossils, we seem to be justified
in coming to the conclusion that Nos. 1, 2, and 3 were deposited in
an estuary, or in a lake, or lagoon near the sea; the mollusca are
fluviatile, and so are the vertebrate remains. At the top of No. 3
we have evidences of much plant growth, pointing to a calm lagoon,
in which deposition was slow and regular. The fish-clay is puzzling,
and we shall probably not be far wrong in assuming that a sudden
influx of marine mud caused its deposition. The Clupee are most
probably marine forms, and all the fish appear to have been
smothered or asphyxiated, as the jaws are wide open and the fish
are quite perfect. It remains to be seen whether the prawns are
marine or fluviatile forms. Above the fish-clay we find that the
Paludine, ete., disappear, pointing to much more brackish conditions ;
the lenticular masses of bones suggest drifting and the influence
of deeper water, while further up the mottled red clays decidedly
indicate semi-marine conditions of deposition.
In a local series like the Osborne Beds it is not surprising that
new forms should be found, especially in a deposit which varies so
much in its different outcrops.
IlI].—Houirus From Soutru anp Soutu-West ENGLAND.
By the Rev. R. Asuineron Buien, B.A. Lond., F.G.S.
(PLATES VI, VII, AND VIII.)
I. Introduction.
II. Character of the Eoliths.
III. Researches of Blackmore, Westlake, and C. Reid.
IV. Kolithic Localities in the Drainage Area of the Avon.
V. The Dewlish Implements.
VI. Use of Hollow ‘ Scrapers.’
VII. Description of Specimens figured.
VIII. Bibliography.
I. Introduction.
HE labours of Mr. Benjamin Harrison around Ightham, in Kent,
have been before the scientific world since May, 1889, when
Sir Joseph Prestwich read his now historic paper before the
Geological Society ‘‘On the occurrence of Paleolithic Flint Imple-
ments in the neighbourhood of Ightham, Kent ; their distribution and
probable age.”
This was followed in 1891 by an even more important one, ‘On
the Drift Series of the Valley of the Darent, with remarks on the
Paleolithic Implements of the district, etc.,” also read before the
Geological Society.'. In this masterly memoir he gave the results
of his long and careful examination of, more particularly, Mr. B.
Harrison’s collection of flint implements from the neighbourhood
of Ightham, their distribution and probable age.
1 Published in the Quart. Journ. Geol. Soc., 1891, vol. xlvii, pp. 126-163.
Rev. R. A. Bullen—Eoliths from S. & S.W. England. 108
On the gravelly soils, and in the gravels of certain areas of the
Chalk Plateau above Ightham, have been found some deeply stained
implements, of either the same kind as those of St. Acheul or those
of Chelles in France, “for the most part of oval or ovate Hones; but
not unfrequently pointed.” *
M. Mortillet regarded this gravel at Chelles as a high- steel river-
drift, equal to the oldest of St. Acheul (see also C. H. Read’s “‘ Guide
to the Antiquities of the Stone Age,” British Museum, 1902, p. 9).
It may be noticed that two of these ovoidal implements from the
Chalk Plateau are figured by Professor Prestwich in his ‘‘ Contro-
verted Questions, etc.,” 1895, pl. xi, figs. 38 and 39, which are
referred to by him as being of the St. Acheul type, but either shaped
by the same people that made the plateau specimens, by individual
progress in the art of shaping tools, or probably by some later valley
folk passing over the hills and dropping their weapons and tools
p:. 64).?
Associated with these implements there occur very abundantly
on the Chalk Plateau, as carefully exploited by Mr. B. Harrison,
other flints of definite shapes, and deeply coloured, known as
‘eoliths’ and ‘old brownies,’ which have been subject to much
diversity of opinion among some, especially inexperienced observers.
In certain localities, these probably earlier implements occur
without being associated with the large ovate forms.
II. Character of the Holiths.
The general features of the eoliths,? as we shall continue to
designate these ruder and earlier forms, are well marked and
distinct.
They are made of flint flakes (sometimes tabular), probably broken
off by natural forces, but some are formed of split Hocene pebbles.
They rarely show the bulb of percussion. Advantage has been
taken by the original worker of natural curves, concave or convex,
and these have been modified by well-defined small flakings. In
some cases smaller flakes have modified these; in many instances
the edges have been further modified by local pressure being used
(which we may distinguish as abrasion), or in other cases the edge
has been rubbed and rounded by contusion with other flints in the
ordinary course of trituration or wearing away by rolling in a river
bed, or in a rough downward passage from higher to lower ground.
The edges of many of the eoliths discovered by Dr. Blackmore in
Wiltshire are quite sharp, and cannot have travelled far. I have
also one from Hinton Admiral Common, Hants, and another from
1 Evans: ‘‘ Ancient Stone Implements,’’ 1897, 2nd ed., p. 608.
2 T have in my collection one such deeply stained ochreous specimen from Currie
Farm, Kent (fig. 6 of pl. xxi, Prestwich, ‘‘ Primitive Characters, etc.,’’ p. 246). Two
others, one ov ate (St. Acheul type), and the other (referred to by Prestwich, ‘* Drift
Stages, ete.,’’ p. 133) of the sharp-pointed high-level type, with massive butt (tip
broken off), are both white and patinated, and are the implements referred to in
the text.
3 They have been termed ‘ plateauliths ’ by Mr. Lewis Abbott.
104 Rev. R. A. Bullen—Eoliths from 8S. & S.W. England.
Well Hill, Kent, whose edges are almost or quite free from
contusion.
We are now in a better position thus to define the eoliths through
Dr. H. P. Blackmore’s work at Alderbury during many years. In
that deposit at 325 feet O.D., about 3 miles south-east of Salisbury,
no paleoliths of accepted type have been discovered, a fact which
demonstrates to my mind the later age of some of the more or less
ochreous implements of Paleolithic types from the Chalk Plateau
of Kent. Thus the Pre-Glacial plateau specimens are divisible into
two periods, although Prestwich in his two papers classed them all
_as paleoliths, and in Professor Rupert Jones’ opinion this mixture
of early Paleolithic and Holithic types only shows that man varied
his work.
Some Paleolithic implements from the Kent plateau with a porcel-
laneous lustre have also occurred as surface finds near Bower Lane,
Hynesford. These belong to a later epoch, and seem to have been
dropped by Paleolithic hunters on the surface and to have been
bleached by contact with the clay. The alumina of the clay
undoubtedly has this bleaching action, and even softens the flints by
extracting the water of crystallization, either as they rested or were
slightly embedded in it. This also seems to have been the case of
Prestwich’s porcellaneous Downton implement quoted by Mr. C.
Reid, which occurred at a level to which in age it does not apparently
belong.? However, the fact remains that from the gravel deposit at
Bat’s Corner, Kent (the British Association pit excavated by Mr. B.
Harrison, 1894, the geological age of which is somewhat uncertain,
but probably pre-Glacial), and from the pit at Alderbury worked so
assiduously by Dr. H. P. Blackmore (the age of which, from the
occurrence of Pecten asper and other Gault and Upper Greensand
fossils, is that of the Southern Drift), the implements of Paleolithic
type are wanting, and the EKoliths wrought and used by man only
occur. These are either ‘straight sleekers,’ ‘round sleekers,’ or
‘hollow scrapers,’ certain of them with the point somewhat like
a bird’s beak, which characteristic form Dr. Blackmore considers
especially belongs to implements of the Holithic epoch.
As this bird-beak point occurs in not a few definite paleoliths
(Dr. Blackmore has several in the Museum at Salisbury), and the
hollow curve in not a few others (the latter notably in those from
the newly discovered Knowle Pit, Savernake), we seem to be
arriving at some steps in the evolution of the paleolith.
1 This specimen, found close to the 500 feet contour, may have been made near
the spot where found. Professor Rupert Jones, however, from the point of view
of the denudation of the Weald, suggests that implements belonging to the Southern
Drift, moving downward along the slopes of the Old Wealden Heights, and enclosed
in mud or clay, might travel a considerable distance without being subject to
contusion.
? Bullen, ‘‘ Kolithic Implements’’: Trans. Victoria Institute, 1901, vol. xxxiii,
p- 196.
3 «*Geol. of Country round Ringwood,’’ p. 36. The specimen is preserved in
the Prestwich Collection in the Geological Gallery of the British Museum (Natural
History), in the tenth drawer, left-hand tier.
Rev. R. A. Bullen—FEoliths from 8S. & S.W. England. 105
II]. Researches of Messrs. Blackmore, EH. Westlake, and
Clement Reid.
Mr. E. Westlake, F.G.S., is now in the rank of workers on the
Eolithic question, and both he and Dr. Blackmore have kindly placed
their records from the Plateau terraces (or ‘ plains’) of the Ring-
wood area at my service in writing this paper. With two such
trained and enthusiastic workers on the spot our knowledge ought
to advance rapidly.
From 1898, when Dr. Blackmore found an eolith in gravel on the
ridge at Woodfalls, near Redlynch, to the present year,’ a sufficient
number of eoliths have been found by both the two above-named
workers to constitute the Plateau gravels of the Ringwood district
effective witnesses for the existence of man at a less advanced stage
of progress as to the manufacture of stone implements—lower,
i.e., than in the next or Paleolithic stages of human culture. For
these Plateau gravels are the highest in the New Forest district.
Mr. Westlake states :2 ‘‘On November 4th, 1902, I found several
examples of eoliths in the east pit on Black Bush Plain, at a height
of about 410 feet O.D., or 310 feet above the Avon at Breamore.
This gravel caps the highest ground between Fordingbridge and
Southampton ; and, beyond having a slight slope towards the Solent,
has no obvious relation with any of the surrounding valleys. The
flatness of the plain and the much rolled and battered character of
the gravel, I think, point more to the marine origin suggested by
Mr. Codrington (1870) than to the river origin suggested by
Mr. Reid (1902). . . . . There can be no auestion as to the
position and antiquity of the gravel.”
Mr. Clement Reid has seemingly good reasou for his reference to
river action, at least in contributing materials for the gravels, in the
fact that Jurassic rocks (silicified Purbeck Limestone) occur in the
Plateau gravels at 386 feet O.D. near Picket Corner.®
As the present paper, however, is rather simple in its scope, the
intention being to put on record the occurrence of Holiths among the
Plateau gravels, we leave the existence or not of a Solent river to
the evidences for which, pro and con., Mr. Reid refers* in a useful
footnote. He is to be congratulated on breaking free from the usual
prejudice and tradition about man’s geological age, and on accepting
and incorporating, in a memoir issued by the Geological Survey,
the long-despised and suspected Holith.
But in one small particular the “‘ Diagram of the Terraces of the
Avon” (fig. 4, p. 34, op. cit.) needs reorganizing, for the researches
and ‘finds’ of Dr. H. P. Blackmore (1898-1902), of Mr. E. Westlake
1 The writer had previously found hollow curved scrapers at the summit of Alum
Chine and on Hinton Admiral Common in May, 1895, and a derived specimen at
Jumper’s Heath in November, 1893. These were shown to and approved by the late
Sir Joseph Prestwich in 1893 and 1895 respectively.
2 “ Antiquity of Man in Hampshire,”’ last page. King’s Fordingbridge Almanac,
1903. An eolith from White Shoot Farm is figured in the text.
3 C. Reid: ‘* Geol. of Country round Ringwood,”’ p. 30.
4 Op. cit., p. 32, note.
106 Rev. R. A. Bullen—Eoliths from 8S. & S.W. England.
(1902), and of myself (1895) establish the Holith in the proud
position of occupying the high plateau above the 400 feet contour,
or its equivalent further to the south. (See Sheets 314, 329, Geol.
Survey, new 1 inch map, printed in colours.)
IV. Eolithic Localities in the Drainage Area of the Avon.
The under-mentioned localities are those represented in the
collections particularized :—
I. Dr. H. P. Buackmorge, F.G.S.1
Height above O.D.
feet.
1. Tinney Copse ahe ae 8 Boh ee 43 375
(This is the White Shoot Pit of Westlake, iufra.)
2. Deadman Hill Pit, locally known as Alderton ... staf soo GHW)
3. Hale’s Purlieu Bee sa 806 sys ON: sae ... 9860
4, Hatchett’s Green ... ee fe oe BAS Si apo) OL)
II. Mr. E. Westiaxe, F.G.S.?
Approximate height above
O.D. Avon.
feet. feet.
1. Piper’s Weight,’ about one mile north
of the last pit (locally ‘ Long Cross ’
Pit) on Black Bush Plain... bs 421 wae 321
2. Black Bush Plain aa sd is 400 303 300
3. Turf Hill Pit, south of the Downton
Road, about one mile north-west of
the Telegraph (= old Semaphore) ... 380 His 280
‘Deans White Shoot Pit, one mile south of
ak Redlynch .... a8 ie ses 375 One 265
5. Godshill Ridge Pit, marked on the 6 in.
map as Gravel Pit Hill : se 325 235
6. The eastern pit on Frogham Hill,
locally known as Abbot’s Well Pit... 260 she 180,
7. Bournemouth : Alum Chine, fallen
gravel from top of cliff Bae a 120 fe —
Paleeolithic.*
Early Palzeolithic.
Hyde Common Pit 500 b00 606 506 230 ote 150
Sandy Balls Pit... aia Sos ay: ase 240 me 150
Middle Paleolithic.
Woodgreen Pit ... 5 ale 200 : 100
It is noteworthy that all the Holithic localities examined, both
by Dr. Blackmore and Mr. Westlake, occur ata higher level than
the second terrace, 300 feet O.D. (the Holithic), in Mr. Clement Reid’s
diagram of the Terraces of the Avon,’ and that the other localities
at Alum Chine and Hinton Admiral Common are on the high plateau
further south, though at a less elevation O.D. because of the
southward slope of the plains.
1 Blackmore, in letter. 2 Westlake, in letter.
3 This is the highest point in the New Forest.
4 These lower terraces seem to correspond to those so successfully worked by
Mr. S. Hazzledine Warren, F.G.S., in the Isle of Wight (Grou. Mac., Sept. 1900,
pp- 406-410). They are inserted here merely to contrast the well-defined terraces
yielding accepted Paleolithic forms and the higher Eolithic terraces.
5 Geol. of Country round Ringwood, p. 34.
Rev. R. A. Bullen—EHoliths from 8S. & S.W. England. 107
V. Criticism of Mr. Clement Reid’s statement about the Dewlish Holiths.
In concluding this short notice J regretfully animadvert on
Mr. Reid’s statement! that the flints associated with H. meridionalis
at Dewlish are so battered that their artificial origin is open to much
doubt. The only specimen for which this statement could possibly
stand is the one numbered 15f (Bullen, ‘“ Holithic Implements,”
pl. ili, fig. 2). The others, Nos. 28, 18, 32, 51f (Dr. Blackmore’s
collection), have much less ‘batter’ than usual upon their well-
defined edges, which circumstance, to those accustomed to discriminate
between natural and artificial flaking and chipping, is of most
persuasive force. The above-mentioned stone tools are before me
as I write. Their colour, originally deeply ochreous, has been
lightened very considerably by bleaching in the sandy matrix in
which they had so long lain.
VI. Use of Hollow ‘Scrapers.’
A passage in Sir J. W. Dawson’s “‘ Modern Science in Bible Lands,”
p- 300, deserves quotation in its entirety, as it may throw light on
some, if not the majority, of the hollow ‘scrapers’ so characteristic
of Holithic workmanship, especially when we consider the prime
necessity to man of procuring fire in all stages of his civilization :—
“When in Egypt in 1844 I saw women in the market at Assiout with
baskets of flint flakes on sale. I asked the use of these, and found
they were for strike-lights. Iasked, ‘ Why do they not use matches?’
The answer was, ‘Matches are too dear for the fellaheen. It is
much cheaper to have a flint and steel, and a little fibre from the
spathe of the doum-palm to light their cigarettes.’ I afterwards
verified this by examining the tobacco-pouches of some of the people,
and exchanged with one of them a new flint for one that he had
used so long that its front had been chipped into a semicircular
form, like that of one of those hollow scrapers one sees in coilections
of stone implements, and which are supposed to have been used for
polishing shafts of spears, but some of which are possibly worn-out
strike-lights of dubious antiquity. It may be observed here that
in the most primitive times, before steel could be obtained, the
native* iron pyrite was used for the same purpose, as evidenced
by fragments of it found in very ancient burial-places and caverns
of residence.”
Iron pyrites, however, is not absolutely necessary for the procuring
of fire; the percussion of quartz and flint® produces sparks, and
probably the percussion of flint or chert with flint* would do so,
since they are all forms of silica, either crystalline or amorphous.
1 Tbid., p. 36.
2 Joly: ‘‘ Man before Metals,’’ 3rd ed., p. 196.
3 Jago, Royal Cornwall Gazette, Nov. 29, 1900: Royal Institution of Cornwall
Annual Meeting. Mr. A. Pott (of Bath) writes, ‘‘ I find I can get finer sparks from
the quartz and flint than from either with the pyrites.”’
4 An illustration of how strike-a-lights of flint, found in the Dordogne Caves,
may have been used is given in the Reliquie Agquitanice, Feb. 1870, pt. x,
pp. 138, 139, figs. 36, 37.
108 Rev. R. A. Bullen—LHoliths from S. & 8. W. England.
VII. Description of Plates.
PLATE VI.
Fic. 1.—Double-shoulder scraper, work on one face only; sub-ochreous, rather
bleached, probably by vegetable action.1 Deadman Hill, 400 feet O.D. (H.P.B.)
Fre. 2.—Similar implement from Alderbury, split pebble with drusic cavity on
reverse, slightly ochreous. Alderbury, 325 feet O.D. (H. P. B.)
Fic. 3.—Bleached, frost-bitten, double-shoulder scraper, showing greatest use on
curve of left shoulder; right shoulder produced by removal of a single flake.
Sharp edges of each curve removed by local abrasion due to use. Near Tinney
Copse, about 375 feet O.D. (H. P. B.)
Fie. 4.—Hollow curve of Upper Greensand chert, having no signs of human
use. Hale’s Purlicu, about 365 feet O.D. Source: Vale of Wardour. (C. Reid,
op. cit., p. 30.)
Fie. 5.—Rough flake from a ‘ Woolwich and Reading’ pebble made into a hollow
‘seraper’ ; edge still acute, resembling others from Alderbury ; sub-ochreous ;
bleached probably by vegetable action. Hinton Admiral Common, 110 feet O0.D.
May 28th, 1895. (R. A.B.)
Fic. 6.—Bleached hollow ‘ scraper’ just below summit of Alum Chine, much more
rolled than Fig. 5. Alum Chine, about 110 feet O.D. May, 1895. (R.A. B.)
PLATE VII.
Fre. 1.—Ochreous, hollow, beaked ‘scraper’ from Alderbury; edges of curve
sub-acute. Alderbury, 325 feet O.D. (H. P. B.)
Fie. 2.—Ochreous, hollow, beaked ‘scraper,’ sub-acute, blunted by local abrasion
through use, or contused by natural causes. Near Tinney Copse, about 375 feet
OAD Sys (EPP eB ®)
Fig. 3.—Sub-ochreous, hollow ‘scraper,’ frost-bitten, sub-acute, with a convexo-
concave surface showing work on both faces. Deadman Hill, about 360 feet O.D.
(H. P. B.
Fie. eee hollow ‘scraper,’ bleached by contact with clay or loam.
Porcellaneous on worked curve and other parts; the high patina probably
caused by the scouring of water containing sand or silt. Near Tinney Copse,
about 375 feet O.D. (H. P. B.)
Fie. 5.—Hollow ‘scraper’ with well-defined symmetric curve, showing primary
- and secondary chipping and local abrasion from use, the latter modifying the
sharp edge produced by the smaller secondary chipping. Deeply ochreous,
older than the valley gravels with which it was associated. Jumper’s Heath,
about 20 feet O.D. (R. A. B.)
MAP, PLATE VIII.
Incidentally one is inclined to discount the value of mineralogical
condition, at all events in determining the age of Holithic implements.
Taking the hollow scrapers as an example, though of the same type,
these show, even from the same deposit, e.g. Alderbury, great
differences as regards stain, hardness, patina, and wear.
In conclusion I would thank Dr. Blackmore and Mr. Westlake
for their kind co-operation, and Professor T. Rupert Jones, F.R.S.,
for helping me both in the manuscript and the proofs.
VIII. Bibliography of the subject.
1889. Prestwich, J.—‘‘On the occurrence of Paleolithic Flint Implements in the
neighbourhood of Ightham, Kent; their distribution and probable
age’’: Q.J.G.S., 1889, vol. xlv, p. 270.
1891. Prestwich, J.—‘* On the Age, Formation, and Successive Drift Stages of the
Valley of the Darent, etc.’?: Q.J.G.S., 1891, vol. xlvii, p. 126.
1 For rationale of this bleaching of flints, see Codrington on the superficial
deposits of the South of Hampshire and the Isle of Wight: Quart. Journ. Geol. Soe.,
1870, vol. xxvi, p. 528.
Peeves 03 | Decade IV-Vol PL VL
G.MWoodward del.et Lith, West,Newman inp.
Folths, om S.W ante. fnat SUKE!
Decade IV. Vol. X Pl VIL.
Gedl Mag 1902.
. 3
PV aded
West,Newman imp,
GM Woodward del. et lith.
Kolths. #om S.W fants. = Vat SULE.
GEOL. MAG. 1903. Dec. IV, Vol. X, Pl. VIII.
“Alderbury
(B) 325
(W)4/0
Ock nell * Stoney Cross
(w)365 (CA)
Hurs
Castle
wv
R
Alum Chine
(RA\B 1895)
Koliths from the Plateau-Gravels of South-West Hants, near Ringwood.
RK. Ashington Bullen.
Map showing the course of the Avon below Downton.
W., Westlake; B., Blackmore; A.A4.Z., Bullen. |The squares are each five miles.
After Bacon’s ‘‘ Popular Atlas of the British Isles,” 1902.
The localities revised by Mr, E. Westlake, F.G,S.
Rev. R. A. Bullen—Eoliths from S. & S.W. England. 109
1892. Prestwich, J.—‘‘ On the Primitive Characters of the Flint Implements of the
Chalk Plateau of Kent, with reference to the question of their Glacial
or Pre-Glacial Age’’ ; with Notes by Messrs. B. Harrison and De Barri
Crawshay: Journ. Anthrop. Institute, 1892, vol. xxi, p. 246.
1893. Laing, S.—‘‘ Human Origins,”’ p. 287 ; 10th thousand ; London, 1893.
1894. Abbott, W. J. Lewis.—© piatenn Man in Kent??: Nat. ScieBee, 1894,
vol. iv, p. 257.
Bell, A. M.—* Remarks on the Flint Implements from the Chalk Plateau
of Kent??: Journ. Anthrop. Inst., 1894, vol. xxiii, p. 268.
Jones, T. Rupert.—‘‘ On the Geology of the Plateau Implements of Kent’’:
Nat. Science, 1894, vol. v, p. 269.
_ Shrubsole, O. A.—‘* Flint Implements of a Primitive Type from Old (Pre-
Glacial) Hill Gravels in Berkshire’’: Journ. Anthrop. Inst., 1894,
vol. xxiv, p. 44.
1896. Prestwich, J.—‘‘On some Controverted Questions of Geology,”? p. 49;
London, 1896.
Salter, A. H.—‘‘‘ Pebbly Gravel’ from Goring Gap to the Norfolk Coast”? :
i Proc. Geol. Assoc. ., 1896, vol. xiv, p. 389.
1897. Abbott, W. J. Lewis. — Worked Flints from the Cromer Forest Bed’’
(illustrated) : Nat. Science, 1897, vol. x, p. 89.
Abbott, W. J. Lewis.—** History of the Weald’: Trans. S.E. Union
Scient. Societies, 1897, p. 26.
Cunnington, W.—‘‘The Authenticity of Plateau Man’’: Nat. Science,
1897, vol. xi, p. 327.
Thieullen, A.—‘‘ Les Véritables Instruments usuels de ’age de la Pierre ”’ :
4to; Paris, 1897. Many specimens of KHolithic type figured besides
others.
1898. Kennard, A. Santer.—‘‘ The Authenticity of Plateau Man’’: Nat. Science,
1898, vol. xu, p. 112.
Abbott, W. J. Lewis.—‘* The Authenticity of Plateau Implements’’: Nat.
Science, 1898, vol. xii, p. 112.
Bulien, R. Ashington.—‘‘ The Authenticity of Plateau Implements’: Nat.
Science, 1898, vol. xii, p. 106, pls. iv-vil.
Bell, A. M.—‘‘ The Tale ot the Flint’’: Longman’s Magazine, Jan. 1898,
p. 214.
Cunnington, W.—‘*On some Paleolithic Implements from the Plateau
Gravels, and their Evidence concerning ‘ Kolithic’ Man’’: Q.J.G.S.,
1898, vol. liv, p. 291.
Mareh, H. C.—‘*The Twin Problems of Plateau Flint Implements and
a Glaciation South of the Thames’’: Proc. Dorset Nat. Hist. Field Club,
1898, vol. xix, p. 180. ;
Salter, A. E.—‘‘ Pebbly and other Gravels in Southern England’’: Proc.
Geol. Assoc., 1898, vol. xv, p. 264.
Jones, T. Rupert.—** Exhibition of Stone Implements from Swaziland, South
Africa’’: Journ. Anthrop. Inst., 1899, vol. xxviii, p. 52.
1899. Bird, C.—‘‘ Plateau Implements’’: South Rochester Naturalist, 1899,
vol. ii, p. 565.
Harrison, B.—‘* Plateau Implements
Societies, 1899, p. 12.
Jones, T. Rupert. “Stone Implements found in a Cave in Griqualand
Kast’’: Journ. Anthrop. Inst., 1899, vol. xxviii, pp. 255 (note) and 256.
Leith, G.—‘‘ On the Caves, Shell- Mounds, and Stone Implements of South
Africa’? : ibid., 1899, vol. XXVill, p. 258 (Pretoria Koliths).
Lomas, Joseph.—‘‘ On some Flint Implements found in the Glacial Deposits
of Cheshire and North Wales’’: Proc. Liverpool Geol. Soe., 1899,
vol. viii, p. 334.
Rudler, F. W.— President’s Address: Journ. Anthrop. Inst., 1899,
vol. xxvili, p. 318.
1900. Stopes, H.— “ Unelassified Worked Flints’?: Journ. Anthrop. Inst., 1900,
vol. xxx. Some Kolithic types figured in pl. xxxv.
Bullen, R. Ashington.—‘‘ The Prestwich Collection of Flint Implements’? :
Science Gossip, 1899-1900, n.s., vol. vi, p. 379.
»” : Trans. S.E. Union Scient.
110 Prof. W. B. Benham—A Giant Fossil Cirripede.
1900. Rutot, A.—‘‘ Exposé sommaire de résultats d’excursions entreprises dans les
ballastidres des environs de Paris’’: Bull. Soc. Belge de Géologie, etc.,
1900, tome xiv, p. 324.
1901. Howorth, Sir H. H.—“The Earliest Traces of Man’: Grot. Mae.,
1901, Dec, ITV, Vol. VAI) ps 337:
Bennett, F. J.—‘‘The Karliest Traces of Man’’: Gzou. Mae., 1901,
Dec VE Nol Wale ps2
Bullen, R. Ashington. e Rolithic Implements’’?: Gzrozt. Mae., 1901,
Dee. IV, Viol. VIII, p. 426.
Bulien, R. Ashington. — Rolithie Implements”’: Journ. Victoria Institute,
1901, vol. xxxiii, p. 191, plates.
Darbishire, PB, D8 On the Implements from the Chalk Plateau in Kent;
their character and importance’’: Manchester Memoirs, 1901, vol. xlvi,
No. 2, plates.
Hull, £. —«Rolithic Implements’’: Journ. Vict. Inst., 1901,vol. xxxiii, p. 414.
Jervis, W. P.—Ibid., p. 2838.
Jones, T. Rupert. —¢Folithic Flint Implements found at Finchampstead
Ridges, Berks’’: Thirty-Second Annual Report of the Wellington
College Natural Science Society, 1901, p. 58, plate.
Rutot, A.— Sur la distribution’ des industries paléolithiques dans les
couches quaternaires de la Belgique’’: Comptes Rendus du Congrés
International d’ Anthropologie, etc. ie Session, Paris, for 1900; Paris,
1901, p. 79.
Willett, ys Cn a Collection of Paleolithic Implements from Savernake ”’
Journ. Anthrop. Inst., 1901, vol. xxxi, p. 312, plates.
1902. British Museum.—‘‘ Guide to the Antiquities of the Stone Age,’’ 1902, p. 10.
Harrison, E. k.—‘‘ Kolithie Flint Implements’’: South-Eastern Naturalist,
1902, p. 16, plate.
Jervis, W. P.— Kolithic Implements are Natural Forms’’: Journ. Vict.
Inst., 1902, vol. xxxiv, p. 283 (letter to the Secretary).
Reid, C. "The Geology of the Country round Ringwood ’’: Mem. Geol.
Surv., 1902, p. 33.
Rutot, A.—<‘* Défense des Kolithes ; les actions naturelles possibles sont
inaptes a produire des effets semblables a la retouche intentionelle ”’
Bulletin et Mémoires de la Société d’anthropologie de Bruxelles, 1902,
tome xx.
Rutot, A.—< Btude Géologique et anthropologique du Gisement de Cergy’
Bull. et Mémoires de la Société d’ anthropologie de Bruxelles, ene
tome xx.
Rutot, A.—‘‘Sur les relations existant entre les cailloutis quaternaires ”’ :
Bulletin de la Société Belge de Géologie, de Paléontologie, etc., 1902,
tome xvi, p. 16.
Warren, S. H.—‘‘ The Value of Mineral Condition in determining the relative
Age of Stone Implements ’’: Grou. Mac., 1902, Dec. IV, Vol. IX, p. 97.
Builen, R. Ashington.—* Kolithic Implements: their use and meaning”’ :
Proceedings Holmesdale Nat. Hist. Club, p. 18.
1903. Bennett, F. J.—‘‘ Kolithic Implements at Belfast and at Bloomsbury” :
Grou. Mac., March, 1903, Dec. IV, Vol. X, p. 127.
TV.—On some Remains oF a Gicantic Fossin CrrRIPEDE FROM THE
TertTiaRy Rocks or New ZEALAND.
By W. Buaxtanp Benuam, D.Sc. (Lond.), M.A. (Oxon), F.Z.S.,
Protessor of Biology in the University of Otago, N.Z.
(PLATES IX AND X.)
N the course of conversation with Professor J. Park, the Director
of our School of Mines, I first heard of the occurrence of
a gigantic pedunculated Cirripede in certain Tertiary deposits on
the east coast of the North Island of this colony. I then wrote to
Prof. W. B. Benham—A. Giant Fossil Cirripede. 111
Mr. T. F. Cheeseman, the Curator of the Auckland Museum, in
which some remains were exhibited: in answer to my request,
Mr. Cheeseman very generously loaned me these remains, and
the following notes are founded on them. I will here express my
thanks to this gentleman for the readiness with which he has, in
this and other instances, complied with my request for the loan
of specimens out of his museum. But these few fragments do not
represent all that is known of the animal; for I understand that
abundant material, collected by Professor Park during his geological
survey, is entombed in boxes in the Colonial Museum at Wellington,
and Professor Thomas, of Auckland, also possesses, as he informs
me, a fair supply of valves, collected by himself.
I have, however, not been able to examine either of these col-
lections. And although the present contribution is very incomplete,
yet I hope that it will stimulate the possessors of better material
to supplement or correct my remarks; at any rate, it will serve
to direct the attention of European geologists and zoologists to the
existence in late geologic times of a Cirripede remarkable chiefly for
its gigantic size, far surpassing any member of the group hitherto
known to science.
Portions of this fossil were exhibited in 1887 by Sir James
Hector at a meeting of the Wellington Philosophical Institute, when
he made the following remarks :—"
“The large fossil Cirripede collected by James Park will probably
be found to belong to the genus Scalpellum, and is distinguished
provisionally under the name Sc. Aucklandicum. In size this fossil
Cirripede exceeds greatly any previously known; in S. magnum
the capitulum being 14 inches in length, while in the Auckland
specimen it is at least 8 inches.
“The fossil occurs in a breccia marking an old shore-line of the
upper part of the Waitemata series, similar to the Cape Rodney beds.
The associated fossils are corals, brachiopods, and echinoderms.
Among the latter are two specimens of Cidaris having plates of
enormous size.”
These fossils were collected on the island of Motutapu, in Auckland
harbour. Park? states that ‘the island consists of Tertiary sandstone
and clays on a highly denuded surface of slates, sandstones, and
schists, of probably Paleozoic age.”
According to Sir James Hector, the Waitemata series belong to
his ‘ Cretaceo-Tertiary ’ system, whereas Captain Hutton regards it
as Miocene.®
Sir James Hector, as above stated, attributed the fossil to the
genus Scalpellum, and proposed the name Se. Aucklandicum, without,
however, further describing it.
But, I think, a careful comparison of the scutum and carina with
the fossil valves described by Darwin indicates a closer resemblance
to certain species of Pollicipes; nevertheless, I do not think I am
1 Trans. N.Z. Institute, vol. xx, p. 440.
2 Geological Reports (N.Z. Government), 1887, p. 22¢
° Hutton: Trans. N.Z. Institute, vol. xxxii, p. 171.
112 Prof. W. B. Benham—A Giant Fossil Cirripede.
justified in transferring it to this genus till a greater number of
valves have been studied, especially in consideration of the difficulties,
pointed out by Darwin, of distinguishing the two genera from the
valves only ; and it must be borne in mind that the criteria put
forward by him are not applicable to the living forms, for he
expressly limited them to fossil representatives.
The only character referred to by Sir J. Hector is the great size
of the fossil ; and certainly this is, as it happens, a sufficient diagnosis
of the species. The largest capitulum known amongst living species
of Scalpellum is that of Sc. Darwiniit, Hoek, which attains a length of
46 mm. (nearly 2 inches) ; and only a few other species approach this
size, viz., Sc. eximium, Hoek, 43 mm.; Sc. gigas, Hoek, 40 mm. ;
and an undescribed species in my possession from the coast of this
island is of the same length as the last. Amongst fossil forms,
the largest capitulum recorded by Darwin is 14 inches (about 37 mm.)
in length, and only two entire capitula reached this size, viz.,
Sc. magnum and Sc. maximum.
Turning to Pollicipes, all the known species are of small size;
existing forms are less than 1 inch (ae mm.), and the only entire
capitulum described by Darwin was 3 inch (say 13 mm.) in length.
It will be seen, then, that the capitulum of the species of which
certain valves are described in the present article was of extra-
ordinary size; it must have attained the enormous length of nearly
a foot (800mm.), and possibly more; for the tergum would, by
analogy with other elongated species, project considerably beyond
the scutum, while the inferior valves would still further add to the
length.
The material at my disposal includes four recognizably identifiable
valves, with some fragments insufficiently complete to describe,
though one amongst the latter is, I believe, a portion of one of the
lower series of the capitulum, probably the ‘ carinal latus.’
The four recognizable valves are—
(a) The carina.
(6) The scutum of the left side.
(c) The rostrum (?).
(d) One of the lower whorl (? the ‘ upper latus ’).
But there is no evidence to show that these plates belong to one
and the same individual.
(a) The Carina. (PI. X, Figs. 3-7.)
This valve is represented by one almost complete specimen and
another less complete, and some broken fragments.
The more complete valve consists of a median, transversely ridged
roof-plate, a ‘tectum’ (of Darwin), with a pair of inflexed ‘ parietes’
forming a flange on either side.
The tectum is long, narrow, nearly flat at the basal extremity,
but much arched from side to side distally. It is gently curved
in the longitudinal direction, but there is no evidence to show that
it was angularly bent upon itself. The basal extremity is uninjured ;
the inner surface slopes gradually to meet the outer surface, so that
GEOL. MAG. 1903. IDises JWG Wolly Sh IP IDS, )
A giant Cirripede (Pollicipes ? Aucklandicus) from Tertiary Beds,
Auckland, New Zealand.
Figs. 1-2, left scutum. Natural size.
Prof. W. B. Benham—A. Giant Fossil Cirripede. 113
a rough but definite edge is here formed. The breadth of the
tectum remains nearly uniform over the lower half, but widens very
slightly near the middle; it then diminishes very gradually towards
the distal portion; although the apex is absent, it was probably
about half the breadth of the base. The lines of growth are
practically transverse, and, as frequently is the case, those near the
middle are more widely spaced than at the proximal extremity,
where they are rather oblique.
The parietes are nearly complete, but are partly broken away
near the distal extremity. Seen laterally, each parietes is practically
a triangle, with a very long curved base, attached, of course, to
the margin of the tectum. The lower or proximal side of the
triangle is longer than the distal, and is slightly excavate, i.e. it is
not a straight line. The distal side, as far as can be judged, is
a straight line; what is left of it appears to be uninjured. The
lines of growth on each parietes are very close set; starting from
the basal extremity they at first run nearly straight, but slightly
obliquely, upwards; then, where the flange widens out, they curve
outwards and bend abruptly backwards, terminating along the
distal side of the triangle. There is thus left a small smooth
‘bay, triangular in form, on the proximal side of the apex.
There is no ridge, but the surface suddenly drops along the line
of junction of tectum and parietes; the angle formed by each of
the latter with the former is about 135°.
The upper end of the valve is broken, but if the tectum be
produced to meet the production of the distal side of the triangular
parietes, the point of union will add about 25 mm. to the total length
of the carina.
The inner surface of the valve is, in its upper half, marked by
a series of fine transverse ridges and furrows; at the actual point
of bending there is a narrow and well-defined ridge, while below,
the surface is smooth.
The following measurements were made :—
mm.
Length of fragment... a Bae 306 360 555 133
Probable total length aa eee oot ... about 160
Greatest breadth of tectum... wish cts eh aH 18
Breadth at base... ate be Bae ae be 15
Breadth at fractured end ... ae aoe ans ee 10
Thickness... “a a aa uss aise dad 2
Parietes—greatest breadth ... aes oe ais es 25
(6) The Scutum. (Pl. IX, Figs. 1-2.)
This valve is 74 inches in length, and only 14 in breadth; it is
thus remarkably narrow in proportion to its length. It will be
convenient to distinguish a ‘main plate’ from a ‘flange’ which
exists on one side, and is scarcely seen when the valve is looked
at squarely from above; this ‘flange’ is the greatly inflexed latero-
tergal region of the valve, which is set on to the ‘ plate’ at an angle
of about 115°. The ‘main plate’ is almost complete. There appears
to have been a small apical region broken or worn away; but apart
DECADE IV.—VOL. X.—NO. III. 8
114 Prof. W. B. Benham—A Giant Fossil Cirripede.
from this, and a small rectangular portion broken off the base
which does not affect the shape or measurements, the valve is entire.
The basal margin is straight; the lateral and occludent margins form
right angles with it, and are therefore parallel for the lower third
of their course. The occludent margin, as a whole, is a continuous
convex curve ; while the other margin of the main plate is doubly
curved, so as to form an §-shaped line, which is at first parallel
with the occludent margin, then bends away from it, and finally
curves gently towards it, so that a blunt apex is formed.
The surface of the plate is nearly flat from side to side in its
proximal region, but is distinctly convex as the distal extremity is
approached. Moreover, when viewed from the side, the plate
exhibits a gentle §-shaped bend, the middle of it being concave out-
wards, the upper and lower ends convex.
The lines. of growth are transverse, nearly straight, and are
sufficiently prominent over the greater part to form slight ridges,
but these become evanescent towards either end, and at the same
time the growth-lines become closer together, especially as the basal
margin is approached, where they are very crowded.
The ‘flange’ or tergo-lateral region of the scutum is very much
inflexed, forming, as I have stated, an angle of about 115° with the
main plate ; it is somewhat thinner than the latter, and is triangular
in form; the apex of the triangle, the tergo-lateral angle, i.e. its
widest part, where it is 20 mm. across, is at the same level as the
widest part of the main plate; the proximal side (lateral margin)
passes down and soon becomes nearly parallel to the side of the
plate, whilst its distal side (tergal margin) is shorter and passes to
the apex of the main plate.
The flange differs in appearance from the plate itself, owing to
the direction and character of the lines of growth; these are very
fine and close together, their general course is longitudinal, but
gradually curving outwards to reach the tergal margin, where their
ends constitute a slight ridge; this margin is, I believe, the true
uninjured edge. In thus curving outwards a small smooth bay is
left on the proximal side of the tergo-lateral angle.
I have been unable to examine the inner surface of the valve,
as it is closely attached to the matrix, but the concavity extends
up to the apex.
The following measurements were taken :—
Total length of scutum —.. ae ee AA ms 187
Greatest breadth of main plate a6e 365 380 366 38
Basal breadth ee 58 ane AG wen 30
Thickness at base ... re fet Ste Bis ae. 2°25
Thickness at apex ... 500 6 ye do 1
Greatest breadth of flange .. ne neo 443 Be! 20
(c) The Rostrum (?). (PI. X, Figs. 8-9.)
This valve is undoubtedly one of the median plates of the inferior
series; it may be either the rostrum or sub-carina. It is much
smaller than the preceding valves, is quite symmetrical and hastate
Prof. W. B. Benham—A Giant Fossil Cirripede. 115
in form; the longer axis is median, and the shorter axis much nearer
the broader end. One end of the plate is sharply pointed, while
the opposite angle is much more obtuse.
The valve is arched in the longitudinal direction, and is markedly
convex from side to side; at the broader end a distinct but low
keel occupies the median line.
The surface is marked by closely set lines of growth angulated
in the middle line, the angle being directed towards the broader end.
mm.
Length of rostrum... aah aae ae Ado BEA 45
Greatest breadth ao Bee “os : a8 13
(d) One of the Lateral Valves. PL X, Figs. 10-11.)
One of the valves, which at a first glance somewhat resembles
the apex of a scutum, is doubtless one of the series of lateral plates,
very probably the ‘upper latus.’ Unfortunately it is imperfect,
but so much of it remains that it is possible to get an idea of the
shape, though not, perhaps, of the size, of the perfect valve. Like
the scutum, it consists of a ‘chief plate’ and a ‘flange,’ which,
however, lie nearly in the same plane.
The ‘ chief plate’ is long, narrow, and symmetrical, about a median
line; one end is broken across, the other is a blunt point. The two
lateral margins are symmetrically curved, nearly parallel at the
fractured extremity, but gradually approximate in the opposite
direction, so as to form feebly convex margins. The plate is marked
by nearly transverse growth-lines, which in the proximal moiety
are slightly distorted by a linear depression cutting across them
nearer one margin than the other. This depression traverses about
one-half the length of the plate, at first parallel to the margin, but
later bending away from it towards the middle line.
On one side of the main plate is a thinner, narrow flange, triangular
in general form ; it is in reality merely the slightly inflexed margin
of the valve, and, as in other cases, the lines of growth take a different
direction from those on the main plate, passing obliquely upwards
to cut the distal side of the triangle, which is uninjured, and slightly
thickened.
mm.
Length of fragment . ae is ne ae ee 70
Breadth of main plate ihe abe sod Be ae 22
Greatest breadth over all... a ae ee ae 30
Thickness .... Bre Bo a5H ae ae 1°5
Remarks.
Having given an account of these valves, I will proceed to
consider those characters which may enable us to place the fossil
in its proper genus. The question naturally arises, is the fossil
a member of the genus Scalpellum, or is it Pollicipes ?
In his classic monograph on the fossil Cirripedes, Darwin?
points out the difficulties of deciding the matter when only a few
valves are available; and in his work on the living forms,” he also
1 «* A Monograph on the Fossil Lepadid ’’: Paleeont. Soe., 1851.
* “* A Monograph on the sub-class Cirripedia (Lepadidie) ”?: Ray Soc., 1851.
116 =Prof. W. B. Benham—A Giant Fossil Cirripede.
indicates the difficulty of drawing any hard and fast line between
the two genera. In fact, one of our New Zealand species, Scalpellum
villosum, is the very stumbling-block that he discusses. Nevertheless,
Darwin, from his great experience in identifying these Cirripedes,
indicates certain characters on which he relies, at any rate for fossil
forms, in discriminating between the two genera.
In speaking of the carina, Darwin thus characterizes it for fossil
species of Scalpellum (p. 17): it is ‘‘narrow, widening but little
from the apex downwards, slightly or considerably curved inwards ” ;
and adds further down the same page that ‘the chief character
by which the valve can be recognised as belonging to Scalpellum is
the distinct separation, by an angle often surmounted by a ridge,
of the tectum from the parietes, which are either steeply inclined
or rectangularly inflected ; the lines of growth on the parietes are
oblique.”
On the other hand, in Pollicipes the carina is described (p. 49)
as being “either bowed inwards or is straight; it widens from
apex downwards more rapidly than in Scalpellum; generally a con-
siderable upper portion projects freely, and this portion is always
much less concave than the lower part.” Further on he says, “the
parietes are generally more or less inflected, but they are not
separated by any defined ridge or angle from the tectum. Lines
of growth on the parietes are transverse or only slightly oblique.”
From these two quotations it would appear pretty certain that the
carina described above would be attributable to the genus Scalpellum-.
But in examining the plates illustrating this genus we find in none
of the species a carina that resembles that under discussion.
The present fossil has not only a much narrower tectum, but the
difference in width at the two extremities is very much less than in
any figured. The base, and therefore the lines of growth, are in the
latter angulated, instead of being transverse as in our fossil. Again,
the parietes are in most of the figures scarcely, if at all, visible in
a dorsal view of the valve, since they are much more steeply
inclined to the tectum than in the present instance. Further, the
parietes in Darwin’s species of Scalpellum is either a continuously
curved plate of nearly equal width throughout, or its edge forms
a chord to the arc of a circle described by the tectum.’
In our fossil we do not know with absolute certainty the true
curve nor the true length of the carina, nor the position of the
umbo; nevertheless, the appearance presented by the oblique margin
of the distal moiety of the parietes leaves little doubt but that it is
the natural, uninjured margin. If this be the case, and if we suppose
this edge to be produced to meet a continuation of the tectum, we
shall obtain the true form and size of the whole valve, which is not
greatly curved nor much longer than the portion preserved, while
there is no reason to doubt that the umbo is terminal.
Now it is a distinctly remarkable fact that the only carina figured
by Darwin that does bear resemblance in the points above referred
1 There is one exception, Sc. magnum, in which, however, the umbo is not
terminal as it is in the rest, and as it is, in all probability, in our fossil.
Prof. W. B. Benham—A Giant Fossil Cirripede. 117
to is attributed to the genus Pollicipes, viz. P. reflexus (see pl. iii,
figs. Sa-c). In this species, as in one or two others, the lines of
growth, and therefore the base itself, are transverse and straight; the
parietes are seen from above, and, though not precisely like those of
the present fossil, yet bear a closer resemblance to it, in possessing
a slight angle on its margin, than do those of any of the species of
Scalpellum ; while the inclination of the parietes to the tectum, as
represented in the transverse section, is also similar, as is the
general direction of the lines of growth, though the angulation
of these, which occurs in our fossil, does not appear to exist. It
is, moreover, the only Tertiary Pollicipes described in the monograph,
having been found in the ‘upper marine Hocene’ at Colville Bay,
Isle of Wight.
The scuéwm: in its greatly elongated and much narrowed form
this valve is quite unlike that of any of the fossil species either of
Scalpellum or of Pollicipes figured by Darwin; but among living
species Sc. album, Hoek,’ has a very similar valve, so far as its general
proportions are concerned. But what seems to distinguish our
valve as much as any other feature is the very marked inflexions
of the tergo-lateral region; in most of those figured by Darwin
this ‘flange’ appears to lie very nearly in the same plane as the
‘chief plate’ itself; although in the description of some of the
species, e.g. Sc. arcuatum and P. Angelini, he states that the “ tergo-
lateral portion is inflexed.”
Darwin, in his diagnosis (p. 17) of Scalpellum, says, ‘‘ scuta very
slightly convex, four-sided, tergal and lateral margins being divided
by a slight angle”; whereas Pollicipes (p. 48) possesses scuta which
are ‘“‘ generally three-sided, but sometimes, either from the baso-
lateral or rostral angle being truncated, there is an additional side.
The tergo-lateral margin is either straight or, generally, more or less
convex, but it is never divided into two distinct margins.”
Now, if our scutum be examined merely from the outside, the
tergo-lateral margin is scarcely angulated, and the general outline
(except for its great elongation) resembles the scutum of P. Angelini
or P. acuminatus much more nearly than it does any of the figures
of Scalpellum. If, however, it be viewed from the side there is
a more distinct angle, but even this is not so pronounced as in
Scalpellum, in which the part that I have termed ‘flange’ appears to
be less differentiated than in our species or in the genus Pollicipes.
On the whole our valve seems to agree rather with that of P. Angelina
than with any other fossil Cirripede. In his description of the
scutum of this species Darwin writes (p. 57): ‘The tergo-lateral
portion of the valve, formed by the upturned lines of growth, is
not much developed; the tergo-lateral margin, as seen externally,
is obscurely divided into two lines, of which the upper or tergal
portion has its edge reflexed.”
In reference to the other two valves described, very few words
are necessary. ‘The one which I suggest is ‘rostrum or sub-carina’
is, like our other valves, much narrower than in other species, either
1 Hoek: ‘‘ The Cirripedia (Systematic Part),’’ Challenger Reports, 1883, viii.
118 =©Prof. W. B. Benham—A Giant Fossil Cirripede.
of Scalpelium or of Pollicipes. Of the former, only the rostrum of
one fossil species is known, though, as Darwin pointed out, others
probably possessed it. Amongst living species some have and
others have not a rostrum. In Pollicipes, he says, the rostrum
‘‘resembles the carina, but is shorter and proportionately broader.”
Of the sub-carina we have practically no information.
The form of the latera is very varied in both genera, but only
in a few cases are the lines of growth straight, as in P. glaber
(pl. iii, figs. 10f, &), where it is nearly a right-angled triangle. In any
case, it seems unlikely that these valves will havea diagnostic value.
It occurred to me that some relation in length might exist between
carina and scutum, and that a comparison of this relation in
Scalpellum on the one hand and Pollicipes on the other might aid
me in determining the genus of the fossil.
But an examination of the material contained in Darwin’s
monograph of the fossil forms soon showed the unreliability of
this method of investigation as applied to them, for it is extremely
rare to find a complete capitulum or a set of valves in siti which
can be, without any doubt, attributed to anindividual. Indeed, only
two species of Scalpellum and one of Pollicipes in this condition are
recorded by him.
Further, even in the case of figures of the entire capitulum of
living species it is not always possible to measure with absolute
accuracy the various valves. Nevertheless, from the figures given
below, derived from measurements of Darwin’s and Hoek’s repre-
sentations of the species, a certain proportion—not by any means
a constant proportion, however—may be deduced in regard to the
relative lengths of carina to scutum.
It will be seen that in Scalpellum the carina is always longer,
usually much longer, than the scutum; whereas in the case of
Pollicipes these two plates are much more nearly, or even actually,
of the same size.
[Length of capitulum, 100.]
Scalpelium. Length of carina. Length of scutum.
vulgare ay ih oe Aue 83 eae 58
rostratum oe 500 906 p00 83 000 58
ornatum an 1k ae aa 17 a 55
Peronii se Le See BA ad ey 55
rutilum oe seo ya a0 87°5 a 62°5
Stroemii a as as ak 80 she 50
Japonicum =... 90 50 joe 89 os 64
recurvirostris ... ue iia a 89 ine 53
Darwinii and abe aa ae 78 58°7
regium ... is ee 50 408 90:9 60°6
eximium ane sais sje abe §2°5 75
gigas... ae Abe ode 306 85 575
tritonis ae Es 503 600 93°4 54°8
Pollicipes.
spinosus , ne 4 308 71:2 wo 71-2
cornucopia... ao $50 aes 70 aac 70
polymerus 75 62°5
In attempting to apply this method of comparison to the valves
under discussion, we are in this dilemma, that we do not know—in
Dec: IV, Volw XX, PIS
GEOL. MAG. 1903.
iant Cirripede (Pollicipes? Aucklandicus) from Tertiary Beds,
Ag
Auckland, New Zealand.
Baron Francis Nopesa, Jun.—The Origin of Mosasaurs. 119
fact, we have strong reason to doubt —whether these valves belong
to one and the same individual. But it is, at any rate, noteworthy
that the only scutum and the only approximately entire carina in
this small collection should agree so nearly with the conclusions
derived from a study of Pollicipes, for the scutum measures about
190 mm. and the carina about 160 mm., allowing for the probable
damage at the end.
In other words, we are more likely to find in the entire capitulum
of this fossil that these two valves are nearly equal in length, than
that the carina greatly exceeds the scutum in length, as is the case
in the genus Scalpellum.
So far, then, as this rough calculation goes, it bears out the view
expressed above that the fossil belongs to the genus Pollicipes as
defined by Darwin in dealing with the fossil pedunculate Cirripedes.
For a determination of this point, however, we must await the
researches of those who have a larger supply of material at their
command.
EXPLANATION OF PLATES IX AND X.
Fig. 1.—The left scutum of Pollicipes (?) Aucklandicus, viewed from the outer side,
showing the form of the ‘ chief plate.’
Fie. 2.—The scutum, seen edgewise, to show the outline of the ‘flange,’ or much
inflexed tergo-lateral margin, as well as the general curvature of the plate.
a, basal margin; 4, occludent margin; c, tergo-lateral margin; d, ‘ flange.’
Fies. 3-7.—The carina. Fig. 3, dorsalview. Fig. 4, side view. Fig. 5, the basal
margin, seen end on, to show form of tectum. Fig. 6, the fractured
edge, to show the curvature near the distal region. Fig. 7, transverse
section of another specimen of smaller size, at about the level of the middle
of the valve.
Fic. 8.—The rostrum, external view; a small portion of the apical region is broken
away, but the impression (c’) on the rocky matrix shows the length of the
missing part.
Fie. 9.—The rostrum, side view.
Fie. 10:—The doubtful ‘latus,’ broken across its lower end, external view.
Fie. 11.—The same, viewed from the broken end.
V.—On THE ORIGIN oF THE Mosasaurs.
By Baron Francis Noprcsa, Jun.
ONCERNING the origin of the Mosasaurs three altogether
different views exist: G. Baur regarded the Mosasaurs as
highly specialized aquatic Varanoids; Boulenger is inclined to trace
their origin back to the Neocomian Dolichosaurs; and Osborn, in
a recent paper, doubts that Varanids and Mosasaurs sprang from
a common stem, and regards the latter as “a very ancient offshoot
of the Lacertilia.” Some Lacertilia found in recent years in the
Lower Cretaceous of Dalmatia, and not yet fully compared with
the Mosasaurs, will, I believe, throw fresh light on this subject.
Among the fossil Lacertilia found in Dalmatia two types can be
distinguished, namely, Dolichosaurs and Aigialosaurs, the former
including the genera Dolichosaurus Owen, Pontosaurus Gorjanovic-
Kramberger (= Hydrosaurus lesinensis, Kornh.), Acteosaurus Meyer,
and Adriosaurus Seeley ; the latter, Acgialosaurus G.-Kramberger,
120 Baron Francis Nopesa, Jun.—The Origin of Mosasaurs.
Carsosaurus Kornh., Opetiosaurus Kornh., and perhaps also Meso-
leptos Cornaglia.*
The following chief differences are observable between these
two types :—
' DoLicHosAURs.
Skull relatively small.
Quadrate bone probably slender.
Mandible slender.
Teeth thecodont ?
Vertebre: neck remarkably long, con-
sisting of 13 vertebre.
26 dorsal vertebree.
Ribs: dorsal ribs equally long and rela-
tively short.
No ventral ribs.
Limbs: anterior limbs much reduced in
size.
Hind-limbs twice as long as fore-limbs.
Metatarsal vy not showing Varanid
modification.
AIGIALOSAURS.
Skull relatively large.
Quadrate round as in Mosasaurs.
Mandible strong.
Teeth in sockets.
Neck short, composed of only 7 vertebrae.
21 dorsal vertebra.
The long dorsal ribs vary in length.
Ventral ribs well developed.
Anterior limbs comparatively long.
Only somewhat longer.
Metatarsal v showing distinctly Vara-
nid modification.
According to the description here given the Dolichosaurus, as pointed
out by Osborn, cannot be the ancestor of the Mosasaurs, whereas
the same cannot be said of the Aigialosaurs.
The most remarkable
points of resemblance and difference between the Aigialosaurs and
Mosasaurs are as follows :—
AIGIALOSAURS.
Mosasaurs.
Skull: wpper surface in both cases perfectly the same and strongly resembling the
Varanids.
same bone in the living Varanidee.
Quadrate bone in both types broad and flattened, thus differing from the
Articulation between the front and hind parts of
the mandible present in both types and absent in the Varanide.
Vertebre: 7 cervical vertebre,.no sign
of primitive structure; 21 dorsal
vertebre, like those of the Varanide.
Seven cervical vertebree, showing very
primitive structure (due to pelagic
life?) ; dorsal vertebree varying from
22 (Tylosaurus) to 36 (Chdastes).
Ribs: the sternal ribs are equally developed in both, and their position indicates
in both cases the same kind of sternum, with this difference :—
Sternum broad and large; 6 sternal ribs
touching the sternum.
Shoulder-girdle well developed.
Fore-limbs intermediate between the
Mosasaurid and Varanid type.
Pelvic girdle well developed.
Two sacral vertebra present.
Hind-limbs like front-limbs, both ex-
tremities bearing sharp claws.
Sternum comparatively small; 10 true
sternal ribs present.
Shoulder-girdle somewhat reduced.
Fore-limbs changed to paddles.
Pelvic girdle reduced.
Only one sacral vertebra.
Hind-limbs paddles ; hyperphalangy, and
no claws present.
Dermal covering consisting in both cases of rhomboidal scutes bearing a slight
median elevation.
It is thus evident that the Aigialosaurs show great affinity to the
1 This classification does not correspond with the one given by Gorjanovic-
Kramberger.
Baron Francis Nopesa, Jun.—The Origin of Mosasaurs. 121
Mosasaurs, differing from the latter only in not being as thoroughly
adapted for pelagic life. On the other hand, the Aigialosaurs show,
as remarked by Kornhuber, a strong resemblance to the living Varanids,
differing from these only in those points by which they approach the
Mosasaurs.' ai
The question arises now, do the Aigialosaurs represent the most
primitive Mosasaurs or a family in the suborder of the Lacertilia ?
Taking the Mosasaurs, on account’ of the development of their
paddles, as a distinct suborder of the Squamata, the Aigialosauride
would prove to be a distinct family among the Lacertilia, approaching
greatly the Jurassic type from which the Cretaceous Mosasaurs and
the recent Varanide are the offspring. This type, being terrestrial,
would of course bear greater resemblance to the modern Varanids
than to the pelagic Mosasaurs.
A paper dealing more fully with this highly interesting subject is
to appear in the Geolog. und Palaeontolog. Beitrage in Vienna.
PAPERS REFERRED TO.
Baur.—‘ The Skull of Mosasaurs”: Journal of Morphology, 1892.
Boulenger. — “‘ Osteology of Heloderma”: Proc. Zool. Soc.
London, 1891.
‘Newly described Jurassic and Cretaceous Lizards”: Ann. &
Mag. Nat. Hist., London, 1898.
Gorjanovic - Kramberger. — “ Aigialosaurus”’ : Societas historico
naturalis Croatica, Zagrab (Agram), 1892.
“Hinige Bemerkungen zu Opetiosaurus”’: Verhandl. k.k. geolog.
Reichsanstalt, Wien, 1901.
Kornhuber. —“‘ Uber einen neuen fossilen Saurier”: Abhandl. k.k.
geolog. Reichsanstalt, Wien, 1873.
“ Carsosaurus Marchesettii”’: loc. cit., 1895.
“ Opetiosaurus Bucchichi”’: loc. cit., 1901.
Lortet.—“‘ Reptiles fossiles du bassin du Rhéne”: Archiv Musée
hist. nat. Lyon, 1892.
Herriam.—‘‘ Pythonomorphen” : Paleontographica, 1894, vol. xli.
Meyer.—“ Acteosaurus Tomasinii” : Palesontographieca, vol. vii.
Osborn.—‘ A complete Mosasaur Skeleton”: Mem. Amer. Mus.
Nat. Hist., 1900.
Owen-—“ Fossil Reptiles, Cretaceous Formation”: Paleeontographical
Society, 1851-1864.
Seeley.—“ Adriosaurus Suessi” : Quart. Journ. Geol. Soc., 1881.
Willistou.—‘* Mosasaurs’’: University Geol. Surv. Kansas, 1898.
1 It cannot be certainly known whether the pterygoids of the Aigialosaurs bore
teeth, but I am inclined to believe they did, since in Opetiosawrus the crown of a tooth
lying near the hyoid bone (=columella of Kornhuber) seems to differ in size both
from the mandibular and (presumably also) maxillary teeth of this animal.
122 G. W. Bulman—The Geological Chronometer.
VI.—Tue GeroLocicaAL CHRONOMETER.
By G. W. Burman, Esq.
HE pleasant relations normally existing among geologists,
biologists, and physicists have of late become a trifle strained
on the question of the age of the earth. Biologists, having failed to
induce either geologists or physicists to draw sufficiently large
cheques on the bank of time, have taken to signing the same them-
selves, adding the ciphers ad lib. Professor Poulton has ably
championed the rights of the biologists to do so,’ and in the course of
his argument he contends that there is evidence in the sedimentary
strata to show that their rate of formation was not greater than that
at which deposits are now being accumulated.
So far as I am aware, Professor Poulton’s contention has not been
either controverted or supported by any geologist. Hence it seems
to be a suitable subject for discussion in the GxoLoGicaL MaGazinu.
In the first place, then, what would be the nature of the evidence
we might a priori expect to find to show that one set of beds was
accumulated in a shorter time than another of equal thickness ?
Would there, in fact, be any difference such as would enable us
positively to decide the question ?
Secondly, we may examine and compare rocks which we know,
or have reason to suppose, have been formed at different rates.
Now, according to Sir A. Geikie, if the rocks of the stratified systems
were laid down at the greatest rate suggested by the facts of
denudation, 73,000,000 years would be required; if at the least,
680,000,000. In other words, the greatest rate of formation is more
than nine times the least. We ought, then, to be able to put the
question to the test of actual observation. Do the deposits formed
at the greater rate differ in any essential characters from those
formed at the lesser? If we can establish any difference by
observing recent deposits, then we can apply the criterion to the
strata of past ages. But, so far as I am aware, no geologist has
pointed out any specific characters by which a quickly formed
deposit can be certainly distinguished from a slowly formed one.
This may be, of course, that they have not specially looked for
such characters. It seems more probable, however, that there are
no reliable criteria.
“The geological agency to which attention is chiefly directed by
those who desire to hurry up the phenomena of rock formation,”
Professor Poulton tells us, “is that of tides.” And to prove that
tides were not sufficiently high in time past to do so, two things are
relied on.
First, that the rocks indicate deposition under tranquil conditions,
and secondly, that ‘“‘extremely delicate organisms” are found in them.
“There are, then, among the older Paleozoic rocks a set of deposits
than which we can imagine none better calculated to test the force
1 Presidential Address to the Biological Section (D), Brit. Assoc., Liverpool, 1896.
G. W. Bulman—The Geological Chronometer. 123
of the tides; and we find that they supply evidence for exceptional
tranquility of conditions over a long period of time.”
But, we ask, would the existence of higher tides necessarily
destroy this appearance of tranquility? There is, so far as I am
able to grasp the facts of the case, no grounds for supposing that
higher tides would prevent tranquility of deposition. But we can
put the matter to the proof. We have deposits which have been
laid down in lakes and inland seas where there are no tides. Do
these show the marks of tranquil deposition—whatever these are—
to a greater degree than those of the open ocean? Would any
geologist be able to distinguish the deposits of the Mediterranean
as having been laid down under more tranquil conditions than
those of the Atlantic ?
As regards the extremely delicate organisms which, Professor
Poulton remarks, are found in the Silurian, it is difficult to realize
how a higher tide would affect them. And it is not quite clear
whether it is the fact of these delicate organisms having lived or
their having been preserved which is supposed to show that the tides
were not appreciably higher in Silurian times. Professor Poulton’s
exact words are :—
“The remains of extremely delicate organisms are found in immense
numbers, and over a very large area. The recent discovery, in the
Silurian system of America, of trilobites, with their long delicate
antenne perfectly preserved, proves that in one locality (Rome,
New York State) the tranquility of deposition was quite as profound
as in any locality yet discovered on this side of the Atlantic.”
If the higher the tide the less delicate the organism capable of
living in the water, then the organisms of the Mediterranean ought
to be more delicate than those of the Atlantic. Here, then, we can
appeal to facts. As the question is outside the scope of my knowledge
I must leave it in the form of a query. But, so far as my geological
knowledge carries me, the fossils of lake and inland sea deposits are
not of more delicate organization than those found in the strata of
the open ocean.
And if the finding of a few of the “long delicate antenne”’ of
trilobites in America proves the profoundness of the tranquility,
what does their universal absence in this country show? Again,
there arises the question of the relative delicacy of the organisms
of the Silurian. Have we the right to say they are as delicate as
some of the organisms of our present seas? Can we, for example,
really say from what we know of their remains that the graptolites
were not able to stand more tossing about—assuming for a moment
that higher tides would make it more tempestuous —than the
Sertularia of our present seas? The chitinous rod of the graptolite
may have been very tough and strong. We have no means of
measuring its strength. It must be left an open question whether
or not it was fitted to live in a more stormy ocean than the present.
Again, Professor Poulton says :—“ Thus the attachments of marine
organisms, which are permanently rooted to the bottom or on the
shore, did not differ in strength from those which we now find, an
124 G. W. Bulman—The Geological Chronometer.
indication that the strains due to the movements of the sea did not
greatly differ in the past.”
But have we any grounds for speaking positively on this point ?
Take, for example, the ligaments by which the Brachiopoda are
attached to the sea bottom. We can measure the strength of the
cable of an existing terebratula, but we have no means of testing the
strength of the strand which anchored Terebratula hastata to the bed
of the Carboniferous ocean. ‘The actual cable is no longer there; it
is a mere impression, a cast, or chemically altered. And certainly
the anchored Mollusca—the Brachiopoda—were more numerous in
the early geological ages than other classes, while they are com-
paratively rare at the present day.
Again, Professor Poulton brings forward evidence of a similar
kind to show that movements of the air were not greater in the
geological past. ‘‘ We have evidence of a somewhat similar kind to
prove uniformity in the movements of the air. The expanse of the
wings of flying organisms certainly does not differ in a direction
which indicates any greater violence in the atmospheric conditions.”
Quoting the case of the island of Madeira, where an unusually large
proportion of the beetles are wingless, and those which fly possess
the powers of flight in a higher degree than those on continental
areas, he leads us to the conclusion that if there had been greater
air currents there would have been a like state of things in the
geological past, with regard to winged creatures in general.
The evidence is rather slender for the conclusion which is built
on it. For, as regards fossil organisms, it is the mere relative
expanse of wing we have to go by. But suppose it was set us as
a mechanical problem, “Given a flying organism, to fit it for more
stormy conditions,” how would we endeavour to solve it? Increase
the size of its wings? That might only the better enable the wind
to blow it away. Diminish them? ‘That would curtail its powers
of independent flight. The only solution would appear to be to
increase the strength of the muscles, diminish the weight so far as
consistent with strength, or alter the shape of the wings. All these
things may have occurred in the ancient fliers.
Again, Professor Poulton quotes Professor G. Darwin to the effect
that the size and strength of the trunks of fossil trees afford “ evidence
of uniformity in the strains due to the conditions of the atmosphere.”
But I maintain that, although we can measure the size of a fossil, we
cannot from it accurately gauge the strength of the living organism.
The original substance is no longer there, or there only in part.
And we know from our existing vegetation how vast a difference
there may be in the general form of the trees which are able to stand
the present atmospheric strain. But-this question of possibly greater
atmospheric strain in the past does not seem to be of great importance,
as no geologist who has protested against over strict uniformitarianism
has laid much stress on it.
And besides tides and winds, there are other geological agents
which may conceivably have been more active in the past.
(1) Rainfall. There certainly must have been a time when
G. W. Bulman—The Geological Chronometer. 125
evaporation —owing to greater heat of the earth, and con-
sequently rainfall—was greater. Only if this state of things is shifted
back beyond the period of the formation of our earliest stratified
systems, can we escape the conclusion of greater geological activity
in the past. And the greater the rainfall the greater the denudation,
and consequent rock-making. This quicker formation, again, would
probably not be shown in the rocks themselves.
(2) There may have been a larger amount of C O, in the atmo-
sphere. In the original atmosphere of the globe there was probably
a very large quantity of this gas. ‘There may have remained in the
atmosphere of the early geological ages an amount far. in excess of
the present supply.
(3) There may have been greater exuberance of life when the
waters of the ocean were warmer, as they once must have been on
the hypothesis of a cooling globe.
Greater rainfall, more C O, in the atmosphere, and a warmer ocean,
all must once have been: they may have been late enough in time to
affect the rate of deposition of the known stratified rocks. The
question, then, really is, are we justified in putting them so far back
as to make them anterior to the beginning of geological history ?
Those who are demanding more and more time must remember that
the longer the period granted for the laying down of the stratified
systems, the nearer we get to the epoch when the activity of
geological agents must have been considerably greater than it is
to-day. And if they assume that all the known stratified rocks were
formed at the present slow rate of deposition, they leave unaccounted
for the great series of strata which must have been laid down when
geological activity was greater. They must appeal not merely to
the imperfection of the record, but to its total absence so far as
concerns the period before the present slow rate of deposition began.
Professor Poulton is at great pains thus to cut away the ground
under the feet of the geologist who would “hurry up the process of
rock formation.” But even granting all that is claimed to have been
proved, the biologist only gets in this way some 400,000,000 years.
And this is so obviously too little that it seems hardly ‘worth while to
have troubled the geologist at all. Speaking of that curious organism
Peripatus, which has been variously classed in the zoological scheme,
Professor Poulton says:—‘ Peripatus is not known as a_ fossil.
Peripatus has come down, with but little change, from a time, on
a moderate estimate, at least twice as remote as the earliest known
Cambrian fossil.”
Now, if we put back the origin of Peripatus to a time as far
anterior to the Cambrian as the Cambrian is to the present day, how
far must we put back the origin of the simplest form of life? Well,
Peripatus is a somewhat advanced organism—about the level of the
insects—and on the assumption, approved by Professor Poulton, that
evolution is slower among the simpler organisms we should perhaps
place the first appearance of life on the globe as much _ before
Peripatus as the origin of Peripatus is before the present. This
places the commencement of life at a point four times as remote from
126 G. W. Bulman—The Geological Chronometer.
the present as the Cambrian. If, then, we take the period from
Cambrian to present as 400,000,000, we get 1,600,000,000 years as
the time during which there has been life on the globe. And there
must have been a time anterior to this before life on a heated globe
was possible. Yet Professor G. Darwin only allows 500,000,000
as the life of the sun!
Again, since we must suppose that rock formation began before
life, what has become of the great series of pre-Archzean deposits
which must have been laid down? Supposing for a moment that
the Archean rocks represent a period as long as from the Cambrian
to the present, we have an interval as long as from the lowest
Archean to the present in which strata were being formed. Of this
great series, which must have been, we know nothing. It is hardly
conceivable that they should have entirely disappeared, leaving no
trace behind. Time, we know, not only devoured his children, but
also the stone offered in lieu of one of them. Yet we should hardly
have supposed him capable of devouring quite so much rock.
Of course, no one can object to Professor Poulton, and those of like
views, asserting that, on their hypothesis of the origin of the organic
world, this or that organism must have existed so many million years
ago, or at such and such a geological epoch. But if they are able,
from the study of an existing form, to say positively that it must have
existed at such a time, in spite of its entire absence in the known
geological record—and even in spite of the absence of any geological
record at all—it seems superfluous to appeal to geology at all.
Biologists had better at once declare their entire independence.
Professor Poulton practically does so. For after disposing of
geology in the manner indicated he says: ‘“ We are therefore free
to follow the biological evidence fearlessly.”
One can only admire, while one wonders at, Professor Poulton’s
boldness. Geologists are yet sorely perplexed with the problem of
the Archean rocks. They have not yet definitely decided whether
they are metamorphosed ordinary sediments, part of the original
solidified crust of the earth, or chemical precipitates from a hot
primitive ocean. Professor Poulton assumes, not merely that
ordinary sedimentation, but life also was possible on the globe
untold ages ere the earliest known pre-Cambrian rocks were
laid down.
Darwin found Lord Kelvin with his 100,000,000 years an “ odious
spectre”; Professor Poulton apparently agrees with Butler that
“There needs no other charm or conjurer
To raise infernal spirits up but fear,”
and boldly waves back both geologist and physicist. He apparently
adopts as his motto the advice of the Sybil to Hneas—
“Tu ne cede malis; sed contra audentior ito
(Jua tua te fortuna sinet,”’
F. J. Bennett—Eolithic Implements at Belfast. 127
which may be freely translated, “If facts go against you, assume the
more boldly.”
And so, having freed himself from both geological and physical
evils, in the form of narrow balances at the bank of time, he holds
himself free to go boldly where biological speculations permit. It is
magnificent, but it is not science.
ViIl.—EHottruic ImptemMents at Betrast AND at BLoomspury.
By F. J. Bennett, F.G.S.
N R. J. W. KNOWLES, M.RB.I.A., of Ballymena, read a paper!
on what appeared to him to be flints chipped similarly to
the eoliths, which he had found in the Interglacial gravels of Ireland.
This gave rise to a discussion, in which five speakers in succession
gave reasons, or rather expressed opinions, adverse to their artificial
character; and as these seemed based on some misconceptions, and
also as I was the only one who spoke for them, and was told I must
be brief, and so could not fully reply to them, I do so in the present
form, and I state, as far as I remember, what took place in as few
words as possible.
Mr. Knowles himself took a neutral position, but suggested that,
if they were implements at all, they might have been used as
scrapers for scraping hematite.
The objections were: that these so-called eoliths were found in
such extraordinary numbers that they might be the result of
natural causes, and that their upholders must disprove this; that
the flints in question were those of the Clay-with-Flints, a deposit
due to the chemical dissolution of the Chalk-with-Flints; that, if
admitted to be artificial, they could not be older than the Paleolithic
implements of the high levels, as they were both found in the same
deposits; that similar flints were to be found in the Boulder-clay,
and, as man was post-Glacial, that was a positive refutation.
Professor Boyd Dawkins, LL.D., F.R.S., took a prominent part
in the discussion, and it was from him indeed that most of the
objections came.
Replying to the objections, I would say that, as to their extra-
ordinary numbers, “in countless thousands” as had been stated,?
that might be expected from their very rudeness. If these are the
very earliest tools of the earliest men we should, on evolutional
grounds, expect them to range from natural forms (selected in their
1 Paper read before British Association, Belfast, Sept. 1902.
2 The new pit sunk by Mr. Harrison and myself last year at Parsonage Farm, Ash,
confirms most fully those sunk in 1894. I took a careful note of the percentage
of worked as compared with the unworked stones, and this varied from 4 to 9 per
cent. ; out of the many ‘cart-loads’ of stones got out the worked stones would not
make even one barrow-load, and as a matter of fact this pit, sunk 12’ 8’x45’, only
yielded some 200 specimens. I understand that to the Koliths exhibited at Blooms-
bury a label is attached with these words, ‘‘ Supposed to be the work of man.”? Now
this might lead many to assume that the Paleeoliths were undoubtedly the work of
man, and yet there is no veal proof of this, and the same words might apply to both
Kolithic and Paleolithic implements (so-called).
128 F.. J. Bennett—Eolithic Implements at Belfast.
first stages as adaptable to man’s primitive needs, when first conscious
that some tool as an adjunct to the hand would be a useful supple-
ment to that member) to modifications by rude chipping of that
natural form into more and more artificial forms; and these
gradations are of course very difficult to follow. ‘This renders it
necessary that no opinion should be formed unless a large series of
these so-called implements has been examined, such as Dr. Blackmore’s
at Salisbury (which converted two of my late colleagues) and
Mr. Harrison’s at Ightham. The latter, none of the objectors had
seen, though by some misunderstanding the Section thought they
had. As to their being all due to natural causes, such as ice-
pressure, wave and river action, this objection has been very
fully met by the late Sir Joseph Prestwich in his letter “‘ Nature
and Art,” in the GroLogicaL Magazine, Dec. IV, Vol. II, No. 374,
p. 375, August, 1895. There he repeats a former challenge for any-
one to produce half a dozen shore-flints of any of the plateau types
figured in the five plates that he published in his “‘ Collected Papers,”
and no one has yet produced these.
Still, I might add, undoubted paleoliths have been found in beds
where all these causes have had full play ; not so certain, indeed, in the
case of ice-action, though implements with parallel strize similar to
ice-markings are not uncommon; and where waves, as in the case
of the Paleolithic implements found at the base of sea-cliffs, have
bruised and battered them, man’s -work stands out still, and the
same remark applies to implements found in the river-gravels.
Besides this, no one has yet made a collection similar to
Mr. Harrison’s, of ice-, wave-, or river-formed specimens. As to the
statement that they are similar to the flints (and this is what
Professor Boyd Dawkins meant, I suppose) of the Clay-with-Flints,
none have been found in this deposit; they are found in a distinct
gravel-bed, at an altitude of 755 feet O.D. Then, as to the statement
that Paleolithic implements are found in the same deposits as the
high-level Holithic implements, it is true that in one or two instances
a Paleeolithic implement was dug up, but how or when is not known.
On the contrary, the evidence of the two pits sunk by Mr. Harrison
in 1894, with the grant made by the British Association, shows that
the gravel-bed at 74 feet yielded a considerable number of Holithic
implements only, and the five additional pits sunk by Mr. Harrison
to satisfy himself confirmed this. The objection that, as man is
post-Glacial, therefore he cannot be pre-Glacial, is a mere dogmatic
assertion. Again, the stony loam, the first bed met with in the
above pits, cannot surely be Clay-with-Flints, as it rests on a gravel-
bed, which lies on 27 feet of Tertiary beds, and not on Chalk, as
Clay-with-Flints should.
Thus, I think that all the objections have been fairly considered
and met.
But in spite of the opposition to the acceptance of the eoliths,
Mr. Harrison and his supporters must be gratified to find them
occupying so important a place in the recent Geological Survey
Memoir on Sheet 314 of ‘“‘The Geology of the Country around
Reviews—Recent Excavations at Stonehenge. 129
Ringwood”; also in the British Museum, Bloomsbury, and
Mr. C. H. Read’s “‘ Descriptive Guide to the Stone Age.” In this
Guide (an otherwise carefully written work) no provisional place
has been given to the eoliths before the paleoliths in the
classification, and the mention of these appears in the middle of the
Palzolithic period; this must lead to confusion. Mr. Read seems
impressed by the eoliths, and treats them most fairly, though it is
very unfortunate that, while all the other illustrations are well done,
the eoliths at p. 37 show in their drawing only feeble evidence
of ‘work.’ Mr. Read, at p. 33, refers to the important collection
of Holithic implements from Sir Joseph Prestwich’s collection in
the Natural History Branch of the British Museum at South
Kensington. This should be carefully studied as additional
illustrations of the Stone Age.
a53 2st W108 2h WA Se
J.—Recent Excavations at STonEHENGE, communicated to the
Society of Antiquaries by Wittram Gowtann, Esq., F.S.A.,
F.L.S., etc. With a Note on the Nature and Origin of the
Rock-fragments found in the Excavations, by Professor J. W.
Jupp, C.B., LL.D., F.R.S., F.G.8. 4to; 93 pages, with 4 plates
and 29 text-figures. Printed by J. B. Nicols & Sons, Victoria
Street, Westminster, 1902.
HE Antiquary and the Geologist have individually for many
years past published their observations on Stonehenge, and
their notions about its origin and structure; but now, in actual
co-operation, they have united to give a real description and sound
Opinion of this venerable monolithic monument of ancient labour
and intelligence. With the consent and generous help of the Owner,
the valuable assistance of willing experts, and the utilization of any
useful information from among the already published notes, a great
mass of authentic particulars has been thus collected and arranged
to a good purpose.
The descriptive text (forming part of the Society of Antiquaries’
Archeologia for 1902) is admirably printed, with numerous illus-
trations, several of which are produced from excellent photographs
taken during the operations and kindly lent by a lady of the
neighbourhood. Every stage of the excavations made around the
foot of the prominent and well-known ‘leaning stone,’ which had
to be restored to its original vertical position, as it was when a part
of the chief Trilithon, has been described and figured in detail.
Thus one of the chief objects of this important engineering under-
taking has been carefully worked out. Another object to be
attained was the realization of some detinite history of the great
standing stones of Stonehenge, as far as the relative number, position,
and characters of the blocks and chips of the various kinds of stone
got from the diggings can prove anything as to the cause, method,
and time of their imbedment in the subsoil.
DECADE IV.—VOL. X.—NO. III. 9
130 Reviews—Recent Excavations at Stonehenge.
The large monoliths of the outer circle and the trilithons of the
‘Horse-shoe’ are of the well-known Sarsen Stone, namely, relics
of concretionary masses of Tertiary Sandstone (probably of the
Bagshot Sands, which once lay over the Chalk). They range in
their structure from granular (saccharoid) to compact and quartzitic
denseness. Sarsens having the latter character were found only in
the diggings, as blocks and hammer-stones, used in shaping and
dressing the monoliths, or as fragments of such hammers.
The small monoliths, commonly called ‘the Blue Stones,’ and
forming the inner circle and the inner horse-shoe, consist of aqueous,
schistose or metamorphic, and sedimentary rocks. At pp. 73-78
(1) the Sarsen Stones and their constitution are fully treated
of by Professor Judd. (2) Ophitic diabase (p. 74) has been recog-
nized, with varieties, in fragments and in a still standing stone.
(3) The schistose and fissile rocks are highly altered basic tufts
and agglomerates (p. 74) ; their fragments are numerous, but only
the stump of one of this sort of stone has escaped the action of
weathering and other destructive agencies. (4) Fragments of
altered rhyolites and diorites (p. 75), formerly often referred to
as hornstones, etc., present various characters not readily determined,
and indicate the former existence of a stone of this material. (5)
Sandstone, grit, and conglomerate, including the micaceous sand-
stone of the ‘altar-stone,’ and probably equivalent to the Coronation
Stone in Westminster Abbey, from the Old Red Sandstone of
Perthshire, occur among the fragments. (6) Greywackés (p. 76),
that is, granular quartz and altered felspar, with argillaceous matter,
among the fragments, show that stones of such material were
present, but probably were easily weathered away. (7) Argillaceous
flagstones and slate (p. 76) must have been among the standing
stones, but were completely weathered away, especially when their
bed-planes and cleavages were set vertically. (8) Glauconitic
sandstone (p. 76), probably of the Upper Greensand, occurred in
a few fragments. (9) Flint, from the neighbouring Chalk (p. 77),
was present as very numerous rough chisels and hammers, and the
chips and fragments of such tools. Some small hammers of crystal-
line rocks and quartzite (hard sarsen-stone) were also found, and
several large masses, the weight of which (upwards of 50 and 60
pounds) and the probable method of using them are given (p. 34).
The stone implements found at Stonehenge are carefully figured
(23 of flint, 7 hard sarsen, and 1 argillaceous sandstone) at pp. 22-25 ;
they are mostly blunted and battered by use. Flint tools corre-
sponding in shape from Grimes Graves and Cissbury are figured at
pp. 27-28.
Important observations are made (at pp. 37, etc.) on the modes
of erection and the probable age of Stonehenge. The finished
surfaces of all the Sarsens, where preserved, had been tooled with
hard hammers, and the markings cannot be produced by present
mason’s tools (p. 43). The methods by which the great monoliths
were set up.and secured in the ground were shown in detail during
the excavations as far as gone (pp. 44-48). The legend of the
Reviews—Egyptian Geology. 131
‘Blue Stones’ having been brought from a distance and set up as
a sacred circle, and the supposition that the Sarsens were added
afterwards around them, are disproved by evidence of their con-
temporaneity, by the mode of occurrence of the chippings, and of the
stones themselves.
The use of bronze was unknown before 1800 B.c., and there were
no bronze tools found in the diggings. Mr. Gowland is therefore
inclined to consider that Stonehenge was raised before the incoming
of the Bronze Age at the above date. This nearly approximates with
the result of the important astronomical investigation by Sir Norman
Lockyer and Mr. Penrose as to the relative position of sunrise at
the summer solstice and the probable age of Stonehenge.
Professor Judd, in his clear and comprehensive description of the
stones of Stonehenge (pp. 70 et seq.), gives the bold but well-
founded suggestion that all the stones once lay about on the surface
of the district. The Sarsens, being the concretionary relics of the
denuded Bagshot Sands, were large and abundant. The ‘Blue
Stones,’ of smaller size and of various characters, were relics of the
glacial Boulder-clay, which reached in the Southern Counties
further than is usually described. The presence of similar rocks
in the gravels of the rivers of the South of England, including those
that drain Salisbury Plain, support this opinion. The absence of
such rocks, foreign to the district, on the surface now, may be well
accounted for. The softer rocks were gradually weathered away,
and the harder kinds were continually being used for local purposes,
like the existing scattered Sarsens in Berks and Wilts. These ‘ Blue
Stones’ were, moreover, evidently dressed on the spot when taken
to the circle, for their chippings are more numerous than those of
the Sarsens in some of the diggings. T. R. J.
IJ.—Ecyrrian GroLoey.
Survey Department, Public Works Ministry, Egypt. Geological
Survey Report, 1900. Part II: The Cretaceous Region of Abu
Roash, near the Pyramids of Giza. By Hueu J. L. Beapnett,
F.G.8. 8vo; 48 pp., 13 pls. (Cairo, 1902.)
HIS is an attempt to give an adequate description of the geolog
of a small area lying to the west of Cairo. It is a district that
has received the attention of many observers before, as Mr. Beadnell
is careful to record in his historical sketch which forms an intro-
duction. The report is accompanied by a geological map, which the
author tells us is sufficient for present requirements. It is not
possible for anyone who has not been over the ground to criticize
the details of the stratigraphy, but it appears to have been carefully
done, and numerous detailed sections are given which should render
the work of great value to future observers. ‘The author, too, has
a topographical knowledge which is so exact as to allow him to
write in a more interesting manner than is usual in official reports.
It is a matter for regret that those who are engaged in a geological
survey of a country do not also enjoy the advantage of some special
132 Reports and Proceedings—Geological Society of London.
paleeozoological training. It is, as a rule, difficult for a surveyor to
properly decide the exact age of the rocks among which he is
working, unless he is himself able to name his own collections. We
know that this was not formerly considered necessary even on
the Geological Survey here at home, and much of the confusion of
age which has arisen in various places is doubtless due to this
indifference to the high importance of a constant reference to palzeo-
zoological guideposts and zone-marks. The system which demands
that one man shall map everything from Archean ‘to Recent
doubtless debars many geologists from anything more than a super-
ficial acquaintance with fossils in the field, but that it is a necessary
consequence is disproved by many well-known Continental names.
The report is illustrated in an admirable manner, and plates iii
and vii (collotypes) are perfect, and show that Mr. Beadnell is
also an expert photographer. The three plates of wind-worn
pebbles are photogravures and excellent, but such ordinary objects
seem scarcely worthy of the expense incurred; certainly one plate
would have sufficed.
The Director-General of the Egyptian Survey and his staff may
well be proud of the stratigraphical results of their labours; and in
gracefully accepting the special knowledge of fossil forms afforded
them by Dr. Andrews, Mr. Bullen Newton, Professor Gregory, and
others, they cannot fail to enhance the high scientific value of the
palazozoological results obtained in this most interesting and ancient
country. C. D.S.
Ia HOwswyS} YNANAD) aA; ISYO(Ouap ADA (erS-
—
GroLoaicaL Society or Lonpon.
J.—January 21st, 1903. — Professor Charles Lapworth, LL.D.,
F.R.S., President, in the Chair. The following communications
were read :—
1. “The Figure of the Earth.” By William Johnson Sollas,
M.A., D.Sc, LL.D., F.R.S., F.G.S., Professor of Geology in the
University of Oxford.
The almost precise correspondence of great terrestrial features
with a circular form seems to be frequently overlooked. The
Aleutian curve has its centre in lat. 6° N., long. 177° W., that of
the East Indies about 15° N. and 118° E., and round the latter centre
are several concentric curves. The northern part of South America,
the Alpine-Himalayan chain, the western shore of North America,
and a portion of Australia may be similarly reduced to geometric
form. A great circle swept through the centres of the East Indian
and Aleutian arcs runs symmetrically through the bordering seas of
Asia as far as Alaska, borders the inland lakes of America, passes
the Californian centre, extends through the middle of the Caribbean
Sea, runs parallel with the coast of the Antarctic Continent, and
returns to the East Indian centre without touching Australia. This
course is in remarkable correspondence with the general trend of the
Reports and Proceedings—Geological Society of London. 133
great zone of Pacific weakness. If the pole of this circle in the
Libyan Desert is placed towards an observer in a globe, the African
Continent appears as a great dome surrounded by seas and separated
from the Pacific by an irregular belt of land. A second great circle
defined by Lake Baikal, and with its centre at ‘the morphological
centre of Asia’ of Suess, and passing through the Hast Indian centre,
may be regarded as the direction-circle for the Hurasian folding.
These two centres intersect at an angle of 39°, and, on bisecting this
angle, a mean directive circle is found, with its pole near the sources
of the White Nile, 6° north of the Equator. The axis of terrestrial
symmetry through this pole passes through the middle of Africa and
of the Pacific Ocean. The smallest circle which will circumscribe
Africa has its centre near this pole, and within it the symmetry of
the fractured African dome is observable. Outside this comes @ belt
of seas, and outside that again the Pacific belt of continents, the
Antarctic, South America, North America, Asia, and Australia.
Mr. Jeans has concluded on mathematical grounds that the ‘ pear-like
shape of the earth’ might have been possessed by it at the time of
its consolidation ; and he has suggested that Australia may represent
the ‘stalked end’ of the ‘pear.’ The author’s observations would
lead him to place it in Africa, and to regard the Pacific as covering
the ‘broad end.’
2. “The Sedimentary Deposits of Southern Rhodesia.” By
A. J. C. Molyneux, Esq., F.G.S.
The greater portion of the area of Southern Rhodesia lies on
granite and gneiss, and on the schists and slates that contain the
auriferous veins worked in ancient times, and now being again
opened up on an extensive scale. The remaining area is on sand-
stone and other sedimentary beds, with coal-deposits, and regions
of volcanic rocks. To explain the deposition and order of these
sediments several sections are given; one being along a line extending
from the Zambesi River on the north, through Bulawayo and the
central plateau, to the Limpopo River on the south, a distance of
over 400 miles. Another section, with remarks thereon, is copied,
by permission, from a report by Mr. C. J. Alford, F.G.S., on the
coal-bearing rocks of the Mafungibusi District.
From Bulawayo fine sandstones continue for about 170 miles to
the north, when there is a sudden drop in the surface of the country,
caused by a long line of cliffs of red sandstone, which extends from
the Zambesi Falls Road right across this portion of Rhodesia, and
finally merges into the Mafungibusi Hills far away to the north-east.
This is the great escarpment, formed by the erosion of 400 feet of
coarse grit with angular pebbles. To the north-west of this escarp-
ment, and running parallel with it, is a long and narrow valley
formed of soft shales which are known as the Matobola Flats. Here
the beds dip at 5° south-eastward. Thus, in proceeding further to
the north-west, underlying beds are revealed, with a lower series
of Coal-measures containing seams of workable coal. Below the
Coal-measures are quartzites and current-bedded grits, which rise up
and form the Sijarira Range, a flat plateau 15 miles across. Its
134 Reports and Proceedings—Geological Society of London.
north-western side, however, is almost precipitous, and is capped by
folds of quartzites. There is a drop of 1,100 feet in a few miles, and
the rest of the country is almost flat as far as the Zambesi River.
To the west is the gorge of the Lubu River, and it is there seen that
the sediments rest upon pegmatites and gneiss.
Another section shows the contact of fine sediments and meta-
morphic rocks down the railway-line to the south-west past Sisi
siding, where certain plant-remains were found. By these sections
the boundary or line of unconformity is traced from the Mafungi-
busi district, round the promontory of granites and shales which
form the backbone of Matabeleland, to the Tuli district and Sabi
River on the south. Except in the Tuli district, where an uncon-
formity between the veined sandstones and the Coal-measures is
noticed, there are no definite breaks in the order of stratification ;
and it is by the general arrangement of superposition and characteristic
features that the strata fall into certain groups. No attempt is made
to correlate the strata with the Cape and Karoo systems; and for the
present the author gives the following provisional classification :—
Thickness in feet.
Taba ’Sinduna Series ......... Sandstones and volcanic rocks ......
INOHOTB SEMGISOUES coonaesooacn +=. «| God apHERBUdHEOHADN (49700 1000
IBISCALP MENG GES Heese ele eee EGER cee eet seoeeee 400
Upper Matobola Beds ., Coal-measures..................eceeeeee 300
(fossiliferous).
TBE SEES soa copouasencnossHcos Sandstones and grits .............0.006 300
(fossiliferous).
Lower Matobola Beds......... Coal-measures...........-...c00e-0 0° ee) 200
SH EVBUE) SEINE, 45. onsasaccd00dd06 { Juouizteoemne) onerentlpaciied seme
SEOMCS Ie. blew -chclsdaccimeceeneaneseett 2000
Great unconformity.
Basement-rocks: Gneiss, schists, and pegmatites of Mafungibusi
and Lubu.
Fossils have been found in the Coal-measures, comprising mollusca,
plant- and fish-remains, which are described in appendices. These
indicate the age of these beds to be Permo-Carboniferous.
The Coal-measures yield coal of excellent quality, and the areas
in which seams outcrop, or have been developed, are described under
the names of the Mafungibusi, Sesami, Sengwe, Lubu, Sebungu, and
Wankies Coalfields in the north, and the Tuli and Sabi Coalfields in
the south.
Reference is made to the numerous mineral springs, of varying
temperature, that are dotted along the Zambesi Valley, and to
mounds of travertine, containing recent fresh-water and land shells,
that have been accumulated by extinct springs.
Voleanic rocks are well displayed in a long area extending from
Macloutsie to the Bubi River, 200 miles; and the extinct craters
are still recognizable at Fort Tuli, which gives the name to this
tract of Tuli Lavas. Sheets of basalt are interbedded with the
Forest Sandstones at the Bubi and Gwampa Rivers; and at a portion
of the escarpment above the Sesami Coalfield, basalt forms a capping
and extends back about 24 miles.
Three appendices are added: one, on a New Species of Acrolepis
Reports and Proceedings—Geological Society of London. 135
from the Sengwe Coalfield, by A. Smith Woodward, LL.D., F.R.S.,
F.G.S.; asecond, on some Lamellibranch Mollusca, by Wheelton
Hind, M.D., F.R.C.S., F.G.S.; and a third, on some Fossil Plants
from Rhodesia, by EH. A. Newell Arber, M.A., F.G.S.
IJ.—February 4th, 1903.—Professor Charles Lapworth, LL.D.,
F.R.S., President, in the Chair. The following communications
were read :—
1. “The Granite and Greisen of Cligga Head (West Cornwall).”
By John Brooke Scrivenor, Esq., M.A., F'.G.S.1
The small granite mass between St. Agnes and Perranporth has
been described by Conybeare, Carne, Sedgwick, Foster, and others.
It is a remnant of a much larger mass which has been partly
denuded by marine action and partly hidden by a north-and-south
fault. It is possible to distinguish two divisions of it; the main
mass and the ‘tongue,’ throughout both of which ‘bedding’ is
well developed. The granite bordering the bedding-planes has been
altered into greisen, which, owing to the abundance of quartz,
appears in the cliff-section as dark bands. Hach greisen band
contains a quartz-vein, marking the original fissure along which
metasomatism took place; the veins contain tourmaline, cassiterite,
wolfram, mispickel, and chalcopyrite. Two main reactions appear
to have taken place in the formation of the greisen; the felspars
affording topaz, muscovite, and secondary quartz; the biotite, brown
tourmaline, magnetite, and secondary quartz. The fact that no
tourmaline has been formed from the felspar, owing to the presence
of abundant fluorine, distinguishes this greisen from luxullianite
and trowlesworthite. The blue tourmaline prisms included in
original quartz appear to have been original constituents of the
granite. Secondary quartz, deposited in optical continuity with
the original grains, has also caused them to appear to have a crystal
outline. The fluorine and boron had not so great an effect on the
extremity of the tongue as on the main mass, as shown by the poor
development of greisen and the freshness of the biotite. Mica,
topaz, and microcline-perthite have been redeposited there by
percolating water or vapour. The greisen is an example of Professor
Vogt’s ‘pneumatolytic’ action in thoroughly acid rocks, resulting in
the formation of tinstone lodes, as contrasted with the similar action
in syenitic rocks with the production of zircon, etc., and in basic
rocks with the production of chlor-apatite and the scapolitization of
the felspar.
2. “Notes on the Geology of Patagonia.” By John Brooke
Secrivenor, Esq., M.A., F.G.S.
The author was travelling in Patagonia from September, 1900,
until March, 1901. The sedimentary strata consist of Tertiary,
Cretaceous, and Jurassic formations, which, with the exception of
the Jurassic, yield interesting and varied faunas, both vertebrate
and invertebrate. The latest classification is that drawn up by
Mr. J. B. Hatcher, who conducted the expeditions sent from
1 Communicated by permission of the Director of H.M. Geological Society.
186 Reports and Proceedings—Geological Society of London.
Princeton University. Mr. Hatcher, aided by Dr. Stanton and
Dr. Ortmann, has arrived at the following correlation :—
Shingle Formation eM aa Pebble- aac PLEISTOCENE.
Cape Fairweather Beds ... . ... PLIOCENE.
Santa Cruz Beds... ... ... ... ... ... Upprr Miocrne.
Patagonian Beds... ... ... ... ... Lower Miocene aud Upper OLiGocEnE.
Upper Lignites ... ... ... ... ... ... MIppLE OLIGOCENE.
Magellanian Beds ss ase a. «. LowkER Oxrcocens and UprEr Eocene.
Guaranitic Beds
Lower Lignites
Variegated Sandstones
Upper Conglomerates PCE EEE EE ORETACKOUSE
Belgrano Beds
Lower Conglomerates
Gio Beds
Mayer Shales... ... PEPE eate URASSTC.
Except in the rpHel where intrusions of an acid type have
disturbed the sediments, the southerly dip is so gentle as only to
be appreciable where sections can be followed for. some distance.
Mr. Hatcher considers that an unconformity separates the Magel-
lanian and Guaranitic Series, also the Cretaceous and Jurassic.
Excellent sections of the Patagonian Beds were seen on the Santa
Cruz River and in the coast-section at Monte Leon. ‘They are
littoral deposits, consisting of sandstones and mudstones. Calcareous
nodules are frequently arranged along the bedding-planes. Petro-
logically the sandstone is remarkable for containing fresh hyper-
sthene and plagioclase. At Monte Leon the top of the Patagonian
Beds is marked by gypseous mudstones and a shell-bed. These are
succeeded by estuarine beds, some of which yield impressions of
Fagus. Conformable on the estuarine beds are the famous Santa
Cruz Beds, which have yielded a rich vertebrate fauna. They
consist chiefly of pumiceous mudstones, with a little hypersthene ;
but a blue clay alternates with the mudstones, and there are also
two bands of Ostrea ingens, and one or two of ferruginous sandstone.
The Tébuelche Pebble-bed passes down into the Cape Fairweather
Beds imperceptibly ; otherwise it overlies everything unconformably.
Very little is known of the igneous rocks. Apart from those
of the Cordillera, there are vast plateaux of basalt and intrusions
of quartz-porphyry. A good example of the’ latter occurs at Port
St. Helena. The specimens of igneous rocks collected from the
moraines of the Cordillera comprise biotite-granite, hornblende-
granite, quartz-mica-diorite, gabbro, hornblende-picrite, quartz-
porphyry, rhyolite, obsidian, ophitic olivine-dolerites, olivine-basalts,
and acid tuffs.
The basalt-flows cover an enormous area. They slope gently
towards the Atlantic, and are cut off from the Cordillera by
a longitudinal depression. In the neighbourhood of Lago Colhuapé
there seems to have been a distinct centre of eruption, apart from
that which commences nearer the Cordillera. All that can be said
of their age is that they are older than the transverse depressions
‘of the Cordillera, and older than the glaciation of the eastern slopes
of that chain,
Reports and Proceedings—Geological Society of London. 137
The Téhuelche Pebble-bed, which covers nearly the whole of
Patagonia, has been ascribed to marine action by some authors, by
others to glacial action. A third suggestion is the agency of big
rivers. No one of these agents alone could have produced the
observed phenomena; the origin was complex. The bulk-of the
material was brought by glaciers from the Cordilleras to the sea,
which then covered the greater part of the pampas. As the sea
receded, it distributed the pebbles over the bottom, so forming
a continuous layer, such as now exists between the eastern coast
and the Falkland Islands. ‘Torrents resulting from the melting of
the glaciers assisted in distributing the material from the Cordillera.
Part of the material on the present eastern coast was derived from
islets of quartz-porphyry in the Pleistocene sea. A great difficulty
is that no basalt-pebbles are found at Santa Cruz east of the flows.
The drainage system includes several eastward-flowing rivers and
numerous lakes, some of which occupy transverse valleys cutting
through the Cordillera. An example of the latter is Lago Buenos
Aires. The history of this lake can be gathered from the evidence
observed on its shores. Lagos Musters and Colhuapé are two other
interesting lakes near the eastern coast. The width and depth
of the river-valleys are disproportionate to the present streams ;
this can be explained by a decreasing rainfall, and also by the
diversion of many tributaries to the Pacific. Some valleys are dry,
as, for example, the Great Canadon Salado.
3. “On a Fossiliferous Band at the Top of the Lower Greensand
near Leighton Buzzard (Bedfordshire).” By George William
Lamplugh, Esq., F.G.S., and John Francis Walker, M.A., F.L.S.,
F.G.S.
This paper describes a newly discovered fossiliferous band at the
top of the Lower Greensand, overlain by the Gault, in the sand-pits
at Shenley Hill, near Leighton Buzzard, in Bedfordshire. The
fossils of this band present a different facies from that of any other
previously known fossiliferous horizon of the Lower Greensand, and
show closer affinities with the fauna of the Upper Greensand than
have hitherto been recognized in any deposit below the Gault. The
Brachiopoda are closely allied to those contained in the Tourtia Beds
‘of Belgium. The fossiliferous bed is rather sharply marked off
from the underlying unfossiliferous ‘silver-sands,’ but is still more
sharply marked off from the overlying Gault. Stratigraphically it
forms part of the Lower Greensand, and cannot (without violence to
the accepted classification of the deposits) be considered to belong
to the Gault. The fossils constitute the newest Lower Cretaceous
fauna as yet recognized in England. Several species, hitherto sup-
posed to be confined to the Selbornian, are now shown to have been
in existence before the deposition of the Gault. The lithological
characters of the bed indicate a sea-bottom of moderate depth, swept
by powerful currents, and the conditions were thus similar to those
which persisted in the neighbourhood throughout Lower Greensand
times. The overlying Gault shows a change to more tranquil waters,
probably of greater depth.
138 Correspondence—Rev. Canon Bonney.
Ojeis iss SleuNpapssaNp @vsh
QUARTZ DYKES NEAR FOXDALE.
Sir,—Though I have not visited Foxdale in the Isle of Man,
T venture to express a doubt whether Mr. Lomas (p. 34) has succeeded
in proving its quartz dykes to be igneous rocks. ‘Dykes’ and veins
of that mineral are common in many countries, and cut almost all
kinds of rock, though, as might be expected, they are rather rare in
the more igneous or basic limestones. Sometimes the dykes attain
a considerable thickness and may be traced for a long distance; at
others veins run off into the finest threads, and their demeanour is
unlike that of an igneous rock, from which they are often far away,
and their abundant fluid cavities and consequent whiteness (as
described by Mr. Lomas) suggest that they have been formed
from water. ‘That silica, both crystalline and colloid, is so deposited,
especially from hot springs, is well known (see, for instance, a very
important paper by the late Mr. J. A. Phillips, published in the
Quarterly Journal of the Geological Society, vol. xxxv, p. 390).
The fact that at Foxdale quartz veins traverse the granite in itself
suggests they are later in origin and formed by thermal waters, with
which their occasional relation to dykes of microgranite is quite
consistent. Mr. Lomas appears to regard the fact that the veins on
entering the granite change locally into pegmatite as strongly in
favour of his bypothesis. But the presence of felspar or even
mica in a vein does not prove it to have had an igneous origin.
I have examined numbers of quartz-felspar-mica veins in gneissoid
rocks which seemed to differ in important respects from granite.
Sometimes, though by no means always, they have been affected by
the pressures which have produced the schistose structure; but the
three minerals are usually associated in a clotted and irregular fashion,
very different from that characteristic of rocks which have solidified
from a molten condition, and their structure frequently is abnormally
coarse, even in comparatively thin veins, where a true igneous rock
would be almost invariably either compact or not more than micro-
granular. The most remarkable case of mineral grouping which
I have seen was in the neighbourhood of Svolvaer in the Lofoten
Islands. Here a coarse gneissoid rock was cut by a quartz vein,
varying irregularly in breadth from two or three feet to as many
yards. By its side, and in places mixed with it, were a fairly broad
band of felspar and a much narrower one of a dark ferromagnesian
mineral, which at the time, more than thirty years ago, I took for
a pyroxene. The quartz was white and curiously divided by sharp
joints into parallelepipeds, rather variable in size. If, then, this
was an igneous vein, there must have been three distinct ejections
(only locally mixing) of quartz, felspar, and a ferromagnesian
mineral (not necessarily in the order of enumeration). The pegmatite
of the Foxdale vein, according to Mr. Lomas, contains felspars,
some over three inches long, perfectly formed, and showing crystal
faces. But the latter habit (except when there is considerable
difference between the fusion point of a mineral and the residual
Correspondence—J. Joly—Rev. Canon Bonney. 139
magma) is far more indicative of formation by water, and is not usual
in pegmatites, so far as I know them; if, indeed, all these are igneous
rocks. Mr. Lomas, however, may reply that he does not assert all
quartz veins, even if including felspar and mica, to be igneous, but
only that at Foxdale. But ifso, we may fairly ask him to tell us how
to distinguish igneous from aqueous veins. The former, when they
cut through sedimentary rock, especially if it be argillaceous, generally
produce rather conspicuous structural and mineral changes, so that
here I expected Mr. Lomas to give a careful description of the contact-
metamorphism or to offer an explanation of its absence. Instead of
this I find only the vague phrase ‘altered slate’—a phrase com-
patible with slight silicification or other changes such as may take
place by ordinary infiltration, and thus be no help to his hypothesis.
I do not deny that differentiation might possibly be carried so far in
an ordinary acid magma as to leave a residuum of pure or nearly pure
silica (though I have never met with an instance of it), but I think it
more probable that, as Mr. Lomas substitutes at critical points vague
phrases and inconsequent statements for precise description, he has
yielded to the fascination of a novel hypothesis.
P.S.—The above was written before the publication of Mr. Harker’s
letter (p. 95). T. G. Bonney.
THE ORIGIN OF QUARTZ-VEINS.
Srr,—In connection with the question of the origin of certain
quartz-veins,’ the fact that quartz reveals plastic qualities at
temperatures considerably below the melting-points of many
undoubted igneous minerals must be born in mind. J. JoLy.
Trinity Conurcs, Dusiin.
February 9th, 1908.
NEW GEOLOGICAL TERMS AND FALSE ETYMOLOGY.
Str,—As no one seems inclined to protest against the terms
‘calcrete ’ and ‘silcrete’ with which Mr. Lamplugh proposes (in your
December number’) to disfigure geological nomenclature, I must
even raise a voice in the desert. Brief expressions for what he
intends them to convey would doubtless be useful, and no one would
be likely to quarrel with ‘calcicrete’ and ‘silicicrete,’ of which one
would be two, the other three, letters longer. I admit that public
convenience may sometimes prevail over strict etymological rules,
as in preferring the inaccurate ‘telegram’ to ‘telegrapheme’; but
‘calerete’ and ‘silcrete’ are even worse than the fashionable
mongrel ‘ peneplain,’ and approximate in malformation to the hideous
‘phenocryst,’ which seems invented to signalize the divorce of
geology from culture. T. G. Bonney.
THE DEHYDRATION OF LATERITE.
Sir, — The very interesting paper on “The Constitution of
Laterite,” by Mr. T. H. Holland, appearing in your issue for
February, 1903, raises several questions of chemical physics which
1 See Mr. J. Lomas’s article, Grotocican Macazinz, January Number, p. 34,
and Mr. Alfred Harker’s letter, February Number, p. 95,
* Geox. Mac., December, 1902, p. 475.
140 Correspondence—ZJ. V. Elsden—J. R. Dakyns.
are of the utmost importance from a geological standpoint. That
crystalline affinity is a definite molecular force accompanied by
exothermic changes is doubtless correct, but whether this force
can determine chemical changes of an endothermic character is
a question involving an entirely new conception, and requires
careful consideration before it can be accepted as a reasonable
hypothesis. More especially is this the case when we have to deal
with the constitution of hydrates, which afford such excellent
examples of the application of the phase rule in chemical physics.
Hydrates, as is well known, have a vapour pressure of their own,
and only continue to exist when in equilibrium with the vapour
pressure which they have to support. ‘Thus the hydrates of copper
sulphate can be successively decomposed under varying conditions
of temperature or pressure. The instability of the aluminium
hydrate, Al,O,.3 H,O, at moderate temperatures, also, is a fact
well known in chemistry ; and it seems probable that the occurrence
of any hydrate, either of aluminium or of iron, in nature will
depend upon which happens to be the stable phase under the
existing conditions of temperature and pressure.
In connection with the crystallization of alumina the researches
of W. Spring, of Liége, appear to have some bearing. According
to this observer, amorphous alumina or ferric oxide, if damp, can
be rendered compact, presumably with the occurrence of an incipient
crystallization, by pressure alone; and we are induced to consider
whether the amorphous state in solids may not, in some cases at
least, be comparable with the condition of superfused solutions and
glasses. In fact, many of the distinctions between solids and
liquids are gradually breaking down under the researches of
modern physics.
There does not, therefore, appear to be any necessity for a new
theory to explain the facts in this case. It appears rather that
Mr. Holland has unnecessarily introduced a difficulty by presupposing
that the molecules in laterite are isolated from extraneous energy.
If this were really the case there could be no change of entropy
such as he describes, and rightly, to be the result of the reactions
involved. J. Vincent Espen.
88, St. STEPHEN’s GARDENS, TWICKENHAM.
THE COLOUR OF GLASLYN AND OF LLYN LLYDAW.
Sir, — Glaslyn and Llydaw are the names of the two chief
Snowdonian tarns. Glaslyn has been noted from time immemorial
for the greenish colour of its water, as is implied by its name; but
until the Summer of 1899 there was nothing peculiar about the
colour of Liydaw. During that Summer, however, for the first time
within the last fifty years at least, the water of Llyn Llydaw became
as green as that of Glaslyn. The cause of this remarkable change
of colour is not far to seek; for in the Spring of 1899, some time
about March I am told, the company that works the Snowdon
Copper Mine commenced crushing and washing their ore on the
bank of Llydaw, so that a large quantity of greenish débris was
Correspondence—A. J. Jukes-Browne. 141
and is daily carried into the lake, whose water has thus become
turbid and greenish in colour. The rock excavated along the copper
veins is of a greenish colour, as may be seen by looking at the tips
from the adit-levels.
This change of colour in Llydaw explains the colour of Glaslyn,
about the cause of which there has hitherto been some doubt. For
it cannot now be doubted that Glaslyn owes its green colour to
the detritus of green rock washed into it from the adit-levels of
the mines. J. R. Daxyns.
P.S.—I should say that the mines are situated immediately above
Glaslyn.
Snowpon View, Nant Gwynant, BEDDGELERT.
January 21st, 1903.
THE TERM ‘HEMERA.’
Srr,—Mr. Buckman appears to think that stratigraphy is nothing
but geological chronology i.e., that it is chiefly concerned with the
days and weeks of geological time, and that the actual sequence of
rocks is of less importance.
He will not admit that his definitions of the term hemera, or his
correlation-table of zones and hemere in Quart. Journ. Geol. Soc.,
vol. xlix, p. 519, are open to misconstruction, and yet he complains
that most of those who have essayed to use his term have misunder-
stood the meaning he intended to give it. It now appears that in
that table he was giving us a geological calendar, and not an ordinary
correlation-table of rock-subdivisions.
The real fact is that Mr. Buckman gave a name to an abstract
idea relating to a thing which had no definite name at the time when
he wrote. His paper was a stratigraphical one, and he cannot deny
that he was actually dealing with the subdivisions of zones, yet,
instead of proposing a name for the small subdivisions which he
recognized in the sequence of deposits, he gave a name to the time
occupied in the formation of each subdivision; in other words, he
saw no necessity to give a name to the thing itself, but only to the
geological day or week in which it was formed.
He asserts that he was giving a name to the duration of a zone,
but this assertion is inconsistent with his original definition of
a hemera; he says, ‘‘successive hemerz should mark the smallest
consecutive divisions which the sequence of different species enables
us to separate in the maximum developments of strata.” Now, a zone
is not the smallest possible subdivision of a series of beds, and
Mr. Buckman’s own tables show that he knew it was not, for they
show that it took the time of two or three hemere to form one zone.
Hence, if a hemera is anything at all it is not the duration of a zone,
but of some subdivision of a zone.
The only point that Mr. Buckman has made quite clear is, that he
will not have his term ‘hemera’ used as the name of a rock-division,
but he has not clearly indicated with what recognized subdivision of
a stage he wishes the term to be connected. If he makes any reply to
this letter, let him state clearly whether he accepts the term subzone,
142 Obituary— Henry. Stopes, F.GLS.
and whether he intends the word hemera to denote the duration of
a subzone. If he does, then I can safely promise that he shall not in
future be annoyed by my misuse of the term, for I will take care
never to use it except on those infrequent occasions when I want to
express the time during which a certain subzone was formed. My
chief concern is with the actual stratigraphical unit and the fossils
which it contains; a name for the time-unit may be convenient, but
is of quite secondary importance. Hence his reductio ad absurdum
does not trouble me. A. J. JuKkES-BRowns.
Torquay, February 4th, 1903.
OBITUARY.
HENRY STOPES.
Born Frpruary 17, 1852. Diep DrcremBer 5, 1902.
We regret to record the death, on December 5th, 1902, of
Mr. Henry Stopes, for many years a Fellow of the Geological
Society of London. He was born at Colchester on Feb. 17th, 1852,
and it was perhaps his early association with that ancient place
which turned his thoughts to antiquities. When a boy of 8 he found
a fossil Hchinus in the playground gravel, and after seeking in
vain from all he met an explanation of its peculiarities, he took it
to bed with him, that he migbt meditate at leisure in the morning
over its meaning. For this he was punished, but the punishment
only intensified his interest, and he kept that stone, which became
the nucleus of a large geological collection. He early brought
together a fine series of Essex Crag shells, part of which is now
on loan at the Stratford Museum. While collecting this, he received
from a friend, a fellow-collector, a specimen of Pectunculus glycimeris,
which the latter had himself taken from the Red Crag at Walton-on-
the-Naze, with a rude carving of ahuman face onit. Mr. Stopes read
a short note on this at the British Association Meeting at York, 1881
(see Report, p. 700). The carving has not been generally accepted
as conclusive by all geologists and anthropologists in England,
but some French anthropologists have done so. It is mentioned
in Keane’s “ Ethnology,” p. 78. Mr. Stopes considered that the
carving suggested pre-Glacial man;* he was the first to set to
work to disprove or verify it, and it thus determined the direction
of his later researches. He took a house near the gravel-pits of
Swanscombe, where he made many interesting discoveries, notably
that of the association of Paleolithic implements in a sand-bed there
with Neritina fluviatilis and other extinct species of shells (see his
paper in the Journ. Anthrop. Inst., xxix, p. 302). He has collected
an enormous number of stone tools, chiefly Paleolithic. His first
paper on “The Salting Mounds of Essex” was read before the
Hssex Antiquarian Society, Dec. 20th, 1884, and was published in
the Hssea Naturalist, April and May, 1887. He read many papers
1 [It must be borne in mind that the drawing on the shell from the Crag of Essex
is open to the same objection as is the cut bone of a Cetacean from an Italian
Tertiary deposit, also attributed to man’s handwork, namely, that both deposits are
marine.—Eptr. |
Obituary— Alfred Vaughan Jennings, F.L.S., F.GS. 148
before the Anthropological Section of the British Association and
several before various Geological and Literary Societies.
_ He wrote some articles and reviews for the Atheneum and other
Journals. His enthusiasm kindled interest in his researches among
all he met, friends or workmen alike. When the complaint from
which he suffered was found to be consumption, he was ordered to
try open-air treatment, and he would go nowhere else than to the
scene of his researches. He was buried near Old Swanscombe Church
on December 10th, and the workmen of the village feel they have
lost a friend.
ALFRED VAUGHAN JENNINGS,
Assoc. R.S. Minzs, F.L.S., F.G.S.
Born Aprit 17, 1864. Diep Janvary 11, 1903.
ALFRED VAUGHAN JENNINGS was born at Hampstead, and educated
at St. Paul’s School. He matriculated at London University 1877,
and entered as a student at the Royal School of Mines under
Professor Huxley, etc., where he was bracketed first in Advanced
Zoology with Martin F. Woodward in 1885, and received the
Edward Forbes Medal and prize of books for Biology in that year.
He was for three years Demonstrator in Geology with Professor Judd,
F.R.S., undertaking at the same time to instruct privately, in his
own laboratory in Chancery Lane, a class of students in Biology,
preparing for the B.Sc. London University Examination. He also
taught occasional classes in Botany at the Birkbeck Institution.
It was the passionate earnestness with which he taught and
inspired these young men which first betrayed his abnormally
nervous temperament and weak heart. The work of teaching, for
which he inherited a genius, had in consequence to be given up.
Six months were then spent beneficially in a voyage and visit to
New Zealand. On his return in 1890 he undertook the arrangement
of the new Museum about to be opened at Eton College; and after
the death of Dr. P. Herbert Carpenter he was offered by Dr. Warre,
Head Master of Eton College, one of Dr. Carpenter’s classes, in
addition to the permanent care of the Museum. This he was
compelled to decline, as the doctors still forbad his teaching, and
residence at Eton had already proved mischievous to his health.
In 1892 he took charge of the Museum then opened at Whitechapel.
In 1895 he removed to Dublin, where for three or four years he
assisted Professors Cole and Johnson with the geological and
botanical classes at the Royal College of Science. But teaching
had again to be abandoned. He subsequently went to Davos Platz,
and later to Bad Nauheim, from which places he sent papers to the
Geological Society and to this Magazine, viz. :—
Jennings, A. V.—‘‘On the Courses of the Landwasser and the Landquart”’ :
Grou. Mac., 1899, pp. 259-270, with three illustrations.
“The Geology of the Davos District’’: Proc. Geol. Soc., May 10, 1899 ;
Grou. Mac., 1899, pp. 326-327; Quart. Journ. Geol. Soc., 1899,
vol. lv, pp. 381-412, pls. xxvi and xxvii, map, and section.
—— ‘The Geology of Bad Nauheim and its Thermal Salt-Springs’’?: Gxrou.
Mag., 1900, pp. 349-366, with six illustrations.
144 ~ Miscellaneous.
His last year was spent mostly in Christiania, where, in spite of
much physical suffering—caused by a tramcar collision, which
confined him to hospital for some time—he was working to the end.
MIiSCHUiuGaAN BOUS.-
——
Toe New Director or tHE GeoLtogicaL SurvEY or Inpra.—
Mr. C. L. Griesbach, C.I.E., F.G.S., who has filled with distinction
the office of Director of the Indian Geological Survey in Calcutta
since the resignation of Mr. King on 17th July, 1894, retired under
the age limit on December 11th, 1902, and we learn with much
pleasure that Mr. T. H. Holland, Assoc. R.C.S., F.G.S., has just
been appointed to succeed him. Only in our February Number,
Mr. Holland contributed what may be without exaggeration
described as an epoch-making article “On the Constitution, Origin,
and Dehydration of Laterite,’” which is already attracting the
earnest attention of Indian and other geologists in this country.
Thomas H. Holland received his scientific training in the Royal
College of Science, South Kensington, between 1885 and 1888. He
passed his examination as associate with honours, and was awarded
the Murchison Medal of the Royal College of Science in 1887.
Mr. Holland joined the Geological Survey of India in 1890, and
was appointed Professor of Geology and Mineralogy at the Presidency
College, Calcutta, in 1893. He has already contributed numerous
papers of high scientific value to the Records and Memoirs of the
Geological Survey of India, the Royal Asiatic Society, Calcutta,
the Mineralogical Magazine, the Geological Magazine, and the
Quarterly Journal of the Geological Society of London.
Mr. Holland has shown himself to be an acute and accurate
observer, both in the laboratory and in the field, and his con-
tributions to Mineralogy and Petrology contain careful work of
a very high order. His memoir on the Charnockite Series is
a classical contribution to the study of the Archean rocks of
Southern India.
His papers on the igneous eruptive rocks of Salem at Canoor and
the eleolite-syenites of Coimbator are also valuable contributions
which have added greatly to our knowledge of the crystalline rocks
of Peninsular India.
Mr. Holland has been selected at the early age of 34 to fill the
important office of Director of the Geological Survey of India.
We congratulate him on his promotion, and Government on
having obtained an energetic and reliable officer of such high
promise to fill this important post. Mr. Holland has our best
wishes for the success of his future career.
Erratum: p. 94, last line but one, for Professor G. B. Fletcher read J. B. Hatcher.
1 He wrote to the Editor at Christmas, offering him an article for the GkoLogicaL
Macazine on the Geology of the Christiania district.
THE
GHOLOGICAL MAGAZINE.
NEVVSERIESs a DECADE IN VO EL Xe
No. IV.— APRIL, 1903.
OEE GaN AC ass | AES ae arse Se
=
J.—Tue Devetopment or River Meanpers.
By Professor W. M. Davis, Harvard University, Cambridge, Mass.
HE paper by Dr. Callaway, ‘On a Cause of River Curves,”
in the GrotogicaL Magazine for October, 1902, suggests
comment for two reasons: first, because the cause that he brings
forward seems of doubtful application ; second, because the habitual
entrance of branch streams at a certain part of the curves of
main streams is satisfactorily explained by controls which seem to
be of surer and more powerful application than the control which he
advocates.
In ascribing to a tributary the power to make a main stream bend
in a definite manner towards the tributary, and thus determine the
habitual entrance of tributaries on the convex side of the main
stream’s curves, Dr. Callaway argues that the detritus brought by
the tributary will be deposited on the further side of the main
stream and somewhat below the tributary’s mouth. Various
examples known to me of the deposits formed by side streams in the
channels of main streams do not bear out this conclusion: the
detritus is not deposited on the further side of the main stream, but
as a delta at the mouth of the tributary or a little below it; and the
main stream does not bend toward, but away from the tributary.
The Rhine, the Colorado, and many other rivers that might be
instanced, show abundant examples of this kind. Moreover, the
assumption of an initially straight main river, as stated by
Dr. Callaway, involves an extreme improbability. Rivers cannot be
habitually straight in their initial stage, and the bends with which
they begin are as a rule spontaneously exaggerated in their later
development. The processes by which the initial bends are
developed into meanders, and by which the meanders are persistently
maintained when once developed—entirely independently of the
action of tributaries,—are too important to be omitted from the
problem in hand: above all, they should not be replaced by
a doubtful or at most a weak process.
DECADE IV.—VOL. X.—NO. IV. 10
146 Professor W. M. Davis—River Meanders.
The most important process in the development of river meanders
is the displacement of the line of fastest current by inertia from mid-
channel toward the outside of every curve. As a result erosion
tends to take place on the outside and deposition on the inside of the
curve. This process is self-perpetuating. However slight the
initial bends, they will be increased; and as the valley floor is
broadened the curves will be developed into systematic meanders
of increasing radius and breadth, as in Fig. 1. The only conditions
under which the river course will tend to straighten itself are:
strong tilting in the direction of river flow, and downward erosion
upon a weak stratum between two resistant strata in an inclined
structure. Both these conditions are only temporary ; for as grade
is reached in either case and the valley floor is widened, the residual
departures from a perfectly rectilinear course will be exaggerated
again, and in advanced maturity the river must always be curved.
The smaller the stream, the greater the effect of accidental causes,
such as falling sods and trees, tributary deltas, etc., in forming new
bends. The larger the river, the greater the effect of inertia in
exaggerating pre-existant bends and in overcoming local or accidental
irregularities.
ErGale.
A river not only tends to increase its meanders; it also tends to
push the whole meander system down the valley. This is because
the line of fastest current, displaced toward the outside of each curve,
enters the succeeding curve (or stretch between two curves) near
the down-valley bank, which is therefore worn away, while the
opposite up-valley bank is built out. As a result, Fig. 1 should
be modified by a persistent down-valley migration of every bend,
as in Fig. 2. Cut-offs occur now and then, here and there, but,the
shortened course at a cut-off is not straight, and its faint curves are
Professor W. M. Davis—River Meanders. 147
soon systematically exaggerated into meanders again. Abundant
verification can be given of this scheme of development, by observing
the behaviour of actual rivers, or more simply by studying the new
edition (1900-1901) of the preliminary maps published by the
Mississippi River Commission at St. Louis, Missouri, on- which
the river channels as determined by surveys in 1893-5 are over-printed
in red upon the results of surveys in 1881-3, printed in black.
ETGaroe
Any river that we now see meandering in an open alluvial plain
must have been meandering a long time. Its individual meander
curves must have already advanced down the valley over considerable
distances; and it is, I believe, chiefly for this reason that tributaries
are taken in where the main stream bends toward them. To make
this clear, let a number of tributaries be added at random to the
latest river course, drawn in Fig. 2, Four of them are shown in
Fig. 3: one enters the river at a convex bend, the other three at or
near concave bends. Now let the normal changes of the meanders
continue still farther, as in the dotted lines of Fig. 4. In the first
of these changes, tributary D is taken in by the convex curve next
above the concave curve that it entered before. In the second change,
the mouth of the tributary B is similarly transferred to a convex
curve. In the third change, the same fate overtakes tributary A.
During all these changes, tributary C has been only a little shortened ;
it still enters on a convex curve. When this curve comes to move
down the valley the tributary will prolong its course, but will
continue to enter the main stream on the up-valley side of a curve,
until it is captured by the approach of the next following curve.
It therefore appears natural enough that tributaries should usually
148 Professor W. M. Davis—River Meanders.
enter the main river meandering freely on a flood plain where its
curves turn toward them.
The simplest conditions under which a tributary should be led
to enter its master at an abnormal point are found in the occurrence
of a cut-off, asin Fig. 4; but this special case would soon be brought
under the rule, either by the development of a new meander which
will usually grow towards the tributary in the neighbourhood of the.
cut-off,’ or by the approach of the next up-valley meander.
A second group of examples would include rivers that follow
relatively narrow meandering valleys, like those of the lower Wye,
the lower Seine, the lower Moselle, or the north branch of the
Susquehanna. Here the same rule may be expected to apply to the
entrance of the tributaries, and that for two reasons. In the first
place, because such rivers have, it may be said with much confidence,
incised their meandering valleys from a meandering course that they
formerly possessed on the upland in which the valleys are incised,
when that upland was a lowland of erosion. On such a lowland the
rivers must have reached a late stage of their cycle of development,
and in a late stage they must have been meandering freely. While
the uplift was going on and afterwards, the meanders would have
been incised beneath the uplifted lowland ; but the entrance of the
tributaries has not been thereby significantly altered from whatever
orderly arrangement they had gained during the former lowland
stage of erosion.
In the second place, if by chance any abnormally entering
tributary existed when uplift and incision began, the normal processes
of widening the meander belt and of shifting the meanders down-
valley, which must accompany incision, would sooner or later bring
about a normal entrance in the same manner as on an alluvial flood
plain, shown on Fig. 3, but at a lower rate than there obtains. An
excellent instance of this kind is known in the lower Seine, where
the Ste. Austreberte has been taken in at Duclair, not far below
Rouen, precisely as illustrated in Fig. 3.
Another instance of the same kind occurs on the Marne not far
east of Paris (see “The Seine, the Meuse, and the Moselle,” Nat.
Geogr. Mag., 1896, vii, 191). The Moselle exhibits at least one
illustration of the entrance from the south-east of a small tributary,
the Veldenzer Bach, on a concave stretch a short distance up-stream
from Berncastel ; but this is demonstrably the result of a cut-off, as
shown in Fig. 4 (ibid., pl. xxii, opp. p. 193).
These normal, effective, and fully verified habits of change in the
course of a meandering river seem to account very fully for the rule
that tributaries usually enter where the river curves toward them ;
a rule that Mr. Callaway shows to obtain for various rivers in many
parts of the world, and that is supported by certain additional
examples that I have recently inspected.
1 The changes following the occurrence of a cut-off, as illustrated on the maps of
the Mississippi, show that the growth of a new meander towards the cut-off and
abandoned meander, but a little further down-valley, is not unusual.
W. H. Hudleston—Creechbarrow in Purbeck. 149
II.— CrercHBaRkRow IN Purseck.—No. 2.)
By W. H. Huprzston, M.A., F.R.S., F.G.S.
ADDITIONAL Porn’rs IN STRATIGRAPHY.
N my paper published in the Proceedings of the Dorset Field Club
(vol. xxiii), I dwelt at some length on certain borehole sections
made towards the northern base of Creechbarrow with a view to the
discovery of Pipeclay. This course was adopted in the hope that
a study of these sections might throw some light on the strati-
graphical relations between the Creechbarrow Beds on the hilltop
and the Pipeclays lower down, if indeed there are any strati-
graphical relations beyond a mere jumble of irregular deposits whose
precise orientation can never be disentangled. Whether this latter
supposition is the true one or not, the exceptional character of the
Creechbarrow Beds, as a local feature, remains the same, even
although we cannot decide whether they go under, over, or into the
Pipeclay series. Before attempting any further speculation as to
the possible stratigraphy of the region I will call attention, at any
rate, to its topography as shown in the accompanying figure.
LLZE LL
Wo eee
Ze
ty Yi
G7
ZZ__Pipe-clay Series
E==]__Creechbarrow-beds
eseqd__Chalk
Fic. 1.—Creechbarrow from the north-east, based on a photograph by the late
Mr. Laurence Pike.
A. Summit of Creechbarrow, 637 feet.
B. The eastern spur.
G. The northern ridge (approximate dip slope). The hilltop limestone extends
along this ridge as far as the 500 feet contour.
DD. The Purbeck Hill; maximum elevation 654 feet, just behind Creechbarrow.
KE. Blackhills Plantation, about the 300 feet contour.
F. Spoil-heaps of the clay workings.
North-East Side of Creechbarrow: Additional Particulars as to the
Creechbarrow Beds.—From the above figure the topographical
relations of the Creechbarrow Beds to the Pipeclay series can be
seen at a glance; the former looks down upon the latter. It is
1 No. 1 appeared in the June number of the Gronocircan Macazrne for 1902.
It was then intimated that the subject would be treated more fully in the Proceedings
of the Dorset Field Club. This has been done, and a portion of the additional matter
is now, by the kind permission of the Publication Committee of the Dorset Field
Club, reproduced in the Gzotocicat Macazine. This portion relates mainly to the
lithology and paleontology of the Creechbarrow Beds.—W. H. H.
Plate XI, illustrating this paper, will appear in the May number with the remaining
part of the article-—Hpir. Grou. Mac.
150 W. H. Hudleston—Creechbarrow in Purbeck.
scarcely necessary to point out that the Purbeck Hill (DD),
consisting of Chalk, is depressed by perspective, the highest part of
it slightly exceeding the height of Creechbarrow. A word as to the
composition of the Creechbarrow Beds seen in this figure may be
useful as a sort of recapitulation of what has already been stated.
If I give this in the form of a generalized vertical section, it is
merely for the sake of convenience, and not to be regarded as
absolutely true at any one point.
1. The highest bed of the series is the deposit on the
Creechbarrow Limestone. With this must be associated the beds
above the ‘marl’ detailed in the northern section. The thickness
of these latter beds is about 13 feet down to the ‘main marl,’ and
they consist of sands, clays, flints, and a thin bed of ‘ marl.’
2. The next in downward succession is the hilltop, or Creech-
barrow Limestone, which is excessively hard at the summit (A),
but becomes softer when traced on the dip slope towards the
200 feet contour (the letter C is approximate) ; in this condition it
is known as ‘ marl,’ and may be about 12 feet thick in some places.
3. The beds immediately below the Creechbarrow Limestone
are extremely variable, and constitute a stratigraphical crux of
considerable perplexity. They certainly differ materially within
short distances, and but little analogy can be traced between those
on the south side of the summit and those on the north side, which
are below the 500 feet contour. On the south side of the summit
these beds have been traced in detail with considerable accuracy for
about 20 feet vertical, and this must be regarded as the standard
section.
On the whole, we may sum up by stating that the beds
immediately below the summit Limestone, for a vertical extent of
perhaps 380 feet or more, are sandy, with some yellow clay,
frequently manganiferous, and are characterized by numerous beds of
flints, the beds ranging from 6 inches to 3 feet 6 inches in thickness ;
loose flints also occur in the sands.
In further illustration of this class of beds I would direct attention
to the eastern spur of Creechbarrow (B of Fig. 1). This spur is
a conspicuous object from the north-east side, since it breaks the
regularity of the conical outline as seen from Furzebrook.
Being desirous of finding some evidence as to the cause of this
slight local prominence, I had a special pit sunk on the very top of
it, with the following result :—
Pit ON THE EASTERN SPUR OF CREECHBARROW. Beso.
a. Sandy earth with flints 0 6
b. Flint-gravel ... one me ae boc ne: 3 6
c. Buff, ferruginous sand with manganese nodules ... 2G
Total section 669 6 6
The flint-gravel (b) of this section is the thickest deposit of the
peculiar ‘gravel’ of Tertiary age as yet discovered on Creech-
barrow ; water was lying in the bottom of the pit, apparently due to
a pan formed by surface action. The extent of the opening scarcely
W. H. Hudleston—Creechbarrow in Purbeck. 151
permitted us to ascertain whether there is any bedding in the
‘gravel.’ The stones are of very unequal size, varying from flints
30 lb. in weight to quite small stones; I did not at the time notice
any pebbles. The character of the flints here is just the same as in
all the Creechbarrow Beds ; the large ones have a partially rounded
exterior consisting of white silica thoroughly degelatinized. Some
are degelatinized throughout, others have a brown core of gelatinous
silica still left; most of them are very brittle and fly to pieces
on being struck by the hammer. At present it is not possible to
connect this particular bed of flints with those found in the pits
near the summit. That there are beds of flints occurring in
stratigraphical relation to the sands and clays of this hill is certain,
and they probably occur on several horizons. The manganese
nodules in the buff, ferruginous sand are very interesting and fairly
abundant. I shall refer to them again when dealing with the
lithology of the Creechbarrow Beds.
The evidence obtained in this pit on the eastern spur goes to
confirm the supposition that the abundance of bedded flints of
Tertiary age in the upper part of Creechbarrow has materially
assisted the limestone in preserving the softer sands and clays from
denudation. Such an observation may be accepted as a general one,
applicable more or less to the whole hill. When we come to
particulars the limestone is more especially accountable for the
summit (A), whilst the unusual accumulation of flint ‘gravel’ is
more directly the cause of the eastern spur (B).
3. The Buff-coloured Clay. —Still dealing with the deposits
immediately below the limestone and ‘ marl,’ we have seen that, on
the northern slope and some distance below the 500 feet contour,
the calcareous series rest on a few feet of sands with flint-gravel,
and that below this comes a very important deposit of buff-coloured
clay (Mr. Bond’s clay-pit), which may occur as a lenticular mass, as
it does not appear to have any representative if followed in the
direction of the eastern spur.
4. The lowest member of what I have termed the Creechbarrow
Beds are the ‘Sands’ underlying the buff-coloured clay. These
can be studied at Mr. Bond’s sandpit, where the following section
may be noted :—
CreEecH SANDPIT.
ft. in.
a. Clay with rootlets he iG
6, Clay passing into sands ; flints occur, especially towards
the base (? Be : sich i ss 5 6
c. Bedded sand . a6 1 3
d. Yellow clay Ww ith lar: ee flints at base ‘and a pink line 1 0
e. Yellow variegated sandy clay with a few small flints 1 6
f. Salmon- coloured sand with a black centre line, the colora-
tion probably due to manganese 0 3
g. Very fine white sand with but little true bedding (not
bottomed) an oe oe)
20 0
N.B.—a and #4 represent the base of the Creech brickearth or buff clay.
& ;
152 W. H. Hudleston—Creechbarrow in Purbeck.
This concludes the description of the Creechbarrow Beds as far as
I have been able at present to trace them. If we turn to Fig. 1
we perceive that the convenient obscurity afforded by the Blackhills
Plantation helps to conceal their possible relation to the Pipeclay
series ; all we can say is that, topographically speaking, they occupy
the higher ground, and that when we get well below the 300 feet
contour the Pipeclay series has possession of the surface.
LitHoLnocy AND PALmoNTOLOGY.
The big Flints.—Before entering upon a detailed description of the
Creechbarrow Limestone, there are some other matters of interest
which may be considered. The first of these refers to the very large
flints which have contributed in no small degree to the maintenance
of the fabric of Creechbarrow, and which are such an exceptional
feature in the Bagshot beds of this immediate district: their strati-
graphical relations may be gathered from the preceding pages. As
Fic. 2.—One of the manganese nodules from the eastern spur of Creechbarrow.
Reduced } (from a photograph).
regards the general character and appearance of these flints, they are
for the most part of a dirty cream-colour; they are also much
degelatinized, and in some cases the exterior is simply a mass
of granular silica, very meagre to the touch. They are also
extremely brittle when first dug out, though it is probable that
exposure to the atmosphere toughens them after a while. In
consequence of this brittleness the available fragments do not much
exceed 28 lb. in weight, so far as I have seen them, though it may
well be that heavier flints than these occur. These flints have split
in the bed itself. The surface of those flints which are not much
broken has been subject to very little modification from abrasion.
Associated with the big flints are flint pebbles and other stones
of moderate size, also quartzose grit.
The peculiar fawn colour of these siliceous masses will help
to distinguish them from ordinary plateau-gravel or valley-gravel
W. H. HER ioN ee Oveconbarnors in Purbeck. 153
flints; and the amount of soft and almost pulverulent material
which coats so many of them is a further distinction, as this
substance could never endure the wear and tear of the gravel-
making processes. Without illustration, which would necessitate
the employment of colour, it is by no means easy to convey an
adequate idea of the peculiarities of the big flints, when freshly dug
out of the beds which contain them. Their general appearance
leads one to suppose that they had been subject to some corrosive
action, and this is especially noticeable where there are any
dndications which may have been due to organic bodies, such as
urchins or sponges.
When these Creechbarrow flints have been rolled down the
hillside, and subjected to atmospheric action, the external coating of
loose silica is found to have been entirely removed, and the flint
itself bleached to a dirty white condition, though the casts of Pectens
and other fossils still retain traces of iron-discoloration.
Fie. 3.—Part of a calcareous nodule from No. 4 pit. Nat. size.
The Manganese Nodules.—There are considerable traces of black
oxide of manganese both in the clays and limestones of Creech-
barrow, but the remarkable nodules which I am about to describe
‘have only been found in the yellow sand underlying the great flint
bed on the eastern spur (see p. 152). Here the most beautiful
botryoidal masses of this black oxide, which is probably the hydrated
peroxide, or psilomelane, are common and of great variety in form.
The one figured has a length of five inches, and its specific gravity
considerably exceeds that of the manganese nodules which are
figured in the description of the voyage of the ‘“Challenger.”* In
other respects there is a general resemblance, the chief difference
being that in our case ordinary quartzose sand functions as the
material caught up by the mineral instead of fine pumice and
volcanic fragments, ete., as in the case of those found at the bottom
of the Pacific. I have not seen any nodules from the Pacific where
the mamille are so salient or so rough as those from the east spur of
‘Creechbarrow, which are handsomer in shape, heavier, and present
' Deep Sea Deposits, pl. ii.
154 H. & F. J. Warth—On Indian Laterite.
greater contrast of colours. It is evident that great depth is not
absolutely necessary to the formation of manganese nodules, as the
Creechbarrow Beds, being associated with fresh-water limestone, could
not be other than shallow-water deposits, whilst the manganese
nodules from the bottom of the Pacific Ocean were formed in depths
between 2,500 and 3,000 fathoms.
The Creechbarrow Limestone. — Perhaps the first stage in the
description of this curious rock should be an illustration of the mode
of its growth in the associated sands. This may be well studied in
No. 4 pit, where there were several calcareous nodules just under-
neath the irregular base of the great mass of limestone. The one
figured (Fig. 3, p. 153) may be deemed characteristic.
Externally there is a kind of skin made up of very closely set
calcitic layers, which have a rough exterior and include a few
sand grains. The rest of the nodule consists mainly of carbonate of
lime with a small amount of very fine mechanical sediment. In
this respect it differs greatly from the manganese nodules, which
take up a large quantity of the sandy matrix. The concentric
character of this concretionary body is well shown towards the
exterior, and occasionally in the interior, but the general mass
is a rather light porous material with denser nests of calcitic matter
here and there. Some of the holes in the more porous parts are
suggestive of slender stems round which deposition in the first
instance has taken place, and the aspect generally may be described
as tufaceous.
(To be concluded in the May Number.)
IJJ.—Tuer Composition or Inpian LATERITE.
By H. Warrn, D.Sc. Tubingen, and F. J. Warru, B.Sc. Lond. and Birmingham.
FTER the appearance of Mr. T. H. Holland’s paper on Laterite
in the GrotocicaL MaGazinu, February number (pp. 59-69),
we can at once give the results of our analysis of Indian laterite,
without further introductory remarks. ‘They are as follows :—
I. Pure Gibbsite from Kodikanal, previously recorded in the Minera-
logical Magazine, May, 1902.
Si Og 600 640 900 alale miele 2°
TiO, 0
CA@Q coo oh ue 3A ee oy)
MiciOjnes ane Pe na Be 0
Fe, 03 “4
3 eee
PND Sewn eee WG eae EMR oer CORS
.,
HH, & F. J. Warth—On Indian Laterite. 155
Molecules of water for one molecule of alumina = 3:06, which
agrees very closely with the formula of gibbsite, A, O,4+3 H, O.
Specific gravity = 2°42.
II. Composition of four Bauaites very rich in alumina, and containing
little tron, closely resembling the variety called ‘ Wocheinite.’
2 3 4 5
Kh 12, Sr Rw
HH, O 26°47 24-00 28°10 26°94
Si Oz 93 1-79 2°01 2°39
TiO. 1°04 3°30 6°49 6°61
Ca O °36 "04 45 1155
MeO — 02 — nil
Fez Oz 4s) Ne se. 6°21 506 5°48 6°53
Ney Qs eon OAS) soo GEG cs, HDS 57°50
100°77 100:00 100°76 100°08
Molecules of water for one molecule of alumina:
WOU Boo Dsiliiles) esse YTD — oa 2°67
If we take the mean of these figures and calculate the proportion
of gibbsite and diaspore (Al,O,H,O) in the mixture, we find
72 per cent. gibbsite and 28 per cent. diaspore. As the proportions
vary from 55 per cent. to 88 per cent. gibbsite, we may roughly
say that these rich bauxites or ‘wocheinites’ consist of about
three-fourths gibbsite and one-fourth diaspore. Specific gravities :
No. 38 = 2:59; No. 5 = 2:39.
III. Composition of 8 specimens of Laterites in siti which are Bauaites.
6 7 8 9 10 11 12 13
Marwara. Mahab. Satara. Nilgiris. Nilgiris. Pulsa. Karad. Satara.
IBIBO) Sho BRE can POD) Gan WBREIS cen PAVED cag WOOO cha TS coo EES con WES
Gyre, SMOm sso SS Bog SS p00 0 NB ba Sno NO po
SOs bse | SCM See. OUR ead EB ok. BUIEE don PB ae SIO coe SEPAV ce | EHD)
TRO seen ee Smbau een Char Uipae ee aN eh ca i) cae Ore ey OK) coe TOO
Calis Se) iol 20D) cab! SEG koe ee ahs TD Gast bag LA ces OH:
MioiQ) ess ee oe tee 8 ee ee eee ntracen. sp trace ce ee20
Fe, 0, ... 18°75... 28-41 ... 26°61 ... 37°88 ... 34°37 ... 47°27 ... 51°25 ... 56-01
Alp O3 ... 54°80... 50°46 ... 48°83 ... 38°28 ... 85°38 ... 82°65 ... 30°86 ... 26°27
100:00 100:00 100°00 100:00 100:00 100:00 100-00 100-00
Molecules of water for one molecule of alumina:
DRXD gon PBB oo Sell sen BOD sso BOI cto BU con Bel ges elle!
Average of the above = 2°87, which implies 93°5 per cent.
gibbsite to 6:5 per cent. diaspore, with variation from full gibbsite
to 60 per cent. gibbsite.
These bauxites in blocks and in powder are generally red with
a shade of brown; No. 9 is light brown, Nos. 12 and 18 are of
a deep red.
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The above specimens of Indian laterite are arranged in order of
their contents of free alumina, with the exception of the first, the
pure gibbsite, which, however, is the richest in alumina if the water
is eliminated. The specimens range from 68 per cent. of free
’ alumina down to nothing. There is thus every gradation in alumina
from nearly theoretically strongest downwards, with no gap to Speak
of. If, however, we take into consideration the other constituents
we find the specimens to fall into four distinct groups.
I. By itself stands the gibbsite from Kodikanal, which is so much
free of foreign matter that in the ignited state it contains nearly
95 per cent. of aluminium oxide. As stated in the notice in the
Mineralogical Magazine, this mineral was found to form a deposit
of one foot in thickness, consisting of loose crusts or plates which
gave the impression of having been extracted from the underlying
charnockite. The sp. gr. of this gibbsite was 2°42.
We next come to specimens of the far more extensive and thick-
bedded surface deposits, which have hitherto all been classed under
the name ‘ laterite.’
Ii. Of these laterites the first four specimens belong to our second
group. They agree, as already stated, very well with those richest
bauxites which have been given the separate name ‘ wocheinite.’
They are characterized by their small amount of iron, and have even
less silica than the recorded analysis of the celebrated original
wocheinite, on an average 1°77 per cent. compared with 6:29 per
cent. at Wochein. On the other hand they contain much more
titanium - dioxide. This large proportion of titanium - dioxide
(maximum 6°61 per cent.) is very characteristic of the rich bauxites,
and a reference to the whole of the tables will show that the
titanium-dioxide gradually decreases with the free alumina until
there is only -01 per cent. left. It remains a subject for further
enquiry in what form the titanium exists when there is such a large
proportion. From the fact of its dissolving when the entire mineral
is treated with hot hydrochloric acid, and because there is always
enough iron present, we are inclined to believe that it exists chiefly
as ilmenite. As already mentioned, the specimens of this group are
mixtures of about three-fourths gibbsite and one-fourth diaspore (by
weight). The mean specific gravity of two specimens was 2°49,
which is more than that of the Kodikanal gibbsite. Our specimens
have also the characteristic pisolitic structure, the globules varying
from two to four millimetres in diameter.
III. The third group includes specimens such as geologists have
hitherto called high-level laterites. They are bauxites which have
formed from highly ferruginous igneous rocks. They belong mostly
to the area of the Deccan trap, and we find that the proportion of
ferric oxide in these bauxites is in close relation to the proportion of
iron in the trap. In the same way the small proportion of iron
in the preceding group of wocheinites indicates their origin from
less ferruginous, probably gneissic rocks. A glance at the table,
group III, also shows the regularity with which the water decreases
158 H. & F. J. Warth—On Indian Laterite.
in the same order as the alumina, whilst the iron increases
simultaneously.
Only in one case, that of No. 13, is there a slight departure from
the rule. With the exception of two specimens containing quartz-
sand, the quantity of silica is very small. Sample No. 7 contains
only 1:14 per cent. of substances other than the oxides of iron and
aluminium besides water. The ferric oxide appears to be entirely
or nearly entirely anhydrous. If this were not the case we should
obtain a regularly increasing series for the molecules of water
calculated from the total of the water for one molecule of alumina.
Although the table shows that the figures vary, there is no great
departure from the average, and, as already remarked, the mean of
all the eight specimens implies anhydrous ferric oxide and a mixture
of 93-5 per cent. gibbsite and 6:5 per cent. diaspore.
The identity of these high-level laterites with bauxite is also
proved by comparison of their composition with that of other
bauxites. Our No. 7 is almost identical with the bauxite from near
Giessen with which Dr. Max Bauer compared the specimen from
Mahé in the Seychelles.
Our specimen No. 9 comes very close to an Irish bauxite which
has been analysed by Siemens, who found the following, according
to Watts’ Dictionary of Chemistry :—
Si O2 3°5
TiO, 2-0
Fez O3 38:0
Al, O. 35:0
100-0
Treated before the blowpipe, all the specimens of group No. III
are infusible, the general character of bauxite. Only in the case of
No. 10 there were minute fused spots in small number, and No. 12
showed also traces of fusion, though they were doubtful. This
behaviour of No. 10 and No. 12 is no doubt due to these specimens
containing more silica than the others and free quartz-grains. This
infusibility serves to distinguish the pure bauxites when mixed with
Fe, O, from the low-level laterites of the following group, No. IV,
which (No. 14 excepted) fused unmistakably. Pure kaolins are
also infusible, but if the material is distinctly red from iron the test
holds good.
IV. The fourth group includes low-level laterites arranged in
order of free alumina which calculation shows them to contain.
The presence of free silica in the form of quartz is proved in
all cases, and confirms a principal character of these deposits.
Whenever distinct quartz-grains are seen in quantity, some of them
being at times rather large, we may be sure that we have a detrital
or low-level laterite. Besides the quartz-sand there is, however,
generally an even larger proportion of clay.’ This follows from the
1 On the average 30 per cent. of clay and 20 per cent. of free quartz.
HH. & F. J. Warth—On Indian Laterite. 159
proportion of combined silica which is present, and which we may
fairly assume to be a constituent of clay. In the table the amount of
clay is calculated according to the composition of pure kaolin
(kaolin equals SiO, 46-4 per cent., Al, O, 39:7 per cent., H,O
13°9 per cent.). The balance which is left after deducting both free
quartz and clay consists of free alumina and ferric oxide with water.
This is really the substance of bauxite, with gradually decreasing
proportion of alumina. The results of the analysis agree thus
remarkably well with the theory according to which the low-level
laterite is derived from the high-level laterite, and has during its
transport to a new site taken up sand and clay as impurities.
Further, the results show that the term laterite has a distinct meaning
throughout the many varieties of this rock. Laterite is bauxite
in various degrees of purity, from the richest wocheinite down to
such specimens in which the free alumina has entirely disappeazed.
In this sense the specimen from Burmah which has been analysed
by Captain James, and recorded in the Manual of the Geological
Survey of India, is also still a true laterite. Its composition is
similar to that of our two last specimens, No. 22 and No. 23. The
sample contained 30°7 per cent. quartz and 14:8 per cent. clay, and
the balance was made up almost completely of ferric oxide
(47-4 per cent.) with 4:7 per cent. water and only 1:3 per cent. free
alumina.
It cannot be said with certainty what the state of hydration of the
alumina is in these detrital laterites. They vary so much in
composition, and the colours indicate that the ferric oxide may in
some cases be anhydrous and in other cases be present as limonite.
Taking all the specimens together, the average composition is such
that there is about as much diaspore as there is gibbsite and about as
much hematite as there is limonite.
As regards the method of analysis, we found fusion with hydrogen
sodium-sulphate the best, if not the only method for all cases. By
it the free silica is readily determined as distinct from the combined
silica, the iron is obtained in solution, and so is the titanium. With
larger proportions of titanium (1 per cent. Ti O, and upwards) we
resorted to the method of separation by long-continued boiling, and
small proportions of Ti O, were determined colorimetrically by means
of hydrogen peroxide.
To carry out this work at a distance from India would have been
impossible, had we not received very liberal help in procuring
specimens from a deposit which extends over an area of thousands
of square miles. We desire to express our thanks to H.M. Secretary
of State for India, through whose kind intervention the bulk of
the very richest and most important specimens came into our
hands; also to Mr. Edgar Thurston of Madras and to Dr. D.
Hooper of Calcutta, who obtained for us the specimens by which
the true nature of the high-level laterite was proved for the
first time.
160 Reviews—Dr. Tempest Anderson— Volcanic Studies.
Jey) dst] WF IE JER OW SN
I.—Voucanic Stupies 1n Many Lanps; being reproductions of
photographs, by the Author, of above one hundred actual objects,
with explanatory notices. By Temprsr Anprrson, M.D.,
B.Sc. Lond., F.G.S., F.R.G.S., Fellow of University College,
London, Hon. Sec. Yorkshire Phil. Soc. 4to; 202 pages,
105 plates. (London: John Murray, Albemarle Street, 1903.)
HOTOGRAPHY has become, to a certain extent, the handmaid
of Science, and Geology especially is indebted to this delightful
art for many a faithful picture. The glacialists have long availed
themselves of this method of delineation, whilst the British
Association has shown its. appreciation of the value of photography
in its application to geology by the appointment of a committee to
arrange for the collection, preservation, and systematic registration
of photographs of geological interest in the United Kingdom. Since
1889, when it was first constituted, this committee has collected
several thousand photographs, many of which are of the highest
value, and a selection from these is now in course of publication.
It is not surprising, therefore, that Dr. Tempest Anderson, having
already acquired considerable skill in the art of photography, and
being, moreover, of a scientific turn of mind, should have chosen
to illustrate volcanic phenomena with the camera, as a method of
spending a physician’s holiday at once useful and agreeable.
Vulcanology was more especially selected, as it had the advantage
of giving opportunities for exercise in the open air and frequently in
districts remote and picturesque. For the last eighteen years the
author has spent the greater part of his holidays in this fashion.
During that period, Vesuvius, Htna, the Lipari Islands, Auvergne, the
Hifel, the Canaries, Iceland, British extinct voleanic regions, and
many localities on the western side of the North American continent
were visited. In delineating those phenomena he has chosen the
mechanical side of the subject, ‘‘the mode of formation of volcanic
cones and lava-streams: how the materials forming them got to
their present position, and remained there rather than elsewhere ;
how they have affected the other rocks with which they came in
contact, baking and hardening some, dissolving and removing others ;
in some cases by their superior hardness protecting the rocks over
which they have been deposited, while the surrounding parts have
been removed by denudation, so that what was once a molten stream
on the floor of a valley is now a bed of hard, perhaps columnar,
lava, capping a long hilltop, while in other cases the volcanic
beds themselves have suffered most from denudation; how veins
and intrusive sills are sometimes harder than the rocks they traverse,
and weather out into ‘Giant Walls,’ but in others are softer, and
become gullies and the beds of streams.”
The author has long been known as a demonstrator in vulcanology,
having commenced his public career before the British Association
at Aberdeen in 1885, when he read an illustrated paper on the
Volcanoes of the Auvergne. At the Bath Meeting in 1888 he read
Reviews—Dr. Tempest Anderson— Volcanic Studies. 161
a similarly illustrated paper on the Volcanoes of the Two Sicilies.
He has also been in the habit of exhibiting at the soirées of the
Royal Society, and these exhibitions were systematized into four
lectures (the Tyndall lectures) delivered at the Royal Institution.
It is scarcely to be wondered at that, with such a-record,
Dr. Anderson was appointed a member of the commission sent
out last Summer by the Royal Society to investigate the results
of the eruptions in the Windward Islands. Oddly enough, he was
on the point of bringing out the present work when this journey.
was commenced, so that the delay has enabled him to introduce
a few of his West Indian photographs.
The first seventeen plates of the work, together with their
explanatory text, are devoted to Vesuvius and its vicinity, and in
this connection the eruption of 1898 occupies an important place.
The character of these lavas is strikingly exemplified, especially
where the picture is taken at close quarters, showing a coulée of
lava of the corded type (a slaggy lava). This stream is small and
narrow, whilst some of the loose blocks around approach the cindery
or scoriaceous type of lava. For comparison there is a photograph of
blast furnace slag from Seaton Carew. Here we perceive the effects
of a tip of molten slag down a spoil-bank, thus producing a flow of
artificial corded lava marvellously like the natural product. These
two types of structure, viz. the corded (slaggy) and the cindery
(scoriaceous), are mainly dependent on the amount of aqueous
vapour, which, if excessive, renders the cooling stone vesicular, so
that a lava-stream may be slaggy in one part and cindery in another.
Next we are presented with the actual phenomena of eruption
as noticed in the middle ot September, 1898. One of these pictures
shows the moving of lava on the steep slope in the act of solidifying
as a cascade of stones, in this case of the scoriaceous type. The
picture is so graphic that we might almost fancy we heard the
rattling. ‘Then we are shown a part of the crater, as it existed
during a phase of the same eruption—a vast pit probably a quarter
of a mile in diameter, with almost vertical sides, the actual depth
being obscured by the vapours issuing therefrom: the quaquaversal
inclination of the strata of lava and tuff is well brought out.
Showers of red-hot stones were coming out of the bottom of the pit,
but the author was fortunate perhaps in not being able to photograph
any of these. Finally, we have in pl. x a picture of the explosion,
which occurred two days afterwards, as seen from the Observatory,
the magnificent cloud of vapour and ashes being intensified by the
slanting rays of the sun.
These photographs of the phenomena of eruption more especially
appeal to the vulcanologist, but there are others likewise of great
geological interest. Hver since the days of Lyell the Phlegrean
Fields have been classic ground for all those who seek to interpret
the past through the action of the present. There is probably no
more exquisite example of a crater, presumed to be extinct, than
that of Astroni (pl. xiii), whose picturesque and wooded interior
affords such a telling section of consolidated volcanic ash dipping
DECADE IV.—VOL. X.—NO. IV. ll
162 Reviews—Dr. Tempest Anderson— Volcanic Studies.
away from the centre of the cavity. As a mere artistic study this
picture is specially worthy of commendation. Well-defined extinct
craters are by no means rare in the world; there are plenty in the
Auvergne. Yet in some cases the interest is enhanced by their
enclosing a lake, such as the Pulvermaar in the Hifel or the Lac
d’Issarlés in Central France. But the queen of crater lakes is to be
found in the Cascade Range of Oregon (pl. Ixxxiii). This, again, is
a most telling picture, though the outward dip of the beds is not so
obvious, owing partly to a considerable accumulation of talus. The
dimensions are very great, as the following statement will show :—
“« An explosive eruption of enormous magnitude has removed several
thousand feet of the summit and distributed the material over the
surrounding country. The result is a crater about 8 miles by 6 in
size, the rim of which reaches a height of about 8,000 feet above the
sea. The cliffs rise about 2,000 feet above the surface of the lake,
which is in places 2,000 feet deep.” An island in this marvellous
lake shows a crater within a crater, and had this been still larger it
would have been comparable, he observes, to the Peak of Teneriffe,
which is surrounded by an old crater-ring of about the same size.
It will scarcely be necessary for us to follow the author through
the Lipari Islands and the Canaries, in both of which groups most
interesting volcanic phenomena are faithfully delineated by his
camera. But the extinct volcanic region of Central France calls for
special attention on the part of geologists, and to this region about
a dozen plates are devoted. The first of these plates (No. xxviii) is
a remarkable piece of topography, being a sort of general view of
the chain of the Puys, looking south from near the summit of the
Puy de Dome. Notwithstanding the difficulties of dealing with
such an extended landscape, the outlines are clear even to the most
distant hills, and the effective side screen of domite in the fore-
ground, besides reminding us of that peculiar rock, gives an artistic
touch to the entire composition. The companion picture, looking
north, if less artistic, is even more important from a topographical
point of view, as we almost look down into the crater of the
Puy de Pariou, while the positions of the Grand Sarcoui, the
Puy Chopine, and other noteworthy puys are indicated with great
distinctness. In the succeeding plates we are introduced to the
Puy Chopine and Grand Sarcoui at close quarters. The peculiar
elongated dome shape of the latter is well brought out, and it is
possible to believe that it was extravasated as a pasty mass in the
position it now occupies between two scoria-cones on either side of it.
Having dealt with the phenomena of the acid rocks in Central
France, Dr. Anderson presents us with some very striking pictures
of the effects of basalt in that region, and he has in many cases
selected basalt necks for illustration. In some instances these necks,
by resisting denudation, have given rise to most singular isolated
pinnacles of rock, often crowned with a building like the Rocher de
St. Michel. In this case he considers that the material forming
the pinnacle originally accumulated in a volcanic chimney as an
agglomerate ; the scoria-cone, which once probably surrounded or
Reviews—Dr. Tempest Anderson— Volcanic Studies. 163
¢rowned the whole, has been denuded away, and the more durable
rock, forming the neck, alone remains.
The delineation of columnar structure in basalt has received great
attention from Dr. Anderson, and his efforts in this connection have
been very successful. Central France, the coast of Antrim, and the
Hifel are amongst the regions which he has specially selected. Let us
take, for instance, the “ Valley of Jaujac in the Ardéche” (pl. xxxviii).
The subject has attracted the notice of many a geologist, and our
readers may remember that the ‘“ volcanic cone and basaltic lava-
current of Jaujac”’ constitutes the frontispiece of the second edition
(1858) of Scrope’s ‘‘ Volcanoes of Central France.” Our author’s
photograph deals with a limited portion of Scrope’s original picture.
Pl. xxxviii, in our opinion, serves to illustrate the character of this
work on volcanic studies, where a landscape of extreme interest and
beauty is also rendered most instructive as a geological section,
showing columnar basalt at the bend of the river. There seem
to be two beds, totalling 150 feet vertical, but the author regards
these as the result of one lava-stream, “the appearance of division
being produced by the line of junction of the columns of which
both portions are composed, and which owe their origin to cracks due
to contraction by cooling of the upper and lower surfaces respectively,
and their extension inwards until they meet.”
Whilst dealing with the subject of columnar basalt attention may
be directed to remarkable examples in the Hifel district (pls. Ixxviii,
Ixxixa, and Ixxx). The Kasekellar is a noted instance, where the
basal is massive above and sub-columnar below, breaking up into
short joints like Dutch cheeses, whence the name. Hqually remark-
able in a different way is the structure of the Hummelsberg, showing
a system of fine vertical columnar jointing, which almost reminds
one of fibrous serpentine (chrysotile) on a large scale ; whilst the
disposition of the basaltic column in the Mindenberg is held to
be an example of cooling from the top; the structure is very
peculiar. There are also two very effective pictures (small) of the
Giant’s Causeway, whilst the relations of the basalt to the Chalk
on the coast of Antrim are fully depicted and their historical
significance dealt with in the text.
There remains one very extensive subject, viz. Iceland, to which
thirty plates are devoted. To do anything like justice to this part of
the work would almost require a separate notice. Dr. Thoroddsen
has animadverted lately in very severe terms on the majority of
modern works on Iceland, as consisting largely of personal details.
Nothing of the sort can be alleged against Dr. Anderson. He
appears to have spent two Summers there, and his photographs
tell their own story of this treeless land of frost and fire, with
occasional assistance by way of interpretation in the text. It is
a triumph of the positive method as against the flood of speculation
with which geological literature is occasionally inundated.
The Hafragil’s Foss in the valley of the Jokulsa (pl. xlix) is
a fine specimen of terrace cutting through horizontal volcanics of an
older series. This river may be regarded as typical of Iceland, since
164 Reviews—Dr. Tempest Anderson— Volcanic Studies.
it rises beneath the ice-sheet of the Vatna Jokul, and after running
through the terrible waste of the Myvatn’s Orcefi, finally discharges
as a regular glacier river into the Asar Fjord on the north. In
pl. L, a more specialized section is given, where the same river
is seen plunging into a canon about 400 feet deep, cut in the
columnar basalt. The author again points out that the separate
layers observed here need not in all cases represent a different —
eruption, and he refers to his remarks on the Jaujac section
(pl. xxxviii) as applicable in this case. At the northern end of the
Jokuls4 gorge some remarkable volcanic structures are exhibited
as the result of the injection of basaltic lava into volcanic ash
(pls. lii and liii).
One other subject in connection with the copious illustration of
Icelandic phenomena must suffice—we refer to the fissures termed
Gjas, due to the unequal settlement of the lava-crusts on cooling.
These seem well developed in the Reykjanes peninsula, and are
partly due to the formation of tunnels, whereby the still liquid lava
continues to flow after the surface has consolidated. The mouth
of one of these old tunnels is shown as a lava-cava at Myvatn
(pl. Ixxii). The celebrated Almannagjé in the valley of the Oxera
is an instance of a Gja (pl. viii), and this has all the appearance
of a road hollowed out between a cliff and its undercliff. But the
most interesting series of Gjas, from an historic point of view, are
those which surround the Logberg, on which the Icelandic
Parliament met at Thingvalla. The half-plate, No. lxi, shows us
this curious rock table, held up in a fork between two faults and
almost surrounded by deep Gyjas, full of water, fresh, clean, and
running —a nice place to cool the ardour of an obstreperous
legislator !
There are many interesting photographs from well-known voleanie
regions on the west side of the North American continent; and the
author, as we have already noted, has just had time to add five very
graphic pictures of the recent West Indian eruptions. We trust,
however, that we have already indicated sufficient to give a general
idea of the work, which has been a labour of love, occupying the
author’s spare time for the last eighteen years. In this work art and
science are happily combined, so that our esthetic tastes are gratified,
whilst we are receiving instruction in the mechanism of volcanic
action, past and present. May we not say that the author and
photographer has realized the Omne tulit punctum qui miscuit utile
dulci of the Latin poet ?
Whilst expressing our admiration of this work we must draw
attention to a passage on page x of the preface, where the author
states “that the mere enumeration of books and papers on
Vesuvius and the other South Italian volcanoes occupies 340 quarto
pages of a Report of the Geologists’ Association.” Apart from the
inherent improbability of a mere list of the literature of the subject
occupying 340 quarto pages, we are in a position to state that the
present librarian of the Geologists’ Association knows nothing of any
such report. We, Eye
Reviews—Professor H. A. Miers’ Mineralogy. 165
IJ.—MiInERALOGY: AN INTRODUCTION TO THE SCIENTIFIC STuDY OF
Minerats. By Henry A. Miers, D.S8c., M.A., F.R.S., Professor
of Mineralogy in the University of Oxford. pp. xviii and 584,
with two coloured plates and 716 illustrations in the text.
(London: Macmillan & Co., 1902. Price 25s. net.) ~
ITHERTO, when asked to recommend a textbook on mineralogy,
one has been at a loss to name a book suited to the needs of
the student or serious general reader. With the appearance of
Professor Miers’ long-promised work, this difficulty vanishes, and the
book may be unhesitatingly recommended as a really readable work,
setting forth the principles of scientific mineralogy, and not unduly
burdened with facts and technical details. Most of the textbooks
hitherto attempted are little more than catalogues of the characters
(often imperfectly determined) of mineral species, and of the localities,
more or less uninteresting, where they are found. Much of this
tedious detail, only in place in larger works of reference, has
been omitted in the present book; Professor Miers has clothed the
dry bones of mineralogy and produced a work full of life and interest.
Had such an introduction to the study of mineralogy appeared years
ago, there can be little doubt but that the science would be a more
popular study than it now is in this country.
One of the most striking features of the book is its wealth of
illustration. The numerous figures, all original be it noted, are in
every way excellent; indeed, it would be possible to gain a very
good idea of the subject by simply studying the figures and the
lucid explanations with which they are accompanied. The repre-
sentation of minerals as they actually occur in nature, in addition to
idealized outline drawings of crystals, has been attempted in but
few works on mineralogy, and, as far as we know, in no English
textbook hitherto published. Many of these in the present work
have been reproduced directly from actual specimens by photographic
processes. Photographic reproduction, however, frequently fails to
bring out the relation between the planes and edges of the crystals
represented ; this difficulty has been overcome in the present work
by reproducing artistic black and white drawings of actual specimens,
the characteristic features of which are broughtinto special prominence.
The lines representing the edges of the crystals in many of these
figures might with advantage be a little less heavy, but otherwise
they are altogether excellent. In addition to the figures in the text
are two coloured plates, the one representing an interference figure
as seen in monochromatic light and the other the same figure seen
in white light. Reproduced directly by photography and three-
colour printing, these figures are probably the first of their kind to
appear in textbook illustration.
The subject-matter of the book is divided into two parts of about
the same length, each of which presents several novelties of
treatment. Part I deals with the essential properties of minerals,
and Part II consists of a description of the more important mineral
species. The first chapter of the book, treating of geometrical
crystallography, will give the beginner a clear idea of the symmetry
166 Reviews—Professor H. A. Miers’ Mineralogy.
and form of crystals; it does not pretend to be exhaustive, and
the mathematical relations, though clearly and briefly set forth, are
not brought into prominence, nor are any detailed examples given in
the methods of calculating crystals. About half (88 pages) of this
chapter is occupied by a description of the different crystal-systems ;
22 of the 82 classes are described, all those, that is to say, which are
unquestionably represented among minerals. A complete list is
given in an appendix at the end of Part I. The names employed in
Dana’s textbook for the crystal-classes (e.g., calcite class, cuprite
class, etc.) have been wisely adopted in place of the unnecessarily
long and confusing names (different in every author) which one
finds elsewhere.
In the appendix on the crystal-classes, names of the latter type
are employed, and like other authors, the present one has not
refrained from inventing new terms to denote the different types of
symmetry, some of which (e.g., alternating, equatorial, central) seem
desirable innovations. This lack of uniformity in nomenclature is
doubtless unavoidable in a science which has not been standing still,
but it is none the less much to be deprecated. In this connection
we may remark that, according to the preface, Dana’s mineral names:
have been adopted; in the text, however, are to be found fluor,
pyrites, blende, anatase, copper-glance, mispickel and other names
not used by Dana.
In the portion on geometrical crystallography there are short, but
useful, chapters on vicinal faces and light figures, and on etched
figures, the relation of which to the symmetry of the crystal is
specially pointed out. In the appendix above mentioned the
symmetry of the 32 classes is indicated by diagrams giving the
general forms of etched figures. A brief and clear account of space-
lattices is given in an appendix dealing with theories of crystal-
structure.
The optical properties of crystals are treated in almost as much
detail as the geometrical relations, and should be of value to the
student. As remarked in the preface, however, the introduction of
both Fresnel’s ellipsoid and the indicatrix may be at first somewhat
confusing. Of the remaining chapters in Part I, that dealing with
the relations between the properties of minerals may be specially
mentioned; the remarks on solid solutions, for example, are such as.
are to be found in no other general textbook of mineralogy.
In Part II, devoted to descriptive mineralogy, no attempt has been
made to give a complete list of all the perfectly or imperfectly
known mineral species. The author's aim has been rather to
give a readable and detailed description of certain minerals selected
as types, and to compare other less important species with these
types. Rare minerals are sometimes mentioned with the object of
elucidating the inter-relations of groups, but no doubtful minerals
receive mention. At the head of the description of each type-species:
is printed in smaller type an enumeration of the principal characters
of the species, an arrangement useful for purposes of reference. In
place of the usual list of localities is given a description of the mode
Reviews—Dr. Molengraaff’s Central Borneo. 167
of occurrence, associations, etc., of specimens from one or two
typical localities. Much of the tabular matter, only necessary for
purposes of reference, is collected together in appendices. The
tables of minerals arranged according to their refractive index, optic
axial angle, specific gravity, etc., will be of great use even to
working mineralogists.
Finally, the printing and arrangement of the whole book leave
nothing to be desired, while a very complete and systematic table of
contents and an equally complete and well-arranged index add
much to the value of the work. The only drawback to the book is
its high price, which we are afraid will make a wide circulation
impossible. If the costliness of the work is due to the inclusion of
the coloured plates, we are of opinion that these had been better
omitted, since they represent only one type of interference figure
and form but an incomplete series.
IlJ.—Tue Borneo Expepition.
GEoLtogicaL HxpnoraTions IN CrntTRAL Borneo, 1893-94. By
Dr. G. A. F. Motencraarr. With 89 Illustrations in the text,
56 Plates, 3 Maps, and an Atlas (folio) of 22 Geological Maps.
English Revised Edition, with an Appendix on Fossin Rapio-
LARIA of Central Borneo by Dr. G. J. Hinpr. London: Kegan
Paul & Co., Ltd., 1902. Quarto: pp. xx, 5380; Appendix, pp. 56,
pls. iv. Published by the Society for the Promotion of the
Scientific Exploration of the Dutch Colonies. Leyden, EH. J.
Brill; Amsterdam, H. Gerlings. Issued February, 1903. Price
£2 12s. 6d. net.
T is with no common interest that we have studied the fine volume
of text and illustrations, and the large folio atlas of maps which
accompanies it, prepared by Dr. Molengraaff and printed in so
admirable a manner by our Dutch neighbours (in both an English
and a Dutch edition), an undertaking which, although warmly
supported by the Dutch Colonial Government, really results from
the enterprising spirit of “the Society for the Promotion of the
Scientific Exploration of the Dutch Colonies,” and sets before our
own ‘ Royal Colonial Institute” a splendid example which they
would do well to follow.
A considerable delay has arisen in the production of this great
work owing to the fact that, soon after Dr. Molengraaff’s return
to Europe from Borneo, in January, 1895, he was appointed State
Geologist to the Transvaal; the preface to the first Dutch edition
being dated from Pretoria, October 1st, 1899; that of the English
edition from Hilversum, March 25th, 1902; but this edition,
however, was not really issued until February, 1903.
A glance at the map of Borneo conveys to the mind the idea
of vastness. It is one of the largest islands on the globe, being
next after New Guinea in extent, and only outrivalled in area
by two others, viz. Australia and Greenland, which usually rank
as continents. It lies across the equator (7° N. and 4° S.), forming
168 Reviews—Dr. Molengraafi’s Central Borneo.
one of the greatest of the Hast Indian Archipelago, and having an
area of 280,000 square miles. Visited first by the Venetian traveller
Ludovico Varthema, about 1505, it was next reached by Spain in
1521; the Portuguese followed and established a few ports in 1526,
and carried on trade with the natives for over 150 years. The
Dutch reached Borneo at the close of the sixteenth century, and
remained there for 70 years. The English followed and settled at
Bandjermassin in the south till the beginning of the eighteenth
century, when they abandoned it owing to the hostility of the
natives. The Dutch then returned, and have since 1733 slowly
increased their territory, and now hold more than two-thirds of
the whole island; but the district of Sarawak, on the west coast,
under Raja H.H. Sir C. J. Brooke, the northern part called British
North Borneo, controlled by a Chartered Company, and the native
Sultanate of Brunei, all these three (covering an area of about
84,000 square miles) are under British protection.
Borneo is a country of high mountains, heavy rainfall, tropical
forests, and big rivers everywhere; and, although known to
Europeans for nearly 400 years, its interior is still a virgin field
for the naturalist and the explorer.
Ethnologically it is a wonderful country, with a mixed population
composed mostly of Dyaks, with a large number of Malays and
Chinese. Here, on the coasts and in the estuaries and rivers, or
on the land for that matter, we have the native race, the Dyaks,
living in large communal pile-dwellings; in Brunei, for instance,
a population of nearly 7,000 may be found to-day living in dwellings
built entirely on the water, communication being only possible by boat.
In South and East Dutch Borneo the chief town is Bandjermassin on
the Riam-kina River ; here, again, most of the inhabitants are found
living either in floating raft-houses (rising and falling with the level
of the water) or in pile-dwellings. Those on the land are also
built on piles, and are often stockaded around after the manner of
the neolithic palisaded and stockaded terramare discovered in the
Po valley between Parma and Modena; while those on the water
are likewise present-day survivals of the precisely similar Swiss
and Italian pile-dwellings of prehistoric times. Thus the axiom
still holds good, ‘‘ that man under analogous circumstances acts in
an analogous manner irrespective of time and space” (F. Troyon).
The region of Dr. Molengraaff’s geological explorations is situated
principally in the north-eastern portion of the political division of
Dutch West Borneo, and forms part of Central Borneo. It is
traversed from east to west by the great river Kapoewas, which
takes its rise in the hilly districts of the extreme north-easterly
margin of the division, and in its course to the sea receives the
waters of numerous large and important tributaries, which flow to it
from the mountainous regions bordering both the north and south
sides of its basin. The total length of this river, from its source to
the sea, is stated to be 1,148 kilometres (710 miles), about 24 kilo-
metres longer than the Rhine. On the north side of the Kapoewas
basin is the mountain range known as the Upper Kapoewas, which
Reviews—Dr. Molengraaff’?s Central Borneo. 169
separates it from Sarawak, and towards the south are the Muller
mountains, the elevated Madi plateau, and the Schwaner range,
which forms the division between it and South Borneo.
The river Kapoewas forms the main highway of communication,
and from villages and stations on its banks the author obtained
native boats and helpers, with which he made the ascent of the
various tributaries as far as practicable, and when the streams no
longer served, the land-route to the mountain ranges and peaks had
to be resorted to. But in a country of tropical forest growth such
as Borneo it is next to impossible to perform any long journeys on
foot; the native Dyak footpaths through the forest—the only land
communication—are merely narrow tracks, just wide enough for
a single man ; they follow a nearly straight course, breasting steep
hills and scaling the sides of mountains without a zigzag; they are
not diverted by morasses or streams, deep gorges are simply bridged
over by trunks of trees, and the only obstacles they bend round are
lofty forest trees. As a consequence, land travel is very fatiguing
to Huropeans. Nor is the journey by boat up the streams in Borneo
without its dangers and difficulties, mainly caused by the frequent
waterfalls and rapids, where ledges of hard rock cross the river bed
and necessitate unloading and a portage; the streams, moreover,
are liable to sudden and dangerous spates.
Dr. Molengraaff found that the lines of dislocation of the rocks in
the Upper Kapoewas territory followed a generally east and west
trend, and this led him to infer that by taking a route from north to
south a continuous geological section from the boundary of Sarawak
on the north, right across Dutch Borneo to the Java Sea, might be
observed. This course was adopted on his return journey, and,
starting from Boenoet on the Kapoewas, he travelled southward,
crossed the Madi plateau, and, reaching the Schwaner range, made
the ascent of Mount Raja. one of the highest peaks (2,278 metres).
At Mount Boenjau the water-parting between West and South
Borneo was crossed, and descending the Menjoekoei river to its
junction with the Samba river, and thence by the great river
Katingan, he reached Pegattan, close to the coast, on the
28th October, 1894, and four days afterwards arrived at Bandjer-
massin by sea. The journey down-stream of 3800 miles (not
counting river curves) was accomplished in a fortnight. The
territory traversed by this southern route was absolutely unexplored
scientifically, and the greater part of it had not previously been
reached by any Huropean, so that the physical and geological
descriptions of it given by Dr. Molengraaff in chapters x, and xi,
are of the greatest interest.
The principal end of the expedition, to ascertain the nature and
the relative succession of the rocks of Central Borneo, which may
be said to be the core of the island, has been successfully carried
out by the author, and from his observations we obtain for the first
time a satisfactory outline sketch of its geological features. The
oldest rocks recognized are strongly folded, amphibolite and chlorite
schists and quartzitic slates occurring in the hilly country near
170 Reviews—Dr. Molengraaff’s Central Borneo.
Sémitau and other localities. Petrographically they are similar to:
crystalline schists of Archean age, but it is possible that they are
only sediments altered by granite intrusions.
Next, above the doubtful schists, there is a great thickness of
phyllitic clay-slate with a silky lustre, alternating with beds of
sandstone, greywacke, and quartzite. The strata are 3 nearly vertical.
No fossils have been found, and its age is therefore unknown, though
very possibly it is Paleozoic. It has been named the “Old Slate
Formation.” ‘The Upper Kapoewas range, a typical mountain chain
much worn down by erosion, which runs nearly east and west and
forms the boundary between West Borneo and Sarawak, and between.
West and Hast Borneo for a distance of 225 kilometres, is mainly
built up of these slaty strata. On the south side of the range the
beds are abruptly cut off by a great fault.
The next younger formation, known as the ‘‘ Danau Formation,” is
composed of highly tilted and contorted beds of chert, jasper, and
hornstone, quartzite, clay-slate, sandstone, diabase, diabase-tuff, and
porphyrite, which have been brought down to the level of the “‘ Old
Slate Formation” by a fault. The beds have an east and west
strike, and they have been traced from the Lake district for a distance
of 280 kilometres, quite into Hast Borneo. The chert, jasper, and
hornstone beds are of organic origin, and are mainly composed of
Radiolaria. In the Upper Kapoewas region their thickness is
estimated at 100 metres, and they are regarded by the author as deep-
sea deposits. The beds of diabase and diabase-tuff, which alternate
with the chert and hornstone, are attributed to submarine and
volcanic eruptions. Some of the tuff beds likewise contain Radiolaria.
This formation is of pre-Cretaceous age, and the Radiolarian beds are
probably Jurassic.
A system of moderately tilted and folded beds of marly and sandy
deposits succeeds the Danau formation. Along the river Seberoewang
the marls contain Orbitolina concava, which indicates that they are of
Cenomanian (Upper Greensand) age. The deposits were probably
laid down near a coast, and a portion of Central Borneo must then
have been dry land. The rocks occur in various localities, and extend
to the south of the Madi plateau.
The oldest Tertiary deposits in Central Borneo have not been met
with in sit%; they are only known from boulders of grit, containing
Nummulites and Orbitoides, which occur in the valleys of the rivers.
Embaloeh and Tekelan ; they may be regarded as of Oligocene age..
An enormous area is covered by a ‘formation named the Old
Tertiary or Mélawi Group, which consists of horizontal beds of sand-
stone, quartzitic sandstone, and claystone, with intercalated seams of
coal. Molluscan shells occur in these beds in places ; according to
Krause and Martin they are brackish-water forms, which probably
lived in estuaries. At the time of their deposition the whole of
Central Borneo, with the exception of the Upper Kapoewas range,
was submerged beneath the sea. The greater part of the Madi
plateau and the Schwaner range, which separates West from South
Borneo, are formed of these rocks.
Reviews— Dr. Molengraaff’s Central Borneo. 171
The coal-seams in these Tertiary beds appear to be formed of
plant débris and trees brought down by the river floods, and not of
slowly formed vegetable growths in siti, as is the case with most
Paleeozoic coal-seams. As a rule, the Borneo coal is too much mixed
up with sand and clay to be of economic value, but the author records
several localities where the beds are of sufficient purity and thickness
to be worth prospecting for mining purposes. They are shown on
the north shore of the Kenepai river (p. 38) ; on the Mondai river
(p- 60; also Atlas, Map 6, sect. F & H); below Karangan Pandjang
(p. 278) ; on the Sékilit, a tributary of the Tébaoeng, several layers.
of fairly good but somewhat fissile coal were exposed (profile B,
Map ixa, pp. 288 and 293) ; and again on the Pinoh river, where
a bed of coal of inferior quality rests on claystone beds with
concretions and numerous shells (see section p. 142, fig. 30).
Succeeding the Old Tertiary Sandstone formation, there are
extensive deposits of fluviatile and lacustrine origin, consisting of
beds of fine sand and mud mingled with vegetable débris, which are
regarded as probably of Quaternary age; but in Borneo there is such
a close resemblance in the sandstones and clays of different ages that
in the absence of fossils it is almost impossible to determine between
those of Tertiary, Quaternary, and recent dates.
Owing to the heavy tropical rainfall, the denudation of the higher
land-areas in Borneo is on an enormous scale, and the gravels, sands,
and finer materials brought down by the rivers are spread over
extensive areas. Thus in West Borneo, which has a total area of
145,000 square kilometres, it is estimated that 50,000, or nearly
one-fifth, are covered deeply with alluvial deposits.
Between the hills and the flat alluvial grounds of most of the
large rivers, there are older fluviatile deposits of a gravelly character,
which generally contain gold. The gold is obtained by Chinese,
who work the beds in a very primitive manner. They are very
reticent respecting the results of their operations, which are probably
not over remuuerative, but if hydraulic machinery were employed
the chances of success would be greater.
All the later changes in Borneo appear to be due to atmospheric
influences, which have greatly diminished the height of the island,
and at the same time enlarged its circumference by the rapid
deposition of the alluvial material brought down by the rivers.
The finer materials are carried far out to sea, and, from the dis-
coloration of the water round the coasts, Borneo has received its
name of “ Mudland.”
Intrusive and eruptive rocks are largely developed in Central
and South Borneo. Granite areas occur in the Schwaner mountains,
the base of which principally consists of this rock, and in the
bordering hilly districts of South Borneo; also in the Sémitau Hills,
the Boengan Hills, and the lake district. It is mainly an amphibole-
biotite-granite with plagioclase, which frequently passes into tonalite.
Its intrusive character is proved by the intense alteration of the
surrounding rocks near the zone of contact.
Diorite, gabbro, norite, peridotite, serpentine, and diabase have
been met with in different districts.
172 Reviews—Dr. Molengraaff’s Central Borneo.
There are three principal volcanic areas in Central Borneo, the
Muiler mountains, the northern slope of the Schwaner mountains,
and on the Samba river. The most important is the Muller range,
forming the south boundary of the Upper Kapoewas plain; its
known extent in an east and west direction is 280 kilometres, and
its average breadth about 45 kilometres. The whole of the range
consists of volcanic rocks; those of the western portion are of
a decidedly andesitic character, and those of the eastern of rhyolitic
and dacite types. Thick beds of tuff are also present in which there
are large quantities of silicified wood, partly stems of trees still in
an upright position. The average height of the mountain peaks,
which are mere fragments of a former unbroken tuff-plateau, is
about 1,100 metres. The volcanic action which produced these
mountains is believed to have commenced during or shortly after
the Cretaceous age, and, after continuing through the Tertiary,
terminated probably about the commencement of the Quaternary
period.
In an appendix, Dr. G. J. Hinde gives a description of the
Radiolaria which form a large part of the chert, hornstone, and
jasper series of rocks, and are present also in the alternating beds
of diabase-tuffs, marls, etc., belonging to the Danau formation,
mentioned above. The unexpected discovery of these siliceous
organic rocks in Central Borneo by Dr. Molengraaff is of considerable
interest in view of the fact that within the last few years rocks
of a similar character have been found in other parts of the Hast
Indian Archipelago, at Celebes and Billiton, and also in various
parts of Hurope, in California, Australia, and Japan.
About one hundred different forms of Radiolaria were recognized
and described in thin sections of these Central Borneo rocks, and
figures of them, carefully drawn by Mr. A. T. Hollick, are given
on the accompanying Plates. Of these forms, seventeen occur in
the rocks of other countries, and eighty-three are at present only
known to Borneo. They show many points of resemblance to the
Radiolaria present in rocks of Jurassic age in Switzerland and Italy,
and to those of approximately the same age in the coast ranges of
California, and it is highly probable that the deposits in Central
Borneo in which they occur are likewise of Jurassic age.
In concluding our notice of this most interesting and valuable
work, we wish particularly to call attention to the series of maps,
charts, and sections in the atlas, and to the striking photographs,
illustrating the natural scenery and geological structure of the
country, and giving lively reproductions of the people, their homes,
both for the living and the dead, and the strangely carved figures
and memorial poles which surround their settlements. In the
charts of the rivers the salient geographical and geological features
of every portion of their course are carefully noted, and the geo-
logically coloured maps and sections enable the reader readily to
follow the observations recorded in the text.
The author acknowledges his obligations to Messrs. Schlumberger
and R. Bullen Newton for determining the Nummulites ; to Dr. Krause
Reviews—A New Rock-Classification. 173:
and Professor Martin for examining the shells ; and to Dr. Schroeder
van der Kolk for assisting in the microscopic study of the rocks.
In the preface to the English edition Dr. Molengraaff specially
thanks Dr. G. J. Hinde for reading the proofs and revises, and to
this supervision may perhaps be attributed the general absence of
errors in the text, which are usually too prominent in translations
printed abroad. A separate vocabulary of Dyak names of places
and things (most of which are given in notes or in the text and index,
but noé collectively) would have proved of service to English readers.
We commend the work to all who are interested in the geology
of the Hast Indies, and hope it will find a place in all the public
reference libraries in Britain and America and the Colonies.
IV.—A New Rocx-CuasstiFIcaTion.
QUANTITATIVE CLASSIFICATION OF IGNEOUS Rocks, BASED oN
CHEMICAL AND MINERALOGICAL CHARACTERS, WITH A SySTEMATIC
Nomencnature. By Wurman Cross, Josrrn P. Ippinas,
Louis V. Prrsson, Henry S. Wasuineton. S8vo; pp. 286.
(Chicago, 1903.)
HE classification of the igneous rocks is a question which has
engaged the attention of many petrologists; and, as a wide
divergence of opinion sufficiently attests, it involves problems of
much difficulty. The memoir before us is the joint production
of four well-known American authorities, and represents, we are
told, an exhaustive discussion of the subject extending over many
years. Moreover, it is not merely a contribution to a vexed question,
but aims at affecting a final settlement of it. For these reasons the
scheme put forward, and the arguments upon which it is based,
demand a frank and careful consideration.
Our authors start from the proposition, which will scarcely be
disputed, that existing methods of classification are illogical and
in many respects unsatisfactory. But we are by no means convinced
that they have correctly diagnosed the imperfections of the schemes
in present use; and on such diagnosis the success of any proposed
remedy must necessarily depend. The confusion which prevails in
the classification of igneous rocks is in some measure due to causes
inherent in the nature of the subject-matter, and especially to the
absence of any well-defined ‘species,’ such as constitute the units of
classification in the sister sciences. But the present difficulty is, as
it appears to us, attributable in a much greater degree to the rapid
and unequal growth of the science of petrology. Fifty years ago
the classification of igneous rocks was of the crudest kind, but it
seems to have been quite adequate to the state of knowledge at that
time. The great revival of petrographical research which followed
the introduction of microscopical methods has instigated a large
body of workers, and the annual output, especially from the German
laboratories, has attained a very considerable volume. The great
bulk of this work is of a purely descriptive kind—petrography in
174 Reviews—A New Rock- Classification.
the strict sense. Much of it is doubtless of great value; but its
value can be only very partially realised, for the reason that this
accumulation of material has far outstripped the other side of the
science, the business of which is to co-ordinate the scattered
observations and bring to light the principles which underlie them.
The pearls are there, but there is no thread on which we can string
them. During recent years, however, we have witnessed many
indications of a reaction from this state of things. From various
quarters memoirs have been put forth in which very broad views
are taken of the groups of rocks dealt with, the question of their
mode of origin being kept constantly in sight. We may remark in
passing that American petrologists, including some whose names
appear at the head of this article, have taken their part in the
advance on these lines. Much stress is now made on the essential
mutual relationships of associated rock-types, and Brogger has gone
so far as to give a provisional genealogical tree for those of the area
which he has made his own. Such essays in the direction of
a comprehensive genetic treatment are necessarily tentative, but
we have no sympathy with those who would dismiss them as mere
‘speculation. Their influence is already very apparent. Petrologists
feel that they have almost within grasp a fundamental principle
analogous to that of descent, which lies at the root of classification in
the organic world; and this warrants a confident hope that there
may emerge in due time a truly natural classification of igneous
rocks. If the expectant attitude of mind here suggested is, as we
think, very general, the appearance of an elaborate artificial scheme
at the present juncture will seem to many a step in the wrong
direction.
The standpoint of the authors is clearly defined in one of their
prefatory remarks: ‘(The present systems are to a certain extent
founded on theory or hypothesis, while classification in order to be
stable must eschew all such bases, and be founded only on ascertained
facts.”
As interpreted by what follows, the stability here made a
desideratum must be understood as rigidity; for the argument
leads to the setting up of an unyielding framework, in which,
between the arbitrary partitions, each rock, whether discovered or
undiscovered, may find its appropriate pigeonhole. Although we
are under the disadvantage of having no alternative scheme to offer,
we venture to submit that an elastic classification, embodying what
is known and capable of being adapted to the requirements of
increased knowledge, might with equal propriety be described as
founded on ascertained facts. At least, it may be pleaded with some
reason that existing systems fail, not because they involve a certain
element of hypothesis, but in some measure because their implied
hypotheses are fallacious.
Some criticism on general grounds we have thought admissible ;
but the scheme before us is professedly empirical, and we cannot do
justice to it without adopting for the purpose the same point of
view. The first impression of complexity, due partly to the strange
Reviews—A New Rock- Classification. 175
terminology introduced, is not a just one. The principles upon
which the whole assemblage of igneous rocks is divided and sub-
divided are, at least on the face of things, perfectly simple, and they
are carried out logically and consistently throughout. The criteria
appealed to are, moreover, of a strictly quantitative kind, so that all
ambiguity and compromise are excluded, manifestly an advantage if
our object is to provide each rock with a precise systematic position
and name. It follows, of course, since the hard dividing lines have
no counterpart in nature, that rocks having the closest affinities
must sometimes be divorced; but this is a drawback incident to any
arbitrary scheme.
The basis of classification is mineralogical composition, though
this rough statement needs, as we shall see, important qualification.
The mineralogical criteria selected are such as correspond with more
or less important differences among the rocks themselves, and those
which are deemed of most importance are used in making the major
divisions of the scheme, the principle being carried out, as it seems
to us, with skill and judgment. ‘Thus the rock-forming minerals
are first grouped under two heads, the siliceous and aluminous on
the one hand and the ferro-magnesian on the other, or, as we
may conveniently say, the light and the dark. The whole of the
igneous rocks are then divided into five great classes, according
to the ratio which the total light minerals bear to the total dark :—
(i) Light minerals extremely abundant; ratio greater than 7 : 1.
(ii) Light minerals dominant; ratio between 7: 1 and 5: 3.
(iii) Light and dark minerals nearly equal; ratio between 5: 3
and 3: 5.
(iv) Dark minerals dominant; ratio between 3: 5 and 1: 7.
(v) Dark minerals extremely abundant; ratio less than 1 : 7.
This we may regard as in some sense an extension of Brégger’s
leucocratic and melanocratic groups. In the first three classes
subdivisions are made with reference to the nature of the white
minerals, five subclasses being defined in each class according to the
ratio of quartz, felspars, and felspathoids on the one hand to
corundum and zircon on the other. In the last two classes,
where dark minerals preponderate, these are made the basis of a like
subdivision, the critical ratio adopted being that of pyroxenes,
olivine, and magnetite to apatite, etc. This produces an ill-balanced
arrangement, for it is evident that in every class the first subclass
must greatly outweigh all the others. It is, however, easier to
criticise the scheme in these particulars than to improve it. It is
not possible here to follow out all the details of this ingenious
arrangement, and we will only note how the subclasses are divided
into orders. In the first three classes this is effected with reference
to the preponderance of quartz, felspars, or felspathoids among the
white minerals. Since quartz and the felspathoids are ‘ antithetical,’
not being found in company in igneous rocks, it is possible here to
use at once the ratios of quartz to felspars and felspars to felspathoids ;
which leads to nine orders in each subclass, the dividing ratios being
176 Reviews—A New Rock- Classification.
the same as before. In classes iv and v each subclass is divided
into five orders, according to the ratio of pyroxenes and olivine to
iron-ores. By further particularisation of the constituent minerals
the authors establish successively suborders, rangs, subrangs, grads,
and subgrads. The reason given for the spellings ‘rang’ and
‘grad’ is that ‘rank’ and ‘grade’ are so frequently employed in
a general sense, but this consideration will not console French and
German readers. For our part, we are loth to see the words
‘class’ and ‘order’ tied up to special meanings, and should have
preferred to borrow such terms as ‘domain’ and ‘nome’ from the
vocabulary of the older systematists.
This leads us to notice that the new classification is expressed
throughout in terms of a new nomenclature. Given the one, we
must indeed grant the necessity for the other. As the authors justly
remark, petrology has suffered sufficiently from the redefining of
terms, a license which would not be patiently conceded in any other
branch of science. It is, moreover, a part of their design that each
term shall carry its own precise meaning on its face. To this
end they have boldly thrown aside the Greek lexicon, and con-
structed new words, each of which is a frank barbarism, but conveys
an explicit meaning on a certain mnemonical plan. Thus the two
groups of minerals, which we have distinguished above as the light
and the dark, are designated by what the late Lewis Carroll called
‘ portmanteau-words’; salic, recalling s-ilica and al-umina, and femic,
suggesting ferro-magnesian. The five classes of rocks are named
persalic, dosalic, salfemic, dofemic, and perfemic. A like method is
pursued through all the minor divisions. In spite of its obvious
utility, it has at first a decidedly irritating effect, and will not
improbably prejudice the reception of the scheme. These uncouth
classificatory terms, however, need not be often used in speaking
of the rocks themselves, for each subdivision inferior to subclass
is provided with a proper name derived from some country or
locality where the rocks are typically exhibited. We have thus, for
a granodiorite from the Yosemite, the order Britannare, rang
Toscanase, subrang Toscanose. Different terminations are used to
mark divisions of different magnitude or status, a feature which, we
think, must be commended. The termination -ite is at present
greatly overworked, and a novice might plausibly suppose lherzolite
to be something of equal importance with granite.
The only serious criticism that we have to make upon the new
classification, regarded asa purely empirical scheme, remains to be
noticed. The percentage mineralogical composition which is the
basis of classification is an ideal one, which may or may not agree
with the actual composition, and in some cases departs widely from
it. Thus the leucitite of Capo di Bove is assumed, for the purpose
of fixing its systematic position, to contain about 11 per cent. of
anorthite and 9 per cent. each of olivine and akermanite, although
none of these minerals is actually present in the rock. Some of the
actual constituents, melilite and biotite, are discarded, because their
complex formule make them unsuitable to be included in the list of
Reviews—A New Rock- Classification. 177
‘standard’ minerals recognized in the scheme. The authors would
justify this treatment, “not only by the fact of the variable
possibilities of crystallization in one magma, but because of the
difficulty of determining the quantity and chemical character of the
minerals actually present in many rocks. It is further warranted
because of the impossibility of determining the minerals in a great
number of rocks in which they are too small, and because of the
incomplete crystallization of all more or less glassy rocks.”
It seems to us that artificiality is here pushed to the extreme limit,
and an element of complexity, very burdensome in practice, is dragged
in. Rules of an elaborate kind, though presumably sufficiently
definite, are given for calculating the ideal mineral composition or
‘norm ’ from the chemical analysis of the rock. Further, we are told
that a knowledge of the actual mineral constituents and their true
percentages, even when they are all ‘standard’ minerals, is not
sufficient ; we must calculate from this to the chemical composition,
and thence back to the norm. he norm is thus merely a circuitous
device for presenting the chemical composition, and we are tempted
to ask why the latter was not taken directly as the basis of classi-
fication. A scheme beginning with five classes defined by silica-
percentage, and proceeding to minor divisions with respect to the
other chemical constituents, would seem to offer the advantages
without the drawbacks of the scheme before us. It must at least be
recognized that the quantitative precision which is the characteristic
of this system recoils upon its inventors, since a like minute accuracy
is requisite in the diagnosis of every rock-specimen. We question
whether a given rock could ever be referred with complete confidence
to its place in this scheme in the absence of a trustworthy bulk-
analysis, and even this might fail unless a perfectly fresh specimen
were forthcoming.
It is impossible in the space at our disposal to present a complete
account of the scheme with all its ingeniously contrived details. If
we have in any respect misapprehended its scope, we must plead the
complete novelty of the system and its elaborate aspect upon a first
view. Assuredly we have not approached it in any unfriendly spirit,
saving only the predilection we have avowed for a more natural
treatment, or, in other words, our desire to see the Gordian knot
untied and not cut. There remains the consideration that the success
of what purports to be a practical scheme depends ultimately upon
its innate power of commending itself to practical workers. We
learn that the new classification has already. gained adherents in
America, but we doubt whether it will find favour, eg., in the
German Universities, from which so large a proportion of our
petrographical work emanates. It suggests, partly perhaps by its
quaint nomenclature, a comparison with Volaptik and Esperanto.
Now there is something in human nature which ordains that
languages shall grow, and not be produced ready-made; and, whether
we call this stubborn conservatism or an instinctive grasp of the
evolution philosophy, it insinuates a foreboding for the scheme before
us, no less than for its terminology.
DECADE Iy.—YOL. X.—NO. Iv. 12
178 Reviews—A New Rock- Classification.
‘Our criticism, so far of a merely destructive kind, will be made
‘more intelligible if we may be allowed to indicate roughly the lines
‘on which, as we think, a real advance may be looked for. Instead
of beginning at the top and dividing down, we would begin at the
bottom and build up. The unit of classification would be the
sufficiently definite entity usually spoken of as a rock-type. The
necessity for a given type being once established, and the characters
of the type clearly defined, it should receive a name, preferably
derived, as is customary, from the type-locality ; and thereafter any
attempt to alter the definition, or to extend the name beyond it,
should be firmly resisted. If this proviso could be secured, the
often-heard objection to the multiplication of names would become
merely an objection to the increase of knowledge. Concurrently
with the settlement of known types and the investigation of new
ones, we should expect to gain a clearer insight into their mutual
relations from the genetic point of view, and the information thus
acquired, in the field as well as in the laboratory, would enable
us in due time to group the types into a natural system expressing
our knowledge of their chemical, geological, and geographical
relationships. In such a system there would be no finality ; indeed,
its changes would be in some degree a measure of the progress of
petrological science. The conception is one far removed from that
embodied in the scheme now before us. It is true that a natural and
an artificial system might conceivably exist side by side, each being
employed for its appropriate purposes. Such a dual classification is
evidently contemplated by the authors, when, for instance, they
expressly leave the terms ‘family’ and ‘series’ free for use in
a petrogenetic connection. It is easy to see, however, that the case
of petrology differs in fundamental respects from that of botany,
and we cannot doubt that the general adoption of a fixed empirical
scheme would greatly hinder the development of a natural classi-
fication at some future time. Whether the present bold proposal
meets in a convenient manner the immediate requirements of
petrography is a different question, and one which will find its true
aswer in the reception accorded to the scheme by the general body
of workers.
In conclusion, we may state that the exposition of the system
by its inventors leaves nothing to be desired in respect of lucidity
and precision. It is reprinted, together with an admirable historical
survey of rock-classification by Dr. Whitman Cross, from the Journal
of Geology. The volume contains certain additions, including
a useful glossary, which inspires the reflection that compositors
and proof-readers will not be among those who welcome the new
terminology. The book seems, however, to be carefully corrected,
and is brought out in a form which fully maintains the reputation of
the University of Chicago Press.
ACE.
Reports and Proceedings—Geological Society of London. 179
I= SIDS) VE S| 2 INTID) JesVO OAs iNierSe
GroxnogrcaL Socrrety or Lonpon.
Y.—February 20th, 1903.—Professor Charles Lapworth, LL.D.,
F.R.S., President, in the Chair.
ANNUAL GENERAL Meetine.
The reports of the Council and of the Library and Museum
Committee for the year 1902, proofs of which had been previously
distributed to the Fellows, were read. After premising that the
Society continues to be generally in a flourishing condition, the
Council stated that the number of Fellows had undergone but little
change in 1902. The number elected was 48 (4 less than in 1901),
of whom 380 qualified before the end of the year, making, with
18 previously elected Fellows, a total accession of 48 in the
course of the twelve months under review. During the same period,
the losses by death, resignation, and removal amounted to 41,
the actual increase in the number of Fellows being therefore 7
(as compared with a decrease of 4 in 1901). The total number
of Fellows on December 31st, 1902, was 1,258.
The balance-sheet for that year showed receipts to the amount of
£3,439 16s. 3d. (including a balance of £403 12s. 3d. brought
forward from the previous year), and an expenditure of
£3,125 8s. Td. (exclusive of the sum of £250 invested in Natal
Government 3 per cent. stock).
The issue of the Catalogue of Type and other important
Specimens in the Society’s Museum, based on Mr. Sherborn’s
manuscript catalogue, edited and prepared for publication by the
Rev. J. F. Blake (to whom the Society are greatly indebted), was
also announced.
The reports having been received, the President handed the
Wollaston Medal, awarded to Professor Heinrich Rosenbusch,
For. Memb.G.8., of Heidelberg, to Professor W. J. Sollas, M.A.,
D.Se., F.R.8., for transmission to the recipient, addressing him as
follows :—Professor Sollas,—
No man has exercised a greater influence on the progress of petrological science
than Professor Rosenbusch. Though a master of detail, he has always insisted on
the important bearing of microscopical studies on many of the great theoretical
problems of modern geology.
In his celebrated researches on the Steigen Schiefer he combined stratigraphical,
mineralogical, and chemical data in such a manner that his memoir must for all time
remain a classic in geological literature. His subsequent work is all of the same
philosophical character, and every question that he has handled has been fundamentally
modified and notably advanced as the result of his investigations. The fertility
which he has shown, in the production of new and often protound theories, has only
been equalled by the courage with which he has discarded the old so soon as they
have proved unsatisfactory or incomplete.
The successive editions of his great work on the microscopic characters of minerals
and rocks have been landmarks in the progress of the science. The range of his
knowledge therein revealed is enormous, yet we never feel that his writings are
overburdened with detail, because of the power of philosophical generalization with
which he marshals his facts, and reduces the whole to a consistent and well co-
ordinated unity.
180 Reports and Proceedings—Geological Society of London.
As a teacher Professor Rosenbusch has especially excelled, and the devotion and
enthusiasm both of himself and his pupils have greatly helped to awaken the interest
of geologists in petrological investigations, and to give to these investigations the
prominent position that they now occupy.
The Council of the Geological Society make the award of their Wollaston Medal.
to Professor Rosenbusch in grateful appreciation of these pre-eminent services to
geological science.
Professor Sollas, in reply, read the following letter which had
been forwarded by the recipient :—Mr. President,—
‘¢ Although the Geological Society, for many years past, has accustomed me to
a most benevolent judgment of my scientific work, I feel greatly surprised by the
award of the Wollaston Medal, the highest honour which the Council of this illus--
trious Society can bestow. I beg to offer my cordial thanks for this distinction,
which I thought far beyond the limits of my aspirations.
‘«T may proudly contess to have passed a life of earnest and unceasing endeavour
in the attempt to understand and to decipher those grand and mysterious documents,
wherein the geological history of our mother Earth has been written down by Nature:
itself; but I am fully aware of the insignificance of the results obtained. Every
word which it is our good fortune to decipher involves a new riddle, and so I daily |
repeat the first scientific experience of my infancy—that the art of spelling is a most
difficult one.
<‘There are many members in this illustrious corporation to whom I owe a vast
debt of scientific information and of personal encouragement. The high honour
received at their hands on this day will be a stimulus to me for ever-renewed attempts.
to proceed on my onward way, ynpdokw Saiel roAAd SidacKdmevos. It will be,
indeed, a great satisfaction to me, if the rest of my lite’s work prove not unworthy
of the approbation of this ancient and renowned Society.”’
The President then presented the Murchison Medal to Dr. Charles
Callaway, M.A., addressing him in the following words :—
Dr. Callaway,—
Your work among the ancient rocks of Shropshire—Murchison’s classical county—
commenced as early as 1874, when you brought before this Society evidences of the
occurrence of Tremadoc fossils in the so-called ‘ Bala’ rocks of that area; but your
conclusions were then in advance of the times. In your second paper, published in
1878, on a ‘‘ New Area of Cambrian Rocks in Shropshire,’’? however, you not only
demonstrated by means of the abundance of fossils the accuracy of those conclusions,
but you made that paper the starting-point of what, as afterwards carried out by
yourself and others, has effected almost a revolution in our previous knowledge of
much of the older half of Shropshire geology.
You first suggested in that paper the Archean age of the Wrekin volcanic series,
and in several subsequent papers you not only showed the extension of these voleanic
and Cambrian rocks into the Caradoe area and elsewhere, but introduced into the
geological literature of our older rock-groups the names Uriconian, Longmyndian,
and Malvernian.
Your researches also in the Malvern Hills, in Anglesey, and in the complicated
Assynt and other regions of the North-Western Highlands were all of them most
fruitful in discovery, and stimulated the work of others in no ordinary degree. And
ot your later researches into the obscure phenomena of the crystalline and metamorphic
rocks, much the same may be said. As one of those who have followed your track
to their great comfort and benefit, and as one who has for more than thirty years
been honoured by your friendship, it is a great pleasure to me to be permitted to hand.
you this Medal on behalf of the Council of the Geological Society.
Dr. Callaway replied as follows :—Mr. President,—
I am deeply sensible of the honour conferred upon me by the award ot this Medal.
It is to me a special gratification that it bears the name of Murchison, tor the greater
part of my work has been on ground rendered classic by his genius. We honour him
as one of the chiet of those who laid the foundations of our knowledge of the oldest
rocks, and I am proud to haye been able to add a few stones to the superstructure..
That I receive this distinction at your hands is a peculiar pleasure. You also have
Reports and Proceedings—Geological Society of London. 181
laboured long in the field of Archeean and Proterozoic geology. Your kind and
‘generous appreciation has, therefore, a personal as well as an official value.
In presenting the Lyell Medal to Mr. Frederick William Rudler,
late Curator of the Museum of Practical Geology, Jermyn Street,
the President addressed him as follows :—Mr. Rudler,—
Our science demands for its progress not only men who discover new facts, but also
men who will explain and illustrate its facts and theories to those who are anxious
to understand and to make use of them. There are few among those who have been
both learners and workers in the science during the last thirty years who do not retain
grateful memories of the instruction and assistance which at one time or another you
have personally afforded them.
Further, ow: science needs for its appreciation by the economic world and the
public those who, being familiar with the facts already gathered together, will
present them in a clear and convincing form, and expound their practical applications.
In this respect also you have done our science lasting service. Indeed, your long
official career at the Museum of Practical Geology has been a record of wuselfish
devotion to the advancement ot the practical and educational sides of geology.
In countless ways—in reviews, in the later editions of Ure’s famous ‘‘ Dictionary
of Arts, Manufactures, and Mines’’; in your masterly essays on ‘‘ Experimental
‘Geology,’’ and on ‘ Fifty Years’ Progress in British Geology,’’ delivered as
Presidential Addresses betore the Geologists’ Association—not to mention anthropo-
logical and other addresses,—you have given evidence of your wide knowledge of
the literature and substance of geology and the allied sciences, of your sound
judgment, and of your exceptional capacity for transmitting to others the accurate
knowledge which you possess.
It affords, therefore, to the Council of the Geological Society the greatest satisfaction
to award to you the Lyell Medal, which, according to the words of its founder, is to
be given to one who ‘‘has deserved well of the science.”’
Mr. Rudler replied in the following words :—Mr. President,—
To have the privilege of standing here as the recipient of a Medal is a far higher
honour than I had ever dared to expect. While acknowledging most gratefully,
though I feel most inadequately, the generous action of the Council in making this
award, I am also anxious to express my deep sense of indebtedness to you, Sir, for
the very indulgent words with which you have been so good as to enrich this
presentation. If anything like personal detachment from such an award were
permissible, I should like to be allowed to regard this as a token of sympathy between
this Society and the institution with which I was so long connected, and where the
ruling desire of every officer is—if I may use the words of the illustrious founder of
this bequest, which you have just quoted—to deserve well of geological science.
It is, Sir, a matter of extreme gratification to me that I should find myself unexpectedly
honoured by the possession of a Medal founded by our great master, whom it was
my privilege to know personally, and whose memory I so profoundly revere.
The President then presented the Bigsby Medal to Dr. Henry M.
Ami, M.A., of the Canadian Geological Survey, addressing him as
follows :—Dr. Ami,—
The members of the Geological Society who interest themselves in the Paleozoic
formations of Britain and America, are well aware of the extent and importance
of your work among the Paleozoic rocks and fossils of Canada. As Assistant-
Palontologist to the Canadian Survey, you have not only been for many years
responsible for much of the classification and tabulation of the Lower Palaeozoic
fossils in the Museum of that Survey, but you have visited the places where they were
collected in the field, and identified on the spot their local horizons. This two-sided
knowledge has enabled you in several of your papers, such as those bearing on the
“«Geology of Quebec and its Neighbourhood,’’ the ‘‘ Utica Terrane,’’ and the
“Organic Remains and Geological Formations of the Eastern Townships,”’ to throw
much leht on disputed questions of succession and stratigraphy.
Nor has your work been restricted to the older Paleozoic rocks. Your papers on
the ‘* Knoydart Formation of Nova Scotia,’’ the ‘‘ Carboniferous Formations of
e
182 Reports and Proceedings—Geological Society of London.
Canada,”’ etc., have done much to clear up the difficulties of the correlation of these
formations with those of other countries. Neither must we forget the many papers:
in which you, with fulness of knowledge and great depth of sympathy, have laid
before geologists and the public the lives and labours of those great pioneers who
have accumulated the vast store of knowledge which we now possess of the rocks and
fossils of the Dominion.
As an old friend and correspondent of yours, I am very pleased that it has fallen
to my lot to hand you this Medal; and I can assure you, on behalf of the Council
of the Geological Society of London, that it is a special gratification to them to award
it to one whose work has been done in the country of the founder of the Medal
himself, and among the rocks and fossils studied by him.
Dr. Ami replied in the following words :—Mr. President,—
I am deeply sensible of the great honour which the Council of this Society has
conferred upon me. Especially am I gratified in receiving this award at the hands of
one who has been so generous a counsellor and critic in matters geological for the
past eighteen years. Words fail me to express in adequate terms the gratitude which
fills me at present. Suffice it to say that, through the liberality of the Canadian
Government and courtesy of the Hon. the Minister of the Interior (Mr. Cliitord
Sifton), Head of the Geological Survey Department at Ottawa, I have acceded to
his wishes, and come over in person to receive at your hands the award so
generously made.
It is always a source of inspiration to come to London, the centre of thought,
the fountain-head of research, and radiator of power; and, believe me, that, combined
with the pleasure and privilege of attending one of the anniversary meetings of this
Society, of which I have been a humble Fellow for some eighteen years, there:
lurked in my mind the thought of gain in valuable information during my stay,
which I know will enable me all the better and more intelligently to carry out the
special work on the Silurian faunas and succession of Eastern Canada which has.
been entrusted to me.
That my name should become associated with that of the late Dr. Bigsby, founder
of the Medal, is a matter of which I have great reason to be proud. Bigsby was
a pioneer in British North American geology. It has been my lot and good fortune
recently to collect all the data relating to the geological history of the Grand
Manitoulin and adjacent islands of Paleozoic age in the Lake Huron district of
Canada, and it may not be uninteresting to state here that, when the unexpected
news of this award reached me in Ottawa, I had then completed, and on my desk,
a synopsis of Dr. Bigsby’s geological explorations in that region during the early
years of the last century.
In conclusion, permit me to add that I am deeply moved at this moment by the
thought of what the acceptance of the Bigsby Medal on my part involves. ‘There
is undoubtedly associated with it a solemn pledge and obligation to prosecute
geological research-work still farther. If I am spared, Sir, it will be my highest
endeavour as well as pleasure and privilege to follow in the footsteps of those
eminent geologists in the distinguished list of recipients of the Medal founded
through the generosity of the late Dr. Bigsby, and prove not unworthy of the
marked distinction that the Council have conferred upon me this day.
The President, in handing the Prestwich Medal, awarded to
John, Baron Avebury, P.C., F.R.S., to Professor T’. G. Bonney, D.Sc.,
F.R.S., for transmission to the recipient, addressed him in the
following words :—Professor Bonney,—
Sir John Lubbock, now the Right Hon. Lord Avebury, P.C., became a Fellow
of this Society in 1855. He was one of those who took a warm interest in the
question of the antiquity of man, in those early days when it was so much in dispute..
He did much to support the new views, not only by a paper in the Natural History
Review, but also by his work on ‘‘ Prehistoric Times,’’ in which that paper was
subsequently incorporated. In those days he was closely associated with Sir Joseph
Prestwich (who at that time had not yet been called to the professorial chair at Oxford),
and, along with Sir John Evans, frequently accompanied him and other Fellows of
the Society on geological excursions in France and elsewhere, investigating not only
the evidences of the antiquity of man, but other problems of special interest in geology...
Reports and Proceedings—Geological Society of London. 183
Since then, notwithstanding his numerous public ayocations, his important business
occupations, and his researches in natural history, both entomological and botanical,
he has always retained a lasting attachment to geology. He has evinced this, not
only in keeping abreast with its progress and accompanying its workers in the field,
but also in the publication of works on geology, marked by his own literary charm.
His recent works on the scenery of Switzerland and of England have done much to
create a deep appreciation and sympathy for the science among the thinking and
educated public.
Whether, therefore, from old associations, or from the special nature of his
geological researches, or from the fascination of his geological works, the Council
of the Geological Society feel that he is a most fitting recipient of the first gold
medal struck in accordance with the testamentary dispositions of our venerable Fellow,
Sir Joseph Prestwich.
Professor Bonney, in reply, read the following letter which had
been forwarded to him by the recipient :—Mr. President,—
““T should have felt it a great compliment in any case that the Geological Society
should have bestowed upon me one of their medals, but I am specially gratified to
have received the first of the Medals instituted in honour of my old friend Sir Joseph
Prestwich. It is now more than forty years since I first visited the valley of the
Somme under his guidance and that of M. Boucher de Perthes. Since then I have
had the advantage of making many most instructive excursions with him. On those
occasions we were out early and late. Meals constantly gave way to gravel-pits.
On one occasion I spent a week with him in Paris—at least, if we can be said to
have been in Paris, when I think that we were never there between 7 o’clock in the
morning and 8 in the evening; and I look back on those expeditions with the greatest
interest. I shall value the Medal extremely, both as a mark of the approval of the
Council, and also in memory of one whom I esteemed so highly, and to whom I owed
so much. It is a matter of great regret to me that absence from England has:
precluded me from attending to receive it personally.”’
The President then presented the Balance of the Proceeds of the
Wollaston Donation Fund to Mr. L. L. Belinfante, M.Sc., Assistant
Secretary of the Geological Society, addressing him as follows :—
Mr. Belinfante,—
At a meeting of Fellows of the Geological Society it is quite unnecessary for me
to say anything as to your merits. You stand here among friends and well-wishers,
to all of whom you are well known as the capable Assistant Secretary of the Society.
But perhaps it is to the Council alone, and more particularly to those who have
served as officers, that the full extent of the indebtedness of the Society to you is
known. You combine the offices of Assistant Secretary, Clerk, Librarian, Kditor of
the Journal, and Curator of the Museum, and each of these offices, whether the
duties are performed by you personally or under your general supervision, are filled
to the great advantage of the Society. Authors of papers owe you a deep debt of
gratitude for the help that they have received from you in editing their papers ;
indeed, such trust have they in your judgment that they are almost too lable to
leave the whole of the burden of seeing their papers through the press in your hands.
If it were necessary for me to allude to actual geological work done by you, I have
only to mention the Index to the first Fifty Volumes of the Quarterly Journal, which
was completed by you outside your official hours, and has proved of immense value to
all writers in geology. But in handing you this award of the Wollaston Donation
Fund, I trust rather that you will receive it as a mark of appreciation by the
Council and Fellows of your able and conscientious services to the Society and to
geology as Assistant Secretary and Editor of the Journal, and I can only conclude with
the hope that we may have the advantage of your services for many years to come.
The President, in handing the Balance of the Proceeds of the
Murchison Geological Fund, awarded to Mrs. Elizabeth Gray, of
Hdinburgh, to Dr. Henry Woodward, F.R.S., for transmission to the
recipient, addressed him in the following words :—Dr. Woodward,—.
Mrs. Gray has devoted the leisure hours of nearly half a lifetime to collecting in
the field and arranging in her cabinets the fossils of the Ordovician and Silurian rocks,
184 Reports and Proceedings—Geological Society of London.
of the Girvan district of Ayrshire. The paleontology bears so closely on the structure
of this complicated region, that a detailed knowledge of it is indispensable to any
geologist who attempts to unravel that structure.
Her collections have been of more than ordinary value, because of the careful
record that she has kept from the first of the exact locality and horizon at which each
fossil was collected. She has generously placed her specimens at the disposal of all
geologists and paleontologists engaged in the study of the Paleozoic rocks and fossils,
and a large number of them have been described in the monographs of Davidson,
Nicholson, Etheridge, and others. When working in the Girvan district, the officers
of the Geological Survey of Scotland checked their own collection by that of
Mrs. Gray, and paid a well-earned tribute to its value by publishing in their memoir
on the Silurian Rocks of Southern Scotland a full list of all her fossils supplementary
to their own. My own personal indebtedness to the collections made by Mrs. Gray
and her family, when I was working at the geology of that district, was especially
great; and it affords me no ordinary gratification to be able to hand to you, for
transmission to her, the Balance of the Proceeds of the Murchison Geological Fund,
on behalf of the Council of this Society.
Dr. Woodward, in reply, read the following letter which had beer
forwarded to him by the recipient :—
“< Dear Dr. Woodward,
“T am gratified to learn that you intend to be present at the anniversary meeting
of the Geological Society, and I thank you for your kindness in allowing me to
nominate you to receive for me on that occasion the Murchison Fund, awarded by the
Council of the Society in consideration of what they too generously characterize as
‘ great services to Geological Science.’
“*My work in the Girvan district, among the fossils of the Silurian rocks, has been
to me a lifelong pleasure, augmented of late years by the knowledge that my collection
has proved of service to the Geological Survey of Scotland, as well as to individual
geologists—to name among these but the late Dr. Thomas Davidson.
“¢J¢ is incumbent on me, however, to record that my husband, the late Mr. Robert
Gray, taking a keen interest in my pursuits, shared with me during many years the
agreeable task, not only of searching for fossils, but of helping to work them out
when found, so that it is difficult for me, in the present circumstances, to repress
a pang of regret that he cannot likewise participate in my satisfaction at the Geological
Society’s very gracious recognition of what, to some extent, was our joint work.
“¢T value very highly the honour conferred upon me, and beg you to convey to the
Council my grateful thanks and sincere acknowledgments.”’
The President then presented part of the Balance of the Proceeds
of the Lyell Geological Fund to Mr. George Edward Dibley,
addressing him as follows:—Mr. Dibley,—
You have, for a number of years, devoted the leisure hours of a busy life to the
careful collecting of fossils from the Chalk, and have thereby added much to our
knowledge of the distribution of species in the several life-zones. The results of
these labours have been partly published in the Proceedings of the Geologists’
Association, and they include the record of the discovery of a specimen of especial
interest, as it is believed to be a representative of the lizard-like Rhynchocephalia, no
example of which has been previously recorded from the Chalk.
I have much pleasure in handing to you a moiety of the Balance of the Lyell Fund,
which has been awarded to you by the Council of this Society.
Mr. Dibley replied in the following words :—Mr. President,—
I beg to thank the Council of the Geological Society most heartily for their kind
appreciation of my efforts to further the accurate knowledge of our Cretaceous geology
by the systematic and patient collecting of fossils zone by zone, a method of research
so clearly demonstrated by you, Sir, in the older Paleozoic rocks. I can assure you
that it is a delight to me to be able to devote each week-end to this branch of natural
science ; and | only trust that I may be spared to continue my labours on new ground
as well as on the old, so that I may be of further use in promoting the advance ot
geological science.
I may perhaps be allowed to add that, in thanking you for this honour conferred
upon me, it gives me especial pleasure to receive it at your hands.
Reports and Proceedings— Geological Society of London. 185
The President, in handing the remainder of the Balance of the
‘Proceeds of the Lyell Geological Fund, awarded to Mr. Sydney S.
Buckman, to Dr. Bather, M.A., for transmission to the recipient,
-addressed him in the following words :—Dr. Bather,—
In the year 1897 the Council of the Geological Society awarded to Mi Buckman
the proceeds ot one of their Funds, in acknowledgment of the important work which
he had already accomplished among the Jurassic Invertebrata, and of his investiga-
tions into the stratigraphical details of their containing formations, expressing their
-confidence that he would be certain to continue and extend that work.
Their confidence has been more than justified ; for since that time, not only has
he issued important supplements to his Monograph on the Inferior Oolite Ammonites,
published by the Paleeontographical Society, and continued his stratigraphical studies
-on Dundry Hill, and on the Bajocian and Contiguous Deposits in the Northern
Cotteswolds, but he has broken new ground in his memoir on ‘‘ Homceomorphy
-among Jurassic Brachiopoda,’’ that will doubtless have far-reaching results. He
has also published interesting and suggestive papers upon river-development, especially
~with regard to the genesis of the Severn and the Wye. e
For a quarter of a century he has devoted his energies and genius to the advance
of geology and palsontology, and each year he has presented to science something
valuable and original. The Council of the Geological Society, while sensible of the
imadequacy of this recognition of his labours, hope that he will accept it as an earnest
-of their appreciation of his scientific work.
Dr. Bather, in reply, said :—Mr. President, —
In receiving this award on behalf of my friend Mr. Buckman, it had not been my
intention to depart from the precedent that commends silence to the recipients of
funds as the most suitable expression of their gratitude ; in fact, I took care to leave
at home the speech he wrote out for me. But since this somewhat recent precedent
has twice been broken this afternoon, I might seem wanting, both in courtesy to
yourself and in loyalty to Mr. Buckman, if I did not give the gist of his remarks.
Mr. Buckman is aware that his paleontological work, especially that relating to
_Ammonites, has met with considerable criticism. He is therefore particularly gratetul
for this recognition on the part of the Council of the Geological Society. The
principles that have animated his work on the Ammonites have been applied by him
also to the Brachiopods. They are, in fact, principles that are working a vast
revolution in the whole of paleontology. The interpretation of the phenomena of
homeomorphy—that is to say, the appearance of species, often at different periods,
-perplexingly similar in outward form though descended from different stocks—will
lead to much more exact identification of fossils. This preciser paleontology, in
conjunction with field-work among the Secondary rocks on the lines indicated in
Mr. Buckman’s last paper contributed to this Society, will, he is confident, have
-a distinct practical value, since it is bound to throw light on the position of concealed
coal-basins. Unfortunately, such wealth as may be obtained in consequence of this
purely scientific research will, under present laws, fall not to the nation but to land-
owners; least of all will the students, to whose researches it is due, receive any
material benefit—except, perhaps, such an award as this, for which I have to offer
ito you, Sir, Mr. Buckman’s sincere thanks.
The President then proceeded to read his Anniversary Address, in
which he first gave obituary notices of several Fellows deceased
since the last annual meeting, including the Rev. Professor
T. Wiltshire (elected a Fellow in 1856), Dr. A. R. C. Selwyn
(elected in 1871), Mr. J. C. Mansel-Pleydell (el. in 1857),
Mr. W. H. Penning (el. in 1868), Mr. W. Gunn (el. in 1876),
Mr. J. Macpherson (el. in 1890), Mr. A. Vaughan Jennings
(el. in 1891), Mr. J. Landon (el. in 1887), Mr. A. L. Collins
(el. in 1892), Major J. W. Powell, Foreign Correspondent (el. in
1892), Mr. A. Hyatt, Foreign Correspondent (el. in 1897), Lord
Pirbright (el. in 1861), Mr. F. Stevenson (el. in 1877), and
Dr. Hugh Exton (el. in 1883).
186 Reports and Proceedings—Geological Society of London.
He then dealt with the relation of geology to its fellow-sciences..
Astronomy and geology—one the oldest, the other the youngest
of the sciences—have both a comparatively small number of
adherents and working members. One suggests to the mind of man.
ideas of infinity, and the other those of eternity ; but while the
former ideas have found ready acceptance, the latter have had to.
struggle against much reluctance on the part, not only of the average
man, but of physicists and mathematicians, and even of geologists.
themselves, and this in spite of the fact that some of the most fertile
principles of geological science have had their spring in a conviction
of the immensity of past time.
Geology has relations with mineralogy, physics, geography, and
biology ; but though fearlessly acknowledging how much it has
borrowed from each of these sciences, it can claim that the debt has
in every case been repaid with interest. ‘To mineralogy it has given
the associations and relations of minerals in the crystalline rocks 5.
to biology, the strongest proofs of organic evolution and the stages.
of its advance; to geography, the explanation of the origin of the
earth’s surface-features, and the foundation of the study sometimes.
called ‘geomorphology’; to physics, the facts with regard to the
deformations of the earth’s crust, which still await a theoretical
explanation.
The study of geology shows that the corporate geological organism.
has three necessary functions—research, practice, and education.
So long as all three functions are naturally and healthfully per-
formed, so long will geology live and flourish. The work and
influence of Werner and De la Beche show that the progress of the
science is at its swiftest and surest when none of the three functions.
suffer from disuse.
In its relations to the thoughts of mankind and ideas of life, what
gives character and its especial colour to the science of geology is
that it is the exponent, or practically the discoverer, of the idea of
continuous evolution, ‘‘ for he discovers who proves.” To a student
who has gone through a geological training and appreciated its
meaning, the idea of slow and continuous evolution becomes part and
parcel of his mental constitution, and he carries this conception into
his other studies. In all cases he is on the watch for those
simple natural causes that are capable of the present accumulated
effects; he is watching the development of a living being growing
up, as it were, before his mental vision. It is therefore to be desired
that some knowledge of this kind should reach the ordinary man of
education and leisure, as well as the specialist, for it tends to restore:
the loss of balance due to the self-absorptive and introspective
tendency of much of our present-day culture.
Some such geonomic training or earth-knowledge is essential in
any complete scheme of education—at first hardly differentiated into
geology and geography, but later passing on to the study of
topography, geography, and geology. The training should be in the
early stages experimental and practical, bringing out all that can be
shown upon maps and learnt from them; but the didactic side must
Reports and Proceedings-— Geological Society of London. i8T
not be neglected, particularly in those years of life when a student is-
most qualified to profit by it, because the facts of science are so
many, and the grandest conclusions are so dependent on the higher
stages of knowledge.
The veil of ignorance and of traditional opinion which hid from
the view of the Middle Ages the wonders which geology has since
revealed, was so opaque that, until the close of the eighteenth century,
no light could penetrate beyond. But so old and flimsy was it that,.
when once the strong hand of the geologist had torn it, it was rent
from top to bottom, and in the flood of light which entered discovery
followed discovery in endless succession. These discoveries have
benefited not only geology but all its fellow-sciences, and have been
of supreme importance to man himself.
Therefore, as geology goes hopefully forward into the new era
now opening out before it, its students should never forget that their
science is not only the interpreter of Nature, but also the servant of
Humanity.
The ballot for the Council and Officers was taken, and the following were declared
duly elected for the ensuing year :—Cowncil : The Right Hon. Lord Ay ebury, P.C.,
ID Gollo, Ihibe Dos IM Rosie IIIs IBS Jae lstndaverc, M. AY. DeSces Wi: T. Blanford,
LED. ER.S.5. Sit John Kyans, K.C.B.. DiC. TULA F. R.5S Professor
E. J. Garwood, M.A. ; Sir Archibald Geikie, DEScV DEC De Ey R. ’s. L. &E. ;
Professor T. T. Groom, MRCAU DES Cons ; Alfred Harker, Esq., M.A. ERS.) Ras:
Herries, Esq., M.A.; R. Logan Jack, JD) b eID) 5 ; Professor J. W. Judd, C.B., itt. D.,
Wo Sesmbercy, hi; Kendall, "Esq. ; Protessor "Charles Lapworth, Till pID) bg Iolttalsie 8
Lieut.-General C. A. McMahon, F.R. 8. 5 J. EH. Marr, Esq., M.A., F. R.S
Professor H. A. Miers, M.B., F.R.S. IL. W. Monckton, Esq., F.LS. ; 3119, .
Newton, Esq., F.R.S.; G. T. "Prior, Tee M.A.; Protessor H. G. Seeley, F.R.S
Be Ses Professor W. J. Sollas, M. A. DE Se. Lely 10), pldslteshs dedi. del, abseil, Esq. ;
M.A., F.R.S.; Professor W. W. Watts, M.A.
Officers :—President : Prof. Charles Lapworth, LL.D., F.R.S. Vice-Presidents :
Sir Archibald Geikie, D. Gop IDCllbing JulbalDa, Italie 8. ib & E.; Protessor H. A.
Miers, M.A., F.R.S.; KE. T. Newton, Ksq., "ERS .; and J. J. H. Teall, EKsq.,
M.A., F.R.S. Secretaries: RB. 8. Herries, Ksq., M.A., and Professor W.. W..
Watts, M.A. Foreign Secretary: Sir John Evans, K.C.B., D.C.L., LU.D.,
F.R.S., F.L.S. Zreasurer: W.T. Blanford, LL.D., F.R.S.
The thanks of the Fellows were unanimously voted to the retiring
Vice-Presidents, Mr. J. E. Marr and Professor H. G. Seeley ; and to.
the retiring Members of Council, Mr. W. H. Hudleston, the Right
Rev. John Mitchinson, Dr. D. H. Scott, Mr. A. Sopwith, and
Dr. Henry Weedwasd:
I].—February 25th, 1903. Moree Gleces Lapworth, LL.D.,
F.R.S., President, in the Chair. The following communications
were read —
1. “On the Occurrence of Dictyozamites in England, with Remarks
on HKuropean and Eastern Floras.” By Albert Charles Seward,
Hsq., M.A., F.B.S., F.L.S., F.G.8., Fellow of Emmanuel College,
Cambridge.
The specimens described as a new species of Dictyozamites were
obtained from a bed of ironstone, low down in the Hstuarine Series,
on the northern face of the Upleatham outlier, near Marske-by-the-
Sea, by the Rev. John Hawell, F.G.S. The genus is also found in
188 Reports and Proceedings—Geological Society of London.
the Rajmahal Series of India, in Central Japan, and at Bornholm.
Its probable taxonomic position is best expressed by placing it as
a member of the Cycadophyta.
The author proceeds to a comparison of the Bornholm, Indian,
Japanese, and English floras; and as resemblances are masked by
the use of different generic or specific names for plants which are
either identical or represent closely allied members of the same
family, a special list of these floras has been prepared, in which,
while the names at present in use are indicated, it is pointed out
where obscured identities or resemblances exist. From this com-
parison the author concludes that there was a greater similarity
between the vegetation of Hastern and Western regions, during
part at least of the Mesozoic Era, than is usually admitted; while
the differences between Mesozoic floras of approximately the same
geological age are for the most part slight and unimportant, when
their wide geographical separation is considered. Equisetaceous
plants are practically ubiquitous ; several ferns of apparently the same
species occur in the Far Hast and in Western Europe; cycadaceous
plants are represented by cosmopolitan types, and the same may be
said of the genus Araucarites and other members of the Conifere.
The most noteworthy exceptions are afforded by the Mesozoic repre-
sentatives of the two isolated recent ferns MJatonia and Dipteris ;
these two families—each with a surviving genus—played a con-
spicuous part in the vegetation of the Rheetic and succeeding Jurassic
Epochs in Europe, and to a less extent in North America, but there
are no satisfactory records of their existence in India or Japan.
A similar state of things is illustrated by the Ginkgoales, the class
of which the ‘ maidenhair-tree’ of China and Japan forms the solitary
survivor; the abundance of both Ginkgo and Baiera in the Mesozoic
of Europe is in striking contrast to their almost complete absence
in India.
«The Amounts of Nitrogen and Organic Carbon in some Clays
and Marls.” By Dr. N. H. J. Miller, F.C.S. (Communicated by
Sir John Evans, K.C.B., D.C.L., F.R.S., For. Sec. G.S.)
Analyses of soils are given to show that, under most conditions,
decaying vegetable matter in soil tends to become more nitrogenous,
on account of the greater ease with which gaseous compounds are
formed with carbon than with nitrogen. Hilgard’s experiments
throw light on the effects of extreme conditions of climate, the
amount of soluble humus being much greater in soils in humid than
in arid climates; thus, although the total amount of soluble nitrogen
does not vary much, the percentage of it in the humus varied very
considerably in the two cases. The large areas of peat-land known
as ‘Hochmoor’ contain larger proportions of carbon and nitrogen at
depths of 7 and 14 feet than at the surface. The organic matter of
soils is of two kinds—the humous portion and the bituminous; the
latter being regarded as belonging to the original deposit from which
the soil is derived. Analyses of soils and subsoils are given to
illustrate this point. Further light on this subject is derived from
the analysis of a series of specimens from the following deposits,
Reports and Proceedings—Edinburgh Geological Society. 189
obtained through the kindness of Sir Archibald Geikie from borings
in the possession of the Geological Survey: Lower Lias, Oxford
Clay, Kimmeridge Shale, Purbeck and Wealden strata, Gault, Chalk
Marl, and London Clay. Apart from the interest due to_the great
depths from which the samples were obtained, and the evidence which
they afford of the enormous accumulations of combined nitrogen, they
possess the further and greater value of representing the materials
out of which large areas of soils have been derived. Calcium-
carbonate varies from 82:1 to 0 per cent., organic carbon from
1:229 to 0°229, and nitrogen from 0068 to 0-021; the highest
proportion of carbon to nitrogen is 40:5 to 1, and the lowest
8:9 to 1. It would be important to determine, in the case of these
older deposits, whether any of the organic matter at all is in the
form of humus.
JIJ.—Mrneratocican Society, February 3rd.—Professor H. A.
Miers, F.R.S., Vice-President, in the Chair. Mr. L. Fletcher gave
an account of the fall of a meteoric stone on August 22nd, 1902, at
Caratash, Smyrna; and also contributed a note on the history of
the mass of meteoric iron found in the neighbourhood of Capera,
Patagonia. Mr. H. L. Bowman gave the results of determinations
of the refractive indices of pyromorphite and vanadinite by means
of artificially ground prisms having an angle of about 30°. For
red light the refractive indices of pyromorphite were w = 2:139,
e = 2:124; and of vanadinite, w = 2°354, e = 2:299. Mr. T. V. Barker
described quartz crystals of peculiar habit which were collected by
Lieut. E. G. Spencer-Churchill near De Aar, South Africa. Two
crystals were remarkable as exhibiting faces seldom observed on
quartz, one in the zone mz and the other in the zone rz.
IV. — Epinsuren Geonocican Society. Special Meeting,
Sth February, 1903. Dr. Horne, F.R.S., in the Chair. Lecture
on “The Fassa-Monzoni District, or Simultaneous Duplex Crust
Movements.” By Mrs. Ogilvie Gordon, D.Sc., Ph.D., Aberdeen.
The lecture was illustrated by Mrs. Gordon’s lantern views,
geological maps and sections, rock specimens, and mineralogical
slides. In describing the succession of Triassic strata Mrs. Gordon
pointed out two distinct advances made by her work—(1) She had
discovered the presence of Wengen-Cassian marls with characteristic
fossils in the midst of the Middle Triassic limestones, whereas
hitherto these fossiliferous marls had been reported to be absent
in Fassa; (2) she had determined the presence of a definite band of
fossiliferous marls and crinoidal and oolitic limestones between the
Lower and Middle Trias, as a constant member in all undisturbed
sections. Hitherto these limestones had been regarded as un-
fossiliferous, and described as a rarely present, abnormal facies of
the lower horizons of Middle Triassic limestones. The establish-
ment of this definite passage zone between Lower and Middle Trias.
was an important addition to the geology of South Tyrol. Further,
it corresponded to the horizon of ‘ Reichenhall limestone’ and the
‘Myophoria beds’ in North Tyrol, and probably also to the well-
known ‘ Roth’ horizon in the North German Trias. Throughout
190 Reports and Proceedings—Edinburgh Geological Society.
the Tertiary crust movements in the Alps this passage zone had
been the great crush-zone of the district. It occurred in Fassa
below a massive development of calcareous rocks, and above an
almost equal thickness of mixed deposits; it was therefore a well-
marled ‘critical ’ zone within the earth’s crust, interleaved between
rock material, presenting strongly contrasted physical characters.
The maximum deformational effects had been attained at this zone,
and in the other leading ‘critical’ zone presented by the Wengen-
Cassian marls. Innumerable planes of overthrust and downslip had
developed within these bands, some with only 10 degs. to 20 degs.
inclination, others much steeper. Vast eruptions of molten rock
had found their way into these deformational zones, and con-
solidated in the form of wide sheets and sills at those definite
horizons within the Triassic succession. ‘Thus, one of the general
results of her detailed survey had been to disprove the previous
conception that the porphyrite rocks in Fassa had originated as
surface outflows in Triassic time, and to show that they had been
intruded into the local fault lines and planes of crust deformation
which developed during middle and late Tertiary Alpine move-
ments. A similar result had been obtained several years ago by her
for the area on the north. The previous investigators had failed to
recognize the presence of the innumerable crust planes with
extremely low inclination, and consequently overlooked the corre-
lation of the igneous invasions with pre-existent deformational
structures. After indicating on the map the complete sequence of
the igneous rocks at Monzoni, Mrs. Gordon proceeded to describe
her new results regarding cross-fold formation. Several folding
movements had affected this district. In the first place, undulations
directed east and west had formed with a steep southern face and
a long northern slope, the width of an undulation being about
41 miles. These had been deformed by oblique cross-folds, which
developed simultaneously along two directions, E.N.H.-W.S.W. and
W.N.W.-E.S.E. During these movements the steep south faces of
the original plications were overthrust towards 8.S8.H. and 8.8.W.,
and the first inrush of molten rock occurred into zones of crust
attenuation and fracture. Still later, another duplex system of
cross-folds was superinduced rectangularly upon the earlier in
N.N.W.-S.S.E. and N.N.E.-S.S.W. directions. Overthrusts and
shear-slips took place again, and fragmented the previous thrust
masses and igneous intrusions. Mrs. Gordon showed by reference
to her map that the most intense effects of crust deformation had
been coeval with this advanced stage in the superposition of duplex
deformational systems upon the original and fundamental east-west
undulations. A subsequent epoch of crust adjustment and surface
erosion had ensued, characterized by local subsidences taking place
pre-eminently along the previous crust fractures. Local crumplings
had then occurred around large masses of igneous rock or the larger
deformation fragments of Triassic limestone. Small igneous inter-
calations of highly differentiated rock materials accompanied these
inthrows. Mrs. Gordon’s interpretation of this remarkable series of
cross-folds was based upon the principle of the simultaneous action
Correspondence—R. Ashington Bullen—Dr. Callaway. 191.
of paired resultant strains, acting along N.H.-S.W. and N.W.-S.E.
directions, the precise directive angle varying in proportion as the
east-west or the north-south stresses due to crust compression were
the more powerful, and also in accordance with particular local
modifications of the regional strains. At the close a vote of thanks
was cordially given to Mrs. Gordon.
CORRESPONDENCE.
EOLITHS FROM SOUTH AND SOUTH-WEST ENGLAND.
Sir,—Kindly insert the following correction and addition to my
paper on “ Koliths from South and South-West England” in the
March number.
1. Corrigendum.—Instead of Bat’s Corner read Kettle’s Corner,
Parsonage Farm (Chapel Croft Field), near Ash. Mr. Harrison
informs me that it is so marked in the 6 inch map of the district.
Bat’s Corner was the name given me on December 24th, 1894, when
I visited the pit with Mr. Harrison, but as tenants change so do the
names of their farms. Probably Kettle was the name of a former
tenant.
2. Addendum (Bibliography), with sincere apologies for the
omission.
1899. Newton, H. T.— Presidential Address to the Geologists’? Association,
February 5th, 1897: Proc. Geol. Assoc., vol. xv, pp. 69-72.
1902. Haddon, A. C.—‘‘ Karly Man and his Life,’’ third paper: National Home
Reading Union Magazine, p. 46.
Pyrrorp, March 6th, 1908. R. Asnineron BuLuen.
THE ORIGIN OF THE ARCHAAN ROCKS.
Srr,—Some references to the Archean rocks made by Mr. G. W.
Bulman in the Gronoeicat Magazine for March (p. 126) call for
a word of comment. I do not understand what he means by “ pre-
Archean deposits.” There are no rocks older than the Archean,
whether we use the term as equivalent to ‘pre-Cambrian” or
limit it to the “ Fundamental Complex.” Then he remarks that
“Geologists are yet sorely perplexed with the problem of the
Archean rocks. They have not yet decided whether they are
metamorphosed ordinary sediments, [or ?] part of the original
solidified crust of the earth, or chemical precipitates from a hot
primitive ocean.” But these alternatives are not the problem.
There is no perplexity whatever about a large proportion of the
Archean rocks. The Longmyndian and Torridonian are known to
be mainly sedimentary; the groups identified as Pebidian, Uriconian,
and Charnian are known to be predominantly volcanic; and the
rock-masses called Malvernian and Hebridean are generally admitted
to be igneous plutonics. AASE
196 FE. R. Cowper Reed—On Brachymetopus.
trilobites with spinose and non-spinose representatives. The fewer
number of segments in the pygidium and the raised spinigerous
border separate it from all the European forms. The genus or
subgenus Phaetonides, as now understood, is partly distinguished
for analogous reasons from the typical Proetus; and it seems open
to question whether the European species of Brachymetopus should
not be regarded as constituting a distinct group or subgenus, for
which the name Brachymetopina may be suggested. Oehlert,’ in his
review of the genus Brachymetopus and its allies, does not mention
any species with a spinigerous margin to the pygidium; and
Claypole? was convinced that with the single possible exception
of Phillipsia lodiensis, Meek, and Dalmanites (?) Cuyahoga, Claypole
(see below), every Carboniferous trilobite on either side of the
Atlantic possessed a pygidium with a definite even outline. Von
Moller * compared the Australian species Br. Sirzeleckit with Russian
forms, but in his description ascribes to it too many pygidial segments.
It is worthy of remark that he figures (op. cit., t. ii, fig. 32) a head-
shield (doubtfully attributed to Br. ouralicus) which shows the
circle of tubercles round the eyes, the pair of large tubercles in
front of the glabella, and one median tubercle on the glabella, which
are features well marked in Br. Strzeleckit.
It is, however, specially interesting to find in the Waverly Group
(Carboniferous) of North America members of the genus Brachymetopus
with spinigerous pygidia like the Australian species. Such are
Br. lodiensis, Meek,* from the Cuyahoga Shales of Ohio, of which
Herrick’ expresses a doubt whether it is a true Brachymetopus ;
Br. spinosus, Herrick,® and probably Br. immaturus, Herrick,’ and
Br. occidentalis,’ Herrick, the three latter of which were referred
by Herrick to the genus Phaetonides.° There is also Br. armatus,
Vogdes,”° from the Waverly of Missouri, with a single pair of spines,
and Br. Cuyahoga, Claypole, which according to Vogdes (op. cit.) is
only an imperfectly preserved example of Brachymetopus, and not
one of the Phacopidx.
As McCoy’s figures of Br. Siérzelecki: are not very clear, and
Plews’" figure is misleading, a restoration, based on the types, is
here given of the head-shield and pygidium. (Figs. 1, 2, p. 194.)
The species has been recorded by Etheridge, jun. (Cat. Austr.
Foss., Camb. 1878, p. 41), from Dunvegan, Burragood, and Glen
William, all in New South Wales.
! Oehlert: Bull. Soc. Et. Scient. Angers, 1885, p. 10 (extract).
2 Mon. Brit. Carb. Trilob. (Paleont. Soc., 1884), p. 77.
3 Von Moller: Bull. Soc. Imp. Nat. Moscou, xl (1867), p. 145.
* Rep. Geol. Surv. Ohio, vol. ii, Geol. and Paliont., 1875, p. 323, pl. xvii, fig. 3
[Phillipsia (Griffithides ?) lodiensis, Meek].
5 Herrick: Bull. Denison Univ., vol. ii, pt. 1 (1887), p. 57.
6 Tbid., vol. iv (1889), p. 58, pl. i, figs. 4, 5; and Bull. Geol. Soc. Amer.,
vol. ii (1891), p. 42, pl. i, fig. 13.
7 Thid., vol. iv (1889), p. 59, pl. i, figs. 9-15. -
8 Tbid., p. 57, pl. i, figs. 10a, 0b.
® Vogdes: Bibliogr. Paleeoz. Crust. (Occas. Papers Calif. Acad. Sc.), 1893, p. 284..
10 Vogdes: Trans. St. Louis Acad. Sc., vol. v (1892), p. 617, pl. xv, figs. 4, 5.
11 Plews: Trans. N. Engl. Instit. Min. Engin., vol. vi, p. 34, pl. iv.
W. H. Hudleston—Creechbarrow in Purbeck. 197
I].—CrercHBarrow In Purseck.—No. 2 (continued).
By W. H. Hupzezston, M.A., F.R.S., F.G.S.
(PLATE XI.)
(Concluded from the April Number, p. 154.) =
Varieties of the Creechbarrow Limestone.—There are considerable
extremes in this respect, ranging from a soft marly deposit, which
soils the fingers like whitening, to a hard compact rock, which takes»
a good polish. Unquestionably the most dense and compact lime-
stone is that near the summit, whilst the soft marly beds are on the
northern slope, and especially near the 500 feet contour, where some
of them are earthy and contain a considerable amount of impurity,
so that they may at least be called marly limestones. On the other
hand, there are compact white limestones, where nests of dog-tooth
spar form no inconsiderable portion of the mass. Quartz grains may
be noted on most of the weathered surfaces.
The more compact and denser limestones, which prevail near the
summit, may be roughly divided into non-pisolitic and pisolitic
rocks. Thus, for instance, I have before me (Group 1) specimens
of a very heavy and partially calcitic rock. It is a hard whitish
limestone without pisolites, but largely interspersed with buff-
coloured patches, not unlike some dolomites. Calcitic nests and
strings occur, and also strings and stars of black oxide of
manganese: the external surface is rough and somewhat honey-
combed, and full of curious impressions, some of which may have
had an organic origin.
Group 2 comprises those specimens where the pisolitic character
is indicated, but not very obviously. A characteristic specimen may
be described as follows:—A large fragment of a creamy white
tufaceous limestone, with specks and threads of black oxide of
manganese in places: flattened pisolitic bodies in brownish calcite
are numerous, but not very distinct. There are casts of interiors of
a univalve shell, which is most probably Paludina. The whole
of this fragment has a tufaceous aspect, and is free from buff-
coloured patches. The external surface is rough, and in one corner
is full of curious shapes, which are doubtless concretionary bodies
developed by weathering. On further examination of these curious
shapes, I note indications of the concentric structure which convinces
me that they are pisolites developed by weathering.
The Pisolites.1 (Group 3.)—Originally I divided these limestones
into four groups, but the pisolitic limestones may be taken as
one group. The following is the description of a specimen of this
class of rock.
A creamy tufaceous limestone with some buff-coloured patches and
with specks and threads of manganese oxide. Sections of ordinary
pisolites here and there. But this specimen is remarkable for three
very large horseshoe sections, which certainly represent concretions
in brown calcite. The first specimens I obtained were incomplete
1 The accompanying Plate is intended to illustrate concretionary or pisolitic action
as well as to serve the paleontology of the limestone.
198 W. H. Hudleston—Creechbarrow in Purbeck.
in outline, thus causing an appearance of being open at one end, like
a horseshoe. Specimens subsequently obtained showed that this.
was not exactly the case. Where the periphery of the section is
complete, as in the specimen figured on Plate XI, Figs. 2 and 3,
it is seen that the section of this large concretionary body is thick at
one end and thin at the other. Fig. 38 of the Plate especially
shows a side view of this curious body, where, taken by itself alone,
it might almost be regarded as a fragment of a big belemnite. The
section shows a series of concentric rings of brown calcite with
a large hollow in the centre filled with the ordinary matrix. There
is no radial structure ; one end of the circle, as previously noted, is.
thick, whilst the opposite end thins out to such an extent that
in some specimens it is not to be traced. Some of these ‘ horse-
shoe’ sections are nearly 14 inches in diameter.
The Egg-like Body. (Plate XI, Fig. 4.)—For a long time these
so-called horseshoe concretions were a puzzle to me, and as they
were for the most part only obtained in fragments, there seemed to
be no possibility of solving the enigma. At last, by good luck we
stumbled on a still more curious body, which is perhaps the most
perfect pisolite ever discovered. In this case we perceive a pisolitic
concretion with an interior like a very small egg, of which the
shell, represented by the concentric layers of brown calcite, is
developed so obliquely that it is quite thick on one side and thin on
the other side. This specimen has been broken so fortunately that
we recognize our horseshoe section at once, with the matrix in
the form of an ege projecting from the unequally developed circle.
Those who regard pisolites as organic will doubtless welcome
this egg-like form as a new species. But, as a further illustration of
the eccentricities of concretionary action, I would direct attention to
Fig. 1 of Plate XI, where the shell of a univalve, most probably
a Melanopsis, has been encysted in a number of concentric layers of
brown calcite. A similar concretionary action has taken place
round other specimens of univalve shells, of which sections are given
in Figs. 6 and 8 of the same Plate. This action is interesting from
a lithological point of view, but, as we shall perceive subsequently,
it renders the paleontology more difficult of interpretation.
However, the above instances serve to show that concretionary
action has been rampant in the Creechbarrow Limestone, and it is to
this action that we must ascribe most of the peculiarities of the rock.
In those cases where the pisolitic concretions are numerous and
the limestone is very compact, as shown in Fig. 4, the rock
cuts well and takes a fairly good polish. In this instance the
ground-mass is of a dull cream colour, mottled with buff patches,
and the sections of the pisolites appear in dark brown calcite, which
contrasts well with the non-crystallized matrix. There is much
more variety in the shapes of the pisolites than can be gathered from
the small fragment figured, but they may be classed as quadraie,
circular, and oblong, some showing considerable irregularity of
outline. Whatever may be the shape of these smaller concretionary
bodies, they conform to the conditions already detailed with regard
W. H. Hudleston—Creechbarrow in Purbeck. 199
to the larger ones previously desceibad as the hossadlon form. The
structure is entirely concentric, and this is shown in the flattened
pisolites as well as in the circular ones. Some of these bodies
are seen to be compound, with a very irregular periphery, having
two or more foci of crystallization, and in this way very curious
figures result.
Aw
Fic. 4.—Fragment of the hard pisolitic limestone showing two faces cut at right
angles to each other and polished. | x 14.
Fre. 4a.—Section of one of the pisolites, drawn as a transparency. x 6.
The magnified section of one of the quadrate pisolites (Fig. 4a)
displays some features which are not seen in all the specimens.
For instance, there are two lacunz of clear calcite, which partly
separate the regular annular system of brown calcite from the
ordinary matrix. This is probably due to partial solution of the
matrix subsequent to the formation of the pisolitic concretion We
200 W. H. Hudleston—Creechbarrow in Purbeck.
notice belts of clear calcite also in the annular system, especially
towards the interior, giving the rings an agate-like appearance.
The core, or centre of the pisolite, consists of the matrix partially
modified, but without the brown specks which characterize it. This
appears to be the case in all sections of the pisolites which I have
examined, and suggests that the slight amount of colouring matter,
due to iron oxide, which characterizes the rings of brown calcite,
has been transferred from the included portion of the matrix to the
annular system surrounding it by a sort of centrifugal flow-action,
such as that which forms the ironstone shells of limonitic deposits.
In the case of some of the pisolites the centre consists of clear
crystalline calcite, making the analogy with the ordinary siliceous
agate still more complete.
There remains only one further remark to make in dealing with
these curious pisolites, and that refers to a suggestion that these
concretionary bodies may possibly in the first instance have been
due to Nummulites. Everything tends to refute this supposition,
more especially the association of these pisolitic limestones with
Paludina and Melanopsis. Yet it must be admitted that there is
a considerable resemblance to limestones showing sections of
Nummulites, although the resemblance is apparent rather than real,
as may be seen on closer investigation, and it can be safely affirmed
that nothing approaching organic structure has hitherto been
detected in these pisolites. It is certainly a curious coincidence
that both Nummulites levigatus and N. elegans occur in the Lower
HKocenes of this country, mainly perhaps in the Brackleshams, but
also in the Barton Beds; so that, if the Creechbarrow Limestone had
been of marine origin, there would have been nothing surprising
in the occurrence of Nummulites in any beds of Bagshot or of
approximate age.
Palgontology.—Very little can be said under this head, as the only
specimens of fossils from the Limestone have been derived from the
limited area of the summit pit or the immediate neighbourhood.
There can be no doubt that Paludina is fairly common, as it occurs
both in the form of shells and casts by no means infrequently. The
shells are often obscured by a concretionary investment, as previously
stated, but there is sufficient material to form a fair idea of the
species. It is a form which clearly differs from the ordinary
Purbeck species (P. carinifera and P. elongata), but which has
a fairly good resemblance to the Bembridge species, Paludina lenia,
Solander.?
1 According to Professor Rupert Jones, writing of the physical features of the
Bagshot district in 1880 (Proc. Geol. Assoc., vol. vi, p. 437), ‘‘the Bagshot sands
are the shallow water and western equivalents of the great Nummulitic formation,
which is represented in the east by the thick Nummulite limestones, deposited in the
open ocean of the period.”’
* In my paper in the GzoLocicat Macazine (1902, p. 251), I referred this form
to P. media, Woodw., a synonym of P. lenta, Solander, the latter being the correct
name. The history of P. /enta is rather a singular one. It was first described by
Solander (1766) in Brander’s Foss. Hants, and is regarded as ranging from the
Woolwich (and Reading) Beds to the Hempstead, Bembridge, and Headon Beds.
Hence it is essentially an Eocene and Oligocene species.
W. H. Hudleston—Creechbarrou in Purbeck. 201
No object would be gained by attempting a technical description
of fossils so obscured by incrustation as are these Creechbarrow
_ Gasteropoda, but I must direct the attention of the reader to the
accompanying Plate XI. According to my ideas, Figs. 1 and 5
represent the back and front view respectively of a form which may
possibly be a member of the Melaniadew. The shell shown in
Fig. 1 is enclosed in a series of cysts; the one shown in Fig. 5
appears to me to represent the same species. It is true that the
aperture, in its present condition, gives us very little insight into
the true character of the shell, but this is due to disfiguration from
several causes. Fig. 6 may represent a section of the same species,
and here again the elongate character of the whorls points to some
member of the Melaniadz rather than to Paludina.
In the case of Fig. 9 the aperture has been better preserved, and
few would doubt that this specimen represents a Paludina. It most
resembles P. concinna, Sowerby, which Mr. Bullen Newton (“ British
Oligocene and Eocene Mollusca”) regards as the same as P. lenta.
Although there are plenty of casts in the limestone which one would
refer without hesitation to Paludina, this is the only specimen of
a shell which shows the Paludina mouth with certainty.
Figs. 7 and 8 of the Plate represent specimens (the latter in
section) which have suffered terribly from incrustation, to the
complete obliteration of the true external form; yet I think that in
them we may recognize Melanopsis brevis, Sowerby, described from
the Bembridge series. I have no doubt that a more extended search
would yield a larger series of fossils, since the few specimens of
Gasteropoda which have been figured were derived from a very
limited area, viz. the summit pit.
As regards any other fossils from the Creechbarrow Beds, there is -
a fragment something like Ditrupa in one of the more earthy lime-
stones. A bivalve not unlike a Zucina was also obtained from
a fragment of an ironstone grit found on the surface between
the summit and the eastern spur, but, as I have never seen this
particular bed in sit, too much importance should not be attached
to this ‘ find.’
Conclusion.—The question of the actual age of the Creechbarrow
Limestone is one which I have naturally deferred to the last, in
order that we might be in possession of all the available evidence.
Its approximate age is clear enough as being Lower Tertiary, but
the question now more particularly to be solved is this—Are we to
believe that the Creechbarrow Limestone is really of Lower Bagshot
age and rather low down in the Bagshot series, as appearances
might seem to indicate, or are we to believe that it is of Oligocene
age and a local representative of the Bembridge Limestone? It has
already been admitted that hitherto I have failed to settle this
question from a study of the stratigraphy of the hill, although the
bulging of the Pipeclay series is certainly in favour of the view that
the Creechbarrow Beds do not overlie the Pipeclay series, as must
be the case if they or any portion of them represent the Bembridge
Limestone.
202 W. H. Hudleston—Creechbarrow in Purbeck.
Do we obtain a better clue either from the lithology or the
palzontology of the limestone? I fear not. The two species of
Gasteropoda, which may be regarded as fairly well identified, viz..
Paludina lenta and Melanopsis brevis, are certainly Bembridge
species, but the former occurs in the Woolwich Beds, and we may
well believe that the latter also had a long life as a Lower Tertiary ~
fresh-water species, so that its presence must not be taken as —
indicative of any special horizon. The lithology is equally uncertain.
So far as I am acquainted with museum specimens of the
Bembridge Limestone, it has a somewhat different aspect to that
from near the summit of Creechbarrow, and is, on the whole,
non-pisolitic. Yet there are in the Bembridge Limestone some very
enigmatical bodies. Amongst these are the supposed ‘Cocoons”
referred to by the late Mr. F. E. Edwards as possibly being the eggs
of fresh-water tortoises, or even snails. These bodies are said to
possess no internal structure. Not having any of these ‘Cocoons’
by me at the present moment, I am unable to give any further
description of them, although I strongly suspect that they are not
organic any more than our ‘horseshoe’ pisolites, but most
probably the result of concretionary action. Hence there would
seem to be established a certain degree of. analogy, quad lithology,
between the Bembridge and Creechbarrow Limestones, although this
can scarcely be allowed to outweigh the stratigraphical inferences to
be drawn from the bulging of the Pipeclay series.
Thus, on summing up ail the evidence hitherto available, I rather
incline to the view that the Creechbarrow Limestone and associated
beds are of Lower Bagshot age, yet at the same time I am bound to
admit that it is a point which can only be decided with certainty by
further investigation.
Postscript.—Since the article on Creechbarrow was completed
there are two points on which a certain amount of additional
information has been received.
(1) A deep boring south of Mr. Bond’s brickyard is thought by
Mr. Leonard Pike to indicate the presence of Pipeclay at a considerable
depth within the area hitherto regarded as sterile. If the clays.
in this boring represent the great mass of Pipeclay such as has
been excavated from the ‘Old Clay Pits,’ then the theory that
Creechbarrow bulges the Pipeclay series can scarcely be main-
tained any longer. But if, on the other hand, the material lately
discovered is merely a local manifestation of Pipeclay such as might
occur to a small extent on almost any Bagshot horizon, the recent
discovery cannot be regarded as contravening the general impression
which has hitherto prevailed.
(2) On referring to Edwards’ monograph of the Hocene Mollusca.
(Pal. Soc., 1852), I perceive that he describes with considerable
detail the bodies regarded as the casts of eggs which were found in
the Bembridge Limestone. Those most commonly found, he says,
present a close resemblance both in size and shape to the eggs of
several of the fresh-water tortoises, and may be casts of the eggs of
Geol.Mag 1903. ese Dee. IV. Vol.X.PLXI.
oeeera
SAsninias
G&.Weet lith.
SHELLS & CONCRETIONS FROM
THB CREECHBARROW LIMESTONE.
Dr. A. 8. Woodward—L. Pliocene Bone-bed of Concud. 203:
species of Trionyx or Emys, which lived in the Hocene marshes.
- Others he thought might be casts of some Helicide.
Although we cannot show anything from the Creechbarrow Lime-
stone which exactly corresponds to the supposed eggs from the
Bembridge Limestone, yet a successful reconstruction of the larger
‘horseshoe’ pisolites from Creechbarrow might possibly produce
forms not unlike the ‘eggs’ which attracted the attention of
Mr. Edwards. If this should prove to be the case, there may be
more similarity between the two limestones than has hitherto been
supposed.
EXPLANATION OF PLATE XI.
Fic. 1.—Gasteropod encysted in concretionary layers; P one of the Melaniade. x 1}.
», 2.—Section, approximately horizontal, of the ‘horseshoe’ concretion. Nat. size.
», 3-—Section of the ‘horseshoe’ concretion, drawn so as to show a portion of the:
outer wall. Nat. size.
», 4.—Ege-like body inside the ‘ horseshoe’ concretion. x 3.
», 0.—Gasteropod; ? one of the Melaniade. Front aspect. x 13.
», 6.—Vertical section of Gasteropod, probably the same species as shown in
Figs. land 5. x 14.
», @.—Cf. Melanopsis brevis, Sowerby. Front aspect. x 1}.
», 8.—Section of a similar specimen. x 13.
>, 9.—Paludina ct. lenta, Solander. Front aspect. x 1.
N.B.—Figs. 6 and 8 show the encrusting action to which most of these shells have
been subjected, and which tends to obscure their true character.
IJ].—Tur Lower Putocrnt Bone-pep or Concup, PRovINcCE oF
TERUEL, SPAIN.
By ArntHur Smirx Woopwarp, LL.D., F.R.S., of the British Museum.
(PLATE XII.)
ROM time immemorial a remarkable accumulation of bones in
the province of Teruel, Spain, has attracted attention. It is
especially conspicuous in the low range of hills near Concud, and the
people of that village seem to have generally regarded it as marking an
ancient battlefield. So long ago as 1754 Torrubia briefly described this
deposit in his Spanish Natural History ;' but his curiosity seems to
have been aroused not so much by the bones themselves as by the
erystalline calcite found occupying many of their cavities. ‘Twenty
years later an Englishman, William Bowles, again referred ” to the
same bone-bed, and described it as containing the remains of men
and women mingled with the bones of horses, donkeys, oxen, and
smaller domestic animals. He also observed that the limestone
above the bone-bed was filled with land and fresh-water shells.
Cuvier quoted Bowles’ description in his treatise on fossil bones,’ and
after an examination of some teeth and bone-fragments collected by
Proust at Concud, he was inclined to believe that these fossils really
represented domestic animals as already determined, though he found
1 J. Torrubia: ‘‘ Aparato para la Historia Natural Espafiola’’ (1754); German
edition (1773), p. 68.
2 Guill. Bowles: ‘ Introduccion a la Historia Natural y a la Geografia Fisica de
Espana” (1775), p. 210.
3 G. Cuvier: ‘‘ Recherches sur les Ossemens Fossiles,’’ 4th ed. (1835), vol. vi, p. 427.
204 Dr. Arthur Snuth Woodward—
no associated evidence of man. He suspected that Bowles was
wrong in describing the bone-bed as a regular stratum, and thought
it would probably prove to be a breccia introduced into a fissure in
comparatively modern times.
The true nature and age of the deposit at Concud were first
determined by the researches of De Verneuil, Collomb, and De Loriére,*
who not only made geological observations but also collected fossils
and submitted them to Paul Gervais. In 1853 Gervais perceived
that the supposed teeth of horses and donkeys belonged to the extinet
Hipparion;* and it became evident that the basin of Teruel was
occupied by an Upper Tertiary lake deposit, closely resembling other
lacustrine formations which were then being recognised in various
parts both of Spain and France. ‘Ten years later the province of
Teruel was systematically surveyed by Vilanova, who published
a pioneer geological map and description;* while in 1885 the
province was the subject of a final memoir by Cortazar, issued by
the present Geological Survey of Spain.‘ All these researches
gradnally confirmed the impression that the Concud bone-bed con-
tained the remains of the same Lower Pliocene mammalian fauna as
the well-known deposits of Mt. Léberon, in France, and Pikermi, in
Greece.’
The remote and elevated plain on which Teruel is situated was
made readily accessible last year by the opening of the Aragon
Railway from Sagunto to Calatayud. Being interested in the
Pikermi fauna, I therefore decided in the Autumn to spend a brief
holiday at Concud and make a preliminary inspection of the ground.
Thanks to the kind intervention of A. Frederick Ivens, Esq., British
Vice-Consul in Valencia, and H. Harker, Hsq., British Vice-Consul
in Castellon, I obtained introductions to Senor Don Gregorio Lleo,
Chief of the Forest Department in Teruel,to the Provincial Governor,
and to the Alcalde of Concud. The friendly reception and help
accorded to me by these officers and by the village council of Concud
enabled me to attain my object; and among the villagers themselves
I found both willing guides and workmen. Iam also much indebted
to Mr. Thomas Rees, of the Grao de Valencia, who accompanied
myself and my wife, and contributed to our success by his intimate
knowledge of the Spaniards and their customs.
Concud is about three miles distant from Teruel in a northerly
direction, and the low hills in which the bone-bed is exposed are
nearly two miles further away. These hills are at an elevation of
1 K. P. de Verneuil & E. Collomb, ‘‘ Coup d’Ciil sur la Constitution Géologique
de quelques Provinces de l’Espagne’’: Bull. Soc. Géol. France [2], vol. x (1858),
p- 74.—P. Gervais, ‘‘ Description des Ossements Fossiles de Mammiféres rapportes
Sees par MM. de Verneuil, Collomb, et de Loriére”: ibid., pp. 147-167,
pls. iv—vi.
2 P. Gervais: loc. cit., p. 155, pl. iv, fig. 4.
3 J. Vilanova y Piera: ‘‘ Ensayo de Descripcion Geogndstica de la Provincia de
Teruel”’: Junta General de Estadistica, 1863.
+ D. de Cortazar, ‘‘ Bosquejo Fisico-Geolégico y Minero de la Provincia de Teruel ”’ :
Bol. Com. Mapa Geol. de Espafia, vol. xii (1885), pp. 263-607, with map and
sections.
° A. Gaudry: ‘ Animaux Fossiles et Géologie de 1’ Attique,’’ 1862.
(-zo61 “raqmaydag “prempoony ytUIg mmyyry “Iq Aq pe10jdxq)
‘ureds ‘pnouos ‘seiaAv[ed se] op eouviieg
TIX ‘Id ‘X TOA ‘AI “9G ‘C061 “OVIN “104
The Lower Pliocene Bone-bed of Concud, Spain. 205
about. 3,000 feet above the level of the sea, and capped with irregular
thin beds of limestone. They are so barren as to be scarcely of use
even for the pasturage of sheep, of which poor flocks are kept. At
the time of our visit the red-legged partridge was in season and
very abundant. a]
For a distance of about four miles along the outcrop we continually
found traces of bones and teeth in the talus from the softer beds
immediately beneath the limestones; but the bone-bed itself was
best exposed in the vertical walls of the classical ravine—the Barranca
de las Calaveras, or Valley of Skulls—originally described by
Torrubia and Bowles. We eventually halted here and spent a few
days in extricating the fossils.
The northern wall at the entrance of this small ravine is shown
in the photograpb reproduced in Plate XII. At the top (A) are
observed the overhanging ledges of limestone. Beneath these is
a layer of comparatively soft marl and sand (B) which is filled at most
spots with bones. The lower half of the section then consists of hard
red marl and sandy layers (C), with occasional beds of well-rounded
pebbles, which form prominent ridges on the weathered face. At
this point the bone-bed is inconveniently situated for satisfactory
excavation. We therefore followed it to the head of the ravine,
where the floor rises to its level and makes it comparatively accessible.
At the point where our chief excavation was made, the over-
hanging beds of limestone are from 4 to 6 metres in thickness.
They form irregular layers, some consisting chiefly of the fresh-water
shells described by Vilanova, others composed entirely of chemically
precipitated travertine. The shelly layers contain an occasional
bone or tooth, but no accumulation of mammalian remains. At the
base of the limestone there are traces of lignite and bituminous
marl, also enclosing a few scattered bones and teeth. Next below
is a bed of white marl, about one metre in thickness, almost un-
fossiliferous but with occasional traces of lignite. Then follows
a greenish-yellow, soft, sandy bed, about 50 centimetres thick, with
an admixture of white and greenish marl, sometimes bituminous
at the base. This is the true bone-bed, and immediately below it
occurs the unfossiliferous series of brick-red sandy marls and con-
glomerates so well shown in Plate XII (C).
The bones in the bone-bed do not form an absolutely continuoal
mass, but occur rather in dense patches. They vary in state of
preservation, and at the spot where we worked they were made
fragile by moisture and much distorted by crushing. The specimens
we obtained, indeed, suggest that they had become more or less
rotten even before burial; and I observed no satisfactory evidence
of naturally associated bones—either pieces of limbs or of vertebral
column—such as are common in the bone-beds of Pikermi. The
teeth alone proved to be well preserved, and complete jaws were
often met with. There were no associated pebbles.
The large majority of the remains in the Concud bone-bed Bolone
to Hipparion gracilis. The teeth of this species are especially
common everywhere. There is also evidence of a larger variety
206 Dr. A. S. Woodward—L. Pliocene Bone-bed of Concud.
of Hipparion, which may perhaps belong to a second species. We
found one mandible and one upper jaw of Rhinoceros, with teeth
closely resembling those of R. Schleiermacheri, but not quite identical.
Some decayed fragments of limb-bones and a small piece of a tooth,
not worth preservation, clearly represented Mastodon. A mandibular
ramus, various teeth, and horn-cores are identifiable with Gazella
brevicornis. Other teeth represent an undetermined larger antelope.
Vilanova has also recorded doubtful traces of Cervus and Hyena
eximia,’ while Cortazar mentions the discovery of teeth of Sus.?
A deposit which yields remains of so interesting a mammalian
fauna to the casual work of a few days with a small party of men,
deserves further systematic exploration. It is true that in all the
spots we examined near Concud excavations are rendered difficult
by the mass of overlying limestones, which, in the absence of
timber, need to be supported by pillars of masonry when the marl
and bone-bed are removed. Similar bones, however, have been
noticed in many other parts of the Teruel basin, and it is quite
likely that extended search would lead to the discovery of better
preserved and more readily accessible material.
Such renewed and extended exploration would also be of much
interest from a purely geological point of view, considering the
result of recent researches in some of the so-called Tertiary lake
basins of western North America, and in the remarkable Tarija
Valley in Bolivia. According to Matthew* and Hatcher,’ the
North American deposits in question, with their wonderful bone-beds,
cannot have been formed in great sheets of water, but are partly
wind-borne, partly fluviatile, partly formed in temporary pools.
According to Nordenskjéld,’ the Tarija Valley was once a steppe.
and the remains of Mastodon and other quadrupeds now found
buried there represent animals which lived on the spot and were
engulphed in shifting pools and mud-flats. Hatcher, indeed, con-
siders that similar deposits are now accumulating on some of the
flood-plains in the higher reaches of the great rivers of South
America. Quoting a recent observer, Mr. H. H. Smith, he alludes
to a plain about 400 miles long and in some places 150 miles wide,
which is periodically flooded by the River Paraguay. ‘“‘ Even at
low water at least one-fourth of it is flooded: when the river is
at its highest the whole plain is a vast lake covered with floating
grass and weeds; it is possible to pass almost straight across it
in a canoe, though with great difficulty. Only a few islands
remain here and there; jaguars, deer, and other animals take
refuge on them.”
1 Named Hyenictis greca? by Vilanova, redetermined by Gaudry, ‘‘ Les Ancétres
de nos Animaux,’’ 1888, p. 202.
2 D. de Cortazar: loc. cit., p. 449.
3°W. D. Matthew, ‘‘Is the White River Tertiary an Kolian Formation ?”’ :
Amer. Nat., vol. xxxiii (1899), pp. 403-408.
4 J. B. Hatcher, ‘‘ Origin of the Oligocene and Miocene Deposits of the Great
Plains’’?: Proc. Amer. Phil. Soc., vol. xli (1902), pp. 113-131.
5 KE. Nordenskjéld, ‘‘ Ueber die Siugethier-fossilien im Tarijathal, Sudamerika ”’ :
Bull. Geol. Inst. Upsala, vol. v (1901), pp. 261-266.
E. Greenly—Diffusion of Granite into Schists. 207
Under these circumstances some at least of the skeletons of
drowned animals would be buried in the sediment at the bottom
-of the flood ; while any accumulation of bones lying on the plain
would be rapidly entombed. That great accumulations of this kind
often do occur near water, is indicated by Mr. Hesketh Prichard’s
observations recorded in his recent book on Patagonia.’ On the
bank of one small muddy lake he found a heap of at least 500
skeletons of guanaco, which had perished during the severities of
the previous winter. ‘Their long necks were outstretched, the
rime of weather upon their decaying hides, and their bone-joints
glistening through the wounds made by the beaks of carrion-birds.”’
A desolate plain adjoining Lake Viedma is also described as covered
with the bones of guanaco and other mammals in great profusion.
In fact, in winter the animals seem to congregate near drinking-
places where the water is likely to be free from ice, and there they
die of starvation in immense numbers.
According to an observation communicated to me by Professor
McKenny Hughes, when bones are exposed to the vicissitudes of
ordinary weathering they often disintegrate into sharp flakes.
He has noticed this phenomenon especially in the case of bones
of rabbits scattered on the ground. It is therefore quite likely that
the sharp splinters found mingled with the complete bones in many
of the bone-beds are not the result of any physical violence, but
merely of prolonged exposure to the elements.
IV.—Tue Dirrvusion or GRANITE InTO CRYSTALLINE SCHISTS.
By Epwarp Greeniy, F.G.S.
(PLATE XIII.)
1. Roberts- Austen’s Experiments on the Diffusion of Metals.
BOUT a year ago my friend Professor Dobbie, of the University
College of North Wales, drew my attention to the remarkable
experiments of Sir W. Roberts-Austen (whose premature death we
must lament as a very great loss to science) on the diffusion of solid
metals, suggesting that they might have some geological application.
The phenomena referred to in this paper, in which I have been very
keenly interested ever since my work as a Geological Surveyor in
Hastern Sutherland, occurred to my mind at the time as a probable
ease; but after some reflection certain difficulties began to appear,
and I put the subject aside for awhile. The very suggestive address
of General McMahon to the Geological Section of the British
Association at Belfast has reawakened my interest; and it seems to
me worth while to put forward some considerations on the matter,
somewhat speculative indeed, but which may perhaps be of service
in stimulating research on a fascinating though difficult subject.
Sir W. Roberts-Austen? showed that certain selected substances,
especially gold and lead, were able to diffuse into each other in the
solid state, and at temperatures far below the fusion-point of either.
1 H. H. Prichard: ‘‘ Through the Heart of Patagonia’’ (1902), pp. 189, 203, 254.
2 Roberts-Austen: Bakerian Lecture, Phil. Trans., 1896, vol. elxxxvii; Proc.
Roy. Soc., Oct. 1900, p. 436.
208 E. Greenly—Diffusion of Granite into Schists.
Rods of the metals were placed end to end, and in each case the
gold diffused upwards into the lead.
At the end of four years, at only 18° C. (ordinary Summer
temperature), gold could be detected 9:95 mm. from the contact.
At 251° C., which is still 75° C. below the fusion-point of lead, at the
end of 31 days, ‘002 per cent. of gold was found 7 cm. from the
contact. If the column of lead was kept liquid, the diffusion was
much faster. But as much gold would pass up into liquid lead in
a day as into solid lead at 18° C. in 1000 years.
It is clear, therefore, that in solids, as General McMahon remarks,
as well as in liquids and gases, there is a good deal of molecular
movement; and as we cannot suppose this to be confined to a few
cases only, we may expect diffusion to take place between many
solids under favourable conditions. Any pair of solids cannot, of
course, be expected to diffuse, any more than any pair of liquids—
mercury and water, for example. But solids with as much in
common as most silicate-bearing rocks might reasonably be expected
to do so.
2. The Metamorphic Theory of Igneous Rocks.
Before attempting to apply Roberts-Austen’s results, it will be
desirable to refer to the relation of granites to crystalline schists
in highly metamorphic regions; and, first of all, to review a theory
which at one time had much influence upon geological opinion, and
even now continues to recur from time to time to the mind of
the worker in regions of this description.
The eruptive nature of granite has, ever since the classic
demonstration of Hutton, been rightly regarded as one of the
established truths of geology, and this has been confirmed by
numberless examples since discovered in all parts of the world, and
in rocks of all ages.
But the phenomena to be seen at the margins of granites do not
always show clear evidence of intrusion, and the study of some of
these led to a modification, about the middle of the nineteenth
century, of Hutton’s original view. That granites are often, perhaps
generally, intrusive, was never, I believe, denied. But it was.
asserted that in many cases the margins showed a gradual transition
into the material of the surrounding rocks ; and it was inferred that
these rocks had been in such cases, not merely altered in mineral
character, but actually melted down, and had recrystallized in
cooling as granitoid material; that, in fact, the granite was, in
part at any rate, of metamorphic origin. From this view it was
an easy transition to that according to which such granites were
regarded as of metamorphic origin throughout their whole body ;
the heat to which such fusion was due being then ascribed, not to
intrusion of heated foreign matter, but to local intensification of the
internal heat of the earth. A comprehensive resumé of the theory
is given, with his usual admirable lucidity, by the late Professor
A. H. Green in his “ Physical Geology” (ed. 1882, pp. 399-455).
Unfortunately, however, the theory was not always applied in
this moderate and scientific spirit. The chemical composition of
E. Greenly—Diffusion of Granite into Schists. 209
even the acid igneous rocks always presented difficulties, but basic
rocks and, I believe, even peridotites and serpentines were some-
times supposed to have originated in this way, as well as felsites,
which could not have consolidated under plutonic conditions.
It is easy to be wise after the event, and for one period 6f human
thought to point the finger of scorn at the aberrations of its pre-
decessors ; and we must not forget that at that time hardly anything
was known of the microscopic structure of rocks, and very little
more of their chemical composition.’ When, therefore, in the light
of microscopic and chemical research the field evidence for many
of the alleged cases of transition broke down, it is not surprising
that the whole theory was cast aside, often with no little scorn, and
relegated to the limbo of exploded hypotheses.
The remark has been made by Mr. Herbert Spencer that as there
is ‘‘a soul of goodness in things evil,” so often is there, and that very
generally, “‘a soul of truth in things erroneous.” And in this old
theory there was a soul of truth.
It is noteworthy that most of the cases in which the evidence
so hopelessly broke down were those where the igneous rocks were
surrounded by tracts of ordinary sedimentary rocks that were only
locally, not regionally, metamorphosed. Regionally metamorphosed
rocks had been, indeed, examined, and speculation aroused concerning
them; but the time for systematic research into their phenomena had
not yet come.
The past twenty years or so, however, have seen much energetic
and enthusiastic research into the crystalline schists, and really
scientific methods applied to their problems. Now, during that
period descriptions have been given, from time to time, of a good
many cases where granitoid rocks which occur in districts of
regional metamorphism have been really observed to pass into the
surrounding gneissose rocks by perfectly gradual transitions. North
America, Scandinavia, Saxony, the Alps, more than one part of
the Scottish Highlands, Ireland, and even Anglesey, have furnished
examples.”
1 The time and labour demanded by analyses of silicates have always stood in the
way of a really thorough knowledge of the chemistry of rocks, and at the present
time hardly any work is so much needed in geology, if intelligently directed in con-
junction with microscopic and especially with field work.
2 Lawson: Geol. Rainy Lake Region, 1888, pp. 118, 130, 137.
Van Hise: Pre-Camb. Rocks N. America, Corr. Papers, 1892, p. 488; and, quoting
Jukes, Hitchcock, and others, p. 479.
Reusch: The Bommel and Karm Islands, 1888.
Lehmann: Enst. Altkryst. Sch., pp. 64, 67, etc.
Lory: Etudes Sch. Cryst. : Congres Inter. Geol., 1888.
Bonney: Pres. Address Geol. Soc., 1886, p. 51, ete. ; Two Traverses Cryst. Sch.
Alps, Q.J.G.S., 1889, pp. 95, etc.
Barrow: An Intrusion Muscovite-Biotite Gneiss, etc.: Q.J.G.8., 1893, pp. 341,
343, 353.
Horne & Greenly: Fol. Granites and Cryst. Sch. Kast Sutherland: Q.J.G.S., 1896.
Cole: Metam. Rocks Tyrone and Donegal: Roy. Ivish Ac., xxxi (1900).
Greenly : Sillim. Gneiss, Anglesey: Grou. Mac., 1896, p. 495.
Teall: Pres. Address Geol. Soc., 1902, p. Ixxiv.
(These references are of course not exhaustive.)
DECADE IV.—VOL. X.—NO. VY. 14
210 E. Greenly —Diffusion of Granite into Schists.
3. Gneisses and Granites of Eastern Sutherland.
The phenomena of Hastern Sutherland were described some years
ago in a joint paper by Dr. John Horne and myself. The granites,
which are generally foliated, lie as sills in a region entirely composed
of gneissose rocks in which no original structures whatever have
been detected. On parts of the northern coastline, where granulitic,
somewhat siliceous rocks prevail, the granitoid matter is injected
“lit par lit,” producing complex synthetic banded gneisses. But
on other parts of the coast, and inland about Kinbrace, where a flaky
or wavy biotite gneiss is the dominant type, we find the permeation
phenomena.
In “lit par lit” injection the injecting and the injected rock
retain their separate individualities, however thin and frequent may
be the sills; whereas at the permeation junctions “the margins of
a sill fade off into the gneiss through a series of thinner and thinner
lenticles”’ (Pl. XIII, Fig. 1), “the ends of a sill also fading off
into the gneiss by a dovetailing of biotitic folia into the granite ”
(Pl. XIII, Fig. 2). “‘ Finally, large masses occur in which these
relations are carried to such a degree of intimacy as to render it
very difficult to decide whether to regard them as granite or as
gneiss (Pl. XIII, Fig. 3), difficult even to produce a consistent
map, all lines being wholly arbitrary ” (op. cit., p. 644).?
In the same paper (pp. 642-3) evidence is adduced to show that
much of the gneissose rock so permeated must be of sedimentary
origin. That it does not consist merely of the material of
the adjacent granites altered by marginal shearing is shown by
the existence of uninjured intrusive junctions at other parts of the
same sill (ibid., figs. 2, 3). In conclusion (ibid., pp. 647-8) it was
suggested, though with the caution due to the chemical difficulties
to be encountered, that the granites might not be wholly foreign
matter; and this was ailuded to in the discussion by several speakers,
who pointed out that the suggestion was really a revival of the older
theory which I have described above.
4. Application of Roberts-Austen’s Results.
Now, in the interpretation of phenomena of this kind the results
of Sir W. Roberts-Austen’s experiments seem to open up a prospect
of considerable help. In the permeation zones of these granites,
whatever may be their cause, we see, at any rate, an unquestionable
case of the diffusion of one rock into another.
Roberts-Austen has shown (1) that diffusion takes place between
closely adpressed solids at ordinary temperature, (2) that with rise
On Foliated Granites and their relations to the Crystalline Schists in Eastern
Sutherland ”?: Q.J.G.S., 1896. The views of our colleague, the late Hugh
Miller, jun., are also given in this paper.
2 T had not at the time this was written read this passage from Lehmann (Enst.
Altkryst. Sch., p. 64): ‘‘Die Abgrenzung zwischen dem, was als Granit oder
Graniteneiss und dem, was als Gneisselimmerschiefer zu bezeichnen ware, wird oft
unmiglich und kommt ganz auf subjectives Ermessen hinaus, so schnell wechselt der
Gesammtcharakter,” but cannot refrain from quoting it now. I put one phrase
in italics.
GEOL. MAG. 1903. IDse; IW, Woll; X, Pl, SOU,
Fic. 1.—Side of Granite Sill, Strathy Point.
Nore.—The junctions here shown are much sharper than those of the true permeation phenomena,
the softness of which it is very difficult to represent.
Fic. 2.—End of Granite Sill, Kinbrace.
Fic. 3.—Cliff about 200 feet high, Glas Eilean, Strathy Point.
. 7 ‘
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PF 4
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E. Greenly—Difjusion of Granite into Schists. 211
of temperature diffusion is greatly accelerated, (3) that if the
temperature is kept permanently above the fusion-point of one of
the substances, diffusion is still further accelerated.
It may be asked why there is any necessity to appeal_to these
results, seeing that we have long known that igneous magmas are
intruded in a liquid state, and into remarkably narrow veins. But
if ordinary igneous intrusion can account for all the phenomena
under consideration, why do we not find permeation zones surrounding
all intrusive rocks, even ordinary basalt dykes, for there is reason
to believe that basic magmas have a high degree of liquidity ?
On the other hand, it is clear that solid diffusion does not take
place between rocks by mere close adpression, even after long periods
of time, for junctions of normal igneous, even plutonic masses with
sedimentary rocks of all ages, as well as junctions of igneous and
sedimentary rocks with one another, can be seen at which no
permeation whatever has taken place. Rocks do not, it is evident,
diffuse with the ease that gold and lead do.
It is clear that another factor must be necessary, and this can be
found, I believe, in the existence of an already high temperature in the
surrounding rocks.
Ordinary igneous intrusions, as is shown by their chilled edges,
found the rocks into which they were injected relatively cold, i.e., not
appreciably above the temperature proper to a zone of the earth-
erust far outside that from which the magma came. They cooled,
therefore, at the margin soon after injection, and did not remain in
contact at a high temperature for any length of time.
But there is abundant evidence in permeation regions that the
granite at the time of injection found the surrounding rocks already
at a high temperature. The junctions in Eastern Sutherland are
clearly exposed in a great many places; and yet no sign of a chilled
margin has been detected anywhere. The same is the case in other
regions. (Indeed, “lit par lit’ injection itself would appear,
a priori, to be possible only among hot rocks, as seams so thin would
soon consolidate among cold rocks, and so fail to make their way for
any distance.)
If, now, we suppose a granitic magma introduced among rocks with
a pre-existing temperature scarcely lower than its own (it might be
even higher if the rocks were less fusible), not only would much
more intimate intrusion be possible, but even when actual intrusion
ceased the granite sills and the adjacent rocks would retain a high
temperature at the junction for a very long time. The conditions,
in fact, would be related to those of ordinary intrusion somewhat as
those of a column of liquid lead poured into a hot cylinder on to hot
gold would be to those of lead poured into a cold cylinder on to cold
gold. Solidification would be long delayed, and all this time the
magma might reasonably be expected to diffuse into the surrounding
rocks, following their natural divisional planes, and giving rise to
all the phenomena of a permeation zone.
The singular fact that the inclusions of gneiss in granite, even down
to the thinnest films, are so very seldom, in these zones, disturbed in
212 A. R. Hunt—Vein- Quarts and Sands.
position (ibid., fig. 4), affords some support for the view that the
extension of the magma proceeded by quiet diffusion rather than by
forcible injection.
An explanation would also be found for the occurrence of lenticles
of granite in complete isolation from the parent mass.
The experiments quoted lead us to expect that diffusion might
go on even after solidification, seeing that in such a complex a high
temperature would be maintained for a long time, thus extending
the permeation zone yet further, and in perhaps an even subtler
manner. Indeed, what we know of the changes that have certainly
gone on in solid rocks shows that the solid state is no obstacle to
extensive molecular change.’
The principal difficulty would be this. The solids of the ex-
periments were homogeneous, being pure metals, so that diffusion took
place between molecules of only one kind on either side. Whether
the liquid magma of a granite was a completely homogeneous
liquid we do not know, but certainly after solidification no granite
is a homogeneous solid. Molecules of at least three kinds would
therefore, it would appear, have to diffuse in order to convey
granitoid matter from place to place, and that in due proportion.
This is certainly a difficulty, though not an impossibility.
Moreover, are we quite sure that solid diffusion would be obliged
to proceed in this way? At the close of the paper by Mr. Horne
and myself to which reference has been made, it was pointed out
(ibid., pp. 647-8) how little is known of the chemistry of the
compounds of silicon, and how very much may be hoped for from
an extension of that knowledge, when we consider the chemical
analogies presented by that element and the part which it plays
in Nature.’
V. — VEIN-QuartTz AND Sanps.
By A. R. Hunt, M.A., F.G.S.
(OME time ago my friend Mr. Jukes-Browne asked me to examine
some sand, with a view to ascertaining whether it was derived
from Dartmoor. Dartmoor quartzes have so many specific characters
that it is often easy to say that a quartz is not derived from that
region ; but owing to the fact that quartz-veins have not been studied,
it is usually impossible to say whence various sands have in fact come.
In the course of conversation, Mr. Jukes-Browne suggested my
submitting a short letter to the GroLocicaL MaGazrng, as the subject
might interest students; but the more I looked at the matter the
more abstruse and cumbrous did it appear; and, from past experience,
I doubted whether the inquiry would not be more attractive to chemists
than to geologists.’
1 Hitherto we have been under the necessity of invoking the agency of percolating
water.
2 My friend Dr. Horne very kindly read the MS. of this paper, and he gives me
leave to say that he agrees with the views expressed in it. Indeed, I believe it would
be nearer the truth to say that he had come to similar conclusions defore he saw my
MS., and had discussed them with my former colleagues of the Scottish Geological
Survey.
3 [ was unaware at the time that quartz-veins were under discussion in the Magazine..
A. R. Hunt—Vein- Quartz and Sands. 213
In December, 1886, when examining marine sands, I pulverized
a flint pebble and several quartz-pebbles for the sake of comparison
in the microscope. I noted that the first quartz-pebble I examined
was full of enclosures with bubbles. Subsequently I had_more than
a dozen vein-quartzes sliced. Not only did they all contain bubbles, but
they all contained moving bubbles, the infallible proof of the presence
of fluid. Quartz-veins and granites are near of kin, and in 1889 I wrote
a paper on granite. My interest in sands and granites led me to
appeal more than once to the most distinguished honorary member
of our local Society, Dr. H. C. Sorby, F.R.S., who was most unsparing
in his assistance in both of those subjects, which he had so long made
his own. However, as might be expected, the nut proved too hard
for me to crack. But Dr. Sorby’s old correspondence has now put
me into no slight dilemma. I cannot publish it, and I can scarcely
absorb the ideas and dispense them as my own; while the last thing
I should care to do would be to appear in the slightest degree to sit
in judgment on the master. Yet the only points which interest me
are those in which I do not quite understand Dr. Sorby; the fault
being no doubt my own, if only for not having sought an explanation
direct.
One point which has caused me much thought in the matter of
sands is the omission by Dr. Sorby of all mention of quartz-veins
as one derivation of quartz-sands, both in the addresses to the
Microscopical and Geological Societies. The same doubt arises in
the case of M. Delesse and the beaches of the French coast. We
hear much of hyaline quartz-sand, but nothing of vein-quartzes ;
yet vein-quartz seems an important constituent of grits and sandstones.
There are, moreover, many quartz-veins the sands derived from which
could not be distinguished from sands derived from granites, seeing
that water inclusions, carbonic acid inclusions, chlorides, and negative
crystals are found in both varieties. We need not flatter ourselves
that we can distinguish a granite quartz by its clearness and freedom
from opacity. Rock crystal is the clearest of quartz, and it is no
rare thing to find water-clear crystals and milky crystals lying side
by side in the same drusy cavity; while between the two there may
be found elsewhere every gradation. When once we begin to reflect
on the whys and the wherefores of quartzes, we soon find ourselves
across the borders of the known, and I feel inclined to transfer to
quartz an observation by Dr. Sorby on granite, viz., that there
are many things connected with it about which we know much less
than is desirable.
I believe that the most important paper on the subject is still
Dr. Sorby’s short address of four pages to the Microscopical Society
in 1876, “On the Critical Point in the Consolidation of Granitic Rocks.”
So far as Lam aware, there are only two points in that paper that
have been reconsidered, and neither of them are of material importance,
so far as regards vein-quartz. Dr. Sorby followed Cagniard de la
Tour in taking 412 C. as the critical temperature of water, whereas
Mr. Hartley, in the Report to the British Association in 1877, treats
it as being 842°C. Dr. Sorby also assumed that above the critical
214 A. R. Hunt—Vein- Quarts and Sands.
temperature water-vapour would cease to act as a solvent, whereas
according to subsequent experiments it appears to do so.!. This, of
course, is a most important point as regards the consolidation of
minerals other than quartz; but fortunately all the authorities appear
to agree that the quartzes of granites consolidated under 342°; and
probably no one would maintain that the quartzes of veins represent
a temperature as great as that of granitoid rocks. [If all this be true,
the question of vein-quartzes is very much simplified. Liquid water
will dissolve a variety of minerals which water-vapour under 342° C.
will reject and deposit. With water-vapour over 342°C. we need
not ex hypothest concern ourselves—fortunately for the length of
this paper.
Writing of the variation in the proportional contents of cavities,
Dr. Sorby has this very weighty passage, viz.: ‘‘The very great
variation in the relative amount of water and liquid carbonic acid in
the cavities clearly proves that very great changes in the surrounding
circumstances sometimes took place, even during the growth of one
single crystal; and there is good reason to suspect that there may
often have been considerable variations in temperature and pressure,
as well as in the relative amount of water and gas ” (‘Critical Point,”
ete., R. Micr. Soc., 1876). In 1889 and 1890 I wrote two papers
on the granite question, and Dr. Sorby, when acknowledging receipt
of one or other of them, remarked, “I very much agree with what
you have said in your paper, and it now seems to me that the
conditions when granite was consolidated were very complex in
some cases, even more so than I urged in my paper.” This view
has been wonderfully confirmed by the rock 'Trowlesworthite, which
indicates fluoric, boracic, and phosphoric acids, a regular jumble of
water and brine, and two tourmalines, one probably above and one
certainly below the critical temperature of water.
With respect to the evidence borne by cavities that the temperature
was over 342°C., we may cite Mr. Hartley :—“ In a colourless and
clear topaz there were discovered thousands of perfectly cylindrical
tube-like cavities, round at each end. In the case of fifty-two
cavities . . . . they each contained the same proportions of carbonic
acid liquid, carbonic acid gas, and water. Hence at the time they
were enclosed in the mineral, these fluids must have existed in the
state of a homogeneous vapour. This of necessity places the
temperature of formation of the mineral somewhere above 342° C.,
the critical point of water” (Rep. Brit. Assoc., 1877, p. 236).
The general conclusion seems to be as follows :—
Fluid inclusions with deposited crystals are clear proof that the
fluid was entangled in the quartz or other mineral, under 342° C.
Water inclusions with variable proportions of water and vacuity
were also formed under 342° C.
Groups of inclusions with proportionate amounts of water and
liquid carbonic acid prove a temperature exceeding 342° C.; but with
disproportionate amounts of water and acid they indicate a tem-
perature below 342° C.
1 J. B. Hannay: Proc. R.S., 1881, p. 321.
A. R. Hunt—Vein- Quarts and Sands. 215
Groups of water inclusions with proportionate amounts of water
and vacuity may indicate a temperature over 342°C. ; or unchanged
conditions of heat and pressure during the crystallization of the
including mineral, under 342°C. Pure water would suggest the
first, while the presence of brine or dissolved salts would-prove the
second. A paper read by me at the Belfast Meeting of the British
Association was founded on the idea of the heating of a district in
the presence of water, with the result of forming hydrous minerals,
and fluid inclusions in the altered rocks. But this was only a variant
of a forgotten warning of Dr. Sorby twelve years before, viz. : “‘ There
is a point which should not be overlooked (1 forget whether I alluded
to it in my paper), and this is, that a rock formed under one set of
conditions may have been exposed to others, and thus the state of
the cavities may indicate the change produced by a reheating of
rock.” This seems to lead to a curious possibility, viz., that a crystal
of quartz might catch up fluid with various salts in solution, such as
soda, potash, and magnesia, and that on a strong reheating of the
crystal the said minerals might enter into combination with the silica
and form microlites. It is not uncommon to see a fissure in a crystal
cemented with a brown iron oxide, which, if hydrous, would account
for a good deal of water.
My collection of slices of vein-quartz is too small for any useful
purpose except to indicate possibilities ; but, so far as the slides go,
they are very instructive. Specimens collected between Dartmouth
and the Start contain one or more of such minerals as chlorite, epidote,
fibrous hornblende, and triclinic felspar. Then on Dartmoor and
its borders specimens of rock may be found showing every gradation
from the simple quartz-vein, through veins composed of quartz-
tourmaline and quartz-tourmaline-felspar (triclinic), to the quartz-
felspar-tourmaline rock of normal granitic structure. In all these
rocks the varying proportions of water and vacuity, and, above all,
the ubiquitous presence of dissolved salts, indicate a temperature well
under 342°C. One very eccentric slice from a vein in a greenstone
presents the appearance of a typical satiny quartz, but under the
microscope it is seen to contain innumerable water inclusions and
carbonic acid inclusions. It also contains a small crystal of plagio-
clase, and exhibits throughout the curved shadows of a felspar.
Observing that there seemed two varieties of quartz-veins near the
Bolt Head, I ascertained that one was very full of fluid inclusions
and the other unusually free from them. Possibly one represents the
era of metamorphosis, and the other may be either older or later.
So far as I can ascertain, no one has worked the vein-quartz
problem, or at any rate has published the results. Dr. Sorby showed
in his first paper that the inclusions in quartz-veins in the neigh-
bourhood of granites were intimately connected with the inclusions
in the granitic quartzes themselves, but I am not aware that he has
anywhere described the differences between quartz-veins of different
ages and which have been subjected to different conditions. Nearly
all my quartz slides are post-Devonian, and possibly post-Carbon-
iferous, and they differ greatly from the quartzes in Culm grits and
216 Beeby Thompson— Use of a Geological Datum.
conglomerates, and from a conglomeratic grit which, according to
Mr. E. B. Tawney, is either Cambrian or Archean. The latter is
emarkable for the uniform minuteness of the fluid inclusions, and
or the almost universal activity of the bubbles. For all I can see,
I cannot doubt that a careful study of quartzes of different ages
would furnish much useful information, bearing both on the age and
origin of sands and on the origin of crystalline rocks.
There are at present so many well-trained petrologists that perhaps
it is not too much to hope that some young aspirant to fame will
secure a small grant for expenses, collect quartz-veins of every
obtainable age, and exhaust all the information that can be squeezed
out of them. The most important papers on the subject after
Dr. Sorby’s classic paper in the Q.J.G.S. of 1858 are the same author’s
address to the Microscopical Society in 1876, and Mr. Hartley’s
papers on fluid inclusions to the Royal and Chemical Societies and
his Report to the British Association in 1876 and 1877. Perhaps
the chief thing to bear in mind as a spur to attack these much
shirked problems is Dr. Sorby’s final word, viz., ‘there are many
things connected with [the subject] about which we know much less
than is desirable.”
VI.—TuE wseE oF a GeonogicaL Datum.
By Brrsy Tuompson, F.G.S., F.C.S8.
PROPER interpretation of some geological phenomena requires
that allowance shall be made for differential earth-movements
that have taken place since the period of occurrence of the events
or conditions under consideration.
Present differences of level in rocks of the same age may be
partly due to actual differences in depth of the sea-floor on which
they were deposited, but they may also be the results of subsequent
differential earth-movements either of a regional or of a local
character, the latter including ‘< faults.’
In order to estimate the amount of displacement or differential
movement, it is necessary to select a particular rock as a datum.
The rock selected should combine, as far as possible, the following
characteristics :—
1. It should be comparatively thin.
2. It should have a considerable horizontal extension.
3. It should combine similarity in physical characters and
paleontological contents over a large area, so that uniformity of
depth of deposit may be postulated.
In the district with which I am best acquainted, Northampton-
shire, either of three formations would fairly well meet the
requirements named above for certain purposes, viz., the Rheetic
Beds, the Marlstone Rock-bed, and the Cornbrash. For a particular
object I selected the Marlstone Rock-bed as the most suitable datum,
and the results obtained by its use in this manner are, I think,
sufficiently interesting to record, since they appear to justify the
selection and the method of use.
Beeby Thompson— Use of a Geological Datum. 217
It is fairly well known that one deep shaft and four deep borings
have been made within Northamptonshire, two in search for coal
and three for water.!. The best readily available account of these
is contained in a paper by the late Mr. H. J. Eunson, published by
the Geological Society.”
Below is given an abbreviated and rearranged account of these
five sections in accordance with information contained in the paper
above referred to, together with certain corrections which it is the
partial object of this paper to justify.
Summary or Derr Borines In NORTHAMPTONSHIRE.
Distance in feet above or below Ordnance Datwn.
ate | eas :
, 6 |28|2¢|8¢
Name of Formation, etc. A Sle = | ST SP || Sos 2s
8 | 842 |/S35|e3 |ee2] g
6 |A4H” |44 |HLl|H~—!] ©
‘Surface of the ground +282} +191 | +278) +374| +374| +374
‘Top of the Middle Lias +274 nee +107 | +164] +108] +326
‘Top of the Rheetic Beds (White Lias) —299| —405 oe ae ... | —292
Top of the Trias CS Littoral
Beds) — 335 ig — 460 | —486 | —486 | —314
fold Tamdlsuntbes.. —417| —455 2 |—5273|( Pee Perl — sa
—593)—593
Top of the Carboniferous Formation | —417| —456 ? |—5273
Top of the Old Red Sandstone? ... | —607
‘Top of the Archean Rocks ane ae Bs BC .. |—341
Bottom of section .. 36 —712|} —459 —573| —593| —593} —415
Thickness in feet.
Superficial deposits 7 26 4 10
‘Oolitic Beds ds ah Hes 14 206 | 266
Upper Lias 1 aa 153 38
Middle and Lower Lias ... 573 570 567 | 654 | 594 | 618
Rheetic (including Littoral Beds of
Rheetic age)... 36 ) 22
Trias (including Littoral Beds of 50 67% .| 107 | 107
Triassic age)... 82 ) 27
Lower Carboniferous Rocks 190 4 454
Old Red Sandstone ? 105
Archzean (volcanic rock) ... FS 74
Total thickness 994 | 650 | 851 | 967 | 967 | 789
In the preceding Summary of Borings I have grouped various
beds together where there might be a difference of opinion as to
their
objects of this paper.
individual limits, and where so doing
For instance, in three of the sections —
1 For convenience we will speak of all as borings.
* Henry John Eunson, F.G.S.,
Northampton ”’
: Quart. Journ. Geol. Soc.,
does not affect the
‘The Range of the Paleozoic Rocks beneath
vol. “xl, pt. 3, No. 159, pp. 482-496.
218 Beeby Thompson—Use of a Geological Datum.
Gayton; Northampton, Bridge Street ; and Northampton, Kettering
Road—the Middle Lias is described in Mr. Eunson’s paper as
“Middle Lias (rock-beds),” and the thicknesses are given as
20, 20, and 21 feet respectively; all below, for some 550 feet,
coming under the title Lower Lias Clay. No doubt, actually, the
Middle Lias, that is to say, all beds between the ‘Capricornus ’
zone below and the ‘Serpentinus’ zone above, is close upon
100 feet thick, but no information is available to fix the lower
limit precisely in any of the borings.
The Littoral Beds are of somewhat different ages in the different
places, but have been grouped with the Trias or the Rhetic for
convenience.
Firstly, on reference to the Summary of Borings in Northampton-
shire, it may be observed that whilst the Old Land Surface now
varies in height by more than 252 feet, the variation in thickness
of the rocks between it and the top of the Middle Lias only reaches
663 feet plus so much more as would require adding on to the
252 feet also.
Secondly, it will be noticed that the Old Land Surface is lowest
where the Rhetic beds have not been detected, which appears
rather singular. Mr. Eunson observed this, and made the following
remark thereon (p. 494): . . . but the Kettering-road boring
shows a great depression. This may partly account for the absence
of the White Lias and Rheetic, and the sandy appearance and
uneven bedding which the lower part of the Lias Clay presented
in this boring, and which was not noticed at either Orton or
Gayton.”
My inability to understand in what way a quite local depression
could lead to an entire absence of certain characteristic marine beds
developed to a thickness of 36 feet within about five miles (Gayton),
and to sandy conditions of the Lower Lias, led me to make the
following simple calculations. Assuming that the well-marked
Marlstone rock-bed was deposited under uniform conditions as to
depth within the area under consideration, and taking it as a datum,
then, according to the figures quoted in the Table of Borings,
relatively to Northampton, Gayton has since been raised 167 feet
and Orton 219 feet. A correction made on this basis altogether
changes the appearance of things. The Old Land Surface at
Northampton, instead of being 1103 feet lower than at Gayton and
1863 feet lower than at Orton, becomes 563 feet and 323 feet higher
than at these places respectively. The following table will
graphically show this.
Of course, in an argument of the nature here presented, it is
impossible to say how much of the difference of level is due to
upward movement of one place, and how much to depression of
another with which it is compared; therefore the selection of a
section for reference is arbitrary. Having selected the Kettering
Road boring, Northampton, we will make a few comparisons
between this and each of the others, together with some observa-
tions arising out of them.
Beeby Thompson—Use of a Geological Datum. 219:
TABLE SHOWING VARIATIONS OF LEVEL DUE TO HKartTH-MovEMENTs.
Height from Ordnance Datum in feet.
eee: Northampton.| Orton.
F326
Present actual levels: top of Middle Lias +274
SI 407
— 341
3 oF Old Land Surface —417 VA
NP 5272
Restored relative levels: top of Middle Lias +107 +107 +107
—5274
es ap Old Land Surface — 560
— 584
Sao Sar Rheetic Beds, No Rhetic Beds,
Significant records... Bir f { 36 feet. hess Teale. 29, feet.
Gayton. —After having made our correction for earth-movements
subsequent to the Middle Lias period, if we pile the 82 feet of Trias
and Littoral Beds on to the Old Land Surface at Gayton, and the
67% feet of similar beds on to it at Northampton, it will still leave
Northampton 42 feet the higher, an amount of difference in level
sufficient to entirely exclude the 36 feet of normal Rhetics found
at Gayton only about five miles away, in strict accordance with
our specification of a datum rock, though very probably the upper
portion of the Littoral Beds at the Kettering Road are of Rheetic age.
The addition of 36 feet of Rheetic beds at Gayton would, however,
bring the levels of the two localities, Gayton and Northampton,
within 6 feet, consequently this is the amount of difference in
ageregate thickness of the Middle and Lower Lias at the two places
(see Table). A very small amount, it will be observed, out of
570 feet, considering that the places are about 5 miles apart.
Northampton (Kettering Road).—It follows from the above con-
siderations that the Littoral Beds at the Kettering Road boring,
Northampton, may be of an age extending from the Triassic, through
the Rheetic, even into the Lower Liassic periods. This will help
to explain the abnormal character of the deposits themselves, and
also the sandy nature of the lower beds of the Lower Lias there,
for, no doubt, land remained exposed and the sea shallow to a still
later period than at Northampton, not far away.
Northampton (London and North-Western Railway, Bridge Street
Station).—The account of this boring left by the Rev. C. H. Harts-
horne' runs as follows :— feet.
Superficial accumulation, consisting of detrital gravels, dark
tenacious clays with erratic boulders... hs 300 ooo) 448
Lias blue clay with bands of stone eS 600 oe aon OUI)
Very hard pyritous rock 1
Variegated sandstone (viz., red, green, and white), with 15 feet
of limestone Rae sae nee wae sae Pe N= 46
White sands ae ae ae Bae 33: ink 3
Magnesian limestone _ oh BBE hee Ji3 sce shi 4
Total ats ok Son as sco BOO)
1 Rey. C. H. Hartshorne: ‘‘ A Report on the Drainage of the Nene Valley”’
Northampton, 1848.
220 Beeby Thompson— Use of a Geological Datum.
Salt water came from the bottom of the boring and rose to within
8 feet of the surface.
This boring is situated about two miles from the Kettering Road
boring, and in a nearly direct line between the latter and Gayton
boring. It is on the south side of the Nene ‘fault,’ and not far
removed from it; also, notwithstanding that the Marlstone rock-bed
is not present, or at least was not recognized, I am convinced that
the Middle Lias is nearly complete, the upper part being represented
by what is described above as “dark tenacious clays with erratic
boulders ” to the extent of about 20 feet out of the 46 feet. ‘This
belief is founded on personal inspection of material brought up
from a well on the same side of the Nene ‘fault,’ starting at
approximately the same level above O.D. and only about a quarter
of a mile away to the north, at Messrs. Phipps’ Brewery, and from
the fact that at two places a little nearer the line of the river Nene
alluvium and gravel combined had the thickness of 27 feet and _
28 feet respectively.
Referring again to the same section, when it became evident that
the combined thickness of Middle and Lower Lias was nearly
identical with the thickness of the same formations at Gayton
(see Summary of Borings), then also it became highly probable
that the very hard pyritous rock, 1 foot thick, immediately under
the Lower Lias was the equivalent of the hard white limestone with
pyrites, 1 foot thick, similarly situated at Gayton,’ both, in fact,
constituting the top of the White Lias.
Levelling each of these rocks to a Marlstone datum of + 107 feet
0.D., as in previous instances, we get the Gayton hard limestone
coming out as —466 O.D., and the Northampton, Bridge Street,
hard pyritous rock as —463, or a few feet below this if we make
allowance for the slight imperfection of the Middle Lias there.
Anyway it is obvious that these rocks were deposited at practically
the same depth at the same time. Thus the Rhetic beds are
virtually brought into Northampton, and the suggested cause of
their absence in normal form two miles away, at the Kettering Road
boring, is made a certainty.
Orton.—After correcting for the post-Liassic earth-movements
(p. 218), and placing on to the Old Land Surface at Gayton
118 feet, and at Orton 49 feet (aggregate of Trias, Littoral Beds,
and Rheetics), then the top of the Rhetic beds at Orton would
be 45 feet lower than at Gayton; and it might be asked why, in
accordance with the gist of this paper, the whole of the Rhetics
are not present at Orton, or inversely why any whatever are present
at Gayton. I cannot here deal with the whole subject involved
in an answer to such a question, but chiefly and briefly my reply
is this:—Orton, at the close of the land period, was higher than
Gayton (smaller thickness of Trias and Littoral Beds); at the
latter end of the Rhetic period at about the same level (indis-
tinguishable nature of some of the deposits from the two places) ;
1 Henry John Eunson, F.G.8., ‘‘The Range of the Paleeozoic Rocks beneath
Northampton’’: Quart. Journ. Geol. Soc., vol. xl, pt. 3, No. 159, p. 486.
Beeby Thompson— Use of a Geological Datum. 22h
in Lower Lias times lower (greater combined thickness of Middle
and Lower Lias), because it, i.e. Orton, lay further to the north-
west of that line or direction about which, as a fulcrum, a general
north-westerly sinking was taking place at the time under con-
sideration, than either Gayton or Northampton. Wear
The almost identical thickness of combined Lower and Middle
Lias at Gayton and Northampton would lead us to judge that these
places were actually on the line of fulcrum, or one parallel to it,
and since they are almost accurately south-west and north-east
of each other respectively, that direction may be looked upon as
the general direction of the axis of movement.’
Kingsthorpe.—The shaft at Kingsthorpe was made in a search
for coal, in 1836. According to the late Mr. S. Sharp, F.G.S.,? “No
accurate detailed section of the shaft was taken at the time; but
at a depth of 210 feet from the surface, a water-yielding ‘limestone
rock’ in the Middle Lias (Marlstone) was pierced, which produced
36,000 gallons of water per hour. At a depth of 880 feet (as is
stated in pencil notes on a diagram in my possession, which notes
‘are said to have been made by Dr. William Smith, ‘the Father
of English Geology’) the New Red Sandstone was reached, and
a flow of brackish water of a like volume to the former occurred.”
It is quite certain that the above description of the Kingsthorpe
shaft is in error somewhere, for, taking the figures as they are
given, (a) of the 210 feet down to and through the rock-bed of the
Middle Lias, the Upper Lias would absorb 180 feet or more, leaving
less than 80 feet for all beds between it and the Great Oolite Lime-
stone, whereas in the near neighbourhood they are considerably
more than twice this thickness; (6) the top of the Middle Lias
appears as 57 feet higher than at the Kettering Road boring; (c) the
Middle and Lower Lias have an aggregate thickness of 654 feet
compared with 567 on the Kettering Road, a difference of 87 feet in
just over a mile.
Applying the Marlstone datum to Kingsthorpe, the results come
out as below. Take + 107 feet O.D. as the top of the Marlstone
rock-bed at Kingsthorpe, the same as at the Kettering Road boring
quite near, and we get 267 feet (374 — 107) as its depth; give the
rock a thickness of 4 feet, and it is evident that it would be pierced
at 271 feet from the surface. In 1881 the Kingsthorpe shaft was
opened up by my advice, to see if it were yielding any water from
the Marlstone at 210 feet or thereabouts ; it was not, but salt water
filled the shaft to within 270 feet of the surface exactly. Putting
these two items together, the inference is very forcibly driven home
that someone has mistaken 270 for 210 in reading the records of the
shaft, a thing very likely to happen.
Personally, I have no doubt that the error suggested above
occurred, because, after making the correction, the general accuracy
' See also ‘*The Victoria History of the Counties of England: Northampton-
shire,’’ Geology, vol. i, p. 8.
2 “Note on a futile search for Coal near Northampton ’’: Grou. Mac., Vol. VIII,
p- 505.
222 Beeby Thompson— Use of a Geological Datum.
of the original record of the Kingsthorpe shaft becomes very
probable; all difficulties of interpretation are removed; and we
can give to the various formations their necessary thicknesses and
reasonable positions above O.D.
The fact that in 1881 salt water filled the Kingsthorpe shaft to
within 270 feet of the surface is suggestive ; it would indicate that
the Marlstone rock-bed then determined the height to which the
water could rise, and, therefore, that salt water was then feeding
the Marlstone to some extent; indeed, it is almost certain that,
according to the amount of pumping going on at Northampton,
the Kingsthorpe shaft may feed or be fed by Marlstone water. |
Fortunately, the supply of salt water is very moderate, and the
greatest variation in chlorine I have observed in the Marlstone
water is 1:61 grains per gallon. In 1879, when Marlstone water
was used almost exclusively for the town supply, the water yielded
5:6 grains of chlorine and 50:5 grains of solid matter per gallon;
in 1897, when it was used intermittently, the chlorine came out
as 3:99 grains per gallon, and solid matter 48.
Before giving a revised section of the Kingsthorpe shaft, I must
justify another alteration to be made in the figures, ete. The Mining
Journal of September 3rd, 1854, in a description of the Kingsthorpe
undertaking, after giving an unintelligible classification of the beds
above, says that the Lias formation “‘was followed by 84 feet of
New Red Sandstone, 13 feet of Red Marl, and 15 feet of Con-
glomerate.” This description was quoted in the 1854 prospectus
of “The Northampton Great Central Coal Mining Company.”
Mr. Sharp, in one place, says’ that the blue clay of the Lower Lias
was pierced at 860 feet, and is stated to have been succeeded by
80 feet of Sandstone, 12 feet of Red Marl, and 15 feet of Con-
glomerate; in another’ he says that at 880 feet the New Red Sand-
stone was reached. My opinion is that all three descriptions are
essentially correct, and that the difference of 20 to 24 feet of beds,
which the geologists could not decide what to call, is the equivalent
of the Littoral Beds, 27 feet thick, above the Trias at the Kettering
Road boring, about which, and other beds below, Mr. Etheridge
said, ‘“‘no equivalents in Britain,” ‘no series like them” (Kunson,
p. 484). That these undefined beds at Kingsthorpe contained
conglomerates is evident, for in Miss Baker’s collection of fossils
was a specimen of conglomerate consisting of limestone pebbles
in a greenish, sandy, and highly calcareous matrix, some parts
hard and crystalline, labelled “Top of Red Sandstone upwards of
900 feet, Kingsthorpe shaft,” a label which until recently I could
not understand.
In the revised section given below, the Upper Estuarine Beds,
Lower Hstuarine Beds, and Ironstone Beds (not all ironstone,
1 “The Oolites of Northamptonshire,’’? part i: Quart. Journ. Geol. Soc.,
March, 1870.
2 «Note on a futile search for Coal near Northampton’’: Grou. Mac., Vol. VIT1
(1871), p. 505.
J. R. Dakyns—Milistone Grit of Grassington. 223
however) are given to the nearest foot from the record of a well
recently made (1902) just over one mile away to the east.
F : _ | Depth of |Height of
Old Section. Tueine ee Revised Section. Te “S| base | top from
he oe Een iiee|p ni teets | OnD.
Rocks down Superficial Beds... ... 8? 5s +374
to and } Upper Estuarine Beds... 26
through the 210 Lower Estuarine Beds.. 3l
Rock-bed of . Ironstone Beds Gate to
the 18 BH UE) sco oc 21 86?
Middle Lias Wyaper IOMER coo con con 180 ? 266? +288 P
: Middle Lias... ... 100? 366? | +108?
Ses aug an 650 Lower Lias, with stone
bands towards the base 494 P 860 +8
( Littoral Beds, including eg
Sandstone ... 80 conglomerates... ... 20 880 —486
( Red Sandstone ... ... 60 940 —506
Red Marl ... 12 vel Wien: | S595 bod. Soc 12 952 — 566
‘Conglomerate 15 Conglomerate ... ... 15 967 —578
967 Total depth ... 967
In conclusion, it may be pointed out that, beyond the direct
object of the paper, several little points in local geology have been
cleared up or made more intelligible. Perhaps the most generally
useful result is the demonstration that a levelling up process was
going on just before the commencement of the Lower Liassic
period, which culminated in the Rhetic beds (White Lias), and
that a similar levelling took place at the close of the Middle Lias
period, though this was perhaps as much a result of redistribution
of material in shallow water, a give and take process, which
ultimately led to the very uniform conditions of the ‘ Acutus’ zone
(Transition bed) at the top of the rock-bed of the Middle Lias.
VII.—Nore on tHe Mittstone Grits oF Grassincton Moor.
By J. R. Daxyns.
HE Millstone Grits of Grassington consist, speaking generally, of
the beds given in the following table, viz. :—
Grit of Henstone Band.
Measures.
Thin limestone.
Redscar Grit.
Measures.
Sandstone.
Measures.
Sandstone of Priest Tarn.
Measures.
Coal and shale.
Top Grit of Grassington Moor.
Shale and coal.
Bearing Grit of Grassington Moor.
As throughout the greater part of Upper Wharfedale the Bearing
Grit lies immediately on or close to the Main Limestone of Phillips’
224 J. R. Dakyns—Millstone Grit of Grassington.
Yoredale Series, we have here a well-marked and natural division
between the Yoredale Beds and the Millstone Grit.
The Bearing Grit is so called because the lead veins are very rich
in this bed. .
A tolerably persistent coal, ranging up to ten inches in thickness,
occurs in the overlying shales, and a coal up to six inches thick lies.
on or near to the Top Grit.
The sandstone of Priest Tarn probably corresponds to a bed which
further north forms Pinlow Pike, and is in Coverdale, though thin,
very persistent and of a well-marked character, being a hard
siliceous rock.
The next important rock is the bed we call the Redscar Grit. It
is a coarse felspathic grit of a very red tinge, which is apt to form
such conspicuous red scars that it can be recognized miles off. This
rock, like the Grassington group, often consists of two members
parted by a shale band containing a coal-seam, and it thus forms
a double feature. In this part of the country it generally has on
or near its top a thin bed of peculiar limestone that has the appearance
of a tesselated pavement. This tesselated limestone forms a very
good horizon as the top of the rock, which we correlate with the top
of the Kinder Scout Grits.
The next important rock is that which forms Henstone Band.
We correlate it with the lower grit of Follifoot Ridge.
I will now briefly describe the run of the principal beds. Im-
mediately north of the Craven Fault the Lower Millstone Grits strike
west from Bewerley across Grimwith Fell towards Grassington.
Near this village they turn north and run by the mines across
Grassington Moor, Black Edge, and Coniston Moor. ‘They are thrown
down to the north of Yarnbury by the New Rake Vein, then up by
Beaver Vein, and after several small breaks are finally thrown up
on the north by the Bycliffe or Black Vein.
This great vein runs from Bycliffe along Groove Gill, crosses.
Gateup Gill, where the fracture is seen, and thence crossing north of
Wigstones it runs down Stony Groove to Merrifield, and thence
into the Craven Fault near Pateley Brig. This vein is the most
northerly and greatest in throw of the many veins on Grassington
Moor. They seem all to be more or less connected with the Craven
Fault, to which they are roughly parallel or with which they make
small angles.
The Redscar Grit occupies the northern part of Appletreewick
Moor and Hebden Moor. It forms a fine escarpment along the sides
of Gateup Gill. It is thrown up to the north by the Bycliffe Vein
so as to form the escarpment of Rather Standard, at the north end
of which it is thrown up on the west, so that the top of the rock,
which runs up Henless Beck, is now found in Meugher Dike.
This top is well marked by the tesselated limestone which is found
in place in Henless Beck and in Meugher Dike.
The rock forming Sand Haw seems from its position to be part of
the Redscar Grit. It is a peculiar rock, being hard, close-grained,
and siliceous, and is used for making whetstones, for which purpose
Notices of Memoirs—Dr. Andrews—Evolution of Proboscidea. 225
it is, or used to be, transported for long distances. It is somewhat
similar to the Redscar Grit of Wolfry Crags, but is quite unlike the
general character of this bed.
It is noteworthy that I found near the base of the Redsear Grit
in Gateup, bands of calcareous sandstone. Similar bands, as I am
informed by Mr. J. G. Goodchild, generally occur under the rock
which in Wensleydale was identified on purely stratigraphical
grounds with the Redscar Grit.
This grit is the ‘middle grit’ of the late Professor Phillips
mentioned on p. 65 of his “Geology of the Mountain Limestone
District,” and he is quite correct in saying that it corresponds in
position with the top grit of Penhill.
aN Orr (GsstS) | (az AVMEISHIM NOME Sis ASHES,
On THE EXvoLuTION oF THE ProzoscipEa. By C. W. ANDREWS,
D.Sce., F.G.S., F.Z.8., of the Geological Department, British
Museum (Natural History).'
(eae the author’s recent discoveries of primitive Proboscidea
in the Middle and Upper Eocene formations of the Fayum,
Egypt, the oldest known members of this mammalian order were
Dinotherium Cuviert and Tetrabelodon angustidens, from the base
of the Miocene in France. The new Hgyptian fossils not only
reveal for the first time the early history of the order, but also
provide more satisfactory material for the discussion of its evolution
than has hitherto been available.
The most important changes in the Proboscidea occur in the skull,
mandible, and dentition.
Owing to the increase in the size of the tusks and to the presence
of the proboscis, the facial region of the skull becomes shortened,
and at the same time the premaxilla become wider. The presence
of the proboscis also accounts for the position of the external nares.
The demand for a greater surface of attachment for the muscles
supporting a skull rendered heavy by the tusks and trunk, is met
by the great development of the diploé in certain of the cranial
. bones, resulting in the enormous expansion of the forwardly sloping
occipital surface. The maxille become greatly enlarged con-
comitantly with the increase in the size and degree of hypselodonty
of the molars. At the same time the zygomatic arch becomes
weaker and the jugal takes a smaller share in its composition.
The mandible is at first short and stout, with a massive symphysis.
Afterwards it becomes more and more elongated as the stature of
the animals increases; and this elongation is for the most part
effected by the lengthening of the symphysial region, though the
backward rotation of the ascending ramus tends to the same end.
The prolongation of the mandible beyond the premaxille must
have been covered by a proboscis-like structure composed of the
upper lip and nose, probably more or less prehensile at its extremity.
1 Abstract of a paper read before the Royal Society of London, March 26th, 1903 ;
communicated by Professor E. Ray Lankester, F.R.S. .
DECADE IV.— VOL. X.—NO. V. 15
226 Reviews—Dr. Wheelton Hind’s Chart of Fossil Shells.
The lengthening of the mandible seems to have reached its maximum
degree in the Middle Miocene, after which it again became shortened
by the reduction of the symphysis, while the fleshy and now mobile
proboscis was left behind as the sole organ of prehension.
In the upper dentition the chief changes are the loss of incisors
Nos. 1 and 3, and the great increase in size of incisor No. 2, which
eventually forms the great tusk characteristic of the later Proboscidea.
The canines are soon lost. In the earliest forms, some at least of
the cheek-teeth (milk-molars) are replaced by premolars in the
usual manner, and these teeth remain in wear simultaneously with
the true molars; but in later forms no vertical succession takes
place, and as the milk-molars are worn they are shed, being replaced
from behind by the forward movement of the molars. Of these
also the anterior may be shed, until at length in old individuals
of the later types the last molar is alone functional. The gradual
increase in the complexity of the proboscidean molars is one of
their most striking characteristics. All stages can be traced between
the simple, brachyodont, bilophodont (quadritubercular) molars of
Meritherium (Middle Hocene) to the extraordinarily complex type
of tooth found in Hlephas. ‘Thus in Palgomastodon (Upper Eocene)
the molars are trilophodont, and the same is true of the first and
second molars of Tetrabelodon (Miocene), in which, however, the
last molar is complicated by the addition of further transverse
crests. In the Stegodonts of the Siwalik Hills (Pliocene) a further
increase in the number and height of the crests takes place, and
the whole crown of the tooth is more or less covered with a thick
coat of cement. Still later, the transverse crests become highly
compressed laminz united by cement, and these are as many as
twenty-seven in number in the Pleistocene Hlephas primigenius and
the recent £. indicus.
The evolution of the lower molars corresponds with that of the
upper molars. Of the lower incisors the middle and outer pairs
(Nos. 1 and 8) are soon lost, but the second pair remains functional
for a long geological period. When the symphysis becomes
shortened, these incisors are sometimes retained as vestiges (e.g. in
Mastodon americanus), but in the genus Elephas they have com-
pletely disappeared.
Tee) SERV 5 le BE VV Se
].—Cuarr oF Fossin SHELLS FOUND IN CONNECTION WITH THE
Seams or Coan AnD Ironstone or Norra STAFFORDSHIRE.
By Wauee.tton Hinp, M.D., F.R.C.S8., F.G.S., and Jonn Stops,
F.G.S. (Published by the North Staffordshire Institute of
Mining and Mechanical Engineers, 1903. Price 5s.)
T is an acknowledged fact that, compared with many other com-
mercially less important geological formations, very little is
known about the distribution of the fossils among the Coal-
measures. In this respect the North Staffordshire Coalfield has
been more carefully searched than others, though outside the
Reviews— Geological Report of Cape of Good Hope. 227
district this typical Midland coalfield is not so well known as
the excellence of the sequence and preservation of its organic
contents warrant. The chart by Messrs. Hind and Stobbs should
draw attention to this region, for besides being of use_to the
mining student it will be found to be of more than local value,
and should be studied by all interested in the Coal-measures.
The chart gives the order of sequence, distance apart, and
synonyms of the seams of Coal and Ironstone of the Pottery and
Cheadle Coalfields, in two sections drawn on a scale of 200 feet
to the inch. The fossil shells distinctive of or especially abundant
on certain horizons are drawn opposite to the particular bed in
which they occur. No attempt has been made to subdivide the
Coal-measures beyond the use of merely local terms for the higher
portion of the sequence. Marine organisms are represented as
occurring on three horizons—at the base, near the middle, and
towards the summit of the coal-bearing strata. . A noticeable
omission, evidently due to extreme caution, is the band, rich in
marine organisms, found many years ago by Mr. John Ward above
the Gin Mine at Longton. Thin limestones with Spirorbis, so long
held to be distinctive of the higher Coal-measures, are represented
at two horizons low in the sequence. The fossils are clearly drawn,
while their selection by Dr. Wheelton Hind guarantees that the
typical forms have heen chosen.
The authors have evidently taken great care in planning and
‘drawing up the chart: it is to be hoped the Mining Institutes in
other coalfields will follow the example of that of North Stafford-
shire by publishing similar charts, and thus show that they recognize
the close union of the two sciences of Mining and Geology.
Watcor GIBson.
II. —Care or Goop Horr. Annvuat Report oF THE GEOLOGICAL
Commission, 1900. 4to; pp. 93. (Richards & Sons, Cape
Town, 1901.)
J. The results of the survey of parts of the Uitenhage and Port
Hlizabeth districts (pp. 1 to 18). The Sunday’s River Marine
Beds, the Wood-bed series, and the Enon Conglomerate series
constitute the great Uitenhage series; and these were studied in
the Zwartkop Valley, the Bezuidenhout Valley, and on the White
River and the Sunday’s River. The fossil fauna and flora are
referable to both the Jurassic and the Cretaceous series ; and are here
provisionally regarded as Upper Jurassic. The occurrence of much
more recent deposits near the coast are alluded to. The observations
made by earlier geologists on the district are carefully noted.
II. (Pages 19-54.) A survey of parts of Clanwilliam, Van Rhyn’s
Dorp, and Calvinia divisions led to the definite recognition of
a separate series of sedimentary rocks (shales, sandstones, vein-
quartz, quartzite, limestone, and conglomerate) underlying the
Table Mountain Sandstone, and resting on the Malmesbury series.
The conglomerates are decidedly glaciated, and much resemble
those of the Congo in Oudtshoorn in some respects. The sandstones,
228° Reviews—Geological Report of Cape of Good Hope.
false-bedded and ripple-marked, show worm-casts and definite
animal trails. This Ibiquas series (named after a local tribe of
natives) extends from the north-eastern part of Van Rhyn’s Dorp
district into Calvinia; it appears to be much thicker than the
Bokkeveld series, which in places is seen to be unconformable
above it.
In this survey we have also an account of the local range of
the Table Mountain Sandstone, the Bokkeveld Beds, the Dwyka
series, and its continuation to Prieska and Hope Town. ‘The
peculiar White Band, lying on the Dwyka Conglomerate, owes its
appearance to the slow combustion of a carbonaceous shale under
atmospheric agencies. The thick shales and sandstones of the
Ecca series, above the White Band, contain some ferns and calamites
in the south. The local dykes and sheets of Dolerite are described
in detail. They all belong to one series of intrusions; and, like
the Karoo dolerite type, consist of a moderately coarse plagioclase-
augite-olivine rock.
III. The survey from Beaufort West to Calvinia (pp. 55 to 64)
showed mostly horizontal beds of the Karoo series of shales and
sandstones, pierced vertically and horizontally with dykes and
sheets of the usual dolerite. The shape and constitution of the
hills very much depend on the presence of this intrusive rock and
the peculiar modes of its weathering. A remarkable cylindrical
hole, near Ratel Fontein, in sandstone and shale, is filled with rocks
and minerals such as are found elsewhere associated with diamonds,
but they are absent here.
IV. (Pages 65 to 79.) The geology of the Cedarbergen and
adjoining country between the Gydr Pass on the south and the
Pakhuis Pass on the north comprises the Table Mountain Sand-
stone, the Bokkeveld, and the Witteberg series. In the Table
Mountain Sandstone (Lower Devonian) of the Pakhuis Pass there
is undoubted evidence of local glacial action contemporaneous with
the deposition of the sandstone and shale or mudstone, with glaciated
pebbles in early Devonian times.
In a separate paper on this Glacial Conglomerate in the Table
Mountain Sandstone read before the South African Philosophical
Society in February, 1901, Mr. A. W. Rogers gave further par-
ticulars as to the character and condition of this deposit, illustrated
by a plan and section (Trans. 8.A. Phil. Soc., vol. xi, pt. 4,
pp. 286-242). He states that ‘‘The shale band was first recognised
by Mr. Schwarz in the Hex River and Warm Bokkeveld Mountains..
In the Ist Ann. Rep. Geol. Comm. C.G.H. for 1896, p. 27, he
describes two shale bands, one near the Table Mountain Sandstone
and the other near the bottom: the upper of these two is the one
referred to above. The course of this band between the Schurfte-
bergen and Pakhuis is described in the 5th Ann. Rep. for 1900.”
The results of 1900 were obtained under very disadvantageous
circumstances owing to the War, but they have been welcome
additions to geological knowledge: (1) especially as to the relationship
of the Ecca series and the associated so-called Dwyka Conglomerate
Reviews—Guide to Antiquities of the Stone Age. 229
to the formations above and below; (2) the existence of a separate
formation (Ibiquas) between the Table Mountain Sandstone and the
Malmesbury Schists; (3) a definite glacial conglomerate in the Table
Mountain Sandstone; (4) the careful and systematic examination
of the probably Upper Jurassic in the Hast Province round about
Uitenhage confirms and gives welcome additions to what was
known before.
The work has been done by A. W. Rogers and EH. H. L. Schwarz.
Dr. Corstorphine, while Director of the Survey, made the useful report
before us, and on his resignation, we understand, was succeeded by
Mr. Rogers. We have no doubt of the further good progress of
this Survey. T. BR. J.
I1].—British Museum. A GuIpDE To THE ANTIQUITIES OF THE
Stone AGE IN THE DEPARTMENT oF British anp Mrpimvat
Antiquitizs. Pages xii and 124, with ten plates and 142
illustrations. (British Museum, Bloomsbury: printed by order
of the Trustees, 1902. Price 1s.)
R. CHARLES H. READ, F.S.A., the Keeper of British and
Medizeval Antiquities, who is the author of this admirable
Guide, has conferred a great service on the ordinary Museum visitor,
who “‘ wants to know,” and is at a loss to find out for himself the
hidden meaning of things. He is like the Ethiopian eunuch of old
and wants some man to guide him. Mr. Read kindly comes forward
and at once the difficulties of understanding the collection disappear.
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Fic. 1.—Triangular implement, Herne Bay. (Fig. 6, p. 18 inGuide.) 4 nat. size.
The period in human history represented by the ‘Stone Age’
is just that most difficult of all chapters to write, because the
evidence is so largely inductive, and depends for the earlier or
230 Reviews—Guide to Antiquities of the Stone Age.
Paleolithic period to so great an extent upon geological data, that
one would naturally expect to have to pay a visit to the Cromwell
Road Branch of the British Museum at South Kensington in order
to understand the stratigraphical aspect of our Harth in relation
to early Man as one of its inhabitants. Mr. Read, however, in
the first 14 pages of his Guide, gives us an excellent resumé of
the Paleolithic period, and takes us back first to the discovery by
Mr. Conyers (at the end of the seventeenth century) of a flint
implement, in gravel, near Gray’s Inn Lane, London, together with an
Fic. 2.—Shoe-shaped implement, Northfiect. (Fig. 8, p. 19 in Guide.) § nat. size.
elephant’s tooth; and then on to Mr. John Frere’s researches a century
later (1797), and the finding of flint implements in river gravel at
Hoxne, Suffolk, which the discoverer referred “to a very remote
period indeed, and to a people who had not the use of metals.”
No other records occur of finds in valley gravels until M. Boucher
de Perthes’ exploration of the deposits of the Somme Valley at
Abbeville (1850), where large quantities of implements evidently
fashioned by the hand of man were found.
It is due, however, to the Rev. J. McEnery (a Roman Catholic
priest living at Torquay, 8. Devon) to mention that, so far back as
1825,’ he had discovered (noé in river gravel, but) in Kent’s Cavern,
1 Published by E. Vivian, Esq., 1859.
Reviews—Guide to Antiquities of the Stone Age. 231
Torquay, evidences of man in the form of flint flakes and stone
implements, associated with the remains of Hyzna, Reindeer, Cave-
bear, and the sabre-toothed Tiger or Lion (the Macherodus), together
with the Mammoth and Rhinoceros.
The truth of McEnery’s discoveries remained unverified until forty
years afterwards, when Pengelly’s exploration of Kent’s Cavern placed
the accuracy of McHnery’s original observations beyond a doubt.
The stone implements sent up to Professor Buckland eighty years
ago by McHnery seem to have disappeared, but the remains of
Macherodus and Hyzna were preserved, and testify to the value
of his work as an original observer and discoverer of early Man.
ts ns
Fie. 3.—Chert implement with curved edges, Broom, Dorset.
(Fig. 15, p. 25 of Guide.) 3 nat. size.
A diagram is given by Mr. Read (on p. 2) to show the evidence as
to the geological antiquity of the river-valley gravels containing the
flint implements in the valleys of the Somme, the Thames, and else-
where. Contrary to other geological evidence, based upon superposition
(where one would at once naturally conclude that the highest beds
were the newest, and the lowest the oldest), in these river-valley
deposits it is the oldest beds of gravel which occupy the highest
of the old river-valley terraces, and the newest gravels which lie
in the bottom of the present river valley. The explanation is so
obvious that (like the story of Columbus and the egg) everyone sees
it must be so, when told that the river in the course of centuries has
gradually deepened its valley, and that whereas it formerly flowed
perhaps hundreds of feet above its present level, it has, by its slow
erosive action (aided by rain, frost, and snow), cut its channel lower
and lower, until it has reached the depth at which we find it flowing
to-day. But the river, in wandering in its serpentine course along
its valley, leaves behind upon its flanks portions of its earlier and
232 Reviews—Guide to Antiquities of the Stone Age.
more elevated level in the shape of terraces covered with beds of
old river-valley gravel (containing flint implements), of which the
highest is really the oldest. ven outside the limits of its valley
we find that still older watercourses have flowed along, and in places
spread sheets of gravel over the plateau far above the reach of any
modern flood-waters. In this very ancient gravel implements of a far
ruder type than those commonly known as ‘ Paleolithic’ are met
with. These have been accepted as weapons made by some early
and most uncivilized race of mankind, and are termed ‘ Eoliths,’ good
examples of which, collected by the Rev. R. Ashington Bullen, may
29
Fic. 4.—Chopping tool, province of Poitou. (Fig. 29, p.32 in Guide.) 4} nat. size.
be seen figured in Plates VI and VII of this Magazine for March
last (pp. 102-110). “It is not” says Mr. Read (p. 10), “the
province of the present Guide to enter into the arguments which
have been brought forward against or in favor of the artificial
character of Holiths, but it may be said that whether their claims
can be substantiated or not, the existence of implements of a ruder
kind than those of the drift is in itself not improbable. For no
invention reaches perfection suddenly, and each stage of advance is
attained by an infinitely slow progress from the simple to the more
Reviews—Guide to Antiquities of the Stone Age. 233
complex. The majority of the drift implements are clearly something -
more than the first efforts of an unpractised hand; they show, on
the contrary, signs of a comparatively long development, and it may
be fairly argued that their ruder prototypes must exist somewhere.
Fie. 5.—Axe-head with hollowed Fie. 6.—Flint chisel, Denmark.
edge, Denmark. (Fig. 96, p. 89 (Fig. 97, p. 89 of Guide.)
of Guide.) #2 nat. size. % nat. size.
It was to be expected that they should have escaped notice for a longer
time than the typical Paleoliths, if only because they must necessarily
Fie. 7.—Chipped knife of chert, Sheikh Hamadeh, Egypt.
(Fig. 101, p. 95 of Guide.) 4 nat. size.
“We may draw similar conclusions from a consideration of the
stone implements of the most primitive savage tribes. The knives
of the now extinct Tasmanian aborigines were of the rudest
description, generally chipped only on one side, and quite devoid
of symmetry. The Andamanese had implements of a yet more
elementary kind, and the Semang, a similar negrito tribe of the
Malay Peninsula, are said only to have stone implements in the
234 Reviews— Guide to Antiguitics of the Stone Age.
sense that they pick up and use such convenient fragments as
they may chance to find, usually employing shell, bamboo, or
wood to provide for their simple needs.
There are therefore still
in existence peoples to whom, from climatic and other reasons,
stone implements are of only secondary importance; and though
F
Y
Fic. §.—Flint knife, Denmark.
(Fig. 115, p. 103 of Guide.) 4 nat. size.
Fic. 10.—F lint javelin-
head, long barrow,
Wilts. (Fig. 138,
p. 114 of Guide.)
Hitcham, Bucks. (Fig. 121,
p. 106 of Guide.) $ nat. size.
their civilization is low, it must be higher than that of the earliest
representatives of the human race.
Yet supposing the negrito
tribes had died out before their countries had been discovered by
Huropeans, the extremely rough character of their stone tools would
probably have led anthropologists to reject them as of human
Reports and Proceedings—Geological Society of London. 235
handiwork, or to assume that they were made by anthropoid apes.
The search for evidence of man’s existence before the drift-gravels.
of the present river-systems of Western Europe were deposited is,
at any rate, justified by analogy, though how long before, zoology
and anthropology must decide. What is quite certain is that the
extreme rudeness of a chipped flint is not in itself a ground for
its rejection as the work of man.” (p. 11.)
The time and space at our disposal will not permit us to do
adequate justice to Mr. Read’s excellent Guide, which must certainly
take a foremost place among such works, of which the Museums of
Bloomsbury and Cromwell Road now possess a most admirable series.
We have borrowed only 10 out of the 199 illustrations which adorn
this work, 142 being given in the text, while 57 half-tone figures
make up ten beautifully printed process plates. The illustrations
are for the most part original, and give examples of weapons of
every form, country, and stage of development in the Age of Stone.
Polishing appears to mark the later and more advanced period of
culture, but when we examine the exquisite workmanship of the
chipped and unpolished chert knives from Egypt, one is led to marvel
at the very fine art in the manufacture of weapons in flint to which
the ancient Egyptians must have attained before they were able to
fabricate such lovely knife-blades in silex. In addition to several
geological sections and views of ancient and modern pile-dwellings,
there are about twenty drawings of carved bones, and pictures of
animals on bone, given to complete this charming little book on the
‘Stone Age.’
We have but to add that the price is only one shilling and
everyone, we feel sure, will buy a copy.
ee Orr SAIN) | I © Czas EGS.
GroLoGicaL Soorrety or Lonpon.
I.—March 11th, 1903.—Prof. C. Lapworth, LL.D., F.R.S., President,
in the Chair. The following communications were read :—
1. “ Petrological Notes on Rocks from Southern Abyssinia
collected by Dr. Reginald Kooettlitz.” By Catherine A. Raisin, D.Sc.
(Communicated by Professor T. G. Bonney, D.Sc., F.R.S., F.G.S.)
The specimens described in this paper were collected by
Dr. Keettlitz on an expedition (in 1898-99), starting from Berbera,
westward through Somaliland and Southern Abyssinia, and turning
northward to the Blue Nile. The paper gives petrological notes on
the different classes of rocks represented. The crystalline rocks
include granite, gneiss, and hornblende-schist or foliated diorite,
together with more basic types. They occur where the plateau
rises from the coastal plain, farther west underlying volcanic rocks
and sedimentary strata, in the south-west of Abyssinia, and towards
the Sudan. Some of the gneisses exhibit pressure effects, as if these
older masses had been thrust up. The more basic types include
diabase, hornblende-gabbro, and one lustre-mottled hornblende-
pyroxenite, resembling a picrite.
236 Reports and Proceedings—Geological Society of London.
The sandstones (which are chiefly from Somaliland and the
south-east of Abyssinia) are sometimes compacted into quartzites,
and are often ferruginous. Some of the limestones are concretionary,
others are dolomitic, and several from different localities are fossil-
iferous, containing foraminifera, calcareous alge, and, at Jigjiga
Pass (which leads into Abyssinia), Turritelle in great numbers.
The numerous specimens of volcanic rocks include one which is
practically a limburgite, many basalts (a few with olivine, and some
glassy), various less basic volcanic rocks, and several pumiceous
tuffs. But the most interesting are the phonolites and allied rocks,
containing nepheline, riebeckite, or other alkaline minerals. They
occur at several places, one being a volcanic hill with a summit-
crater. The authoress distinguishes several types among these
soda-bearing rocks, and compares two of them with rocks of Central
Abyssinia and of British Hast Africa respectively. Thus the
specimens here described may form a connecting link between the
volcanic rocks of other Hast African localities.
2. “The Overthrust Torridonian Rocks of the Isle of Rum and
the Associated Gneisses.” By Alfred Harker, Esq., M.A., F.R.S.,
F.G.S. (Communicated by permission of the Director of H.M.
Geological Survey.)
The Torridonian strata of Rum occupy all the northern part of the
island, together with a strip extending along the eastern coast, the
high ground in the south being made by plutonic rocks of Tertiary
age. The northern tract consists in general of sandstones having a
moderate dip to the north-west or west-north-west, and below these
there emerges on the east side a lower group composed of dark
shales. There are, however, two districts in which the strata are
highly disturbed and overthrust. One is a small area to the north-
west, on Monadh Dubh, where a cake of thoroughly brecciated and
mylonitized rocks rests on the relatively unmoved sandstones.
Besides sandstone, this crushed mass contains abundant débris of
Cambrian limestone, chiefly towards the base, and resting immediately
upon the surface of overthrust. The limestone does not occur in
place on the island.
The other and more extensive area of overthrust rocks forms
a belt along the north-eastern and eastern border of the mountain
tract. The effect of the displacement has been to bring the shales
of the lower group to rest on the sandstones of the upper. Above
the main surface of movement the shales are violently contorted,
and the sandstones, where these occur, brecciated. There is also
considerable thermal metamorphism, due to the Tertiary intrusions.
At numerous places along the disturbed belt are patches and lenticles
of gneiss. These are intrusive in the Torridonian rocks, and the
evidence points to their being of Tertiary age. They have arisen
in great part from a granitic magma modified in varying degree by
dissolving basic, and often ultra-basic, rock-débris. The hetero-
geneous composition thus imparted has, with flowing movement,
resulted in a well-marked gneissic banding. Ina minor degree basic
rocks, probably gabbros originally, have contributed more directly
Reports and Proceedings—Geological Society of London. 237
to the composition of the complex, namely, as bands or lenticles of
rocks, now hornblendic, representing distinct intrusions enveloped
and modified by the later and more voluminous invasion of acid magma.
The chief conclusions which the author wishes to establish are :—
(i) That the highly disturbed region of the North-West Highlands,
already known to extend into the south-eastern part of Skye, is
further prolonged into the Isle of Rum.
(ii) That at numerous places along the disturbed belt which
borders the principal mountain group of the island, the Tertiary
plutonic intrusions assume the character of well-banded gneisses,
comprising alterations of different lithological types.
(iii) That these complex gneisses were formed mainly by fluxion
in a heterogeneous mass, the heterogeneity being due to the
inclusion and incorporation in a granitic magma of relics of nltra-
basic and basic rocks.
II. — March 25th, 1903. — Professor Charles Lapworth, LL.D.,
F.R.S., President, in the Chair. The following communications
were read :—
1. “On a New Species of Solenopsis from the Pendleside Series
of Hodder Place, Stonyhurst (Lancashire). By Wheelton Hind,
M.D., F.R.C.S., F.G.S.
This specimen of a perfect left valve was found by the Rev.
Charles Hildreth in shales belonging to the Pendleside Series,
which have yielded the following fossils: Phillipsia Van-der-
Grachtii, Ph. Polleni, Prolecanites compressus, Glyptoceras spirale,
Gl. reticulatum, Gl. platylobium, Orthoceras annulosolineatum, Posido-
nomya Becheri, Solenopsis major, and a few Brachiopods.
2. “Note on some Dictyonema-like Organisms from the Pendleside
Series of Pendle Hill and Poolvash.” By Wheelton Hind, M.D.,
F.R.C.S., F.G.S.
Mr. D. Tate discovered a specimen, in the shales and limestones
in the Angram Brook, which had some resemblance to a Dictyonema ;
and he afterwards found another similar specimen, on or about the
same horizon, at Poolvash. These are referred to distinct species,
and doubtfully assigned to the genus Dictyonema. A piece of shale
from the Bishopton Beds in Glamorganshire has somewhat similar
but less distinctly reticulate markings.
3. “The Geology of Tintagel and Davidstow District (Northern
Cornwall).” By John Parkinson, Hsq., F.G.S.
The country described and mapped consists of some 22 square
miles in Northern Cornwall, extending from the coast eastward
towards Camelford Station and St. Clether. In the eastern part
it extends to the neighbourhood of the Brown Willy mass of
granite, while on the north it approaches the boundary between
the Lower Culm and the Upper Devonian. The rocks described
are of the latter age, and contain Spirifera disjuncta.
Except in the southern coast region (Tintagel and Trebarwith
Strand) the strike is fairly uniform in an east-south-easterly and
west-north-westerly direction, the beds having a northerly dip ;
238 Reports and Proceedings—Geological Society of London.
but north and south of Tintagel Head the higher members appear,
greatly faulted, being brought in out of their true position partly
by a change of strike, partly by dip-faults. The most distinctive
rocks, utilized as a datum for mapping, are a group of ashes and
lavas. The latter are often amygdaloidal, and possess original
characters which are still recognizable; but the whole group is
frequently much altered or entirely reconstructed, with the formation
of epidote (sometimes enclosing allanite), sphene, biotite, chlorite,
etc. The rocks are associated in many instances with calcite, at
least partly due to contemporaneous deposition, but frequently
forming a corporate part of the renovated rock, and the mineral
is found with quartz and translucent felspar.
Bluish-black slates and finally laminated quartzose beds overlie
and underlie this volcanic series.
The remaining rocks are phyllites, closely resembling those from
the Ardennes. The author divides them into four groups. The
highest of these (Tredorn Beds) overlies the uppermost division
of the Blue-Black slates, and in the western part of the district
contains a mineral forming small white spots, not yet determined.
The beds underlying the Lower Blue-Black slates (Halwell Cottage
Beds) are banded phyllites, with quartzose lamine, typically con-
taining abundant crystals of clinochlore with a habit resembling
that of ottrelite. The underlying phyllites (Penpethy Beds and
Slaughterbridge Beds) contain no distinctive mineral. Taken as
a whole, the phyllites consist of a sericitic and chloritic groundmass
containing unorientated crystals of white mica, micaceous ilmenite,
hematite, and minor quantities of tourmaline and rutile. North-
east of Camelford (Grigg’s Down) they furnish clear evidence of
contact-metamorphism.
III. — April 8th, 1908. —J. J. H. Teall, Esq., M.A., F-.RB.S.,
Vice-President, in the Chair.
Professor W. W. Watts drew attention to the exhibit on the table
of the new series of Platinotype Photographs issued by the Geological
Photographs Committee of the British Association.
The following communications were read :—
1. “On the Probable Source of some of the Pebbles of the Triassic
Pebble-Beds of South: Devon and of the Midland Counties.” By
Octavius Albert Shrubsole, Esq., F.G.S.
After an account of previous researches on this subject, the author
proceeds to describe the Budleigh Salterton Pebble-Beds. Judging
from lithological evidence, the bulk of the pebbles must have come
from a definite region of a comparatively simple geological character ;
and this is confirmed by the paleontological evidence. The sup-
position is natural that Devonian rocks were once represented
either in the Calvados district or in some region in the same
drainage area as that which has supplied the Ordovician element.
The Grés de May of Normandy and its associated rocks are next
described, a massif which, according to Professor Bonney, must
have exceeded the Alps in breadth. When regard is had to the
extent and original thickness of the Grés de May, it appears capable
Correspondence—A. K. Coomaraswamy. 239
-of furnishing abundant material, not only for the Ordovician pebbles
of the Budleigh Salterton Pebble-Bed, but also for a great deal
more. A list of species common to the Grés de May, of May itself,
and the Budleigh Salterton deposit is given; and it is pointed out
that in the Department of the Manche the former deposit varies in
paleontological facies. In addition to the identity of the quartzites
and felspathic grit in the two areas, it is noted that the so-called
lydianstone (tourmaline-grit) of Budleigh and the Midlands may
be paralleled with one referred to by MM. de Tromelin and
Lebesconte in the Department of Maine-et-Loire. The author is
struck with the resemblance of the Midland Bunter to that of
Devon, and he gives the percentage of rock-types in the larger
pebbles at Repton and in the smaller material of Drift derived from
the Bunter at two localities in the Lickey Hills. Strong family
likenesses subsist between certain specimens in the northern and
southern Bunter and some of the undisturbed rocks of Normandy.
A list of fossils from the Midland Bunter contains three southern
forms; and a further table is given comparing fossils from Drift-
pebbles from Budleigh Salterton and from Normandy. Fourteen
out of twenty of the Drift and Bunter fossils are found at Budleigh
Salterton and in Normandy. The hypothesis which presents the
least difficulty appears to be that which regards the two pebbly
deposits, north and south, as having had approximately a common
origin. It does not necessarily follow that both deposits are due
to the same river.
2. ‘Note on the occurrence of Keisley Limestone Pebbles in the
Red Sandstone Rocks of Peel (Isle of Man).” By EH. Leonard Gill,
Hsq., B.Sc. (Communicated by Prof. W. Boyd Dawkins, D.Sc.,
F.R.S., F.S.A., F.G.8.)
Pebbles of a coarsely crystalline, greyish-white, mottled lime-
stone, collected by Prof. W. Boyd Dawkins from the conglomerates
at Whitestrand, contain the following fossils: Illenus Bowmannz,
var. brevicapitatus, Primitia Maccoyi, Orthis calligramma, O. testudi-
naria, O. biforata, Rafinesquina deltoidea, Plectambonites quinque-
costata, Atrypa expansa, Hyatella Portlockiana, Dayia pentagonalis,
Platyceras verisimile, Stenopora fibrosa, and crinoid stems. This
assemblage of fossils corresponds strikingly with that of the Keisley
Limestone; and it is therefore concluded that the pebbles have been
derived from that rock. It seems hardly likely that they have come
from so distant a locality as the Lake District; more probably there
has been a local source, which would form a link between the lime-
stone of Keisley and that of the Chair of Kildare.
CORRESPONDENCE.
THE GELOLOGISCHES CENTRALBLATT.
Sir,—Dr. Keilhack’s invitation to authors to supply their own
abstracts comes none too soon; it is to be hoped that this plan will
prevent the mistakes which are apt to occur under the present régime.
In the current number (March) two papers by myself on the
Crystalline Limestones of Ceylon are reviewed. The abstract of
240 Correspondence—Dr. Callaway.
the longer paper (p. 228) seems to show that the abstractor has no
knowledge of crystalline rocks; otherwise he would not suppose that
anyone could divide a series of limestones into gneisses, limestones,
and granitites! Moreover, instead of reading the paper itself he has
made use of the abstract printed by the Geological Society before
the publication of the paper, and so actually credits the paper with
containing a discussion of the origin of the limestones which in
reality appeared elsewhere in a slightly modified form.
In the case of both references the author’s name is incorrectly
quoted. I should like also to take this opportunity of calling
attention to the numerous misprints which occur in the pages of the
Centralblatt fiir Mineralogie, etc.; see e.g. pp. 28, 29, 32, 60, 62 of
the current year’s issue. A. K. Coomaraswamy.
PERADENIYA, Cryton, March 23rd, 1903.
PROFESSOR W. M. DAVIS AND RIVER CURVES.
Srr,—Professor Davis, in your issue for April, criticizes my little
paper of October last, and offers an alternative theory. I laid down
the rule that, ‘“‘in the vast majority of cases, the affluents of rivers
enter on the convex side of the curves.” Mr. Davis admits the truth
of this rule (p. 148), and therefore his criticisms and his theory must
be consistent with it.
He cites cases where affluents form deltas at their mouths, and the
main stream bends away from the tributary. Such exceptional
examples were discussed by me, but it seems scarcely logical to
quote them as hostile to a theory which only professes to explain -
cases where the rivers bend towards their affluents.
Professor Davis attributes to me a belief in “an initially straight
main river.” I did not assert, or even suggest, that such a thing
ever existed. I merely assumed straight courses for short distances.
We often get these even in oldish rivers, and they must have been
incomparably more frequent in new ones. I suppose that a river
has its tributaries even when itis young. If the shape of the ground
has given rise to a bend towards an affluent at this stage, my theory
is unnecessary. It is only required to account for the production of
a bend when the course happens to be straight, which must often
have been the case.
But Professor Davis offers a theory of his own. He explains my
rule as due to the motion down the valley of the ‘“‘ meander system,”
so that, sooner or later, convex curves capture affluents entering on
the concave. But this is only possible, as shown by his explanation
and diagram (fig. 3, p. 147), where the meander system is in an
advanced stage. The coming in of most tributaries on the convex
curve has been determined much earlier. Professor Davis cannot
deny this without denying the rule, which is based upon the study
of rivers in all stages of development. His diagram (fig. 3) with
its crowd of affluents entering on the concaves is not true to nature,
or to the rule which he concedes to be true to nature. I fail,
therefore, to see how the Professor’s explanation can be “ normal,
effective, and fully verified.” C. CaLLaway.
CHELTENHAM, April, 1903.
THE
GHOLOGICAL MAGAZINE
NEW SERIES!) "DECADE TIVe VOL. X:
No. VI.—JUNE, 1903.
Gs bEribiny Avda) ys b Ie Quin waHsS}-
I.—Cave Huntine in Cyprus.
By Henry Woopwarp, LL.D., F.R.S., F.G.S.
ROM the days when Nimrod began to be “a mighty hunter before
the Lord,” down to those in which our friend Fred. C. Selous
shot ‘big game’ in Africa, the hunter has always occupied a
specially exalted position and enjoyed a much envied notoriety in
all countries. But alas for the wild animals! they are now rapidly
becoming exterminated by man, and their place on the prairie, the
pampa, the veldt, and in the forest will soon know them no more.
Karly in the last century, that enthusiastic geologist Dean
Buckland invented a new sport, devoid of slaughter or destruction
of life, yet full of the keenest interest for the zoologist and the
geologist, namely, the hunting for wild animals in cave deposits.
The later poet of Kent’s Cavern wrote :—
*¢ Full many a tooth with cutting edges keen
The virgin limestone caves of England bear ;
Full many a bone of elephant, I ween,
Awaits the hunter who shall seek it there ! ’’
After labouring in Kirkdale, the Mendips, the Gower Caves, and
those of Germany, France, and Gibraltar, Buckland published his
“‘Reliquiz Diluviane” in 1823. Out of more than thirteen caves he
records the discovery of remains of Hyzna, Tiger (Macherodus?),
Bear, Wolf, Elephant, Rhinoceros, Hippopotamus, Wild Boar, Horse,
Deer, Bos, sp., Beaver, and other animals of less interest.
Even at that early date he excited at least one enthusiastic
contemporary, the Rev. J. McHnery, who explored ‘ Kent’s Hole,’
Torquay, and proved the contemporaneity of early man with the
Sabre-toothed Tiger (Macherodus) and other extinct animals in this
ossiferous deposit. But public opinion had not as yet been aroused
to take an interest in the question of ‘the antiquity of Man,’ and
more than thirty years elapsed before further investigations were made,
supported by Lyell, Busk, Schmerling, Falconer, Evans, Lubbock,
Pengelly, Lartet, and Christy, and later on by Boyd Dawkins,
Tiddeman, Hicks, Hughes, and others, down to the many workers
of the present day.
DECADE IV.—VOL. X.—NO. VI. 16
242 Dr. H. Woodward—On Cave Hunting.
After all that has been published upon the subject, one would
have expected that such investigations would have lost their
interest with geologists and naturalists, and also with the public
at large, but this is far from being the case.
So lately as January last, Professor Boyd Dawkins communicated
to the Geological Society of London an account of the discovery in
1901-2 of an ossiferous cavern of Pliocene age at Doves Holes,
Buxton, Derbyshire, which, besides containing Macherodus, Hyena,
Elephas, Rhinoceros, Equus, and Cervus, yielded numerous examples
of Mastodon arvernensis, an animal well known from the Crag, but
no cave in Kurope has hitherto yielded such a Pliocene fauna !
In September, 1898, the fresh skin of a species of Mylodon, a ground-
sloth (named Neomylodon Lista), was discovered in a cavern near
Consuelo Cove, Last Hope Inlet, Patagonia. Other numerous dis-
coveries from the same cave followed, from which it appeared that
many examples of this great sloth had been imprisoned and fed by
man, and ultimately killed and eaten there by an early race of Indians,
who also ate the horse, the huanaco (Auchenia), the bear, puma, and
other animals, and left their remains, and also their own bones and
weapons, to testify to their presence in the cave contemporary with
the Mylodon.
The long series of researches in caves and ossiferous deposits on
the islands and seaboard of the Mediterranean begun more than
fifty years ago, and continued down to the present day, by numerous
English and foreign geologists,’ has resulted in the accumulation of
most important evidence relative to the Eocene, Miocene, Pliocene,
and Pleistocene faunas of this region, particularly those of Gibraltar,
Concud in Spain, Mt. Léberon in France, Olivola and the Val
d’Arno in Italy, the caves of Malta and Sicily, the deposits of
Pikermi and Eubcea in Greece, Samos (Asia Minor), Maragha
(Persia), the Fayum (Egypt). The important discoveries of
vertebrate faunas in the Egyptian Tertiaries have already been
noticed in the pages of this Magazine.?
Having made previous acquaintance with cave-hunting, by the
exploration of a bone-cave on the River Wye and the description
of its mammalian contents (see Grou. Maa., 1901, Dec. IV, Vol. VIII,
pp. 101-106, with 8 text-figures), Miss Dorothy M. A. Bate set forth
in the Spring of 1901 to make an exploration of the caves, said to
be numerous, in the long limestone range of hills forming the
northern border of the Island of Cyprus; she also found similar
ossiferous deposits at Cape Pyla on the south-east coast.
Early in 1902 Miss Bate sent home to Dr. C. I. Forsyth Major
some much worn teeth about the size of a pig’s molars, which
1 We recall the names of Professor Gaudry, Admiral Spratt, Dr. Falconer,
Professor Busk, Dr. Leith Adams, Dr. C. I. Forsyth Major, Dr. Pohlig, Mr. J. H.
Cooke, Dr. A. S. Woodward, and Dr. C. W. Andrews.
2 Grout. Maga., 1899, p. 481, Fossil Mammalia from Egypt; 1900, p. 1,
Podocnemis Algyptiaca; p. 401, Fossil Mammalia from Egypt; 1901, pp. 400 and
436, Vertebrates of Egypt; 1902, p. 291, Extinct Vertebrates of Kgypt; p. 433,
Pliocene Vertebrate Fauna of Wadi-Natrun ; 1903, p. 225, Evolution of Proboscidea.
Dr. H. Woodward—On Cave Hunting. 243
showed no indication of the trefoil pattern so characteristic of the
molars of Hippopotamus. A second small parcel contained a few
less worn teeth, together with a germ-tooth, from which it became at
once evident that we had to do with a mammal of the Hippopotamus
tribe, about half the size of a middle-sized H. amphibius, with molars
exhibiting a modification of the common Hippopotamus pattern,
approximating them to a less specialized type of Artiodactyle teeth.
Dr. Forsyth Major’s account of this discovery, from which we quote,
was published in the Proceedings of the Zoological Society of
London (June 3, 1902; pp. 107-112, plates ix and x) after the
arrival of very numerous remains from Cyprus, obtained by Miss
Dorothy Bate, and carefully developed in the British Museum
(Natural History), Cromwell Road. In his description, the author
compares the small Hippopotamus from Cyprus with the numerous
remains of allied species preserved in the Museum from the other
Mediterranean islands and from elsewhere. Dr. Forsyth Major had
himself obtained and described a pigmy form from Madagascar
(see Groz. Mac., 1902, Dec. IV, Vol. IX, pp. 195-199, Plate XII) ;
another is found living in Liberia, west coast of Africa, at the
present day, though probably verging on extinction. The large
H. amphibius has still a wide distribution on the great lakes and
rivers of Africa, and was once abundant also in Hurope and in
this country ; whilst ZZ. sivalensis is met with fossil in the Siwalik
Hills of India. The Maltese caves and Sicily have yielded abundant
remains of the small Hippopotamus Pentlandi, and of a much smaller
and very rare species from Malta formerly called H. minutus, but
now known as /#. melitensis; this is about one-fifth larger than that
from Cyprus, and the pattern of the teeth in the Maltese form differs
from that of Cyprus and agrees closely, except in size, with the
living H. amphibius; they cannot, therefore, be referred to the
same species.
Dr. Forsyth Major also compares the Cyprus Hippopotamus with
one from the lignites of Casino (Tuscany), and also with one from
the Wadi-Natrun, described by Dr. C. W. Andrews. They are larger
in size than the Cypriote specimens and present other differences ;
the Casino specimen, in particular, being hexaprotodont in its
dentition. Strange to say, a perfect counterpart both in shape and
size to the Cyprus specimen is presented by Cuvier’s “ petit Hippo-
potame fossile” (H. minutus, Blainv.), a species of Hippopotamus
which resembles in miniature the living hippopotamus, but which
does not surpass the size of a pig, the locality of which was, alas!
unknown, Cuvier having found the specimen in the basement of the
Paris Museum without any label to record its origin. He after-
wards received some identical remains from a private collection in
Bordeaux, and from the Cabinet d’Histoire Naturelle of a M. Decken
in Brussels. Whilst admitting the absolute identity of the Cyprus
teeth collected by Miss Bate to-day with those described a hundred
years ago (but without a locality) by Cuvier, Dr. Forsyth Major
points out that in all stages of their growth they differ most
specifically from the living H. amphibius. Cuvier’s specimens
244 Dr. H. Woodward—On Cave Hunting.
certainly did not come from Dax, and Dr. Forsyth Major concludes
(after careful comparison) that they may have been brought from
Cyprus. It is very interesting, archeologically, to find that at the
end of the seventeenth century the ossiferous breccias at Chrysostomo,
near Kythrea (Hagia Marina), in the district of Nicosia, where
Miss Bate obtained some of her collection, were looked upon as
sacred relics which the Greek inhabitants worshipped, and that
these very bones of the pigmy hippopotamus were passed off upon
the pious as those of their saints! and were thus accidentally
introduced to the attention of Cuvier and De Blainville a hundred
years ago!
A still more interesting discovery has rewarded Miss Dorothy
Bate’s labours in the bone-caves of Cyprus, namely, the discovery
of a new species of pigmy elephant in the same ossiferous deposits
which contained the pigmy Hippopotamus minutus. But we will
allow Miss Bate to tell the story in her own words.!
“While still in Cyprus the receipt of a grant from the Royal Society
in April, 1902, enabled me to devote a considerable amount of time
not only to making more extensive excavations in some of the caves
previously found, but also to a search for further cave deposits. I con-
fined my attention chiefly to the Keryina range of limestone hills in
the north of the island, in the hope of finding bone caves containing
other remains than those of the pigmy Hippopotamus, of which
Dr. Forsyth Major has already given a short description? from
specimens discovered by myself.
“In this search I was at length successful, although it was not until
a certain amount of tentative digging had been carried on in four out
of five newly discovered deposits that work was started on what
appeared at first to be the most unpromising looking place which had
been found, and was consequently the last to receive attention.
“However, during the first day one of the workmen found, not
far from the surface, part of a tooth which was at once recognised as
being that of an elephant. After this discovery every effort was made
to procure a complete collection of the remains of this species, but at
no time were either teeth or bones found to be so plentiful as those
of Hippopotamus minutus, with which they were associated.
“Often not a single proboscidean tooth would be obtained during
two or three days’ work, and only eleven molars and parts of molars
were procured as the result of three weeks’ digging. It was then
decided to continue excavations here for a short while longer, and
this was done until the end of July, work being again resumed in the
beginning of the following October.
«¢ Altogether a good series was obtained of the teeth of this elephant,
which is found to be a pigmy species. With the exception of the
first milk molar (m.m. 2), specimens were procured of all the milk
1 “Preliminary Note on the Discovery of a Pigmy Elephant in the Pleistocene of
Cyprus.’’ By Dorothy M. A. Bate. Communicated by Henry Woodward, LL.D.,
F.R.S., F.G.S., V.P.Z.S., late Keeper of Geology, British Museum (Natural
History). Read May 7, 1903. Proc. Roy. Soc., pp. 498-500.
2 Proc. Zool. Soc., June 3, 1902.
Dr. H. Woodward—On Cave Hunting. 240
and permanent molars of both the upper and lower jaws; also a number
of tusks of different sizes, though these included none of the tiny milk
incisors. No teeth which could be referred to very aged individuals
were obtained, for amongst the last true molars none have more than
half their full number of plates in use.
“The series of teeth consisting of specimens of very anal size, it
was natural in the first instance to compare them with the remains
of the dwarf species from the Pleistocene deposits of the caves and
fissures of Malta and Sicily. It was thought probable that they
would differ from these, the fact of the pigmy hippopotamus
of Cyprus being distinct from those found in the other large
Mediterranean islands lending colour to the supposition; this
expectation was fulfilled, for the Cyprus fossils do not appear to be
identical with any of the Maltese species, though they seem to come
nearest to Hlephas melitensis both in size and in the number of
plates in the molars. The number of these plates in any particular
tooth is liable to vary to a certain extent, but on taking the average,
as far as this can be judged from the amount of material available,
the resulting ridge formula, exclusive of talons, is
7-8 8 9 12
ce 889 12
which practically agrees with that of Z. melitensis given by
Dr. Falconer.'
“The teeth of the Cypriote elephant are considerably smaller than
those of E. mnaidriensis, from both Sicily and Malta, this being the
largest species from the last-named island. They also differ some-
what in their ridge formula, which is that mentioned above, while
Dr. Leith Adams? gives that of Z. mnaidriensis as
3 6 8-9 8-9 10 12-13
3 6 8-9 8-9 10 12-138
“The Cyprus form seems to have been also slightly inferior in size
to E. melitensis, for its largest upper and lower molars do not equal,
either in length or breadth, some of the specimens of the corre-
sponding teeth of this Maltese species which are in the collection of
the British Museum. Its tusks differ from all those from Malta in
being compressed laterally, which character is especially noticeable
in those of the female and young; further, they appear to be more
strongly curved than those of E. melitensis.
‘As a general feature it may be said that the molars from Cyprus
are, on the whole, more simply constructed than those of E. melitensis.
They show a still slighter tendency to ‘crimping’ in the bands of
enamel, and are less inclined to develop the mesial expansion of the
plates of dentine which is not uncommonly found in the teeth of
#. melitensis, and is so conspicuous in those of EH. Africanus.
‘Tt is well known that when the plates of an elephant’s tooth first
1 Pal. Mem., vol. ii, p. 298; London, 1868.
2 Zool. Soc. Trans., vol. ix (1874), p. 112.
246 Dr. H. Woodward—On Cave Hunting.
come into use, the edging of enamel is in the form of a series of
rings owing to the digitation of the plates. These are later worn
into a single band surrounding the enclosed area of dentine.
“Tn the Maltese specimens it is not uncommon to find the encircling
enamel persisting thus divided for a considerable time. Hven four
or five ridges may remain in this condition at one time in a single
tooth, with perhaps an anteriorly decreasing number of rings. This .
is well shown in a tooth, now in the British Museum collection,
doubtfully ascribed by Mr. Busk! to the first upper true molar of
£. Falconeri. This is not so much the case in the Cyprus specimens,
in which the bands of enamel only remain thus separated into
several annuli for a very short while after the plate comes into wear.
“The molars vary considerably, some specimens having very broad
crowns, while others are somewhat narrow. ‘The bands of cement
are wide, in perhaps the majority of cases almost, or quite, equalling
in width the plates of dentine; this seems to be the exception and
not the rule in the molars of H. melitensis. 3
“Taking into consideration the several characters in which the teeth
of the Cyprus elephant differ from those of all the hitherto described
dwarf species (putting on one side HE. lamarmore? from the Pleistocene
of Sardinia, the teeth of which are unknown to science) as well as
the distinct habitat of the animal, I have come to the conclusion that
it is specifically distinct from these other small forms, though possibly
they were derived from a common ancestor, and I therefore propose
to name it Hlephas cypriotes.
“The discovery of the remains of this pigmy elephant, as well as
of Hippopotamus minutus, in Cyprus, is interesting in comparison with
the dwarf species from Malta and Sicily, and because the presence of
an extinct mammalian fauna in this locality had not previously been
recorded. The occurrence of these different, though apparently closely
related, races of small elephants in widely separated islands of the
Mediterranean, lends probability to the theory that this is a case of
independent development along similar lines, the result of similar
circumstances and environments. Nevertheless, it would perhaps be
wise not to take it for granted, without further evidence, that this
diminutive size is wholly and entirely due to specialisation.” (Proc.
Royal Society, May 7, 1903, pp. 498-500.)
Miss Dorothy Bate hopes to be able to communicate a more detailed
account, with figures and full descriptions, of the collection of
elephant remains from Cyprus. We also learn that she will shortly
read a note upon a new species of extinct Genet from Cyprus at the
Zoological Society of London.
It is to be hoped that this is but the commencement of a very
successful scientific career for the author, who has evidently given
her best energies to this most interesting and attractive line of
investigation.
! Zool. Soc. Trans., vol. vi, p. 295, pl. liii, fig. 9.
2 Dr. Forsyth Major, ‘‘ Die Tyrrhenis ”: Kosmos, vol. vii (1883), p. 7.
R. I. Pocock—A New Carboniferous Arachnid. 247
II.—A New Carponirerous ARACHNID.
By R. I. Pocock, F.Z.S., of the British Museum (Natural History).
Introductory Remarks.
AST April Dr. Anton Frié, of Prague, applied to the Natural
History Museum for the loan of a fossil Arachnid which he had
seen during a short visit to London in the Summer of 1902, and
wished to include in a descriptive monograph of Carboniferous
Arachnida which he has now in preparation. Since the specimen
is unique, it was unfortunately impossible to accede to the request.
Dr. Smith Woodward, however, kindly suggested that I should
examine the specimen and, if necessary, describe and figure it, so
that perchance an account of it might yet be in time to find a place
in the monograph above referred to. The specimen, imbedded in the
two pieces of a split nodule of clay-ironstone from the Carboniferous
measures at Coseley, near Dudley, belonged formerly to the collection
of Mr. Henry Johnson. It bears the register number 1551, and is
ticketed by Dr. H. Woodward “Zophrynus, sp. nov.” The dorsal
surface is exposed, part of it adhering to one face of the matrix,
part to the other.
1.—Description of the Specimen ; its generic and specific features.
The carapace unfortunately is crushed, and nothing positive can
be affirmed as to its structure save that it appears to have been
slightly wider than long, with a shallow, postero-lateral con-
striction and a straight, transverse, posterior border. In the middle
line behind, however, there is an acutely angular impression,
obviously representing the median impression occupying the same
position and presenting much the same form in Hophrynus presivicit,
H. Woodw.! The crushed condition of the carapace suggests that
its median area was axially elevated as in the last- mentioned
species and in Kreischeria wiedei.2 Had it been flat or but
slightly convex as in Anthracomarius, the details of its structure
would have been preserved, if we may judge from the state of
preservation of the relatively depressed abdominal area. It is
justifiable, therefore, to conclude that the carapace was constructed
essentially as in Hophrynus and Kreischeria, approaching in particular
that of the former in the smallness of the posterior flattened area
and the shortness of the median muscular impression. It was, how-
ever, less expanded at its postero-lateral angles, and occupied in this
respect a stage of development midway between that presented by
the carapaces of these two genera.
The appendages show no new morphological features. None of
them are complete. Of the first and second pairs nothing is left but
undecipherable fragments. On the right side three of the legs, which,
from their position, I judge to be the first, second, and fourth, are
fairly well preserved. The basal segments (coxa and trochanter) are
1 See H. Woodward, Grou. Maa., 1871, pp. 386-388, Pl. XI, and R. I. Pocock,
Grou. Mac., 1902, p. 490, Fig. 1, A.
2 See Haase: Zeitschr. deutsch. geol. Ges., xlii (1890), pl. xxx, fig. 6.
248 R. I. Pocock—A New Carboniferous Arachnid.
very vaguely defined, but the femur, patella, tibia, and protarsus of
the first and second pairs can be easily made out. They resemble
those of Hophrynus prestvicit in being grooved, but are hardly
noticeably pitted. In the fourth leg the femur, patella, and most of
tg.to------ ARIE >
,
;
:
;
:
to.9-
Fie. A.—Anthracosiro woodwardi, gen. et sp. nov. xX about 23. The lateral
laminz on the second, third, and fourth abdominal segments are relatively
larger than seen in the specimen, and the angular projection of the tergal
plates abutting against the antecedent lamine a little too far back.
Fic. B.—Emended figure of the posterior extremity of the ventral area of Hophrynus
prestvicii, showing the division of the anal tubercle into a tergal (#7. 10) and
sternal (st. 10) element ; ¢g. 9 and st. 9, tergal and sternal area of annuliform
preanal somite; s¢. 8, sternal area of eighth somite ; tg. 8, median and lateral
lamina of the dorsal area of the same.
the tibia are shown.’ On the left side part of the femur of the fourth
projects from beneath the abdomen, and half the femur, the patella,
and the greater part of the protarsus of the second are likewise visible.
From the width of the carapace and the extent to which the basal
segments of the appendages are left uncovered by its lateral borders,
1 This appendage lies in a more vertical plane than the others, being thrust back
partly over the abdomen. In the annexed figure what is to be seen of it has been
drawn in a horizontal plane so that the structure of the abdomen is not concealed.
R. I. Pocock—A New Carboniferous Arachnid. 249
it may be inferred that the sternal area of the cephalothorax (prosoma)
was wide, as in Hophrynus.
The opisthosoma (abdomen) shows very distinctly eight, and only
eight, plates on its upper side. It thus resembles this region in
Kreischeria wiedei, and differs from that of Hophrynus prestvicit,
where nine plates are exposed, the first and second being short
and apparently representing conjointly the first that is retained in
Kreischeria wiedei and in the species now under notice. In the latter
the first is the shortest of the series, the second the longest. The
posterior border of the first is slightly convex in the middle; that of
the others is fairly straight from side to side, although on account of
a distinct and gradual elevation of the median area of the second, third,
and fourth, this border appears from a superficial examination to be
slightly concave in the middle. In the comparative straightness of the
hinder border of the posterior terga, this species differs strikingly not
only from Hophrynus and Kreischeria, but also from Brachypyge and
Anthracomartus, in all of which the terga become progressively more
and more recurved towards the posterior extremity of the abdomen.
In the middle of the terga there is a distinct triangular granular area,
wider behind than in front; there is also a series of fine granules
defining the divisional lines between the terga and their lamine ;
but the tubercles, which form so conspicuous a feature on the terga
and lateral laminze both of Hophrynus and Sreischeria, are here
represented by a single pair of small tubercles upon the terga, and
these are scarcely discernible on the anterior segments. The lateral
borders of the third, fourth, fifth, and sixth terga are slightly produced
anteriorly, and come into contact with the proximal extremity of the
posterior side of the lamina of the antecedent segments. The lateral
laminz, too, are very different from those of the genera of Anthraco-
marti hitherto described. None are visible upon the first; on the
second they appear as slender sclerites lying obliquely backwards ;
on the third and fourth they are of the same form, but larger, and
project back in the same way, and their external margins are bordered
by a strip of chitinous integument belonging to the lateral or ventral
area of the body. It is not until the fifth segment is reached that
the lamin are at all comparable in development to those of other
genera. From the fifth backwards they are large but fairly normal
in size and form, their outer edges forming an evenly continuous
curve. The posterior angles of the laminz of the sixth and seventh
segments, not of the seventh and eighth as in Hophrynus and Krei-
scheria, seem to be furnished with a spiniform process; but upon
this point it would be rash to make a positive statement. The eighth
segment is large, and furnished with the normal median and the
two lateral laminz separated by a deep groove; the lateral laminz,
however, are not marked off from the median area of the tergum, as
is the case in most other Anthracomarti known. Owing to the small
size of the anterior laminz and the large size and obliquely backward
direction of those at the posterior end of the abdomen, this region of
the body is much longer in proportion to its width than in most
Anthracomarti. The impression of the circular anal plate, omitted
250 R. I. Pocock—A New Carboniferous Arachnid.
from the drawing, is plainly visible through the eighth po
near its anterior border.
The principal measurements in millimetres of the type- specimen are
as follows :—Total length 21, length of carapace 6, width 7 (approx.) ;
length of abdomen 15 ; greatest width 10; width i in front 6°5.
The characters enumerated above, though proving incontestably
the right of the species to a place amongst the Anthracomarti
near Hophrynus and Kreischeria, show no less clearly the impossi-
bility of associating it with either of these genera. And since it is
not intermediate between these or any two genera known, but differs
strikingly from all in certain well-marked features, it becomes
necessary to erect a new genus for its reception. This I propose
to name and diagnose as follows :—
Gen. ANTHRACOSIRO, nov.
Carapace and appendages of prosoma constructed apparently as in
Hophrynus, having the posterior horizontal area and the median
impression short. Optsthosoma consisting of eight tergal plates on
its upper surface, as in Kreischeria, but the anterior and posterior
border of all the plates transverse and subparallel, and not becoming
progressively more and more recurved towards the hinder end of the
_ body, as in Hophrynus, Kreischeria, etc. All the lateral laminz
directed obliquely outwards and backwards: those of the anterior
segments in the form of narrow sclerites, overlapped externally by
the chitinised subjacent integument; those of the posterior segments
large. In Kreischeria and Hophrynus all the lamine are large and
subsimilar in size and shape.
The generic name for this Arachnid is suggested by the geological
formation in which the fossil was found, and by its affinity, remote
though it be, to the existing Opilionid genus Siro.
The typical and only known species of this genus I propose to
name Anthracosiro woodwardi, sp.n., dedicating it to Dr. Henry
Woodward, F.R.S., as a slight tribute to his valuable contributions
to our knowledge of fossil Arthropoda. The specific characters of
this species are enumerated with sufficient detail in the description
of the specimen already given.
2. Further remarks upon the morphology of the Anthracomarti.
While working out this new Arachnid, I examined a cast of
Hophrynus prestvictt, which I did not see previous to the publication
of the description of this fossil in the Gronocican. Macazine for
October and November of last year. In this cast I notice one little
structural point, of some morphological importance, which was not
sufficiently defined in the others to allow me to speak with assurance
about it. With reference to the anal plate, I said (p. 447): “This
plate has the form of a transversely oval tubercle, and in one of the
casts is marked by an incomplete transverse groove which suggests
the possibility of its consisting of distinct sternal and tergal elements.
If this be the case, the anal somite will resemble that of the Ambly-
pygous Pedipalpi [Phrynide], rather than that of the Cyphoph-
thalmous Opiliones.” This groove is so strongly defined in the new
R. I. Pocock—A New Carboniferous Arachnid. 251
cast that I see no escape from the conclusion that it represents the
anal orifice. Hence the anal somite is complete with respect to its
tergal and sternal elements. In Hophrynus, therefore, eleven terga
and ten sterna can be made out in the opisthosoma. The first tergal
plate, which has no sternal representative, I homologised with the
tergum of the pregenital somite, and the second, with the corresponding
first sternal plate, with the tergum and sternum of the genital somite
in Phrynus or the Pseudoscorpiones. A subsequent study of the
Opiliones, however, has suggested an alternative interpretation of
these plates which divorces Hophrynus from the Pedipalpi and brings
it more into touch with the members of the former order, with which
the structure of the appendages of the prosoma and of the segments
of the opisthosoma forcibly suggests the Anthracomarti to be nearly
related. In Kreischeria, Brachypyge, and Anthracomartus, for instance,
only ten terga and nine sterna seem to be distinguishable in the
opisthosoma, the difference in the number of segments in this region
between these genera and Hophrynus being attributable to the dis-
appearance, either by fusion or excalation, of the first tergal and the
last sternal plates that are traceable in the latter genus. And when
it is remembered that ten terga and nine sterna are also found in the
opisthosoma in the Cyphophthalmous Opiliones, that the tergum of
the eighth forms the posterior extremity of the dorsal surface, and
overlaps that of the ninth, which, with its corresponding sternum, 1s
reduced to an annuliform preanal sclerite, and that the tenth or last
tergal plate has no sternal equivalent, but closes like a valve over the
anus and is encircled in the way just described, exactly as occurs
apparently in Anthracomartus and Brachypyge, it is difficult to doubt
that the segments of the opisthosoma correspond each to each in
the Cyphophthalmi and the genera of Anthracomarti just mentioned..
If this be so, the first tergum and the first sternum in Anthraco-
martus, Kreischeria, and Brachypyge will correspond to the tergum
and sternum of the first post-genital somite in Phrynus. In that case
the genital aperture in the Anthracomarti must have opened in front
of the first sternum, as it does in the Opiliones, and not behind it as
I assumed in my former paper. Hophrynus is peculiarly interesting
in this connection because it appears to be the only known genus of
Anthracomarti that has retained an unmistakeable trace of the genital
somite, unless the suggestion that I made with regard to the first
tergal plate in Anthracomartus vélkelianus and Kreischeria wiedei be
correct.
In view of this new reading of the facts, the explanation of Fig. 1, A,
p. 490, of my previous paper may be emended as follows :—The plate
marked pregen. tg. will be the tergum of the genital somite, and the
plate marked 1 tg. (gen.) that of the first post-genital somite.
This view of the matter was briefly alluded to in my paper upon
the classification of the Opiliones,! and coincides with the explanation
of the morphology of Leptopsalis, one of the genera of Cyphophthalmi,
put forward by Borner six months earlier.?
1 Ann. Mag. Nat. Hist. (7), x, pp. 504-515, December, 1902.
2 Zool. Anz., June, 1902.
252 A. J. Jukes-Browne—The Purbeck Beds
Il]l.—Tue Purspeck Beps or THE VALE oF WaARDOUR.
By A. J. Juxzs-Browne, B.A., F.G.S.
dae paper written by the Rev. W. R. Andrews and myself, pub-
lished in 1894, gave a more complete account of these beds than
had previously been attempted ; we showed that they were divisible
into Lower, Middle, and Upper groups, comparable with those
established by Professor EH. Forbes in the Purbecks of Dorset, and
characterized by the same species of Cyprides. This paper was based
on the joint examination of exposures visible in 1890, though one
of us, being then resident at Teffont, had observed and collected from
these exposures for many years.
In the following year (1895) Mr. H. B. Woodward’s memoir on
the “Middle and Upper Oolitic Rocks” was published, and his
account differed from ours in several particulars, notably as regards
the thickness of beds referable to the three several divisions, as to
the interpretation of the section near Dinton Station, and as to the
total thickness of the formation. We refrained from comment at
the time, partly because we were prepared to accept such corrections
as were based on the freshly cut exposure near Dinton, and partly
because the mapping of the district had not then been completed, and
we were content to wait till this was done, in the expectation that
Mr. Woodward would then reconsider some of the points on which
we were not in agreement with him.
The mapping of the area was completed in 1900 by Mr. C. Reid,
and this year (1903) the map (Sheet 298, new series), together
with an explanatory memoir prepared by Mr. Reid, have been
published. I am sorry to find, however, that the account of the
Purbeck Beds in this explanation is merely a reprint of that given
by Mr. Woodward in 1895, without any alteration, and with only
‘some small additions by Mr. Reid. As the Geological Survey has
failed to take advantage of this opportunity for revision, and as
silence on our part might be understood as an admission that no
such revision was necessary, I think it desirable to discuss some
of the points in which our account differs from that given by
Mr. Woodward. On some of these questions Mr. Andrews and
I are disposed to modify the opinions expressed in 1894, but on
others we continue to think that our views and observations are
correct. We regret that it has not been possible for all concerned
to meet on the ground, for we think that if this could have been
arranged we should have come to an agreement on most, if not on
all, the points of difference.
1. The Section at Wockley. —Mr. Woodward’s account of this
section is so different from ours that it is not easy to correlate the
one with the other; but one point is clear, that he does not take the
same plane of division between the Portland and Purbeck Series
as we did. In this matter I am obliged to maintain that our
account of the succession is not only fuller but more accurate than
Mr. Woodward’s, for he has not sufficiently distinguished between
of the Vale of Wardour. 253.
the several beds at and near the junction of the two formations.
That this is so will be apparent when the two descriptions are
placed side by side (as below), but in order to indicate the correlative
beds more clearly I have taken the details of the Portlandian part
of the section from my notebook, in which the separation of the
beds composing this series was fully noted.
Our account. Mr. Woodward’ s account.
ft. in.
6. Laminated brown and grey clay, with Dark shaly clay, much squeezed
patches of black clay 0 4 up in places.
5. Hard whitish chalky limestone with
Cyprids, and a layer of cherty stone
with small lenticles of flint at the top 3
4. Soft grey and white laminated marl... 0 6
3. Hard flagey limestone with black flints
at the top, passing down into chalky
Compact limestones, 2 feet.
and shelly limestone .. 2 3 | \ Bed of Roach, with lenti-
2. Rubbly chalky limestone full of large - cular mass of chert at
Pectens, with marked planes at top top. 10 to
and at base... 10 15
bedded, with Portland
fossils.
Bed No. 3 of the above succession is made up of two parts: the
lower foot is a fairly compact, white chalky limestone, crowded with
the shells of Pecten lamellosus; the upper part is a flaggy limestone
without marine shells, but containing the Cyprides Candona ansata
and C. bononiensis, which are marine and estuarine species: these two
beds are closely welded together, they project beyond the others
and usually break away in one block. Mr. Woodward follows
Fitton and others (who considered the flaggy stone to be a fresh-water
bed), and takes the plane along which they can be separated as the
line of division between the Portland and Purbeck Series. We,
having Professor Rupert Jones’ assistance in determining the
Cyprides, recognized the flaggy bed as of estuarine origin, and
finding a marked plane at its summit, preferred to regard it as the
topmost bed of the Portland Series.
I am quite prepared to admit that the beds which are welded
together do contrast strongly in lithological character, and if this
same kind of junction prevailed throughout the district, it would be
a matter of small importance whether the one plane or the other
were taken as the division between the two formations. It is
well .known, however, that in the Chilmark quarries (only two
miles distant) there is a completely different development of beds
at this horizon; at that place there are 16 feet of oolitic limestones
between the top of the chalky limestone and the bed which is taken
as the base of the Purbeck Series. I have suggested that the flaggy
part of the ‘junction bed’ at Wockley is a reduced representative
of these oolitic limestones, for if it is not so, then it is certain that
these limestones can have nothing to represent them at Wockley,
and in that case one would have expected to find a very well-marked
plane of division between the Portland ‘chalk’ and the base of the
Purbeck Beds.
1. Chalky limestone with Portland fossils 13 0 Chalky limestones, obliquely | feet.
254 A, J. Jukes-Browne—The Purbeck Beds
Mr. Woodward rejects our view with the remark that, “‘to be
consistent, however, we must continue to regard the old plane of
division as the best, and going again to the district with Mr. Strahan
no difficulty was found in determining this junction in the quarries
near Tisbury and Chilmark.” This strikes me as an extraordinary —
statement, for I cannot see where consistency comes in, and it is
quite impossible to determine the same junction at Wockley and at
Chilmark.
In all such cases where difference of opinion can arise, unless the
main facts and features of the exposure are fully described, and
unless the thickness of each separate bed is given, with a record of
such fossils as come to hand, students who cannot visit the locality
themselves are unable to form anything like a correct picture of
the section. With this object we give in the Figure a diagrammatic
representation of that portion of the quarry-face which includes the
beds above mentioned.
By 1 Section at WockKLEY.
Base of confused beds.
Brown and dark grey clay.
Hard whitish limestone with Cyprides.
White laminated marl.
Hard flaggy limestone with black flints at top, Candona, etc.,
welded on to the top of
Chalky limestone, full of the shells of Pecten lamellosus.
Parting.
Rubbly chalky limestone, with Pecten lamellosus.
Parting.
bo
)
Chalk of usual type with fossils, but no flints.
2. Division of Lower and Middle Purbecks.—The best exposure of
this junction is in the quarry at Teffont, and of this section a full
account was given by Mr. Andrews and myself, for he had watched
it for many years and had obtained many fossils from the different
beds therein exposed. We found Cypridea fasciculata (var. of
granulosa) abundant in the ‘ flagstone bed’ and in the shale above
that bed, while in the clay below it was less abundant and was
associated with C. purbeckensis. This clay-bed may therefore be
taken as the junction of the two groups, and it would not matter
whether it were included in the one or the other. Mr. Woodward,
however, includes the flagstone and some of the overlying beds in
the Lower Purbeck, putting the plane of division at the base of the
calcareous shale or shaly limestone, which is full of a small Modiola.
of the Vale of Wardour. 255
Mr. Woodward gives no reason for his grouping of the beds; he
does not dispute our record of C. fasciculata, though he does not
quote it, and here, therefore, the question of consistency certainly
does arise, for the accepted divisions of the Purbeck Series are based
on the successive appearance and prevalence of the three species of
Cypridea, C. purbeckensis, C. granulosa, and C. punctata, and any
writer who accepts this basis of classification should be consistent
and should not group beds as Lower Purbeck when their prevalent
Cyprid is C. granulosa.
If Mr. Woodward preferred to adopt some other criterion he might
have explained his reason for abandoning that of the Cyprides; it
may be only a coincidence that his Lower Purbecks include all the
so-called ‘ Lias beds,’ but it is conceivable that he preferred to group
together beds of similar lithological character rather than be fettered
by the range of a single small Crustacean. In that case, however,
“‘to be consistent” he should have made a similar alteration in the
grouping of the Lower and Middle Purbecks of Dorset; it is not
satisfactory to have one method of classification for Dorset and
another for Wiltshire.
I see no reason for any departure from Forbes’ convenient
method, and consequently I maintain that the Middle Purbeck
group in the Vale of Wardour is much thicker than Mr. Woodward
makes it. In his table on p. 267 he gives the thickness of Middle
Purbeck Beds as only 12 feet, but he has apparently based this
estimate on his section of the railway-cuttings west of Dinton
given on p. 274. In this section he has referred the lowest beds
exposed to the Lower Purbeck, but I believe he is quite mistaken
in such a correlation. His ‘brown sandy limestone’ No. 1 repre-
sents the ‘shaly limestone,’ which he takes as the base of the
Middle Purbeck in Teffont quarry, and the whitish limestones above
are the equivalent of the ‘White Bed’ in that quarry. I write
confidently of this because there are similar beds in the next cutting
on the railway (south of Teffont), and their combined thickness
there (4 feet) is rather more than the beds on the same horizon
west of Dinton (where Mr. Woodward’s measurement makes them
3 feet 9 inches).
With the above correction, Mr. Woodward’s restricted Middle
Purbeck would be about 15 feet thick, but when the group is
carried down to the base of the shale below the ‘flagstone’ in the
Teffont quarry, as I consider it ought to be, its total thickness is
a little over 22 feet.’
3. The Upper Purbeck Group.—The existence of this group in the
Vale of Wardour was denied until the publication of our paper in
1894, though the Dinton cutting, in which the lower part of the
group is exposed, had been open for many years, and if anyone had
taken the trouble to collect Cyprides from the beds and to submit
them to an expert like Professor Rupert Jones, he would have
1 T admit an error in our computations of thickness on p. 66 of Quart. Journ. Geol.
Soc., vol. u, due to our having counted in twice beds which we now recognize to be
the same.
256 A. J. Jukes-Browne—The Purbeck Beds
learnt that they contain plenty of Cypridea punctata without oie
C. granulosa.
In 1890 this cutting was partially grassed over, and the rales
of the beds seen in it to those in the next cutting were not clear.
The publication of our account induced Mr. Woodward to visit the
place again, and he was fortunate enough to find that the cutting
had been freshly widened so that the succession could be clearly ©
seen; further, by digging below the level of the rails, he carried
his measurements down to the Archgoniscus bed. Some of these
beds were admitted by Mr. Woodward to be of Upper Purbeck age,
but the greater part of what we had regarded as Upper Purbeck
was referred by him to the Wealden.
With respect to the beds seen in the cutting, I accept the fresh
evidence obtained by him: I agree with him as to the plane of
division between the Middle and Upper Purbeck groups, and admit
that there is no necessity for the hypothetical faults which we had
introduced. I have no reason to doubt his measurements of the
beds in the middle of the anticline, but think that the sand and
clay at the base of the Upper Purbecks must thicken to the west-
ward. Some of the sand which I saw at the eastern end of the
second cutting may have been rearranged, but I do not think there
was less than 6. feet of it in siti, or less than 4 feet of the clay
below. This view is confirmed by the section in the deep cutting
south of Teffont (not described by Mr. Woodward); we gave
a complete account of the beds therein exposed, and it is now quite
clear that they include the base of the Upper Purbeck. The highest
beds seen are as follows :—
ft. in.
Wet grey and yellow sand ing HB ae, 30r4 0
Light-grey sticky clay 09 LS
Soft marly clays with thin brown iron- stained layers ae 2 0
Light buff-coloured marl . as ret 0 4
Hard whitish grey- ~hearted silty limestone i @
The limestone is clearly the same as that taken at the top of the
Middle Purbeck in the Dinton cutting, and there is here 4 feet of
marl and clay above it, succeeded by more than that thickness of
sand. Mr. Andrews and I also saw the same limestone in the next
cutting (south-east of Chicksgrove Farm), overlain by grey and
yellow clay, brown sand and sandstone, and a gravelly soil, but.
these upper beds were confused by slipping; they are clearly
a remnant of the outlier of Upper Purbeck subsequently mapped
by Mr. Reid north-west of the Farm.
The basal part of the Upper Purbeck group being now established,
there remains the question of its upper limit, and this we admit to
be difficult of settlement. Mr. Woodward draws the line between
Purbeck and Wealden, quite arbitrarily, at a thin layer of sand seen
in the cutting about 10 feet below the surface of the ground. Of
the beds thus referred to the Wealden Mr. Reid remarks, ‘In the
Dinton cutting only some ten feet of the lower part of the Wealden
Beds can be examined, and the exact age of these deposits is perhaps
not quite satisfactorily made out.” He thus admits that their age
of the Vale of Wardour. | 207
is a matter of opinion, and I can understand that as he and
Mr. Woodward were obliged to draw a line somewhere for de-
lineation on the map of the Geological Survey they gave the Wealden
the benefit of the doubt.
Mr. Andrews and I considered these beds as a continuation of the
Upper Purbeck, and we obtained fossils from the material thrown
out of a well sunk at the cottages near Dinton Station; it is true
that most of the species found range from Purbeck to Wealden, but
they included Cypridea punctata, which has not yet been recorded
from Wealden. The well is 40 feet deep, and the fossils probably
came from less than 30 feet down. How much of this thickness
is Purbeck and how much Wealden is evidently a matter of opinion
and extremely uncertain. The following may be given as a summary
of the beds which lie between the Lower Greensand and the Middle
Purbeck, near Dinton, with estimated thicknesses :—
feet.
4. Yellow and grey silty clays by Dallwood Farm ... 15-20
3. Grey silty marl (in the well) . =. | LO=12
2. Stiff grey and yellow clays (in the well and cutting). : 25
I. Marls, shales, and grits (in the cutting) Se Be 12
No. 1 is Upper Purbeck; No. 2 may be either Purbeck or Wealden ;
Nos. 8 and 4 are probably Wealden.
4. Purbeck and Wealden at Teffont.— When in 1890 Mr. Andrews
and I endeavoured to trace the Upper Purbeck and Wealden clays
towards Teffont we found that their thickness became very much
less, and that the space occupied by their outcrop north of Teffont
Rectory was very narrow. We found there exposures of the following
beds in descending order :—
D. Black clay.
C. Greenish-black glauconitic sand.
B. Mottled clay, white, yellow, and claret-coloured, like the ‘ cat’s-brain’
clay of Kentish Wealden.
A. Yellow silty clays.
The upper two members of this succession we regarded as Lower
Greensand (Vectian), the lower two as Wealden, believing A to be
part of the Dallwood Farm beds, No. 4 of the series near Dinton.
We saw nothing between this and the Middle Purbecks, and there
did not seem room for the Upper Purbecks (Nos. 1 and 2) to come
in, so that we concluded the Wealden had here overlapped the
Upper Purbeck Beds.
From the newly issued 1 inch map I find that Mr. Reid does not
carry the Wealden clays so far west as the point where we saw the
above succession, but has coloured all the beds north of the Rectory
between the Middle Purbeck and the Vectian Sands as Upper
Purbeck. It is clear, therefore, that Mr. Reid agrees with us in
thinking there is not room enough here for the whole thickness of
Upper Purbeck and Wealden, but differs from us in regarding the
beds which de occur as Purbeck instead of Wealden. In the
explanation of the map (Sheet 298) he does not describe any
exposure of these beds north of Teffont, either under the head of
Purbeck or Wealden, but quotes our description of them in his
DECADE IV.—VOL. X.—NO. VI. 17
208 A. J. Jukes-Browne—Purbeck Beds, Vale of Wardour.
chapter on the Lower Greensand, and then remarks that he doubts
our correlation of the clays at Dinton and Teffont.
Here, again, therefore, it is a matter of opinion, and those
responsible for the published mapping of this bit of ground do not
seem able to give very good reasons for their beliefs. We suppose
Mr. Reid correlates the yellow silty clay of Teffont with the yellow
grey and white clays at the top of the Dinton cutting, but in the
latter place there is nothing like the peculiar ‘cat’s-brain’ clay, and
until some one can find that kind of clay in the Upper Purbeck of
the Vale of Wardour I shall continue to regard it as belonging to
the Wealden, and to believe that Mr. Reid has not carried the
Wealden far enough to the westward along the northern side of
the Vale.
When describing the Purbeck Beds in 1894 we incidentally re-
marked that there was a complete discordance between the Purbeck
Beds and the Lower Cretaceous Series, ‘“‘including the Wealden.”
This was carelessly expressed : the great unconformity is undoubtedly
at the base of the Lower Greensand, but we certainly did think that
the Wealden overlapped the Upper Purbeck. Whether it really
does so depends on the correct separation of the Wealden from the
Purbeck. The bare idea of a break at the base of the Wealden
fluttered the dovecotes of Jermyn Street to such an extent that the
question seems to have assumed proportions of paramount importance
in the minds of Messrs. Woodward and Reid. Others, however,
may deem it of equal importance that the divisions of the Purbeck
Series should be established on logical grounds, that the thickness
of each group should be carefully estimated, and that the outcrop of
the Wealden Beds should be carefully discriminated from that of the
Upper Purbecks.
Finally, Mr. Reid’s reference to Endogenites erosa adds nothing to
the strength of his position. He admits that “it is too doubtful
a form to be of much value for correlation,” but immediately adds,
“though its presence supports the view that the strata containing it
truly belong to the Wealden period, and are not, as supposed by
Messrs. Jukes-Browne and Andrews, of Purbeck age.” He quite
ignores the fact that we found a large piece of similar endogenous
wood in the Upper Purbeck sand of the Dinton cutting. It is also
a fact that pieces of Endogenites erosa have been found close to the
spots where outliers of the Upper Purbeck are shown on the map,
and when it is remembered that the fossil wood has never been
found in the beds referred by Messrs. Woodward and Reid to the
Wealden, it will be apparent that the facts are much more in accord
with our view than with Mr. Reid’s.
In conclusion, I may place on record that I have submitted one
of the surface fragments to Mr. A. C. Seward, and he kindly informs
me that he believes it to be the true Endogenites erosa, now known
as Tempskya Schimperi, and in reality the stem of a tree-fern. Un-
fortunately, I could not send him a piece of the wood found in the
sand at Dinton, and cannot therefore affirm that it was also Tempskya,
but it was so similar that I took it to be the same.
C. T. Clough—Disappearance of Limestones, High Teesdale. 259
I append a revised estimate of the total thickness of the Purbeck
Beds in the Vale of Wardour, if the Upper group is to be restricted
within the limits indicated by Mr. Woodward.
i TM, =
Mean thickness from top of No. 30 to base of limestone Up :
with Unio (part of 21) a60 a a coo «6 Pp ee
Yellow sands with Endogenites ... “e ae os) =. 0 aot a y
Grey clays and marl bE 4 0 ae
Thickness from top of No. 19 to top of the Arehoniscus
bed (No. 13) 7 01} wiadle
From top of No. 19 to top of cinder bed (south of P b yk
Teffont) ; 4 3 ee : ie fe
From top ot cinder bed to base of the ‘scale’ below Tea
the flagstone at Teffont ... il» ©
From base of ‘scale? to marl-band below the 5th Lias 15 9
Section in Ridge quarry from marl below ‘ Lias’ to Lower
bottom of quarry ... a one z.- L9 10) - Purbeck,
Allowance for gap between quarries bes 7 0] 643 feet.
Section at Wockley from surtace to base of Purbeck Beds 22 0
Total Bae oe ... 108 10
YV.—TuHe DIsaPpPpEaARANCE oF Limestonges IN HicH Trespate.!
By C. T. Croveu, M.A., F.G.S., of H.M. Geol. Survey.
N High Teesdale, on certain hillsides, the structure of which is in
most respects clear, the observer is struck by the disappearance
of some, generally constant, limestone which ought naturally to
occur. The limestone most usually missing is the Great Limestone,
which, with the exception of the Melmerby Scar Limestone, is the
thickest of all in the dale. Though the ground is almost free from
peat and drift, and plainly shows the banks formed by the Four
Fathom Limestone and Firestone,” there is yet perhaps neither bank
nor ‘shake-hole’ (swallow-hole) to represent the Great Limestone.
In the cases referred to the difficulty cannot be accounted for by
supposing that the limestone along its outcrop is thrown out by
a fault, for the outcrops of the beds above and below can be followed
round the hill without interruption.
Where the limestone disappears many masses of sandstone are
usually found, most of which seem somewhat disturbed; and, in
the small streams, thin irregular bands of soft, rather siliceous, clay
and iron ochre occur. The clay and ochre represent the limestone,
which, in the language of the dalesmen, has been ‘eaten away ’
along the outcrop and replaced by ‘ famp.’
1 The substance of this communication was written 25 years ago. Since then
Mr. F. Rutley has written ‘‘On the Dwindling and Disappearance of Limestones’’
(Q.J.G.8., 1893, vol. xlix, p. 372), but he makes no mention of their special
lability to dwindle in the neighbourhood of faults and veins, and gives no instances
of their disappearance on a lars ge scale. Mr. J. R. Dakyns has written a short paper
“*On ‘ Flots’’’ (Report Brit. Assoc., 1881, p. 634), and the material in many ‘ flots’
seems of much the same nature as ‘famp.? The writer has recently seen an instance
of famping, differing somewhat from the examples in Teesdale, in one of the lime-
stones (the Skateraw Middle Limestone), which has been quarried at Catcraig, near
Dunbar, and this has recalled the subject to him.
2 The Four Fathom Limestone is a little below the Great, and the Firestone is
a sandstone a little above the Great Limestone.
260 0. T. Clough—The Disappearance, or * Famping,’
The best locality for observing ‘famp’ and the accompanying
phenomena is at the Highfield ‘hushes,’* above Grasshill. — It is
there seen in clear section that the Great Limestone, the average
thickness of which in the neighbourhood is 55 feet, is replaced by
10 or 12 feet of soft siliceous, irregularly banded, ochreous. clay.
Several veins cross the hushes, and near these veins low rambling .
levels have been driven in search of lead ore. Such work gives
rather uncertain returns, for there are no straight or constant strings.
of ore to follow, but every here and there nodular masses of ore,
occasionally a foot or more in breadth, are met with, which seem on
the whole to repay the miners. These masses often occur together
in groups, the centre of the larger examples being composed of
galena, and the outside usually of carbonate of lead, or of a mixture
of carbonate, phosphate, and arseniate. In the smaller, those with
a breadth of an inch or less, the mass is often composed throughout
of the three last-mentioned ores without any galena. The outlines
of most of the lumps are rounded, and they show no sharply
defined crystals of galena like those common in the ordinary veins.
The miners think that the famp-ore has been water-worn, and they
are probably right in one sense, though the carbonate and phosphate
of lead, etc., on the outsides of the lumps, are often in well-formed
srystals which cannot have undergone rolling.
A few other minerals, associated with the lead ores in the adjacent
veins, are also found in the famp. Besides these, there are hard
round lumps, each consisting of a limestone centre and an outer
coat, which shows a gradual passage between limestone and famp.
No sandstone boulders have ever been noticed in famp.
It is usually stated that limestones are not so much famped ‘ under
the hill’ as at the outcrops, and the sections at the head of Highfield
hushes seem to confirm this opinion. In the gutter made in 1876
to hush part of the famp, a series of small faults and local contortions
were seen, which bring down the ‘Coal Sills,’ the sandstones next
above the Great Limestone, to lower levels towards the south, the
direction in which the outcrop of limestone should occur. We know
that these disturbances do not affect the beds below the famp, for
they were not met with in the Cowby level. which is driven nearly
under this gutter. They seem due to the dwindling away of the
limestone as it comes near the surface. Famp probably replaces.
the Great Limestone in Yad Moss level, South Lang Tae sike,
Blackway Hole hushes, the West Beck and Old Langdon hushes,
and Pikelaw hushes. It probably also occurs for most of the way
between Blackway Hole and South Lang Tae sike, a distance
measured along the outcrop of about a mile, from the Yad Moss
level to some distance on the north side of Crook Burn, and for
half a mile or more on the north side of Henrake hush.
The areas wherein limestone has been replaced by famp are
sometimes sharply defined. In Pikelaw hushes, vertical walls of
1 A hush is an artificial wash-out, made for the purpose of baring and cutting the
strata and the veins which cross them. In the process of hushing a reservoir is made
high on the hill, and the water is let out in a flood along the desired direction.
of Limestones in High Teesdale. 261
limestone, 20 or 30 feet high, stand (1876) close against sandstone
and shale, but when the margins of the limestone are examined by
hushing, etc., they show no vein, and they do not continue in nearly
straight lines as most veins do. Parts of the limestone stand up
like ruined towers on the floor of Blackway Hole hush, and it is said
they remain much as they were when originally found sticking up in
- amass of famp.
The famp in the Yad Moss level is mixed with irregular streaks
of a black earthy mineral, part of which is probably a black ore of
manganese. In the West Beck and Old Langdon hushes the famp
consists of nearly pure iron ochre, and it would no doubt have been
used for smelting if it had been in a more accessible locality. In
Weardale a famp of similar character has long been largely worked
for this purpose. The light yellow varieties of famp are sometimes
used instead of whitewash, for painting over walls, etc.
The limestones in Teesdale, which, next after the Great Limestone,
are most conspicuously famped, belong to the Melmerby Scar group
of limestones, in the neighbourhood of Silver Band Mine, Cronkley
Fell. These limestones and the Great are generally rather pure
limestones (the Great usually contains about 95 per cent. of carbonate
of lime), so that the famp cannot be solely the residue of their
decomposition. The greater part of it must have been introduced
from without. It is most abundant where veins of ore are most
numerous, and it is probable that most of the famp material was
introduced by the same agent which filled so many of the neigh-
bouring veins with ironstone and other minerals.
Where an ironstone vein passes through limestone, the width of
the vein is nearly always greater than in sandstone or shale, for the
limestone ‘cheeks’ are converted into ironstone for a certain breadth
at the sides of the vein. ‘The ironstone has not only grown in the
open fissure of the vein or fault, but has also replaced part of the
limestone. This is shown by the casts of corals, crinoids, ete., which
are found in the ironstone. In a similar way, also, where a quartz
vein passes through limestone, the limestone on the sides is partly
replaced by finely crystallized quartz.
We suppose that the fissures made in the course of earth move-
ments formed channels for the circulation of water holding various
minerals in solution, and that this water not only deposited minerals
in the fissures, but aiso gradually dissolved part of the limestone it
passed through, and deposited other minerals in its place. The
replacement effected along the sides of the veins varies greatly in
extent, and it is probable that a replacement by carbonate of iron
was the first stage in the manufacture of famp.
But why is the limestone more often dissolved away along the
outcrop than elsewhere? It appears as if the action, which was
first started by water circulating along the veins, had been continued
and modified in recent times, since the present surface of the ground
was developed, and that this later action is perhaps still in progress.
It is obvious that where a limestone was already partly dissolved
away near the outcrop, the ground above would be affected by local
262 Dr. A. Fritsch—The Prague Museum.
faults: and slips, and would be specially liable to penetration by
surface-water, which, already charged with carbonic acid, would
therefore be well suited for dissolving more of the limestone. The
‘same surface-water which dissolved the additional portion of lime-
stone, may also have altered the character of the substances which
were first formed near, or in place of, limestone, partly mechanically,
by rearranging them, and partly chemically, by converting the car-
‘bonate of iron into the hydrated peroxide,’ and galena into other
salts of lead. It would, of course, take longer to completely change
the larger masses of galena than the smaller, and hence in the larger
a centre of unchanged galena still often remains.
It may be noted, in conclusion, that these instances of solution of
limestone on a large scale show one method by which the higher
beds in a series may be faulted and folded while the lower beds
remain undisturbed.
V.—Tue Pat@ontToLoGIcaAL AND GEOLOGICAL COLLECTIONS OF THE
Bonemian Musrtum 1N PRAGUE.
By Dr. Ant. Fritscu.
(PLATE XIV.)
FTER transferring the collections to the new building in the
year 1892, more than ten years work was necessary to finish
the arrangement of 251 cases, which occupy seven large rooms.
‘Now nearly all this labour is completed, and those who are interested
in paleontology will be glad to learn some details as to the general
arrangement of the Museum.
_ All fossils are fixed on tablets, or placed in glass-topped boxes.
The labels are printed on greenish paper, and contain references to
the work and plates where the type- specimens are described and
figured. Beneath very small fossils is fixed a magnified figure
taken from the book” where the species has been published. The
under side of the tablets is used for white labels with further
(written) details, catalogue numbers, etc. The inclination of the
cases is 45° or 60°. Six rooms are devoted to the geology and
paleontology of Bohemia and one large room to the general strati-
graphical collection.
The first room, called ‘ Barrandeum ” (26 metres long’), contains
the famous collection of Barrande, in which are incorporated the
old Museum collection, the collections of Bishop Zeidler, of Corda
and Hawle, and of Professor Novak. In six wall-cases are exhibited
representative specimens of the chief Azoic, or Hozoic, Primary and
pre-Cambrian rocks of Bohemia, on which the younger formations
are deposited. Sixty glazed cases contain the Cambrian, Silurian,
and Devonian fossils, arranged in stratigraphical order. In the
drawers beneath, the specimens are arranged in zoological order in
1’ See Professor J. W. Judd, “‘ Geology of Rutland’’ (Mem. Geol. Sury.), p. 135.
2 See my article in Natural "Science, vol. viii (1896), No. 49.
"ANDVad ‘WNASNW NVINSHOS AVAON SHL
sake
Ru
PINE Wal OX TON UNITE BEVEL "C061 “SVIN “10U45)
Dr. A. Fritsch—The Prague Musewn. 263
such a way that every type-specimen of Barrande’s can be quickly
and readily referred to. Hach case exhibits in its upper part
about 100 objects, and beneath each are 18 drawers (in three rows) of
specimens for purposes of scientific study. A special case is devoted
to the memory of J. Barrande, showing a copy of his monumental
work (28 vols. 4to, containing 1,454 plates, giving illustrations
of more than 4,800 species from the Bohemian Paleozoic Basin) ;
then a photograph of the memorial tablet fixed on the Silurian
rocks near Kuchelbad, and a photograph of the house in which he
resided in Prague during 40 years, together with the tools he used
in developing his fossils, and his portrait when he first arrived in
Bohemia.
The second room, called ‘‘Sternbergeum,” about 100 square metres,
contains the type-specimens of the work of Count Caspar Sternberg,
‘Flora der Vorwelt.” In a central pavilion are grouped about
40 large and striking examples of Carboniferous plants, forming
a pyramid, on the summit of which is placed a bust of Sternberg
in Carrara marble. In two of the wall-cases are placed the Arachnida
and Scorpions of the Coal-measures, 25 species represented by about
60 specimens. .
The third room is a laboratory of phytopaleontology.
The fourth room, 100 square metres, contains the stratigraphical
collection of the Bohemian Coal-measures, with type-specimens of
Feistmantel’s works. Then follows the Permian formation, with the
type-specimens of the work “ Fauna der Gaskohle” by the writer.
The last of the 28 cases shows a rare collection obtained from the
Jurassic beds in northern Bohemia, being the type-specimens of
Dr. Bruder’s work.
The fifth room, of equal proportions, contains the Chalk formation
of Bohemia, displayed in 28 cases. Three cases contain a splendid
exhibition of the Cenomanian flora described by MM. Velenovsky
and EH. Bayer. The marine fossils from different stages (Cenomanian-
Senonian) are here shown as documents in evidence of the mono-
graphs published by myself in the “ Archiv fiir Landesdurchforschung
Bobmens,” exhibited in 25 cases.
The sixth room is devoted to the Tertiary (lacustrine) formation
of Bohemia, and shows in 28 cases a rich flora and fauna (fishes,
insects, mollusca, and a great part of the skeleton of Dinotherium
found near Abtsdorf, and many other mammalian remains).
The last room of the series, devoted to Bohemian geology and
paleontology, contains in 12 cases the diluvial and alluvial fauna,
the vertebrates described by Kafka, and the mollusca by Babor.
There are also exhibited specimens to illustrate the lithological
character of each period. In a central pavilion are displayed the
remains of Hlephas, Rhinoceros, Cervus, Bos, etc. Near the window
is exhibited a complete skeleton of the Rhinoceros found near
Pardubie.
In all the rooms named above are also displayed geological maps
showing the geographical distribution of the formations in Bohemia,
and diagrammatic coloured sections of the principal localities,
264 EF. A. Walford—A Fault at Tainton Down, ete.
accompanied by rock-specimens from each zone or layer of every
formation occurring in Bohemia.
Finally, we come to a large room, 26 metres long, in which is
arranged in 60 cases a general stratigraphical collection. Here are
exhibited for comparison, besides Bohemian specimens, those of
England, France, Germany, Russia, America, etc., giving an adequate
idea of the character of each formation in other countries. Beneath
the windows are placed four table-cases with a general dynamical
collection, with large explanatory labels. Against the wall, upon
two large stands, are exhibited casts of remains of great vertebrates,
and upon the opposite wall hang geological and palzontological
pictures and diagrams.
The scientific work carried on by the staff of the Geological Depart-
ment is as follows :—Gasteropoda of Bohemian Paleozoic Basin (con-
tinuation of Barrande’s work), by Dr. J. Perner ; newer Cretaceous
Plants, by Dr. Hdvin Bayer; Arachnids from the Coal-measures,
by Dr. Ant. Fritsch; Fishes and Reptiles of the Bohemian Chalk
formation, by Dr. Ant. Fritsch and Dr. Bayer; Graptolites, their
geological distribution in Bohemia, by Dr. J. Perner; Tertiary
plants and insects from Bohemia, by the Junior Assistants.
A new guide to the collections is now being prepared. The original
specimens are always accessible to all scientific investigators, but
cannot be sent away to other Museums.
VI.—On a Fautr at tue Foor or Tatnton Downs.
By Epvwin A. Watrorp, F.G.S.
O the north of Tainton, near Burford, Oxon, the 500 o.p. contour-
line passes through the old quarry grounds where the well-
known Great Oolite freestone may be seen dipping at a high angle
to the north-east. The bank falls 100 feet to the brook, 400 yards
distant, where culvert and pipe trenches for new field waterworks
have exposed what may be a continuation of a fault marked on the
one-inch geological map of the Ordnance Survey as following the
course of Coombe Brook, a mile to the north.
The Great Oolite runs half-way down the bank, and is underlain
by a few inches of the pale grey marl of the Fuller’s Earth. The
Fuller’s Earth is unfossiliferous, and recognizable only by its litho-
logical type and horizon. Between the Fuller’s Harth and the
heavy blue clays of the Upper Lias are two or three feet of sandy
limestone, iron-stained, representing the Inferior Oolite. At the
bottom of the trench thick blocks of brown and green ferruginous
limestone are of the Middle Lias (zone Ammonites spinatus), with
the following fossils, Avicula inequivalvis, Pentacrinite segments, and
rolled Belemnites, in a nodule bed, a stratum in North Oxfordshire
well known as the base of the ‘ Marlstone’ of the Middle Lias.
The stone is of the typical Oxfordshire type, close-grained, oolitic,
and of a dark green colour. It gives appearance of a former well-
developed extension over the area. It must not be forgotten,
however, that the Burford Signett boring for coal in 1874 proved
but 3 ft. 6 in. of Middle Lias stone.
Notices of Memoirs—Professor H. A. Miers on Crystals. 265.
In the steep roll of the bank near the brook, in 40 feet, are
represented strata of the
Great Oolite,
Fuller’s Earth,
Inferior Oolite,
Upper Lias,
Middle Lias,
the wasted remnant of a thousand feet of rock and clay of the higher
north-west Cotteswolds.
The dip into the hill on the downs of the Tainton Great Oolite
freestone suggests the probability of a high fault line along the
downs parallel with the low line of fault described. It may be
safely surmised that the curved line of fault mapped by the Survey
joins the one at the Waterworks nearer Tainton, and it is probable
that the upper line of fault meets the long fault seen to be trending
from east to west above Burford and near Waterloo Farm.
ADpDENDUM.—NotTE on THE Microscopic Tyrer or tHE MARLSTONE
or TAINTON.
The stone is of the usual dull green colour, weathering toa reddish
brown. It has the granulated appearance of the bottom stone of
North Oxfordshire, though it is really not of so oolitic a type.
In section it is shown as a mass of ferro-crinoid segments, held
together by a matrix of clear calcite of which but little is seen.
The segments or plates are pentagonal, ovoid, orbicular, or of
irregular shape, and are pierced with rounded openings.
Scattered throughout the mass are olive-coloured patches or
granules of ferrous carbonate, with oolitic grains of the same colour,
of ovoid or irregular shape, and of small size. When solidified
they pass from a pale olive brown to a deeper rich brown colour.
The interspaces and passages of foraminifera and other organisms
are filled with the same mineral. There is no trace of concentric
banding or lamination in the oolitic grains, which appear to be
decomposed rather than fully formed.
It is remarkable that in strata of such great waste the organic
structure of the ferro-crinoid, which I have elsewhere shown to be
the main constituent of the Middle Lias ironstone, should remain,
and that the oolitic stage should be so feebly developed.
IN Ome KG Ass) (ssp VaWwIskaMGO oS S35 Jaa).
An Enquiry into THE VARIATION OF ANGLES OBSERVED IN
CRYSTALS, ESPECIALLY OF PotasstumM-ALUM AND AMMONIUM-
Auum.' By Professor H. A. Mimrs, M.A., D.Sc., F.R.S.
\ORRESPONDING angles measured on different crystals of the
same substance usually differ slightly. On cubic crystals the
theoretical angles are known. Pfatf professed to have established
1 Abstract of a paper read before the Royal Society, March 26, 1903.
266 Notices of Memoirs—Professor H. A. Miers on Crystals.
that only those cubic crystals which display birefringence exhibit
divergence from the theoretical angles, but Brauns showed that
in lead nitrate, ammonia-alum, and spinel, for both isotropic and
birefringent crystals alike, the octahedron angle may differ by as.
much as 20’ from that of the regular octahedron.
The author has endeavoured to trace the changes of angle upon
one and the same crystal during its growth by measuring it at
intervals without moving it from the solution in which it is growing.
This is accomplished by means of a new telescope-goniometer in
which the crystal is observed through one side of a rectangular glass
trough, and the changes in the inclination of each face are followed
by watching the displacements of the image of a collimator slit
viewed by reflection in it. The crystal is held by a platinum clip
which it envelops as it grows. Small movements of the image are
followed by means of a special micrometer-eyepiece which accurately
measures the magnitude and direction of the displacement.
Examined in this way an octahedron of alum (ammonium or
potassium) is found to yield, not one, but three images from each
face; and closer inspection shows that the crystal is not really
an octahedron, but has the form of a very flat triakis-octahedron.
It often happens that of the three faces which nearly coincide, one is
large and the remaining two very small, so that of the three images
one is bright and the others are very faint and can only be discerned
with difficulty ; in such a case the crystal as measured in the ordinary
way would appear to be an octahedron whose angle differs from the
theoretical value by a few minutes.
When a growing crystal of alum is watched for several hours or
days, it is found that the three images yielded by an apparent
octahedron face continually change their position; one set fades.
away and is replaced by another set which are generally more
widely separated than those which they succeed. The images move
in three directions inclined at 120° to each other, and indicate that
these faces always belong to a triakis-octahedron. The point in which
the lines of movement intersect within the field of view of the
telescope would, therefore, be the position of the image reflected
from the true octahedron face. Measured in this way the octahedron
angle of alum is found to be the theoretical angle 70° 31?’
The images do not move continuously, but per saltum, indicating
that the reflecting planes are vicinal faces which probably possess.
rational indices, and must therefore be inclined at certain definite
angles to the octahedron face; but the indices are very high numbers.
Observations upon sodium chlorate, zinc sulphate, magnesium
sulphate, and other substances show that other crystals exhibit the
same behaviour. The faces of a crystal are in general not faces with
simple indices, but vicinal planes slightly inclined to them, and they
change their inclinations during the growth of the crystal ; they also
change their inclinations when the crystal is immersed to a greater
or less depth in the solution.
Every point within a crystal has at some time been a point on
the surface, and has been subject to the conditions of equilibrium
Notices of Memoirs—Professor H. A. Miers on Crystals. 267
between crystal and solution which prevail there. It is betieved
by the author that a study of the vicinal planes and of the liquid
in contact with them, may lead to some understanding of these
conditions.
In order to ascertain the composition of the liquid, attempts were
made to determine its refractive index by means of total reflection
within the crystal. This appears, indeed, to be the only method
which can give direct information concerning the ultimate layer in
contact with the growing face, and it is somewhat remarkable that it
has not been applied before. Considerable difficulty was experienced
in making this measurement, but ultimately good readings were
obtained which gave the value 1:34428 as the refractive index in
sodium light, at 19° C., of the liquid in contact with a growing
crystal of alum. ‘he refractive indices of a series of solutions of
known strength, ranging from dilute to supersaturated, having been
previously measured, the above index was found to correspond to
a liquid containing about 10-80 grammes of alum in 100 grammes
of solution. A saturated solution at 19° C. was found to have the
refractive index 1:34232, and to contain about 9:01 grammes of
alum in 100 grammes of solution.
Sodium chlorate was examined in the same way: it was found
that the liquid in contact with a growing crystal has at 19° C.
the index 1-38734, and contains about 47-8 grammes of salt in
100 grammes of solution; a saturated solution of sodium chlorate
at 19° C. has the index 1:38649, and contains about 47-2 grammes
of salt in 100 grammes of solution.
The liquid in contact with a growing crystal of sodium nitrate
has at 19° CO. the index 138991, and contains about 48:45 grammes
of salt in 100 grammes of solution; a saturated solution at 19° C.
has the index 1:38905, and contains about 48-1 grammes of salt in
100 grammes of solution.
In each case the liquid in contact with the growing crystal is
slightly supersaturated. It was not found to exhibit double re-
fraction even in the case of sodium nitrate. No experiments seem
to have previously been made upon the nature of this liquid.
G. Wulff has suggested that vicinal faces are due to concentration
streams in the solution. In order to test this view, crystals of alum
were measured after growing for several hours in solution kept
continually agitated in order to eliminate the action of the con-
centration streams. Almost no effect was produced upon the angles
of the vicinal faces.
In sodium chlorate and sodium nitrate the solute is about 45 times
more dense in the crystal than in the adjacent liquid. Now planes
with high indices in a space-lattice contain fewer points in unit area
than planes with simple indices. ‘The author suggests that vicinal
faces grow upon a crystal in preference to simple forms because the
crystallising material descends upon the growing face in a shower
which is not very dense.
268 Reviews—Prof. v. Koenen—North German Ammonites.
ay Je Wr At JEN WY (SS -
J.—Norra German Neocomran Ammonites. Die AMMONITIDEN DES
NorppeutscHen Neocom(VALANGINIEN, HAUTERIVIEN, BARREMIEN,
unD Aptizn). By Professor Dr. A. v. Koznen. pp. 451, 55 plates,
and 2 text illustrations. Abhandlungen der Koniglich Preussischen
Geologischen lLandesanstalt und Bergakademie, Neue Folge,
Heft 24, 1902.
ROF. DR. A. v. KOENEN is so well acquainted with the
Neocomian deposits of Northern Germany that we heartily
welcome the present work, which forms the first part of a monograph
of the fauna of those beds. This portion is devoted entirely to
a consideration of the Ammonoids; the Nautiloids, Dibranchs,
Gastropoda, and Pelecypoda being reserved for the second part.
The bibliography of the subject, most carefully prepared by the
author, occupies some eight and a half pages, and gives one some
idea of the amount of literature relating to these deposits. About
15 pages are devoted to the stratigraphy of the Neocomian beds
of North Germany, whilst the description of their Ammonoid fauna
occupies some 360 pages.
In the North German Neocomian beds, that is, in the beds
belonging to the Valanginien, Hauterivien, Barrémien, and Aptien,
that occur. between the Berriasien (= Wealden) and the Albien
(=Gault), the author recognises the following fifteen distinct zones :—
ALBIEN = Gault.
Upper. Zone of Hoplites furcatus, Sow.
jNarnrie », Hoplites Deshayesi, Leym.
; Lower. », Acanthoceras Albrechti Austrie, Hohn., and
Hoplites Weissi, Neum. & Uhlig.
5, Ancyloceras trispinoswm, v. Koen., and Desmoceras
Hoyeri, v. Koen.
»» Aneyloceras innecwm, v. Koen., and Crioceras
Upper. pingue, v. Koen.
BarriMieEn. » Crioceras Andree, v. Koen., C. Denckmanni,
G. Mull., and Ancyloceras costellatwm, v. Koen.
», Crioceras elegans, v. Koen.
Lower. » Crioceras fissicostatum, Roem., and Ancyloceras
crassum, Vv. Koen.
Olcostephanus Phillipsi, Roem., and Crioceras
( 5 rombecki, v. Koen.
Flere ren ie pees Strombecki, v. Koe
Crioceras capricornis, Roem.
Lower. ,, LHoplites noricus, Roem., and H. radiatus, Brug.
( » Crioceras curvicosta, v. Koen., and Ole. terscissus,
Uoner v. Koen. 3
ge » Ole. psilostomus, Neum. & Uhlig, and Saynoceras
rrecosum, D’ Orb
WASSER. verrUcoswin, : :
: . », Ole. Keyserlingi, Neum. & Uhlig, and Ole. Brancoi,
Neum. & Uhlig.
Lower. S
»» Oxynoticeras Gevrili, D’Orb.,and O. heteropleurum,
Neum. & Uhlig.
SS a
BERRIASIEN = Wealden.
More than two hundred species are described, and nearly all of
them figured in an admirable manner in the fifty-five plates accom-
panying the work. The species are grouped in about twenty genera,
Reviews—Greological Survey of England and Wales. 269
of which the more numerously represented are Hoplites, Crioceras,
Ancyloceras, and Neumayr’s Olcostephanus (or Holcostephanus), with
its subdivisions Craspedites, Polyptychites, Astieria, and Simbirskites,
proposed by Professor Pavlov, the author following the late Professor
Hyatt in regarding Pavlov’s divisions as of generic importance. A
very large proportion of the species are new; but there are no new
genera.
For this valuable contribution to our knowledge of the fauna of
these beds in North Germany, Professor v. Koenen deserves the
hearty thanks of all, and especially of those who are more particularly
interested either in the Lower Cretaceous rocks as a whole or in
their Cephalopod fauna, and we are sure that many will look
forward with eagerness to the appearance of the second part of
this excellent monograph.
I].—Memoirs or THE GeroLogicaAL SuRvVEY oF ENGLAND AND
WALES.
T is again our pleasant task to call attention to the work of the
Geological Survey, and to offer our congratulations to the
Director, Mr. J. J. H. Teall, F.R.S., and to the Board of Agriculture,
under whose auspices the publications of the Survey Memoirs now
appear, upon the excellent series recently presented to the public.
1.—The Geology of the South Wales Coalfield. Part III: The
country around Cardiff, being an account of the region comprised
in Sheet 263 of the Map. By Ausrey Srranay, M.A., F.GS.,
and T. C. Canrrity, B.Sc. 8vo; pp. vi and 148, with 13 text
figures. (London: KH. Stanford (or of Messrs. Dulau & Co., 37,
Soho Square, W.), 1902. In paper wrapper, price 2s. 3d.)
The district of the South Wales Coalfield is one with which
Mr. Strahan is specially acquainted, and this third memoir upon it
forms the explanation to Sheet-map No. 263. The area was originally
surveyed, about the year 1840, by Sir H. T. De la Beche, with
the assistance of Mr. W. T. Aveline,’ but additions, chiefly in the
Secondary rocks, were made in 1872 by H. W. Bristow and
H. B. Woodward. The re-survey on the six-inch scale was carried out
during the years 1892-6, under the superintendence of Mr. Strahan,
the author of this memoir, who himself surveyed the greater part of
the sheet, while Mr. Cantrill was engaged upon the western part,
and has supplied the descriptions of the area surveyed by himself.
The oldest strata, consisting of Ludlow and Wenlock rocks, come
to the surface near Cardiff in the axis of a great anticline of pre-
Triassic age. Their existence was first detected by the Rev. Norman
Glass in 1861, but it was not until 1879 that their extent and
age were placed beyond doubt by Professor W. J. Sollas. Much
information concerning them was obtained at a later date also by
Mr. John Storrie.
The Old Red Sandstone presents the same general features as in
1 An obituary notice of this veteran geologist will be found on pp. 285-286 of the
present Magazine.
270 Reviews—Geological Survey of England and Wales.
Monmouthshire, and the precise position of the boundary between
the Upper and Lower Old Red Sandstone still remains doubtful.
The Carboniferous Limestone is concealed for the most part by
later rocks, but is evidently far thicker on the southern than on the
northern side of the coalfield, as is the case with all the subdivisions
of the Carboniferous system.
Among the most interesting features of the geology is the partial
uncovering of a pre-Triassic landscape by the denudation of the
Trias and Lias from parts of the platform of Palzeozoic rocks upon
which they were deposited. Nota few old headlands and islands
have thus been brought to light, and some are even playing the same
part in the present seascape which they played in Triassic times.
All these facts received full recognition from De la Beche.
In the examination of the Rheetic and Liassic beds the surveyors
have availed themselves of the detailed work of H. W. Bristow,
R. Etheridge, and H. B. Woodward, and of the additions made to it
by Mr. John Storrie and Mr. F. T. Howard.
Superficial geology is well illustrated in the neighbourhood
described in this memoir. The raised beach so well known round
the shores of the Bristol Channel exists near Weston-super-Mare,
and the suggestive observation of Mr. H. C. H. Day as to the age of
the bones contained in it have received confirmation from recent
observations in Gower, where the beach and its associated ‘head ’
are seen to be of earlier date than the local glacial drift. Recent
work on the glacial deposits confirms Professor Edgeworth David's
conclusions made in 1883.
Post-glacial deposits were admirably displayed in the excavations
at the Barry Docks, where conclusive evidence was obtained of
a subsidence of the land of upwards of 50 feet during and since
Neolithic times. In this investigation also Mr. Storrie gave valuable
assistance.
The Map is issued in two editions. On the edition for Solid
Geology the Glacial Drift is omitted, while on the Drift edition the
areas occupied by Drift are coloured, as well as those portions of solid
geology which are not concealed by the Drift. Manuscript six-inch
maps, geologically coloured, are deposited in the Office, where they
can be consulted. Copies of these maps can be obtained at cost price.
It is much to be regretted that a geologically coloured map is not,
as a rule, issued with every Survey Memoir.
The figures given in the text leave much to be desired (see p. 58).
Surely clearer figures and better printing ought to be insisted upon
from the King’s Printers at the present day.
The memoir is accompanied by an excellent index.
2.—Index to Report on the Geology of Cornwall, Devon, and
Somerset, by Sir Hunry T. Dz ta Becue, C.B., F.R.S. Index
compiled by Cuement Rerp, F.R.S. pp. 34. Printed for
H.M. Stationery Office. (London: E. Stanford (or of Messrs.
Dulau & Co., 37, Soho Square, W.), 1903. Price 1s.)
The Geological Survey have done good service to science in
printing this Index to De la Beche’s “ Report” on the Geology of
Reviews—Geological Survey of England and Wales. 271
Cornwall, Devon, and West Somerset, most carefully compiled by
Mr. Clement Reid, F.R.S. Notwithstanding the fact that De la
Beche’s “ Report” was published in 1839, it was destitute of an
index. No less than 1,500 copies were issued, and the memoir
is now out of print. It has, however, become one of the classics
of geology, and being a permanent work of reference an index has
been a great desideratum, which is now supplied by Mr. Clement
Reid, and should be bound up with every existing copy of this
valuable memoir.
Copies of this Index may be obtained from any agent for the sale
of Ordnance Survey maps, or through any bookseller, from the
Ordnance Survey Office, Southampton.
3.—The Geology of the Isle of Man. By G. W. Lamptueu, F.G.S.
With Petrological Notes, by Professor W. W. Warts, M.A.,
F.G.8. 8vo; pp. xiv and 620, with a geologically coioured
map. Printed for H.M. Stationery Office. (London: H. Stanford
(or of Messrs. Dulau & Co., 37, Soho Square, W.), 1908. Bound
in cloth, price 12s.)
It is not often that one geological surveyor has the pleasure and
satisfaction of seeing his name recorded as having completed a
memoir entirely by himself. Prof. J. W. Judd had the honour,
when on the Survey many years ago, to survey a whole English
county, that of Rutland; but Mr. Lamplugh has surveyed a whole
island; nay, more, for was not Man a kingdom in itself up to 1765,
when the heiress of the Duke of Athol ceded her rights as Lord of
Man to the Crown; but it still has its own Parliament (the House
of Keys). Rising in the middle of the Irish Sea (with a length of
34 miles and a breadth of from 10 to 12 miles), it has an area,
including ‘the Calf’ off its south-western extremity, of 227 square
miles (145,325 acres), of which 170 square miles, or three-fourths
of the whole island, are occupied by slate and greywacke rocks,
probably of Upper Cambrian age, composing the hilly massif.
Strata of Lower Carboniferous age occur in a small basin of 7 or 8
square miles at a low elevation in the south of the island; and a
narrow strip of red sandstone, probably belonging to the same
period, borders the coast for 2 miles about midway upon the western
side. The northern extremity consists of a low-lying tract of about
45 square miles, which is an addition made to the Island in Glacial
times by the deposition of great masses of glacial drift upon the
pre-Glacial sea-floor. Deep borings through this drift have recently
revealed a rock floor of Triassic, Permian, and Lower Carboniferous
strata at a considerable depth below sea-level.
The following table of strata shows the divisions which have been
adopted for the one-inch map of the Geological Survey, published
in 1898. The more southerly portion of the northern drift plain
may possibly be underlain by rocks intermediate in age between the
Manx Slate Series (Upper Cambrian ?), which bounds it on the
south, and the Lower Carboniferous strata, which have been proved
in the borings at its northern margin. No divisions have been
272 Reviews—Geological Survey o, England and Wales.
introduced which have not been actually proved to exist within
the area.
TABLE OF STRATA FOR THE IsLE or Man.
Blown sand.
Peat. : J
Ala ears i Fresh-water.
\ Raised Beach. Marine.
Late Glacial Flood-Gravels.
Sand and Gravel occurring as platforms.
Sand and Gravel occurring as mounds.
Boulder-clay or Loam, and Rubble Drift.
Great Unconformability .
Red Marls (saliferous). Proved in deep borings beneath
INSHASISS 203 90> oa: { St. Bees Sandstone. the drift-plain at the northern
Permian... ...... Lower Marlsand Brockram. j end of the island.
Great Unconformability.
Carboniferous Limestone Series.
Basement Sandstone and Conglomerate.
Great Unconformability.
RECENT ...
(CABACIN S55 oan) ond
CARBONIFEROUS .. {
Barrule Slates.
“6 eect locall ‘ Crush Conglomerate.’
Upper Camprian? Manx Slate Series { divided te Agneash an other Grits.
\ Lonan and Niarbyl Flags.
CoNTEMPORANEOUS.
; ‘ Tutt Agelomerate, etc
Carboniferous... 55 di ehsihe
Basalt.
Manx Slate Series. Tuff (small patches near Dalby only).
Intrusive.
Olivine Dolerite (Tertiary ?) dykes.
Iexrous Rocks ...4 Diabase, ete. (‘Greenstone ’) dykes.
Diabase, Epidiorite, Chloriteschist, etc. (‘Altered Greenstone’),
dykes.
Diorite and Camptonite dykes.
Mica-trap dykes.
Microgranite dykes.
Granite.
The geological maps of the island, of which Mr. Lamplugh’s.
memoir contains a very full and admirable description, are issued in
two editions, one with and the other without the Drift.
Besides the chapters of topographical details regarding the rocks
of the island which are arranged to serve as a geological guidebook
to those in search of local information, the work contains general
chapters in which a broader method of treatment is adopted and
prominence is given to the phenomena of more than local interest.
Thus, the descriptions of the physical features of the isiand, of the
‘Crush Conglomerate’ and other curious rock structures and types
of folding produced by earth-movement in the Manx Slates, of the
disturbance of a different character exhibited by the Carboniferous
rocks, of the structure of the Irish Sea basin as revealed by deep
borings in the north of the island, and of the condition of the
island during the successive stages of the Glacial Period,—all contain
matter of wide geological interest. The chapters on the petrography
of the great variety of most interesting igneous rocks and of those
of sedimentary origin have been prepared by Professor W. W. Watts.
Reviews—Geological Survey of Scotland. 273
Under the heading of Economic Geology there will be found
a general account of the rich metalliferous veins for which the
island is noted, and a careful description of the very numerous
mine workings and trials that have been carried out in exploiting or
testing these veins. The book is illustrated by very numerous plates,
figures, and sections. 7
We congratulate the author upon this very excellent and well-
prepared volume. But greater attention should be given by the
printers to the reproduction of the illustrations in the text, which
still leave much to be desired. The collotype plates are admirable,
and mark a distinct advance in the publications of the Geological
Survey.
TIJ].—Memorrs or tHE GEOLOGICAL SURVEY OF SCOTLAND.
1.—The Geology of Lower Strathspey (Explanation of Sheet 85).
By L. W. Hiyxman, B.A., F.R.S.E., and J. Grant Witson ;
with Petrological Chapter and Notes by J. 8S. Fierr, M.A., M.B.,
C.M., D.Sc. 8vo; pp. vi and 92, with 3 plates and 3 text figures.
(Printed for H.M. Stationery Office by James Hedderwick &
Sons, Glasgow. J. Menzies & Co., Edinburgh (or of Messrs.
Dulau & Co., 387, Soho Square, London, W.), 1902. Price
Is. 6d.)
HIS memoir describes the geology of Lower Strathspey, a
district embracing 432 square miles in the counties of Hlgin
and Banff. Special attention is given to the development of the
topographical features of the region. The metamorphic and igneous
rocks are described, and a section is devoted to the petrography of
the area by Dr. J. S. Flett. In connection with the Old Red
Sandstone of Lower Strathspey, reports are given in the Appendix
by Dr. R. H. Traquair, F.R.S., ““On the Fishes of the Old Red
Sandstone,” and Mr. R. Kidston, F.R.S., on the fossil plants of the
Old Red Sandstone of Scotland. The glacial deposits and economic
products are described. The three process plates are excellent.
A bibliography is given, and an index completes the work, but
the geological map (Sheet 85) does not accompany the memoir.
2.—The Geology of Eastern Fife: being a description of Sheet 41
and part of Sheets 40, 48, and 49 of the Geological Map. By
Sir ArcurpatD Guinin, D.C.L., F.R.S.; with an Appendix of
Fossils by B. N. Peacu, F.R.S. 8vo; pp. xvi and 422, with
12 plates and a geologically coloured map and 71 figures in the
text. (Printed for H.M. Stationery Office by James Hedderwick
and Sons, Glasgow. J. Menzies & Co., Edinburgh (or of Messrs.
Dulau & Co., 37, Soho Square, London, W.), 1902. Bound in
cloth boards; price 8s.)
The memoir (like that by Mr. Lamplugh on the Isle of Man)
is quite up to date, being issued bound in cloth, and accompanied
by 12 plates and a geologically coloured map of EHastern Fife,
besides numerous figures in the text. It is a district long since
DECADE IV.—VOL. X.—WNO. VI. 18
274 Reviews— Geological Survey of Scotland.
explored by the Geological Survey for Scotland; and when its
author, Sir Archibald Geikie (the late Director of the Survey), was
quite a young man (engaged in planting the laurels which he now
so gracefully wears) he wrote an admirable article on Old Volcanic
Action at Burntisland (Fife) on the north shore of the Firth of
Forth, and described a volcanic bomb he had observed in Carboni-
ferous beds at King’s Craig in 1862 (see Guon. Mac., Vol. I, 1864,
pp. 22-26). : :
The district described in this volume comprises that portion of
the county of Fife which lies to the east of a north and south line
drawn from the mouth of the River Leven on the Firth of Forth to
Wormit Bay.on the Firth of Tay. It completes the description
of the geology of Fife, of which the first part, comprising the
central and western divisions of the county, was published at the
close of the year 1900. The account here given of the general
geological structure of the ground and the distribution of the rocks
has been based partly on the original field-maps just referred to and
partly on copious detailed notes made by the author during repeated
traverses of the ground. Having in earlier years had frequent
opportunities of visiting the east of Fife, he had become familiar
with its geology. But for the preparation of this memoir
Sir A. Geikie spent a portion of the Spring of 1900 in examining
many of the more important sections, aud he also devoted the
Summer and a portion of the Autumn of 1901 to the same purpose.
The unique feature in the geological history of this part of Central
Scotland is presented by the series of some 80 volcanic vents
distributed in a band, which crosses the peninsula from Largo to
St. Andrew’s Bay. Many years ago the author called attention
to the nature and interest of these vents, and pointed out how
important is the evidence which they furnish as to the internal
structure of volcanoes. But up to the present time no complete and
detailed account of the whole series of them has ever been published.
He has accordingly made a renewed study of the subject, and
has devoted four chapters to a full presentation of the facts and
a discussion of their bearing on the history of volcanic action in this
country.
The author acknowledges his great indebtedness to the late
Mr. J. W. Kirkby for valuable assistance given him in preparing his
account of the Carboniferous formation of the Hast of Fife. He
generously supplied detailed tables of the coast-sections and careful
manuscript notes (both paleontological and stratigraphical), which
will be found embodied and indicated in this volume. No such
careful and detailed work has been made of any part of the Carboni-
ferous system of the British Islands as that carried out by Mr. Kirkby
on the shores of Fife.
Mr. C. D. Geddes, mining engineer of Edinburgh, has furnished
the author with records of all recent borings in Hast Fife in search
of coal; but of late years little has been done to develop the
mineral fields of the district, so that the maps remain much the same
as when surveyed 40 years ago by Mr. H. H. Howell.
Reviews—Geological Survey of Ireland. 275
In the Appendix Mr. B. N. Peach, F.R.S., Mr. C. B. Crampton, and
Mr. D. Tait furnish a general list of all the fossils obtained in Hastern
Fife; assisted by Dr. R. H. Traquair, F.R.S., for the Fishes ;
Dr. Wheelton Hind for the Mollusca, ete.; Mr. R. Kidston, F.R.S., for
the fossil Plants; Prof. T. Rupert Jones, F.R.S., and the late Mr. J. W.
Kirkby for the Entomostraca, ete. These are arranged in strati-
graphical groups, in botanical and zoological grade, and the localities
are all given by means of numbers. Special lists of fossils are also
added. The series of 12 plates are devoted mostly to volcanic and
glacial phenomena, which the coast of Hast Fife admirably illustrates.
We are glad to see the historic ‘ Rock and Spindle’ still stands on
the beach two miles east of St. Andrew’s. This might, with advantage,
have been reproduced on a larger scale, so as to bring out more
effectively its remarkable features. Dr. J.S. Flett and Mr. H. J.
Seymour contribute a chapter on the petrography of some-of the
rocks of Eastern Fife, and one recognises many effective sketches of
geological phenomena from the notebook of Sir A. Geikie, reproduced
as process cuts in the text. Certainly the King’s printers in Scotland
do their work better than those for England, and unless our London
printers look carefully to their laurels the memoirs of the Survey are
apt to be sent ‘over the border’ for production.
TV.—Tue Gerouogicat Survey oF IRELAND.
The Geology of the: Country around Dublin (Explanation of
Sheet 112). By G. W. Lamptuau, F.G.S., J. R. Kitron,
A. M‘Henry, M.R.I.A., H. J. Seymour, B.A., F.G.S., and
W. B. Wrieut, B.A. 8vo; pp. viii and 160, with 5 plates and
21 process illustrations in the text, and a coloured geological
map (Sheet 112). (Printed for H.M. Stationery Office by Alex.
Thom & Co., Limited, Dublin. Sold by Hodges, Figgis, & Co.,
Limited, 104, Grafton Street, Dublin (or of Dulau & Co., 87, Soho
Square, London, W.), 1903. Price 3s.; price of Map 1s. 6d.)
[In part reprinted from the explanatory Memoir to accompany Sheets 102 and
112, by J. Beete Jukes, M.A., F.R.S., and G. V. Du Noyer, 1861; revised 1875.]
This memoir has been prepared to accompany and explain the
new colour-printed drift-map of Dublin and its environs. The
description of the ‘solid’ rocks is mainly reprinted from the original
“Memoir to accompany Sheets 102 and 112,” which has long been
out of print, but this part has been expanded to include a summary
of the researches carried out by private workers and by the Survey
since that memoir was published, and a newly written portion
dealing with the ‘ petrography ’ of these rocks has also been added.
The description of the glacial drifts and other superficial deposits
is altogether new, and contains the information collected during the
survey of these deposits in the year 1901. The material under the
heading of ‘Economic Geology’ has been greatly enlarged from
the previous memoir, and now includes a list of the minerals of the
district and an account of researches into the character of its soils.
276 Reviews—Greological Survey of Ireland.
The previous geological literature of the neighbourhood is also for
the first time discussed, under the heading of ‘ Bibliography,’ and
a list of this literature is given in an appendix. The memoir is
illustrated by 5 plates from photographs, by R. Welch, of Belfast,
and by 21 figures in the text.
The district included in this sheet lies wholly within the county of
Dublin. The city of Dublin is in the centre of the sheet, and its
suburbs extend along the shores of Dublin Bay to Dalkey on the
south and Dollymount on the north, and also along the Liffey valley
westward to Chapelizod. The watering-places of Howth and Killiney
lie respectively north and south of Dublin Bay within the sheet, and
the islet of Ireland’s Hye occurs within its northern margin.
The southern part of the district is high mountainous ground,
rising up to 1,763 feet above the sea at a point called Fairy Castle.
There is another summit called Tibradden Mountain, which is
1,540 feet; and the better known Three Rock Mountain, everywhere
visible from the neighbourhood of Dublin, is 1,479 feet high. A hill
called Slieve na bawnoge at the extreme south-west corner is
1,265 feet. Of the lower hills, Killing Hill has a height of 512 feet,
while the summit of that of Dalkey is 472 feet high, within a quarter
of a mile of the sea. The mountains, like all granite mountains,
have heavy-looking, gently sweeping summit outlines, their flanks
descending gradually but rather steeply on the east towards the sea,
and on the north to the plain traversed by the Dodder and the Liffey.
This plain spreads northwards from the foot of the hills, with
gentle undulations of between 100 and 200 feet above the sea, rarely
rising above the greater height, and often, especially near the sea or
on the margin of brooks and rivers, falling below the lesser altitude.
It forms a portion of the central plain of Ireland. In the north-
western part of the map, however, north of Finglas, the land rises
to a height exceeding 300 feet, and the rocky promontory of Howth
has a summit of 560 feet in height. All the north-flowing drainage
of the southern hill range is received by the River Dodder, which
Swerves eastward across the plain to the mouth of the Liffey, after
issuing from the mountains through the deep hollow of Glenasmole,
a little south of Tallaght. The eastern portion of the range is drained
principally by two small streams which flow eastward into Killiney
Bay. The Liffey, which has a level of less than 40 feet where it
enters the district, brings the drainage from the plains of Kildare
into the head of Dublin Bay, into which also runs the lesser river
Tolka, with a course parallel to the Liffey, and only one to two miles
further north.
The solid rocks of the district are shaly and massive Carboniferous
Limestones, Lower Limestone shales and fine grits, Lower Silurian,
Bala, and Llandeilo beds, altered Silurian grits and shales, Cambrian
quartz rock, granite and basaltic andesites.
The memoir deals with (1) the solid geology; (2) the
palzontology ; (3) the petrography ; (4) the relation between
the external form of the ground and its internal structure, and
hereunder to the consideration of Glacial and post-Glacial deposits
Reviews—LEgyptian Geology. Qte
and their origin; (5) the detailed description of the solid rocks;
(6) the detailed description of the drifts.
Then we come to the section Hconomic Geology—to the subject of
mineral lodes, building materials, water supply, and agricultural
geology. :
Treated economically, the drifts are composed of blown-sand
(forming sandy hillocks), recent intake (forming silt and made
ground), alluvium, silty and loamy river-flats, peat and peaty-
deposits. Raised beaches, pebbly sandy flats, river-gravel terraces
(these are usually from 1 to 3 feet of loam on gravel). Late Glacial
flood-gravel (forming stony loam on gravel tending to be water-
logged). Sands and gravels of mounds and Hskers (forming dry
stony loam on gravel, usually full of limestone), Sand and gravel
intercalated in Boulder-clay (forming soil nearly like that of Boulder-
clay). Boulder-clay containing much limestone (forming clayey
loam with stones). Clayey drift mainly of non-calcareous material,
including later hill-wash (forming a light, stony soil, varying with
character of subjacent rock).
The five plates are admirably reproduced and well printed. There
are also 21 sections and illustrations in the text, including a figure of
Oldhamia, which is a very old friend indeed. The memoir will prove
avery useful addition to the series of Geological Survey publications.
V.—EHeyptian GEOLOGY.
Survey Department, Public Works Ministry [Egypt]. Geological
Survey Report. Topography and Geology of the Eastern Desert
of Egypt, central portion, by T. Barron and W. F. Hume.
8vo; pp. xii, 332, with maps, plates, and sections. (Cairo,
1902 [so dated, but issued May, 1903]. Price 400 milliemes
(8s. 4d.).)
N this Report, which has been expected for many months, the
excellent arrangement of previous reports is followed of first
giving a complete topographical survey of the region to be
geologically surveyed. This brings together a great deal of useful
material relating to Egyptology, meteorology, botany, and zoology,
of considerable value when dealing with a new area, the features
of the country being illustrated by aseries of beautiful photogravures
of striking scenery and points of geological interest.
The geology is the result of an examination by two parties of the
staff during 1897-98, aud the succession of beds dealt with includes
Pleistocene, Pliocene, Miocene, Hocene, Cretaceous, all resting on
volcanic and metamorphic rocks. The whole of the volcanic and
metamorphic beds (with the exception of a few noted in the text)
have been planed down by marine erosion, and the Nubian
Sandstone has been laid down on the smoothed surfaces. This
Nubian Sandstone is considered by the authors to be of Santonian
age (Upper Cretaceous), there being no proof of beds older than
that period in the district. The Cretaceous limestones overlying
the Nubian Sandstone are mainly Middle Senonian (Campanian).
278 Reviews—G. F. Matthew—Cambrian Faunas.
There is a marked unconformity between these strata and the over-
lying Hocene shales and limestones, which consist of two divisions,
the Serrai limestones and the Esna shales, respectively of Londiniam
and Suessonian age. Andesites have been intruded into these beds,
which are succeeded by Pliocene rocks, Oligocene being absent, and
Miocene beds occurring only in the extreme north-east of the area.
The Red Sea is considered to have come into existence in late Pliocene
times, as the highest coral reefs (200 metres above sea-level),
contain a possible mixture of Pliocene and Pleistocene corals. The
youngest coral reefs are associated with gravels and conglomerates
which must be of Pleistocene age.
Special chapters are devoted to Economics, which include gold
and petroleum, and an interesting discussion is raised on the
“Influences giving rise to the Hastern Desert structure.” These
influences may be summed up as follows: — (1) Its geological
structure; (2) tectonic movements, folding and faulting, breaking
up the plateau into isolated areas; (3) water; (4) insolation and
changes of temperature; (5) mineral composition of the rocks and
differences of their coefficients of expansion; (6) the dykes, as
strong determinative factors in the hill sculpture; (7) wind, only
effective where it has a supply of sand and plenty of space to act ;
(8) Nubian sandstone, and not granite, is the source of the sand ;
(9) sand action, in eating away the limestones along previously
formed cracks.
The general get-up of the volume is highly satisfactory, the
printing of the text, maps, and sections, which has all been done in
Cairo, is excellent, the photogravures are by Albert, of Munich, and
there is a singular absence of misprints. There is a voluminous
index and a good bibliography, both quite indispensable to such
a report. We would, however, ask the Director to insert the word
“ Kgypt” after the word “ Ministry ” in the covers and title-pages
of these reports, and to believe that the future difficulties which will
arise from a book dated 1902, but not issued till 1908, are more
real than at first sight appears. We are grateful for the list of
publications which appears on the back of the cover, for in an
unnumbered series of publications one is never certain how
complete or incomplete one’s set may be. C. D.S.
VI.—Norrs on Camprian Faunas. By G. F. Martruew, LL.D.
with description of a new species of Metoptoma. (Trans. Roy-
Soc. Canada, series 11, vol. viii, sec. iv, p. 93.) 1903. -
shee article deals with several subjects relating to the Cambrian
faunas of Canada. In the first note the differences in musculation,
circulatory system, etc., of the Oboloid shells of the Cambrian in
Canada are described. It is claimed that these shells belong to
several subgenera. All but one are older than the type of the genus,
Obolus Apollonis.
In the second note the enlargement during Cambrian time of the
shells of several genera of Cambrian Inarticulate Brachiopoda is
shown to have taken place.
Reports and Proceedings—Geological Society of London. 279
In the third note proofs are shown that favour the view that the
Upper Etcheminian fauna (Basal Cambrian) invaded Hastern Canada
from the south-west.
In connection with the fourth note, in which the Brachiopodous
shells of the Cambrian fauna of Mt. Stephen in British Columbia are
dealt with, is the description of a new species of Metoptoma-
IANS OuSwyS| JAIS7ID) 1S sS4~OO UDA AON ErS
GeotocicaL Sociery or Lonpon.
I. — April 29th, 1903. — J. J. H. Teall, Esq, M.A, F.RBS.,
Vice-President, in the Chair.
Prof. Bonney, in exhibiting three specimens found by Prof. Collie,
F.R.S., on Desolation Valley Glacier, east of the watershed of the
Rocky Mountains and a little south of the Canadian Pacific Railway,
pointed out that one, a slab of white quartzite, was covered by
horizontal worm-burrows, often about one-third of an inch in
diameter, such as those named Planolites by Nicholson; another, of
the same material, had blunt ridges, tapering to a point, an inch or
so long, rudely parallel, in sets of about four. These he should
have taken for the tracks of a (?) Crustacean, but they were single,
not paired, and without any sign of a medial furrow. The third
was a Slab, measuring about 11 by 5 inches and 13 inches thick, of a
brownish quartzite, passing quickly on one side into a green argillite,
the other side being thickly studded with dome-like eminences about
an inch in diameter and nearly half this in height. Most of them
show a slight ‘dimple’ at the top, and a very slight ‘step’ or
swelling often forms a sort of ring part way up the dome. Some
argillite, like that on the other side, remains about their bases, and
a few tracks of Planolites wind among them, and once or twice seem
to pass over them. The domes are formed of a quartzite, identical
with that of the slab. It shows a very faint stratification, and
consists of grains of quartz, not seldom well rounded, embedded in
a minutely micaceous matrix, probably an alteration product of
felspar. They cannot be concretions; so the speaker regarded them
as the casts of pits in the argillite, made by a large annelid, which
retreated into it vertically (? Scolithus), afterwards filled up by a
layer of sand.
The following communications were read :—
1. “The Age of the principal Lake-Basins between the Jura and
the Alps.” By Charles 8. Du Riche Preller, M.A., Ph.D., A.M.I.C.E.,
M.1.E.E., F.R.S.E., F.G.S.
(1) In a paper read before the Society last session, the author
showed, on the evidence of extensive high-level deposits of Decken-
schotter in Subalpine France and Switzerland, that the principal
Swiss lake-basins could not have existed at the time when those
deposits were formed, during and after the first or Pliocene glaciation
of the Alps. In the present paper he deals with the question reserved
in the preceding one, that is, to which subsequent period the forma-
tion of those lake-basins should be assigned. By the light of further
280 Reports and Proceedings—Geological Society of London.
recent investigations in the different localities, he first considers
the conditions of the Zurich lake-valley, where the successive
glacial and fluviatile deposits are clearly defined, and then applies
his conclusions to the other principal lake-basins lying in the same
zone along the edge of the Alps.
(2) The hitherto generally accepted view that the lake-basins are
pre-Glacial in the old sense, or were formed during the first inter-
Glacial period, rests, in the main, on two arguments: (1) that the
alluvia at the lower ends of the lakes are all Glacial, not only from
their appearance, but because the materials composing them could
only have been transported thence by glaciers, which either passed
over the lakes by bridging them, or through them by completely
filling them with ice; and (2) that the zonal bending of the Molasse
along the edge of the Alps, to which the lake-basins owe their
existence, occurred before the second or maximum glaciation,
because at a point in the Lorze ravine (near the Lake of Zug) the
Deckenschotter conglomerate dips reversely, that is, up the valley,
while the overlying, younger, loose gravel dips in the opposite
direction.
(3) The author adduces evidence to show that the deep-level
gravel-beds in the Limmat Valley near and below Zurich are essen-
tially fluviatile, composed of the characteristic Alpine material
of the Rhine and Linth drainage areas, and in all other respects
similar to the gravel carried by the River Sihl at the present day.
These gravel-beds rest upon Glacial clay of the second glaciation,
which fills the Molasse-bed of the valley to a great depth, and are
overlain by the moraine-bars and secondary products of the third
glaciation, the latter being overlain by and mixed with the
post-Glacial alluvia of the Sihl.
(4) He further argues that it is, on mechanical grounds, difficult
to conceive how glaciers could either bridge, or completely fill with
ice, such extensive basins as those of the principal Alpine lakes, from
2 to 8 miles in width and from 470 to 1,020 feet in depth, the
quantity of water to be displaced and expelled in the individual
cases ranging from 38,500 million to 90,000 million cubic metres
or tons.
(5) As regards the more recently enunciated argument of the
Deckenschotter and overlying gravel exposure in the Lorze
Valley, the author points out that, apart from the difficulty of
differentiating the second and third glaciation materials in that
locality, it is obviously hazardous to deduce from a purely local
phenomenon of this kind, and more especially from any dip of loose
gravel—in contrast with rock or compact conglomerate—the date of
the zonal bending affecting six valley systems, and extending over
more than 200 miles along the edge of the Alps.
(6) The author’s investigations point to the conclusion that the
deep-level Limmat gravel-beds, overlain by the moraine-bars of
the third glaciation, were deposited by a river during the second
inter-Glacial period; that the lowering of the valley floor was
initiated in the course of the third glaciation, probably when the
Reports and Proceedings—Geological Society of London, 281
glacier had already reached its maximum extension, about 10 miles
below Zurich; that the zonal subsidence continued throughout the
retreat of the ice; and that the simultaneous formation of the lake-
basin should therefore be assigned to the end of the Glacial Period,
after which the original basin was, notably at its upper end,
restricted to its present dimensions by post-Glacial alluvias—
(7) In conclusion, the author shows that the same arguments
apply, in the main, also to the origin and age of the other principal
zonal lake-basins, which he illustrates by longitudinal sections. In
his view, the position and depth of these basins, as well as the
intervening ground, point to the probability that the bending took
place not only along one line, but along several, more or less
parallel, not always continuous lines within the zone between the Alps
and the Jura; that the bending was by no means of uniform depth ;
and that, therefore, the Alps did not subside as a rigid mass, but
that the zonal bending along their edge merely extended locaily for
some distance from the deepest points of the lake-basins along the
floors of the principal Alpine river valleys.
2. “On a Shelly Boulder-Clay in the so-called Palagonite
Formation of Iceland.” By Helgi Pjetursson, Cand. Sci. Nat.
(Communicated by Prof. W. W. Watts, M.A., M.Sc., Sec. G.S.)
There is no equivalent in the Tertiary basalt plateaux of Britain
of the great palagonite formation of Iceland, which Prof. Thoroddsen
has shown to be younger than the basalt formation of the latter
island. The basement layer of the breccia formation, resting
directly upon the basalts, contains glaciated blocks of all sizes, up to
6 feet and more in diameter. ‘These ground-moraines are followed
by tufaceous sandstones, conglomerate, columnar basalts, other
ground-moraines, and volcanic tuffs and breccias. At Birlandshofdi
a shelly Boulder-clay, 70 to 80 feet thick, rests upon the fundamental
basalt, which here shows a glaciated surface. Unbroken shells are
very rare. Astarte borealis is the most common shell, and Saxicava
arctica and Mya truncata are less common, indicating that some of
the older moraines are of Pleistocene age. The author concludes
that volcanic activity did not pause in Iceland during the Glacial
Period, but that it was especially active at the beginning and the
close of glaciation, building up bulky hills of slags and ashes, some
of which have survived the Glacial Period as volcanoes, while others
have become extinct. Volcanic activity had died out in Britain at
this time, and hence the palagonite formation is unrepresented in
that country.
I.—May 18th, 1903.—Edwin Tulley Newton, Esq., F.R.S., Vice-
President, in the Chair. The following communications were
read :—
1. “On some Disturbances in the Chalk near Royston (Hertford-
shire).” By Horace Bolingbroke Woodward, Hsq., F.R.S., F.G.S.
A ‘line of flexure’ is marked on the Geological Survey map from
Therfield, south-west of Royston, in Hertfordshire, to near Heydon
282 Reports and Proceedings—Geological Society of London.
in Cambridgeshire, a curved line a little below the crest of the
Upper Chalk escarpment. The author in 1902 found evidence
which satisfied him that the disturbances, previously supposed to be
an anticline, were due to glacial action, a view confirmed during
the present year. Four sections are described: Great Chishall,
Pinner’s Cross, the Limekiln south-west of Newsell’s Park and north
of Barkway, and north of Reed. The disturbed Chalk near Royston,
with its fractured and displaced flints, occurs in conjunction with
Boulder-clay, and the latter is found beneath a considerable thick-
ness of disturbed Chalk. This is compared with similar phenomena
near Trimingham, and at Litcham in Western Norfolk. While
Boulder-clay occurs along the high ground bounding the disturbed
area to the south, the vale and undulating downs immediately to
the north are devoid of this Glacial Drift. The facts were to be
explained, on the land-ice theory, if the ice were at first welded to
the rubbly surface strata in regions north of the escarpment, and,
when movement set in, there were overthrusts of débris-laden ice,
and upper layers of ice were rent asunder from and moved over
lower ones; while to the thrust or long-continued pressure of ice
along shear-planes at the higher levels may be attributed the belt
of disturbed strata. Certain patches of esker-like gravel in
Wardington Bottom might be explained by streams due to the
melting of the ice banked up against the scarp; and we might go
some way with Sedgwick in believing that the outlines of the
combes “do not appear to have been produced by a long-continued
and slow process of erosion; but rather to have been cleanly swept
out by rapidly descending water-floods.”
2. “On a Section at Cowley, near Cheltenham, and its bearing
upon the Interpretation of the Bajocian Denudation.” By Linsdall
Richardson, Esq., F.G.S.
According to Mr. Buckman’s map, published in 1901, the Upper
Trigonia Grit should have been seen at this spot to rest directly,
and non-sequentially, upon the Upper Freestone, whereas obser-
vation shows the intervention of at least the Buckmani Grit, part
of which thins out from 4 inches at the north-eastern end to nothing
at the other end of the quarry, which is in the direction of the
anticlinal axis. The error is not one of fact, but of inference, and
the present evidence rectifies portions of those limits which were
drawn theoretically. A section near the “Air Balloon” Inn, on the
road from Birdlip to Cheltenham, shows the Lower Trigonia Grit
covered by Buckmani Grit and underlain by the Upper Freestone.
There is only one section where the Upper Trigonia Grit is seen
to rest directly upon the Lower Trigonia Grit, the latter being only
3 feet 2 inches thick. The causes producing the Bajocian denudation
appear to have been forces so acting as to effect a repetition of
flexure along old lines of weakness (Aalenian) ; and thus in the
Birdlip area an anticline may be again located, but the elevation was
this time much greater: indeed, the level of the Aalenian denudation
was passed by the Bajocian. Other sections near Brimpsfield and
Reports and Proceedings—Mineralogical Society. 283:
in Cranham Wood are given in connection with the location of
the anticlinal axis. The exact location of the anticlines and
synclines of the Inferior Oolite rocks in the Cotteswolds, where
sections are numerous, may afford some important working hypo-
thesis for unravelling the structure of the Vale of Gloucester, where
excavations are few. =
3. ‘“ Description of a Species of Heterastrea from the Lower Rheetic
of Gloucestershire.” By Robert F. Tomes, Hsq., F'.G.S.
The specimen described was obtained by Mr. L. Richardson from
Lower Rhetic beds at Deerhurst (Gloucestershire). It occurred
a little way above the bone-bed; it is specifically and generically
new to the Rheetic, and it displays Jurassic relationships. It differs
from the several Liassic species in the small size of the corallum and
of its calices. Remarks on some other Madreporaria from the Rhestic
and from the basement of the Lower Lias are appended. it has
always been the author’s opinion that the Sutton Stone containing
Rhetic Madreporaria should be classed as Rhatic ; indeed, he believes
that it is really Upper Rheetic; and in view of the very close affinity
of its organisms with those of the Lower Jurassic, and bearing in
mind the great importance of the Ammonite zones as a means of
classification of the Liassic deposits, he asks whether the zone of
Ammonites planorbis should not be taken as the bottom of the Lias.
T1J.—Mrineratoeicat Socrery, March 24th.—Dr. Hugo Miller,
F.R.S., President, in the chair. Dr. A. Hutchinson described
some remarkably interesting experiments which he had made on
the diathermancy of antimonite. A cleavage flake of antimonite
0-29 mm. thick and 20 sq. mm. in area, perfectly opaque to light,
was placed between cross nicols and exposed to the radiation from
a limelight. The plate was somewhat transparent to radiant heat,
and the amount transmitted was measured by Boys’ radiomicrometer.
No heat was transmitted when the planes of symmetry of the
crystal coincided with the planes of polarisation of the nicols, but
the maximum effect was produced on the radiomicrometer when
the plate was turned through 45° in its own plane. The results
so far arrived at are in harmony with the orthorhombic symmetry
attributed to antimonite. Mr. J. B. Scrivenor described the
occurrence of magnetite in the Upper Bunter Sands at Hinksford,
near Stourbridge, and of anatase in the Trias of the Midlands.
The crystals of magnetite, measuring on an average ‘067 mm., were
in cubes or octahedra. The mode of occurrence and the presence
of a single set of striations parallel to the cube edge, suggest that
they are pseudomorphous after iron pyrites. The anatase, in
crystals from -025 to ‘O6mm., is found more abundantly in
the Keuper than in the Bunter. The crystals show the forms
(111) and (001), and according to the predominance of either form
are pyramidal or tabular in habit. Many of them are attached
to leucoxene derived from ilmenite or sphene. The anatase has
been formed in sitt#, after the deposition of the sandstone, as
284 Correspondence—Arthur Rowe—A. R. Hunt.
a decomposition product of other titaniferous minerals. Professor
W. J. Lewis described a large crystal of sartorite from the
Binnenthal measuring 4” x 1” x 2”. An analysis by Mr. Jackson
gave the following result: Pb = 42:93, § = 25°32, As=531:11.
Professor Lewis also discussed some peculiar twinned crystals of
copper-pyrites and cerussite. Mr. W. B. Giles contributed notes
on Howlite and other borosilicates from the Borate mines of
California. One of these, for which the author proposes a new
name, is a white amorphous mineral resembling in appearance
pandermite; the results of two closely agreeing analyses of
material from different localities corresponded to a formula 8 Ca O .
5 B,O,.6 SiO,.6 H,O. Mr. Giles also described a tantalite from
Green Bushes, West Australia, which contained 85 per cent. of
tantalic with very little niobic acid. Mr. J. Allen Howe exhibited
‘specimens of peculiar pseudo-stalactitic growths of cellos from the
North of England.
CO mE Ss @ANFD rEGEN@ sane
THE ZONE OF WICRASTER PRACURSOR.
Str,—On pp. 51 and 54 of “The Geology of the country
around Salisbury’ (Mem. Geol. Surv., Sheet 298) the term ‘zone
of Micraster precursor’ is used. As one who is not a little interested
in the genus Micraster, and more especially perhaps in the group-
form which is known as Micraster precursor, I would crave a little
information as to the reasons which have guided the author of this
memoir in finding a new zonal title.
Possibly the use of this urchin as a name-fossil is not new, and in
that case I must plead guilty to having failed to notice the first
occasion of its use. If, on the other hand, this be the first publica-
tion in which it has been employed, it would not be unreasonable
to expect some statement concerning a fortunately rare event—
the adoption of a new name-fossil for one of the zones of the
White Chalk. ArtHuR Rowe.
1, Cectt Street, Marcare.
May 6th, 1908.
SAND-DRIFTING AND SEDIMENTATION.
Sir,—I have read Professor Blake’s papers on sedimentary deposits
with much interest. So faras I can judge, my election to the General
Committee of the British Association in 1879 was due chiefly to my
work on this subject, and especially to a paper published in 1878,
‘‘Notes on Torbay.” Such being the case I very naturally made
several attempts to elicit discussion in Section C; but at that time
geologists absolutely refused to look at the subject. In 1886 I made
a number of special experiments, but the Committee of Section C at
Birmingham not only omitted even to include my paper (‘‘ Deposition
and Denudation, etc.”) in the list for reading which was published
at that meeting, but for the first time omitted my name from the
Committee. Ultimately an influential friend remedied both defects,
and I was able to read a six minutes abstract in the subsection on
Obituary— William Talbot Aveline, F.G.S. 285
the Wednesday morning. This enabled me to get a page of abstract
into the Report. The double rebuff was too marked to be mistaken.
I found the repugnance to the subject as strong at the Geological
Society as at the British Association, and with much regret was.
forced to drop it. At the time I had a yacht, an experimental tank,
a moorland river, and a mill leat; and all the experts whose opinion
was of value were favourably disposed towards my work, including
Sir G. G. Stokes, Lord Rayleigh, Dr. Sorby, and Mr. Gwyn Jeffreys.
At the Bradford meeting, in 1900, I was interested to hear
Dr. Vaughan Cornish state publicly from the platform of Section C
that he had only tripped me up once. And that happened to be
a quotation and an ambiguously worded passage. It was a trip
more than a stumble.
I am not at all surprised at the opposition I encountered in petro-
logical work. That was simply a case of amateur methods of research
versus professorial. But the opposition to my work on the subject
for which I was elected to the General Committee, and which my
judges were scarcely qualified to condemn, I have never in the least
understood. The standing difficulty is this, that some of the most
important textbooks are misleading, and, indeed, I very really hear
anyone touch on the subject without their running foul of first
principles. In 1882 I submitted a paper to the Royal Society on
Ripple-mark. It was officially suggested to me that I had not
considered Dr. Sorby’s work. Well, Dr. Sorby had supplied me
with a sheaf of his reprints, and I did not want to appear to be
criticising his observations on ‘ripple-drift,’ when I was investigating
another cause of ripple-mark, viz. wave-action. There are three
great principles which have to be considered, viz.: (1) the drafting
of sand by rivers and currents, as studied by Dr. Sorby; (2) the
conveyance of sediment in suspension; (8) the disturbance of the
already deposited sediment by waves of different sorts; and (4) the
redistribution of this sediment by a great variety of currents.
I rejoice to see Professor Blake’s papers, as they show that geologists
are now alive to the great importance of this subject, a subject which
is illustrated by every fragment of sedimentary rock cracked under
the geologist’s hammer.
It is scarcely worth while to refer to my own writings, as they are
fragmentary and scattered almost beyond my own knowledge.
I found that if I had got hold of a really important fact, that was
just the fact which, being unorthodox, would fail to get into print.
I happened to have the monopoly of a new source of information, an
experimental tank; so my various judges were sceptical, and my
judges were all-powerful. A. R. Hunt.
@s ane OPAtke nyse
WILLIAM TALBOT AVELINE, F.G.S.
Born 1822. Diep May 12, 1903.
Tur death of W. T. Aveline, at the age of 81, has removed one
of the earliest field-geologists attached to the staff of the Geological
286 Obituary— William Talbot Aveline, F.G.S.
Survey under De la Beche. He was appointed an Assistant Geologist
in 1840, and after working for a short time in Somerset on the
Mendip Hills, he was transferred to South Wales, and surveyed
parts of Pembrokeshire. Thence he worked through other counties
into North Wales, across the borders into various portions of the
West of England, and into the Midland counties as far as Nottingham.
In 1867 Mr. Aveline was appointed District Surveyor to take
charge of the mapping of the Lake District, and he resided at
Kendal until his retirement in 1882, when he went to live at
Wrington in Somerset.
All formations, from the very oldest up to the Eocene, came from
time to time under notice, but his chief work was among the Silurian
and older rocks. Although painstaking and accurate in his mapping,
he went but little beyond the actual survey of the ground. He
entered neither into the petrology nor paleontology of the rocks;
nor was he given to writing. The maps and sections of the
Geological Survey form the chief monument of his labours; and it
was in recognition of these, that he was awarded the Murchison Medal |
in 1894 by the Council of the Geological Society. His portrait will
be found in Sir Archibald Geikie’s Memoir of Sir A. C. Ramsay (1895).
The following is a list of his published memoirs and papers :—
GzEoLoGicaL SurvEY Memorrs.
1858. ‘Geology of parts of Wiltshire and Gloucestershire.’’ (With Ramsay and
Hull
1860. <‘ Geology of part of Northamptonshire.”’
1861. ‘‘ Geology of parts of Northamptonshire and Warwickshire.”’
1861. <‘‘ Geology of the country around Nottingham.’’ 2nd ed., 1880.
1861. ‘‘ Geology of parts of Nottmghamshire and Derbyshire.’’ 2nd ed., 1879.
1863. ‘‘ Geology of part of Leicestershire.’’ (With Howell.)
1872. ‘‘ Geology of the country around Kendal, Sedbergh, Bowness, and Tebay.”’
(With Hughes.) 2nd ed., revised by Strahan, 1888.
1872. <‘‘ Geology of the neighbourhood of Kirkby Lonsdale and Kendal.’’ (With
Hughes and Tiddeman.)
1873. ‘Geology of the southern part of the Furness District in North Lancashire.”
1880. ‘Geology of parts of Nottinghamshire, Yorkshire, and Derbyshire.”’
OrnER Works.
1848. ‘‘Sketch of the Structure of parts of North and South Wales”’ (with
Ramsay): Quart. Journ. Geol. Soc., vol. iv, p. 294.
1854. ‘On the ‘ Caradoc Sandstone’ of Shropshire’’ (with Salter): ibid., vol. x,
p- 62.
1866. ‘‘ The Longmynd and its Valleys ’’ (letter): Grot. Mac., Dec. I, Vol. III,
15 A)
1869. ‘On the Relation of the Porphyry Series to the Skiddaw Slates in the Lake
District ’’ (letter): ibid., Dec. I, Vol. VI, p. 382.
1872. ‘On the Continuity and Breaks between the various Divisions of the Silurian
Strata in the Lake District’’: ibid., Dec. I, Vol. IX, p. 441.
1876. ‘‘ Absence of the Llandovery Rocks in the Lake District ’’ (letter): ibid.,
Dec. II, Vol. III, p. 282.
1876. ‘* The Silurian Rocks of the Lake District’’ (letter): ibid., p. 376.
1876. ‘‘ The Graptolitic Mudstones of the Lake District” (letter): ibid., p. 527.
1877. ‘The Magnesian Limestone and New Red Sandstone in the neighbourhood
of Nottingham’’: ibid., Dec. II, Vol. IV, p. 155.
1877. ‘The Relation of the Permian to the Trias ’”’ (letter): ibid., p. 380.
1893. ‘‘The St. Bees Sandstone’’ (letter): ibid., Dec. III, Vol. X, p. 87.
1899. ‘Geology of the country around Carlisle’’ (letter): ibid., Dec. IV, Vol. VI,
p. 336.
Miscellaneous—Mr. C. L. Griesbach, OLE, F.G.8. 287
MISCHUiGANHOVUS.
———
Me. CO. L. Griessacg, C.I.E., F.G.S., Director or tur. GroLoGICcAL
Survey oF Inp1a.
The occasion of the retirement of Mr. C. Ludolf Griesbach,
C.LH., F.G.8., ete., from the post of Director of the Geological
Survey of India, which took place on February 24th, 1903, enables
one appropriately to refer to his past services in the cause of
geological science.
Mr. C. L. Griesbach belongs to an old Hanoverian family, and
his grandfather settled in England in the time of H.M. King
George III. Most of his family were celebrated as musicians ;
one of his uncles, the Rev. W. R. Griesbach, held a church living
in Yorkshire, and was interested in geology. In his early life
Mr. Griesbach’s family resided in Austria, and as a young man he
joined the Geological Survey in Vienna, and became by that means
an excellent field geologist and paleontologist. He was also an
accomplished artist. In 1869 he was chosen to join a German
expedition to explore the then but little known region of Portuguese
East Africa. After enduring with the members of the expedition
many hardships, owing to the loss of their ship, and from fever at
Delagoa Bay and on the Zambezi, Mr. Griesbach returned to Hurope.
He published in Vienna, in 1870, “‘ Geologischer Durchschnitt durch
Siid-Africa”’ (Jahrb. geol. Reichs., xx, p. 501); and in the year
following, when he came to London, a memoir “On the Geology
of Natal in South Africa” (see Quart. Journ. Geol. Soc., 1871,
vol. xxvii, pp. 53-71, pls. ii and iii, with 5 text illustrations,
a folding coloured geological map of Natal, and a double plate
of fossils).
After seven years’ residence in London, during which he was
engaged in scientific work and drawing, he was, upon the recom-
mendation of Professor Sir Richard Owen, K.C.B., and Dr. Henry
Woodward, F.R.S., appointed 26th September, 1878, by the India
Office in London, to be an Assistant Superintendent to the Geological
Survey of India, and joined in Calcutta the same year. He passed
through various grades of promotion in each year from 1880 to 1884.
From November, 1884, to October, 1886, Mr. Griesbach was
employed on the Afghan Boundary Commission, with the grade of
Deputy Superintendent, and advanced to first grade Superintendent
November, 1886. He was created a Companion of the Indian
Empire in February, 1887. From 14th January, 1888, to 22nd
July, 1889, his services were placed at the disposal of His Highness
the Amir of Kabul, made a Superintendent in June, 1889, and became
Director of the Geological Survey of India 17th July, 1894, on the
retirement of Dr. William King, F.G.S.
When resident in London, Mr. Griesbach served for some years as
an officer in the Royal London Militia, now the 6th Battalion Royal
Fusiliers, and has since been retired with the rank of Lieut.-Colonel.
During his residence in India he was employed on the following
War Services, viz. :—
288 Miscellaneous—Mr. C. L. Griesbach, CLI.E., F.G.S.
On 6th March, 1880, he was deputed on special service under the orders of the
General Commanding Southern Afghanistan; was present at the action of Girishk,
14th July, and the battle of Maiwand, 27th July; attached as Lieutenant to the
66th Regiment, Kandahar Field Force (order No. 271), dated 29th July, 1880 ;.
and was present throughout the siege of and battle of Kandahar, 1st September, 1880 ;
favourably mentioned in despatches ; received the acknowledgment of the Government
of India, also the Medal and Clasp; accompanied the Takht-i-Suliman Expedition,
1883; with the North-Eastern and Irrawaddi Columns 1891-92, Burma Medal and
Clasp ; Moranzai Expedition, 1892-3.
He was presented with a gold medal by His Majesty the Emperor of Austro-
Hungary in recognition of services rendered in connection with the carrying out of
the Scientific Expedition in 1892 to the central regions of the Himalayas.
Mr. Griesbach is alsoan F.R.G.S. ; F. As. Soc. Bengal; Foreign Corr. Geol. Soc.
Edinb. ; Corr. Memb. Verein f. Erdkunde, Leipzig ; Corr. M. Ver. f. Erdk. Berlin ;
Corr. M. k.k. geol. Reichsanst. Vienna; an Hon. Trustee of the Leipzig Museum ; and
in 1896 was elected a foreign member of the Kais. Akademie d. Wiss. in Vienna.
The following is a list of Mr. Griesbach’s scientific papers :—
1.—‘‘ Der Jura yon St. Veit be1 Wien’’: Jahrb. k.k. geol. Reichsanst., 1868,
vol. xvii, p. 123; Verh. do., 1868, p. 54.
2.—‘‘ Késsener an Jura Schichten im k.k. Thiergarten bei Wien”’: Verh. geol.
Reichs., 1868, p. 198.
3.—‘* Die Klippen im Wiener Sandst.’’: Jahrb. geol. Reichs., 1869, vol. xix,
Dee lide
4.—‘* Die Erdbeben der Jahre 1867 und 1868’’: Mittheil. der k.k. geograph.
Gesell., 1869, vol. xii, p. 195.
5.—‘“‘ Bemerkungen tiber die Altersstellung des Wiener Sandst.’’: Verh. geol.
Reichs., 1869, p. 292.
6.—‘‘ Geologischer Durchschnitt durch Std-Africa’’: Jahrb. geol. Reichs., 1870,
xx, p. 001.
7.—** Petrefacten Funde in Stid-Africa’’: Verh. geol. Reichs., 1870, p. 75.
8.—‘‘ On the Geology of Natal in South Africa’’: Quart. Journ. Geol. Soc., 1871,
XXVH, p. 53.
9.—“ Geology of the Ramkola and Tatapani Coalfields ’’: Mem. Geol. Surv. Ind.,
1880, xv, p. 129.
10.—‘‘ Geological Notes (Himalayas) ’’: Records Geol. Surv. Ind., 1880, xiii, p. 83.
11.—‘‘ Paleontological Notes on the Lower Trias of the Himalayas’’: Records,
1880, xiii, p. 94; 1881, xiv, p. 154.
12.—‘‘ On the Geology of the Section between the Bolan Pass in Biluchistan and
Girishk in South Afghanistan’’: Mem. Geol. Surv. Ind., 1881, xviii, p. 1.
13.—‘‘ Report on the Geology of the Takht-i-Suliman”’: Records, 1884, xvii,
p. 175.
lca ett Field Notes ’’: Records, 1885, xviii, p. 57.
15.—‘** Afghan and Persian Field Notes’”’: Rec., 1886, xix, p. 48.
16.—‘ Field Notes from Afghanistan: No. 3, Turkistan’’: Rec., 1886, xix, p. 235.
17.—‘“‘ Field Notes from Afghanistan: No. 4, from Turkistan to India’’: Rec.,
USS 205) Do 1s
18.—‘‘ Field Notes, No. 5, to accompany a geological sketch-map of Afghanistan
and North-East Khorassan’’: Rec., 1887, xx, p. 98.
19.—‘‘ Notice of J. B. Mushketoff’s Geology of Russian Turkistan’’: Rec., 1887,.
XG OP aeligo.
20.—‘‘ Geological Notes (Spiti Himalayas) ’’: Rec., 1889, xxii, p. 158.
21.—“ Geology of the Central Himalayas ’’: Memoirs, 1891, vol. xxiii.
22.—‘‘ The Geology of the Saféd K6h’’: Rec., 1892, xxv, p. 59.
23.—‘‘ Geological Sketch of the country North of Bhamo (Burma) ”’: Rec., 1892,
Xxv, p. 127.
24,.—* Nota on the Central Himalayas’’: Rec., 1893, xxvi, p. 19.
25.—‘*Notes on the Earthquake in Baluchistan on the 20th December, 1892”:
Rec., 1893, xxvi, p. 57. i
26.—‘‘On the Geology of the country between the Chappar Rift and Harnai in
Baluchistan ’’: Rec., 1893, xxvi, p. 113.
THE
GHOLOGICAL MAGAZINE
NEW SERIES. DECADE IV. VOL. xX.
No. VII.—JULY, 1908.
QL EINf dy PASSA Gas.
I.—Nores on Spectmens coutectep By Prorsssor Conus, F.R.S.,
IN THE CaNADIAN Rocky Movuntatns.
By Professor T. G. Bonney, D.Sc., LL.D., F.R.S.
(PLATE XVII.)
Hi most interesting series of specimens in this collection comes
from Desolation Valley glacier, on the southern side of the
Canadian Pacific Railway, and east of the watershed. These are:
(1) A roughly pentagonal slab, about 94” by 7” and from #2” to 1”
thick, of a rather fine-grained quartzite, with some minute glittering
crystals, but giving little or no effervescence with cold HCl. The
surface is crowded with wavy cylinders,' generally slightly flattened,
varying in diameter from about ‘55” to-15” (but commonly about ‘55”).
Fic. 1.—Burrows on quartzite slab, about one-third linear of original size.
Externally they are rather smooth, and I think slight indications of
a ‘shell’ can occasionally be detected, perhaps about one-twentieth
of an inch thick; others seem to consist wholly of white quartzite,
apparently a little purer than that of the underlying slab, but as
1 The markings in all these specimens, unless expressly stated, are in relief.
DECADE IV.—VOL. X.—NO. VII. 19
290 Professor Bonney—Specimens from the Oanadian Rockies.
a rather more flaky yellowish grey material can be detected in the
interstices between them they may have been bored in that material.
(2) Another quartzite slab, roughly oblong, on the average about
dt” by 4” and a little thinner, with a slightly more ferruginous
coating, has practically identical ‘burrows’ (Fig. 1). On the
underside of each is a rather ferruginous coating or glaze, with
some indications of burrows. The material resembles the basal
Cambrian quartzite of North-West Scotland in which worm-burrows
occur, named Scolithus, and figured by Hall,1 as found there and at
the Stiper Stones.? Nicholson? refers the vertical burrows to one
of three genera, Scolithus, Arenicolites, and Histioderma, grouping
the more or less horizontal under the name Planolites (with three
species), which is accepted by Sir J. W. Dawson,‘ who gives a figure
from a slab in the Calciferous Sandstone (Tremadoc) of St. Anne’s,
which appears to be very similar. In the British Museum collection
are similar burrows (unnamed) from the same formation, sent by
Sir W. HE. Logan from the Green Mountains, Vermont. They also
resemble the figure of Planolites (sp.?) figured by Walcott? from
the Olenellus zone. So I think the burrows on these two slabs
may safely be referred to Planolites, but shall not venture to suggest
a specific name.
(3) Three slabs of a generally similar quartzite are irregular in
shape; (a) being about 5” by 4” and 14” thick, (b) about 7” by 34”,
(c) about 5” by 23” (both rather thinner slabs). (a) has some
Planolites burrows on an irregularly undulating surface, with four
rudely parallel tapering marks, rather over 1” long, in general form
something like a Péeroceras spine.’ Similar objects, about seven in
number, but in some cases not so well defined, are found on (0)
(Plate XVII, Fig. 1) with one or two burrow-like marks, but here
some are longer, one or two reaching two inches. Both slabs show
obscure burrows on their under surface. (c) has one of the same
(obscure), and near it a small group resembling the markings referred
by Sir J. W. Dawson” to ‘rill-marks,’ some obscure worm trails,
a bilobed object in relief about 1” by 2” (Plate XVII, Fig. 2), and
possibly the impression of another.® It is a pointed oval in shape,
with a medial depression, like a grain of wheat, which broadens out
so as to produce a flattening at each end. I think the spine-like
marks may be the tracks of some rather large Crustacean, though
I find neither the corresponding set nor the usual central furrow ;
1 Geol. New York, vol. i, p. 2, and pl. i.
2 «¢Siluria,’’ 4th ed., p. 40. They also recall those figured by Matthew (Proc. and
Trans. Roy. Soe. Canada, vol. vii, p. 159, pl. ix) under the name of Chondrites
from the Cambrian (basal) of Acadia.
3 Proc. Roy. Soc., vol. xxi (1872-3), p. 288.
* Quart. Journ. Geol. Soc., vol. xlvi (1890), p. 612.
5 Tenth Ann. Rep. U.S. Geol. Surv., pl. lxi.
6 The form sometimes slightly resembles, though very much larger than, the marks
attributed by Salter to Hymenocaris vermicauda, Prestwich, Geology, vol. ii, p. 35.
7 Loe. cit., p. 545.
8 It has a faint resemblance to the Russichnites of Dawson (loc. cit., p. 597), and
to OU two rather similar (but considerably larger) objects in the British Museum
collection.
Professor Bonney—Specimens from the Canadian Rockies. 291
the others may be produced by an animal of the same group, unless
they are a peculiar duplication of curving burrows. The underside
of the slabs show some ill-marked burrows, and usually the ‘glazed’
surface already mentioned.
(4) A rather rhomboidal slab of greenish-grey quartzite about
3” by 2” by 1” with a brownish glaze on one surface. On this are
little lumps about the size of a small pin’s head, four elongated,
rudely parallel, slightly curving elevations, somewhat resembling
those mentioned above, but barely tapering and so more spine-like ;
possibly forming part of the same set are three others, which,
however, are less regular in shape. On another part of the slab
is a single elevation about as thick as a straw, which may be
a burrow, and two or three near scarcely thicker than stout pins
(once or twice they are in intaglio). Four of these can be detected
underlying the first set and crossing them at an angle of about 60°.
These are more like burrows, but if so the tendency to be parallel is
perplexing. The material of this specimen is more like that of the
next one (5), which is a slab rather rhomboidal in outline, measuring
about 11” by 5”, and roughly 14” thick (Plate XVII, Fig. 3). From
one surface rise a number (about forty) of bosses, dome-like in form,
varying in diameter from about -9” to 1:1”, not quite hemispherical,
owing to a very slight flattening of the upper part of the dome.
A faint ring-like marking, produced occasionally by a slight increase
of the radius, but also by a similar decrease, is often perceptible.
The majority have a slight depression or dimple at the top (occa-
sionally well-marked), as if made by pressure of a blunt-pointed
instrument. In one or two cases the outline of the surface seems
traceable into the slab fora short distance. These domes occasionally
touch one another, once or twice being very slightly flattened at
contact. On the slab also are a few worm-burrows, like those
described above, a couple of which seem to end abruptly against
the exterior of a dome, about as many pass now and then obliquely
over the lower part, and one across the top, where it makes a slight
depression. All the domes and burrows are coatel by a filmy
brownish glaze. The opposite side of the slab consists of a greenish
grey, rather flinty argillite, on which at one place is a flattened,
slightly raised swelling, about an inch each way, something like
a bag in shape, and of slightly different texture. This argillite, in
about 4” or 4”, passes rapidly into a ferruginous quartzite of which
also the mounds consist, but they, together with the burrows, are
apparently surrounded by an irregular thin layer of argillite re-
sembling that on the other side. Besides this slab Professor Collie
1 By the kindness of Dr. Henry Woodward I have examined the very interesting
collection of rock ‘freaks’ (if such a term be permitted) at the British Museum,
but it failed to throw light on these singular structures. They present a certain
resemblance to some of the peculiar globular concretions in the magnesian limestone
of Durham, which occasionally rise in flattened hemidomes, with a similar slight
restriction of the diameter in a horizontal section. But the dents common at the top
of the Canadian specimens are wanting, and the latter show no sign of a concretionary
structure, which is rare in a sandstone, and so far as I am aware unknown in
a quartzite. I find nothing like them in Nathorst’s work (Kong. Svenska. Vetenskaps-
Akad. Handlingar, xviii, 1881, No. 7), nor in Delgado’s Etudes sur les Bilobites, etc.
292 Professor Bonney—Specimens from the Canadian Rockies.
placed in my hands about half of a mound which had been knocked
off its edge, and a fragment of a rather thicker piece of quartzite,
slightly paler in colour, on one side of which were two mounds and
part of a worm-burrow. I have had a slice cut from the former
parallel to the old vertical fracture, and another from the latter in
the same direction and practically through the middle of one of
the mounds going down about # inch into the quartzite. The two
are so similar that one description will suffice. They consist ‘of
grains of quartz, a few being sharply angular, the majority sub-
angular, but a fair number rounded, which are sometimes slightly
enlarged by a secondary deposit of crystalline silica optically con-
tinuous. They exhibit in size and ordering a faint stratification.
I find also two or three small grains of a dull brown tourmaline,
two of them rather prismatic in outline and one included in a quartz
grain. Another slightly more abundant mineral occurs in grains.
rather oval in outline, as well as in not very definitely shaped
crystalline granules included in quartz grains; these have a high
refractive index, are a dull madder-pink or brownish-purple in
colour, and are only faintly pleochroic. At first the polarization
tints seemed also dull, but a closer study showed that their natural
colour masked a real brightness, and the mineral was a dark zircon.
One or two grains of a rather granular dull yellow mineral with
crystalline outline resemble sphene more than epidote. Grains
or granules of an iron oxide, not seldom limonite, are also present,
possibly with two or three of a dark ferruginous rutile. All these
are scattered in a fairly abundant matrix, which is mainly composed
of a minute filmy mica-like mineral, colourless and with fairly high
polarization tints, probably a secondary product after felspar, traces
of which can here and there be detected. In the larger specimen we
find a green filmy or flaky mineral, doubly refracting, barely pleo-
chroic, with rather dull polarization tints, which is probably a variety
of chlorite; in the other one there is less of this, but considerably
more of a minute, prismatic, fairly dark green mineral, probably
an epidote. Thus the microscopic structure, so far from being
favourable, is actually adverse to these mounds having a concretionary
origin. They cannot, I think, be regarded as casts of a Coelenterate
like a ‘jelly-fish’ or any other perishable organism. Professor Collie
and myself came independently to the conclusion that they could only
be casts of pits made by an annelid, as it retreated from the surface.
I remember to have seen pits about this size between tide-marks on
a beach, some of which (I was told) were made by a Solen, others
by a lugworm. These casts, so far as size goes, might belong to
Planolites, with the burrows of which they are associated, but this
annelid generally moves horizontally, being thus distinguished from
Scolithus, which descends vertically. Mr. Walcott, in his “Fauna
of the Olenellus Zone,”’! gives a tube of Scolithus linearis leading to
the top of a piece of sandstone, where are the casts of three cup-like
depressions, and a ‘‘summit view of a group of casts of the cup-like
depressions” (the latter being sometimes more irregular in outline
1 Tenth Ann. Rep. U.S. Geol. Surv., p. 603 and pl. Ixiii.
Professor Bonney—Specimens from the Canadian Rockies. 293
and not very well drawn), which on the whole are very like
the Desolation Valley markings, except that they are barely half
the diameter. Murchison, in the figure mentioned above, shows
the opening of the burrows to be ‘trumpet-shaped,’ and Delgado
(‘Etudes des Bilobites,” pl. xxxix, fig. 1) represents Scolithus
burrows with a saucer-like depression at the top about }” in
diameter, in the middle of which is a low mamelon about half that
width at the base. This would produce a depression in a cast, though
much larger in proportion than those in the mounds which IJ have
described, but that difference may be due to something in the material.
So I think it very probable these mounds indicate * pit-holes’ formed >
by the retreat into the mud of Scolithus or some annelid of similar
habits, and that, as remarked above, the pits were already filled,
perhaps a little stiffened, when Planolites moved among them, or, in
other words, that the pit-making worm lived in the mud and
Planolites rather in the sand. But more evidence is needed before
we can speak confidently on this point.
From Desolation Valley glacier Professor Collie also obtained
four specimens of darkish slaty rock, all probably more or less
calcareous, and one which is practically a limestone, not unlike
some dark varieties in the British Carboniferous Limestone. Of
two other specimens, one has a very pitted surface of a light
reddish colour, resembling a compact dolomitic limestone, perhaps
with some admixture of sandy material. Professor Collie states
that he finds CaC O, with some MgC O,, and it effervesces but little
with cold HCl.1. The second, whiter in colour, but speckled with
dark green (possibly an iron silicate), is a quartzite.
The last specimen brought by Professor Collie contains rounded
and subangular pieces, the former being the larger and occasionally
nearly one inch in diameter, scattered rather sparsely in a purplish-
red calcareous matrix speckled irregularly with the former material,
the weathered surface being very rusty. It consists of carbonates
of lime and magnesia, with iron oxide. A microscopic examination
shows the pale grey enclosures to be a fine-grained dolomitic
limestone containing a few granules of quartz or possibly a silicate ;
the cementing material of the matrix is also a dolomitic carbonate,
but is more irregular in its granular structure. In it two kinds
of grains are thickly scattered; one being quartz, varying from
subangular to well rounded, some of which, at any rate, may be
regarded as wind-worn ; the other are more variable in shape,
enclosed in a dark ferruginous ring, and occasionally almost wholly
stained by it. Some have green centres, which show an aggregate
structure with crossed nicols, and are probably a variety of
glauconite ; others resemble the larger fragments, but are a little
finer grained ; a few apparently retain traces of a reticulate structure
(possibly crinoidal) ; two or three thin elongated or curved objects
may be fragments of mollusca, and one suggests a spiral foraminifer.
There is no precise evidence as to the age of any of these
1 The chemical notes throughout are the results of Professor Collie’s qualitative
examinations.
294 Professor Bonney—Specimens from the Canadian Rockies.
Desolation Valley specimens. Worm burrows and tracks are not
very helpful, but Planolites appear to be commonly found in rocks
belonging to the Cambrian period, ranging from the bottom to
the top. Lithological character also is not the safest of guides,
but I may remark that both the white quartzites and the slabs
with the mounds remind me of Cambrian rocks, the former being
not unlike the basal quartzite of Britain, and the matrix of the
latter being more altered than is usual in a rock belonging even
to the later part of the Cambrian. So I think we may pronounce
the quartzites and argillites from Desolation Valley to be not more
modern than Lower Cambrian, the limestones probably belonging
to a later part of the Paleozoic.
Mount Neptuak (10,500 feet) rises at the head of Desolation
Valley glacier, on the watershed between the Bow and the Ver-
million Rivers, about 12 miles in a direct line from Hector Pass.
A specimen “from the ridge” is a limestone (CaC O,, with a little
MgCO,, a very small amount of insoluble residue, and some
carbonaceous matter). In colour it is a pale brownish grey, mottled
rather irregularly, and in about equal quantities with a darker shade
of the same. The microscope shows it to be a very fine-grained
dolomitic limestone, mottled by another rather more coarse, its
grains varying about :005 inch in diameter. The finer part is once
or twice traversed by a sharply zigzagged dark line suggestive of
fracture, and the coarser seems to run up into a crack in the finer
material, the latter corresponding with the darker parts of the
rock ; it also contains a few thin fragments, straight, or hooked,
or more or less oval, probably organic, perhaps molluscan. I suspect
that the finer-grained rock has been brecciated én siti and sub-
sequently cemented by infiltration.
The remaining specimens come from the northern side of the
Canada Pacific Railway, and at a much greater distance from it.
Mount Freshfield (about 10,900 feet) is on the watershed where
it has bent much to the west. It drains on one side to the Bush
River (South Fork), on the other to the Blaeberry Creek, which
joins the Columbia River. From the Freshfield Glacier comes
a pebble, possibly a rather crushed and decomposed diabase, con-
taining perhaps a speck of sodalite. From near the summit of
the mountain are two limestones, each rather curiously marked,
one being yellowish (Ca C O, with a little SiO,), indicating, I think,
local brecciation and recementation; the other (yielding a white
residue and no Mg(Q) possibly due to a similar cause. They have
a general resemblance to later Paleozoic limestones.
A specimen from the Bush Pass near Mount Freshfield is an
impure limestone (CaCO, with Mg O, and some SiO, or Al, Os) ;
it affords dubious traces of organisms and may be Paleozoic.’
1 In 1900 Professor Collie (Geogr. Journ., xvii, 1901, p. 268) brought a few
specimens from pebbles in the bed of the Bush River, some distance away to the
west. One is a limestone with oolitic grains recrystallized; another contains
fragments of organisms, ill preserved; two show a coral which, according to
Mr. E. T. Newton, F.R.S., probably in one case, certainly in the other, belongs
to the genus Diphyphyllum.
Professor Bonney—Specimens from the Canadian Rockies. 298
A specimen from a “washout beneath Forbes,” at the junction
of the stream from the Freshfield Glacier with the valley from Bush
Pass, which runs ultimately into the Saskatchewan River, is
a black cherty-looking rock, harder than the knife (insoluble in
HCl, but with faint tracesof CaC O,). This, under the microscope,
exhibits rather more minute granules and rhombs of a carbonate
(probably dolomite) than I should have anticipated; its general
colour being a very pale brown. The slice is crowded with small
clear organisms, about :005 inch in length, sometimes cylindrical,
which on examination with a high power prove to be siliceous.
The material is occasionally doubtfully colloid, more often of minute
crystalline granules, with occasional local replacement by calcite
or dolomite. Believing these to be sponge spicules, I submitted the
slice to Dr. G. J. Hinde, F.R.S., to whom I am indebted for the
following note: ‘These are rod-like bodies, showing traces of an
axial canal, which I feel certain are sponge spicules, and I should
also refer the confused mass of fragmentary rods to spicules, but
they are now so much altered that it is impossible to recognize if
any of them belong to lithistids” [I had suggested the possibility ].
He adds: “I have a slice of chert or cherty limestone from the
Durness Limestone of Sutherland which is not unlike your section,
but the spicules are more distinct and the rhombs of calcite or
dolomite less crowded than in the Canadian rock.” The slice is
traversed by wavy dark-brown lines (? infiltrated cracks).
The specimen from a peak south-east of Mount Lyell and west
of Mount Sullivan, at the head of the Valley of the Lakes (which
drains to the North Fork of the Saskatchewan), is a calcareous
conglomerate (Ca C O;, no Mg O), consisting of rather flat, subangular
to rounded fragments, none exceeding ‘75 inch, of a pale grey
compact limestone in a yellowish calcareous matrix. Hxamination
with the microscope shows the fragments to be varieties of a limestone,
generally slightly dirty in aspect, occasionally a little speckled with
a dark brown (?bituminous) material, and crowded with minute
fragments of organisms (not to be identified with certainty) and
small round grey spots (about -(025 inch in diameter), probably
oolitic. There are also a few small grains of quartz. The matrix
is more or less stained with limonite, contains many fragments of
organisms, similar but larger; some showing traces of prismatic
structure, and probably molluscan; some perhaps Brachiopods ;
some also possibly calcareous sponge spicules.
Mount Forbes (about 12,000 feet) is also to the south-east of
Mount Lyell, but to the south of Mount Sullivan. It should be noticed that a spherical surface also, if it cuts a sphere at all, will
necessarily have a circular outcrop. No other form of surface, I believe, has a similar
outcrop, excepting only in certain definite positions. A cylindrical surface, for example,
will crop out in the form of a circle, if its axis coincides with a diameter of the sphere,
but not otherwise. If the thrust-plane be a portion of a spherical surface, it is
impossible to determine its dip from an inspection of its outcrop alone.
DECADE IV.—VOL. X.—NO. VII. 20
306 James Durham—Post-Glacial Beds at Dundee.
which the basal thrust-plane must make with the surface at its
outcrop.
It is not, however, to be expected that the angle thus deduced
from the form of the mountain chain will agree with the dip of the
boundary fault along its foot; for in a modern mountain chain the
actual base will seldom be exposed, and the faults which are visible
at the surface probably bear the same relation to the main thrust-
plane that the minor thrusts in the North-West Highlands bear to
the major thrust-planes of that region. It is only when the
mountain chain has been dissected to its very base that we can
hope to see the surface on which the main movement occurred.
If I were to attempt, on this view, an ideal representation of the
Himalayas, I should draw, some little distance below Middlemiss’s
Section VI, a thrust-plane making an angle of 14° with the
horizontal. The resemblance of the structure of the chain to
that of the North-West Highlands would then be conspicuous.
Most of the faults which are visible at the surface would appear
as minor thrusts, but it is possible that the great thrust-plane which
brings the crystalline schists upon the later beds was at one time
the basal plane of the range.
I have no desire to argue that all mountain ranges lie upon the
outcrops of thrust-planes, or that there is necessarily a thrust-plane
wherever Professor Sollas has drawn one of his small circles. But
it remains certain that if a thrust-plane is a true plane, its outcrop
on the globe must be an arc of a circle, and that some mountain
chains are defined along their convex margins by thrust-planes.
Here, then, we seem to have an explanation of some of Professor
Sollas’s small circles.
Postscript.—After the proofs of this short note had left my
hands it occurred to me that the Calcutta earthquake of 1897 might
throw some light on the existence of the basal thrust-plane which
I have imagined in the Himalayas. It appears from Mr. Oldham’s
valuable memoir on the subject that the earthquake originated in
Assam and not in the Himalayas themselves; but it is interesting
to find that Mr. Oldham compares the structure of the Assam Hills
with that of the North-West Highlands of Scotland, and believes
that the earthquake was caused by a movement along a major thrust-
plane of low dip, accompanied by displacements along the more
steeply inclined reversed faults which reach the surface.
V.—Post-Guactat Breps at DUNDEE.
By James Duruam, F.R.S8.E., F.G.S.
IE the recently published volume of the Memoirs of the Geo-
logical Survey of Scotland, “The Geology of East Fife,” by
Sir Archibald Geikie, it is argued that since the time when the
100 feet terrace was under the level of the sea there has been no
depression of the land in the Firth of Tay, only ‘a continuous
chronicle of gradual, if intermittent, uprise” (p. 321); also that
James Durham—Post-Glacial Beds at Dundee. 307
“no trace has survived of any late deposit overlying the peat, so
that we cannot be absolutely sure of the position which this sheet
of vegetable matter would occupy if all the Post-tertiary deposits of
the district could be grouped in chronological order” (p. 318).
In the face of this statement by such a high authority if seems
to be very desirable that the details of a section in post-Glacial beds,
exposed in digging the foundations of the new Post Office in Dundee,
should be recorded in the pages of the GrotogicaL MaGazine.
As the readers of this Magazine are probably not all familiar with
the recent geology of the Firth of Tay, it may be well to state briefly
the chronology of these comparatively recent deposits heretofore
usually accepted.
At the close of the Glacial Period, or at least when the glaciers
had mostly withdrawn from the sea-level, the land stood more than
100 feet lower than at present; the floor of the sea at that time is
represented now by a much denuded plateau of sand and gravel,
and by a well-worn beach shelf, which indicates a prolonged rest
of sea and land at that level; besides the sand and gravel of which
the plateau is mainly formed, excavations often bring to light huge
boulders which could only have come into their present position by
being floated there, which would seem to show that some of the
fading glaciers at times reached the sea and detached masses of ice
sufficiently large to float these boulders, and, melting, dropped them
where they are found.
A slow but apparently uninterrupted upward movement of the
land then took place, until it stood about 50 feet lower than at
present, when another prolonged rest is indicated by a well-marked
beach shelf; between that and the present sea-level the most im-
portant beach is that at 25 to 30 feet above the present, but between
these beaches there are indications of what seems to have been
relatively short rests in the movement. During the long time since
the 100 feet terrace, as it is called, was under the sea, denudation
has removed a very large proportion of it; especially is this the case
in estuaries and river-valleys.
In the Firth of Tay a forest grew on the denuded surface of the
100 feet terrace beds. This forest is represented by a bed of bluish
clay in which are entombed roots, trunks, and branches of trees
with hazel-nuts; also fragments of insects and sometimes bones of
deer are found in this bed; the nuts are much flattened, as if they
had been subjected to great pressure under a superincumbent load.
This forest bed is found at different levels all over the Firth of Tay,
and at some points is seen to pass under low water. This used
to be taken to prove that the land stood higher in the time of the
forest than it does now, and naturally so, as it is difficult to imagine
a luxuriant growth of trees and bushes flourishing fourteen feet
below high-water mark in this broad arm of the sea.
In the upper parts of the Firth of Tay and the Harn another bed
or series of beds is found rising some 30 or 40 feet above the
present sea-level ; these beds consist of clay, sand, and silt, and are
known as the Carse Clays.
308 James Durham—Post-Glacial Beds at Dundee.
_ Now it is clear that if the Carse Clays are laid down on the top
of the forest bed, not only had the land stood higher than at present
in the first instance, but had been subsequently depressed at least
to the level of the top of the Carse Clays, as these are evidently
sedimentary deposits in the waters of the Firth.
_ -It is stated on the most reliable authority that in excavations
and well-borings in the Carse of Gowrie the forest bed has been
repeatedly penetrated. (See Professor James Geikie’s ‘“‘ Prehistoric
Kurope,” pp. 391, 392.)
In digging the foundation of the new Post Office at Dundee,
a section was exposed which seems to throw a valuable light upon
the question as to the succession of these beds, for here we have
“deposits of the district grouped in chronological order.” The
situation of this section is about a quarter of a mile back from
the natural foreshore of the Firth (docks and similar works extending
far out into the estuary) ; between the section and the shore a ridge
of rock runs for a considerable distance parallel to the margin
of the Firth; like the post-Glacial beds to the north of it, it is
completely covered by buildings, and like them is only exposed
during excavations in connection with alterations and rebuilding
in this the centre of the most ancient part of the city.
The level of the street in front of the Post Office is 38 feet above
Ordnance-datum. Allowing for the thickness of the blocks and
bedding of the street, the top of the section is approximately 36 feet
above that base-line, just about the average height of the Carse Clays.
in the upper part of the Firth. As the total thickness of the beds
exposed would be about 25 feet, the bottom of the section would be
a little above the present reach of the tide.
— Se OO CE
COARSE SAND.
— eee
ie
:
|
PEELE
Bizz LZ; CLAY.
WAVE ow ®- woe BL Wai ff NEW FOREST-SED.
CLAY.
‘L333 Vi
Yt
LZ
© fans ra ; FOREST BED. 6-8 INS.
COARSE GRAVEL.
o° 100 FEET TERRACE.
Section exposed in digging the foundations of the new Post Office, Dundee.
The excavation revealed the following succession of strata :—
At the bottom some five or six feet of coarse gravel, the denuded
remains of the 100 feet terrace, then six or eight inches of the far
extending forest bed, as usual much compressed; this is succeeded
by 11 feet of clay, above which is 84 feet of coarse sand.
I was indebted to the Inspector of Works for the measurements,
so that they may be accepted as absolutely reliable.
Reviews—Dr. A. W. Rowe—Zones of the White Chalk. 309
' An interesting and previously unobserved feature is revealed by.
this section of the Carse Clays: an upper bed of trees and bushes’
occurs a little above the middle of the clay, the roots extending for
a considerable distance downwards, while the evenly bedded clay
of more recent deposit completely buries it several feet deep before’
the conditions that caused the deposit of the coarse sand supervened. ’
The occurrence of this upper forest bed would seem to indicate’
that there had been an interruption of the subsidence, or even’
re-elevation of the land, during the deposition of these clays, to.
admit of the growth of the trees and shrubs that form this bed.
That there is good ground for assuming that the gravel exposed’
at the bottom of the section represents the 100 feet terrace is
supported by the records of a deep well-boring made a little to the
westward of the Post Office. After passing through similar beds’
of sand and clay and some 10 or 12 feet of gravel, it, before entering’
the rock, encounters some 8 or 10 feet of tenaceous blue clay,’
undoubtedly the Till resting on the surface of the Andesite rock of '
the district. Pav ge
With the well-boring and the Post Office excavation, we have’
a complete series of the Glacial and post-Glacial beds superimposed
one on the other: Till, 100 feet terrace, forest bed, and Carse Clays.’
It seems to me that here we are “‘absolutely sure of the position
which this sheet of vegetable matter does occupy.”
d5% Ja W/ a6 JE WA, Se
1.— Tue Zones or tHe Ware CuHatk or THE ENeGLisH Coast.
By A. W. Rowe, M.D., F.G.S. Parts I (Kent and Sussex),
II (Dorset), and III (Devon); with plates and sections..
Published in the Proceedings of the Geologists Association,
vol. xvi (1900), vol. xvii (1901), and vol. xviii (1908).
(PLATES XV anp XVI.) }
ITH the publication of his third paper (on the Chalk of the
Devon coast) Dr. Rowe has completed his description of the
four chief accessible sections through the Middle and Upper Chalk
which are to be found in the cliffs of our southern coast. His papers
are doubtless in the hands of most of those who are interested in the
Chalk and its fossils, but there may be a few readers of this Magazine
both at home and abroad who have not seen them, and in any case
it seems fitting that such a series of papers should receive some
notice, if only because they deal so fully with the zonal distribution
of fossils in the Chalk of Southern England that they merit attention
both from the paleontologist and the geologist.
In the introduction to his first paper, Dr. Rowe is careful to
define the point of view from which he attacks the subject. He says:
1 [Permission to reproduce the two plates which accompany this article (Plates XV
and XVI) has been granted by Dr. A. W. Rowe, F.G.S., the author of the paper,
Professor H. E. Armstrong, F.R.S., who is the author of the photographs, and by
the Council of the Geologists’ Association, who published Dr. Rowe’s memoir.—
Epir. Grou. Mac. ]
310 = Reviews—Dr. A. W. Rowe—Zones of the White Chalk.
‘the writer pins his faith to Zoology, and to Zoology alone, for while
it is true that broad lithological features give us a natural division-
line between certain zones in some localities, it is equally clear that
these same features fail us in the case of identical zones in other
districts; but the fossils never fail us if we collect with sufficient
care.’ This is doubtless true in the case of a coast-section, where
a long tract including several zones is exposed and every bed is
accessible, but it is not true of inland sections, which are usually
isolated quarries or short railway cuttings, often much obscured by
talus, and only accessible at certain points. In such places fossils
do often fail us, as Dr. Rowe will find if he ever essays to carry his
researches inland.
The value of Dr. Rowe’s work Jies in his demonstration that an
ordinary cliff-section of Chalk affords ample material for the estab-
lishment of zones and for their exact local delimitation. Incidentally,
of course, he has recorded much valuable stratigraphical information,
and has largely increased our knowledge of the fossils of the English
Chalk. There are, indeed, few workers who are both willing and
able to devote themselves to the systematic collecting of fossils
from every accessible foot of a long series of beds; few men would
voluntarily spend all their vacations in collecting thus exhaustively
from one set of beds, while members of the Geological Survey cannot
do so, because they are primarily surveyors and have to give most
of their time to the work of mapping. If instead of a mere fossil-
collector the Survey had a field-paleontologist, a man of scientific
training who ranked equally with the surveyors, the descriptive work
of the Survey would undoubtedly be improved.
To produce good stratigraphical work there should be organised
collaboration between the surveyor and a paleontologist, unless the
two capacities are combined in one man. In appreciating Dr. Rowe’s
work we must remember that he does not put it forward as strati-
graphical work ; he calls his papers zoological, but inasmuch as they
deal with zones they are essentially stratigraphical, and only want
stiffening with a little more lithological detail to make them complete
stratigraphical studies. As it is, his descriptions are frequently
incomplete because he omits to notice obvious lithological peculiarities.
Thus the zone of Rhynchonella Cuviert near White Nothe is dismissed
in eight lines, and the same zone as shown at Mupe Bay in six lines,
although its lithology is abnormal and interesting. I point this out
simply because the work he has done is so good and so full of detail
that one regrets he did not include what would have made it a finished
study.
In reviewing the papers which have suggested the above remarks
we shall briefly notice the salient points of each. In his first (on
the Chalk of the Kentish coast) he commenced with the Margate
Chalk, and showed that the zone of Marsupites is divisible into two
bands or sub-zones, a lower characterised by Uintacrinus and an
upper to which Marsupites is restricted, and he has since found that
this subdivision holds good throughout the south of England. The
next critical point was the discrimination of the zones of Micraster
Reviews—Dr. A. W. Rowe—Zones of the White Chalk. 311
coranguinum and M. cortestudinarium, and this he was only able to
accomplish after a detailed study of the genus Micraster, the results
of which were published elsewhere. He places the junction, not
where Micraster precursor and M. cortestudinarium are first found in
the descending succession, but where certain special forms of these
species come in and are associated with Holaster placenta, H- planus,
and some other fossils.
In the same way a careful collecting of fossils foot by foot enabled
him to fix approximate limits to the zones of M. cortestudinarium and
Holaster planus. Here I may remark that Dr. Rowe seems to have
been under the impression that the term Chalk Rock had been applied
by some previous writer to a certain part of the zone of Hol. planus
at Dover; possibly he misunderstood some expressions in Mr. W.
Hill’s paper on the Middle Chalk of that place; in any case Mr. Hill
and I agree with him that no true Chalk Rock exists there.
Dr. Rowe’s work in Sussex was fruitful in new results. The zones
of Holaster planus, Micraster cortestudinarium, and M. coranguinum
were defined and distinguished by means of the essential features of
the tests of the Micrasters ; but though it is very interesting to know
that this can be done by reliance on the forms of Micraster alone, it
is obvious that some other means of delimitation must be adopted
inland when a sufficient number of Micrasters cannot be obtained,
and I doubt whether the zones will remain permanently as defined
by Dr. Rowe. This, however, is a question for the future.
With the zone of Marsupites we are on safer ground; neither
Uintacrinus nor Marsupites had previously been found on this coast,
in spite of special search for them. Professor Barrois had assigned
far too great a thickness to this zone in Sussex, and he had never
properly defined it. The actual limits within which Dr. Rowe
found the plates of these Crinoids was a thickness of 774 feet, but
above this there is a thickness of 20 feet which he regards as more
properly included in this than in the overlying zone, and I have his
authority for stating that this 20 feet was omitted by mistake in the
tabular measurements on pp. 333 and 836. The total thickness
of the zone is therefore 974 feet, and the exposed portion of the
Actinocamaxz quadratus zone at Seaford Head only 150 feet.
Finally, in this paper he established the zone of Actinocamax
quadratus on a firm basis as one of the chief zones in the English
Chalk, showing that it contains a fauna which is distinct from that
of the zone of Marsupites below, and from that of Belemnitella
mucronata as developed further west. At the same time he pointed
out that the prevalent Belemnite is not A. quadratus, but A. Merceyt,
which he has since identified with the A. granulatus of Blainville.
Dr. Rowe’s second instalment was on the Chalk of the Dorset
coast, and this paper is illustrated by eight excellent photographs of
the cliffs, and two maps on the scale of 6 inches to a mile, drawn by
Mr. C. D. Sherborn. The plates show what can be done by means
of photographs and key-slips to illustrate the stratigraphical detail
of a cliff-face, and a comparison of the text with that of the Survey
memoir on the same area shows how much more information can be
elicited by a careful collection of fossils from the Chalk.
312 Reviews—Dr. A. W. Rowe—Zones of the White Chalk.
‘ Dr. Rowe commences with an excellent description of the cliff>
section from White Nothe to Bats Head, which comprises all the
zones of the Middle and Upper Chalk from the zone of Rhynchonella
Cuvieri to that of Actinocamasx quadratus. He points out that the
layers of yellowish green-coated nodules which had been called
‘Chalk Rock’ really occur in the upper part of the Terebratulina
zone, and in no way represent the Chalk Rock. To my own know-
ledge it is just the same in the Isle of Wight; in both areas the
equivalent of the Chalk Rock is to be found in the lower part of
the zone of Holaster planus, which consists of nodular chalk
without any beds of hard limestone. Hach zone in the White
Nothe section is defined by the range of its characteristic fossils,
and of the Acé. quadratus zone no less a thickness than 320 feet
comes in without any sign of the still higher zone of Belemnitella
mucronata, although that is found inland.
~ The zonal details of all the other accessible cliffs are treated in the
same way, i.e:, those of Durdle Cove, Man of War Cove, Lulworth,
Mupe Bay, Arish Mell, and Worbarrow Bay; and though in some
places the Chalk is so crushed that measurements are of small value,
the determination of the zones which enter into the composition of
these cliffs carries our knowledge much beyond that of any previous
memoir. Finally, the cliffs which extend from Ballard Point to
Studland Bay are described as fully as the difficulties of access will’
permit, and the limits of the zones of Marsupites, Act. quadratus, and:
Bel. mucronata in them are for the first time correctly indicated.
_ Part III of these studies, being a description of the Chalk of the
Devonshire cliffs, was published in May of this year, and is in some
respects the most interesting, as it is certainly the most fully and
beautifully illustrated of the series, for it includes twelve plates
showing portions of the cliffs between Lyme Regis and Branscombe,
and each is made illustrative of the zonal geology by means of
a key-slip.
The general stratigraphy of the Devon Chalk has been known
since the publication of Professor Barrois’ “ Recherches ” in 1876,
for he was the first to ascertain that the greater part of the Lower
Chalk is absent, and that the beds which include the Beer Stone:
belong to the Turonian or Middle Chalk. More detailed and accurate
knowledge of the structure of these cliffs has been in my possession
for many years, but being destined for a Geological Survey memoir
its publication has been long delayed. Meantime Dr. Rowe has
visited the coast, and has explored the beds in some places more
minutely than I was able to do, the result being an excellent guide’
to the Chalk of Devonshire.
Beginning with the Pinhay cliffs near Lyme Regis, he shows
that they exhibit good sections of the zones of Rhynch. Cuvieri,
Ter. gracilis, Hol. planus, and Iicr. cortestudinarium, and his careful
collecting of fossils has enabled him to delimit the zones in this
section more accurately than any previous observer. The same
succession is found again at Beer and at Beer Head, and I agree with
him that the summit of the zone of Micraster cor testudinarium is not
_ IV. Vou X.
whi
zones of the Middle ana “Dppere Challe from the zon
Cuvieri to that of Actinocamax quadratus. He points ou
layers of yellowish green-coated nodules which had “b
*Chalk Rock’ really occur in the upper part of the Terebi
_ Zone, and in no way represent the Chalk Rock. To my own know=
ledge it is just the same in the Isle of Wight; in both areas
equivalent of the Chalk Rock ‘is nit corel cdo i
the zone of Holaster planus, which consi
without any beds of hard op lepias ai a Zone
Nothe section is ae eu
- and of tMetaet: pM ddeatus bone 1990h SHS uIafibdil
se aaa aikeuirey sion*o the still aig zone of Beles
UCI It ous, H that is Found inland.
sa {data Ag) Lum
sailieiaasaie rotdajse—ef Du dle
Mupe Bay, Arisly Mell, an
ane the Ws
peryit, and his Nesteat aul zones of Marsypites, Act. quadratug, and:
bel. mucronate shag are for the first, j mje correctly indicated} snSeiloeaT
pete Pissription n of the Boe the
beautifu oH bri Tig
Srowms ortions “oft the ol iis
and each aig.gipee—this We
a key-slip. searansy)
The general stratigraphy of t es Chali.haa beam dnaro
since the.publication of Professgr Bartois’ “ Recherches ” in 1876, a
for he was the fibsedepoacertain /that the greater part of the Lower’ ‘.
Chalk is absent, and that the/beds which include the Beer Stone .
belong to the Turonjian or Middle Chalk. More detailed and accurate
knowledge of the structure of these cliffs has baametren my possession’
for many years, but being d¢gstined for a Geological Survey memoir
its publication has been\long delayed. Meantime Dr. Rowe has’
visited the coast, and has\explored the beds in some places more
minutely than I was able to do, the result being an excellent guide’
to the Chalk of Devonshire.
Beginning with the Pinhay~cliffs near Lyme Regis, he shows
that they exhibit good sections of the zones of Rhynch. Cuviert,
Ter. gracilis, Hol. planus, and Micr. cortestudinarium, and his carefull
collecting of fossils has enabled him to delimit the zones in this’
section more ey than any ee eet The same’
succession is 49 af Peo ana Bea Beh d ppd. Lagree with’
of Micrdste
_Vmitdthat the ‘ Wad ths ZONe * EE eo is not
i
E of gape i
CON) ae inSain
—=
PLATE XV
VoL. Ko
Dec. IV.
1908.
GEOL. Maa.
BEER HEAD, FROM THE WEST.
Bemrose, Collo.
bly
-
i
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WAX: aLvid “% TOA ‘Al “03d “€061 “9VI “1045
snoS-e2ilia6137 fynlends
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eee eee {oS = =
— 8 P bas.o.9 gnibivib onilaniftietd x se
aifiondyT bas rein 2snoN baibirib oil initiel = \
1, 2 Nee ye \ <
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gna \-i1sivua.A eee ee ge
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ie
Reviews —Geological Survey of England— Leicester. 313
veached at any place along this coast, and that evidence of the higher
zones is only to be found in the flints of the overlying gravels.
' The interesting section of Beer Head and Hooken Cliff is fully
described, and is illustrated by four plates which are excellent both
from an artistic and geologic point of view. Of these plates our
readers will be able to judge from the two examples which are here:
introduced. The first (Plate XV) is a view of Beer Head itself,’
a sheer cliff of nearly 300 feet in height, of which Dr. Rowe says,
“no section on this coast gives one so diagrammatic of the zonal’
boundaries as Beer Head, for none is so complete.” The second:
(Plate XVI) shows the Hooken Cliff, behind the great Southerndown
landslip; this rises to a height of 400 feet, and presents a face of
beautifully weathered beds. Here, by means of a convenient talus-
slope, a continuous section can be examined through a large part of
the Middle Chalk, the Cenomanian (24 feet thick at this point), and’
the upper half of the Selbornian (Upper Greensand). At this
locality one of the most interesting phenomena is the local break
and gradual disappearance of certain beds in the western part of
Hooken Cliffs. Dr. Rowe is quite correct in stating that about
70 feet of Chalk is missing above Mitchell’s Rock, but he is
mistaken in thinking that the whole of the Cenomanian is also
absent ; I found the basal part of the Cenomanian limestone both
in Martin’s and in Mitchell’s Rock, and particulars of the beds
which compose these fallen masses are given in a memoir which is
on the eve of publication. I also differ from Dr. Rowe in his
reading of the zones in the Berry Cliffs. But these are minor
points and do not detract from the great value of his paper. Like
each of the other papers, it concludes with a ‘ zoological’ summary
and with a tabulated list of fossils showing the zonal distribution of
each species.
The careful and thorough manner in which Dr. Rowe has worked
the South Coast sections merits our hearty recognition, while the
illustrations are deserving of the highest praise. It is satisfactory
to know that the Chalk cliffs of Yorkshire will soon be similarly
described and illustrated.
For the benefit of those who are not members of the Geologists
Association, it may be mentioned that each of Dr. Rowe’s papers can
be purchased separately from Mr. E. Stanford, the price of Part I
being 1s. 6d., that of Parts II and III being 3s. each.
A. J. Juxes-BRowne.
Memoirs OF THE GroLoGIcAL SuRVEY oF ENGLAND AND WALES.
IJ.—The Geology of the Country near Leicester (Explanation of
Sheet 156). By C. Fox-Srraneways, F.G.S. 8vo; pp. vi and
122, with 15 text illustrations. Printed for H.M. Stationery
Office. London: EH. Stanford, Long Acre (or of Messrs. Dulau
& Co., 87, Soho Square, W.), 1903. Price 3s.; price of Sheet-
Map 156, colour-printed, 1s. 6d.
3814 Reviews—Geological Survey of England—Leicester.
HANKS to the energy of the Director, Mr. J. J. H. Teall, there
has been a steady output of memoirs by the staff of the
Geological Survey, as may be seen by reference to this and to the
June Number of the GxonocicaL Magazine (pp. 269-277).
In the present memoir, by Mr. C. Fox-Strangways, we have
a description of the geology embraced in the area contained in
Sheet 156 of the new series one-inch Map of England, which covers
parts of central and eastern Leicestershire and a part of Rutland.
Considerable changes have been made in the delineation of the
geology of this part of the Midlands, due principally to the use of
larger scale maps, which has enabled the outcrop of. the granite and
other older rocks in the neighbourhood of Mountsorrel to be shown
with more exactness than was possible on the old maps of smaller
scale. The outcrop of the Rheetic beds has also been traced, and
slight modifications have been made in the mapping of the Keuper
Marl; the subdivisions of the Middle Lias, too, are now shown with
greater precision.
The Drifts, which cover so large an extent of the area embraced
in this map and memoir, have been surveyed in detail for the first
time; they form the most striking feature of the map, and well
exemplify their plateau-like character.
The alluvium, both in the main and smaller valleys, has been
carefully and accurately traced, and tends to bring out more clearly
the drainage system of the country. The river terraces are also
shown.
A new feature, which will be observed on the colour-printed map,
is the introduction on the margin of a longitudinal section from
south-east to north-west, showing the general structure of the
ground, taking in the Charnwood rocks and Mountsorrel Granite
in the north-west, with the Keuper Marls about Syston, followed
by the Rheetic beds and Lower Lias Limestone and shales, with the
Middle Lias sandy shales and rock-bed resting on it, and also
occasional outliers of Inferior Oolite forming the high ground of
Robin-a-Tiptoe, Whatborough Hill, and other eminences (see also
page-section given at p. 5 of memoir). Everywhere between the
main valleys and their tributaries the Great Chalky Boulder-clay,
with intercalated beds of sand and gravel, together with the Upper
and Lower Older Boulder-clay, cover the country in wide sheets.
The district is thus essentially a clay country, the Keuper Marls,
Lias Clays, and Boulder-clay all contributing to its argillaceous
character, and influencing its soils from an agricultural point
of view.
The older formations that come to the surface within the limits
of the map occupy a very small space, but they have been proved
to extend further beneath the newer rocks at Leicester and else-
where. They include a small outcrop of the pre-Cambrian slates
of Bradgate Park and the intrusive granite and other rocks of
Mountsorrel, which form the fringe of the Charnwood Forest
district. The principal formations, however, are the Trias and the
Lias, which practically cover the whole of the district.
Reviews—Geological Survey of England—Leicester. 315
The following table gives a list in descending order of the sub-
divisions of the strata :—
Recent and Alluvium.
Post- Glacial. { River-gravels.
Valley -dritt.
RECENT Chalky Boulder-clay, with intercalated
and beds of sand and gravel
PLEISTOCENE. Glacial. Older Boulder-clay (upper part).
Quartzose sand.
Older Boulder-clay (lower part).
Older sand and gravel (?).
Inferior Oolite. Northampton Sands.
Upper Lias. Shales. ;
Marlstone rock-bed (zone of Ammonites
. F spinatus).
TEER. iiding, | Mule Lacs sh aes and clays with ironstone,
etc. (zone of Am. margaritatus).
Lower Lias. Lower Lias shales, with limestones in
the lower part.
Rheetic, Rheetic beds.
TRIASSIC. Keuper. . Keuper Marl with lenticular sandstone
beds, and bands of gypsum.
rocks.
Slates, hornstones, and agglomerates of
\ Charnwood Forest.
The Keuper Marl crops out along the Soar Valley, covering
a considerable area, but the most extensive formation is the Lower
Lias, which crosses the centre of the district; between these
is a narrow band of Rhetic shales, which has now been mapped
for the first time. This is followed by the Middle and Upper Lias,
which cover the eastern part of the district, and form the higher
ground found in that direction. A few isolated hills of Inferior
Oolite rise here and there above the general mass of the
Upper Lias Clay. Finally, the whole of these strata are more
or less covered by Boulder-clay and sands, which have somewhat
altered the general character of the country.
The soil of the country, being in the main derived from the
underlying formations, is mostly clay of a very retentive character.
It is diversified here and there by beds of sand and gravel, which
render it much lighter. This is particularly the case with the
alluvial gravel that occurs along the margin of the Soar Valley,
especially about Syston. In the eastern part of the area the rock-
bed of the Middle Lias, where not covered by Drift, also forms
a light rubbly soil, which is the best arable land in the district.
In consequence of the large proportion of heavy clay land the
greater part of the country is devoted to grazing purposes, and
is noted for its extensive pastures and its excellence as one of the
finest hunting countries in the kingdom.
Although there is no coal-mining in the area now under
consideration, the proximity of the coalfields to Leicester, and their
early connection by one of the first railways made in the kingdom,
have enabled that town to become an important manufacturing
centre.
or Charnian.
PRE-CAMBRIAN
ARCH AN.
ee of Mountsorrel, and associated
316 Reviews—Geological Survey of England—Leicester.
A large industry, and one which has greatly increased of late
years, is the quarrying of roadstone. This is actively carried on’
at Mountsorrel, where the granite forms an excellent material both
for mending roads and for pavements; it is also used in the
preparation of artificial flagstones. These quarries are very
extensive, and being connected by branch lines with both the
Midland and Great Central Railways, a large amount of road-
metal is sent away to other districts.
The Keuper Marl is extensively used along the Soar Valley for
the manufacture of bricks, and has entirely superseded those made
from the Glacial and Liassic Clays, which were worked to a small
extent locally for this purpose.
The rock-bed of the Middle Lias contains a certain amount of
ironstone and was formerly worked at Tilton, but it does not appear
to have been profitable.
Gypsum occurs in the Keuper Marl at Thurmaston, and other
bands have been met with in borings; but it has not been used
commercially in this district, although extensive works exist to
the north between Kegworth and Gotham. :
The limestone bands in the lower part of the Lias, from which
the well-known cement at Barrow is made, are sar eae for lime
at Kilby Bridge, but the beds are more shaly and impure than at
Barrow.
Building-stone is also a scarce article, the Lias rock-bed being’
generally too soft and friable for the purpose. The Middle Lias
yields some hard fossiliferous blocks (called ‘ jacks’), which have
been used on the Melton and Market Harborough Railway. in
the construction of bridges, which appear to stand fairly well. —
A carefully prepared catalogue of fossils obtained from the
Trias, Rheetic, and Lias formations of Leicestershire and Rutland
(pp. 95-115), giving the range and localities for each, will. be
found of great use to the paleontologist.
A long list of borings and well-sections is recorded. There are
two well-printed half-tone plates: (1) “ Hawceliff Hill, Mountsorrel,
Crags of Granite, showing horizontal bedding”; (2) “Railway
Cutting at Tilton, showing Upper Lias Shales resting on the Rock-
bed of the Middle Lias.” The other thirteen illustrations are in
the text (a few of them being from Professor J. W. Judd’s memoir
‘Geology of Rutland,” prepared i in the age of woodcuts).
The new map (No. 156) of which this memoir is a description
is one of the best and most successful examples of colour-printing
yet issued by the Geological Survey; the arrangement of the
colours (which of course corresponds with the general arrange-
ment of the drainage-lines of the country) giving this sheet
a most pleasing and artistic appearance, the colours producing
a very harmonious effect.
III.— The Geology of the Country around Reading ; being the
Explanation of Sheet No. 268. By the late Joun Horwoop
Buare, Assoc. M. Inst.C.E., F.G.8., with contributions by
Reviews—Geological Survey of England—Reading. 317
Wm. Wairtaker, B.A., F.R.S. Edited by H. W. Monckton,
F.L.S., F.G.S. 8vo; pp. 92, with 13 illustrations in the text.
Printed for His Majesty’s Stationery Office by Wyman & Sons.
London: E. Stanford, Long Acre (or Dulau & Co., 37, Soho
Square, W.), 1903. Price 1s. 6d.
HE author of this memoir, Mr. John Hopwood Blake, jomed the
Geological Survey in 1868, and worked in Somerset, Suffolk,
and Norfolk until 1884, when he removed to Reading and was for
any years occupied on the re-survey of that neighbourhood, giving
special attention to the Drifts, which before had only been partially
mapped. He then proceeded to Oxford, where he laboured on,
having nearly completed the MS. of this memoir at the time of his
death, March dth, 1901.
The geology of the Reading area has been rendered classical as
the scene of some of the early labours of Prestwich, the fine sections
of the mottled plastic clays, so long worked as tile-earth, having led
him to adopt the name ‘ Reading Beds’ for the varied group of
strata which here intervene between the Chalk and London Clay.
The district is one in which the action of rivers and changes in
their courses are conspicuously shown, a subject which has been
dealt with by Mr. H. J. Osborne White and others, but requires to
be discussed in reiation to a much wider area than is covered by
this Sheet (No. 268).
Mr. H. W. Monckton, who has devoted much labour for many
years to the elucidation of the Bagshot Beds and the Gravels of
the Thames Valley, has kindly undertaken the task of editing
Mr. J. H. Blake’s MS. for publication, and, whilst retaining all
Mr. Blake’s notes, he has freely inserted additions from his own
notebook, especially in the chapters relating to the superficial
deposits, for which Mr. Monckton may thus be considered to some
extent responsible. The map, it is to be regretted, has not at
present been printed in colours, but two editions, with and without
Drift, were issued in 1898 hand-coloured. We hope the superior
colour-printed map will shortly be obtainable for this district.
The country around Reading embraced in Sheet 268 represents
an area of 216 square miles; that portion on the north of the
Thames being in Oxfordshire, and the remainder in Berkshire, with
the exception of a somewhat irregular narrow strip along the south,
‘which is in Hampshire. Reading, the capital of Berkshire, is
situated near the central part of the area. The area is drained
by the River Thames and its tributaries, the Pang, the Kennet,
and the Loddon, together with minor streams.
The following is a list of the geological formations which are
shown on the map by distinctive colours :—
Alluyium.
RECENT .. se {tutn
Loam.
Valley-gravel.
PLEISTOCENE ..._ ...4 Clay-with-flints and loam (overlying the Chalk).
Plateau-gravel.
Pebble-gravel.
318 Reviews—Geological Survey of England—Reading.
Bracklesham Beds.
Lower Bagshot Beds.
London Clay.
Reading Beds.
r .
CRETACEOUS ... ... { eee
Only the Middle and Upper Chalk come to the surface in this
district, but at Winkfield, in Windsor Forest, a boring passed through
the whole formation, and the thickness was found to be 725 feet,
of which 219 feet was Lower Chalk, 169 feet Middle Chalk, and
3387 feet Upper Chalk.
The Chalk exists throughout the district, but is only found at the
surface over a comparatively small part, for, in the southern half of
the area and in parts of the northern half, it is covered by Hocene
strata often of great thickness, and in other parts the Chalk is hidden
under beds of Drift.
The Middle Chalk is divided into two zones, namely :—
2. The zone of Terebratulina (gracilis ? var. lata, Eth.).
1. The zone of Rhynchonella Cuviert, D’Orb.
The zone of Terebratulina consists of smooth white Chalk, and in
it nodules of flint are occasionally found. It has been termed the
zone of Terebratulina gracilis, but it is now known, through the
researches of Dr. F. L. Kitchin, that this species does not occur
below the uppermost division of the English Chalk. The name to
be used for the species of Terebratulina in the Middle Chalk has
yet to be decided; it has been called T. gracilis, var. lata, by
My. Etheridge.
The Middle Chalk runs down the Thames Valley from Goring
and Streatley by Basildon to Pangbourne. Details of the several
exposures of this division are given on p. 8 by Mr. Jukes-Browne.
The Upper Chalk consists of soft white Chalk, more or less evenly
bedded, with numerous irregular nodules of flint along the planes of
bedding, and sometimes in the Chalk itself between the planes.
Thin seams of tabular flint occasionally occur along the bedding-
planes, or fill fissures or joints inclined at various angles to them.
At its base is the Chalk Rock, a cream-coloured limestone with
glauconitic grains and many green-coated nodules.
The Upper Chalk is divided into several zones, only the three
lower of which have been identified in the Reading district, namely :
3. The zone of Micraster coranguinum, Leske.
2. The zone of Micraster cortestudinarium, Goldf.
1. The zone of Holaster planus, Mant.
(1) The zone of Holaster planus includes the Chalk Rock, which,
as has been said, forms the base of the Upper Chalk. The average
thickness of this zone in the Thames Valley is about 20 feet. Several
localities and sections are recorded, e.g., an old quarry facing the
Thames in Harts Lock Wood opposite Basildon, and in the road-
cutting on White Hill, east of Goring.
(2) The zone of Micraster cortestudinarium, Goldf. The average
thickness of this zone in the Thames Valley is about 60 feet, and
Upper Bagshot Beds.
Eocene ... 4
Reviews—Greological Survey of England—Reading. 319
there seems to be some thickness of Chalk exposed in several pits
which is referable to it. Part of the zone is well exposed in the
railway cutting west of Pangbourne, where the beds are bent up
into a slight anticlinal curve, of which a sketch is given.
(3) The zone of Micraster coranguinum, Leske. Along the
valley of the Thames the thickness of this zone is about 200 feet.
Exposures in quarries are numerous from Whitchurch to Shiplake,
and probably all belong to the same zone.
At Mapledurham and Chazey Farm, at Caversham, and south-east of
Wargrave in Berkshire, similar exposures of this zone can be seen.
Chalk is exposed in most of the valleys in the north-western part of
the area, and the fields are in many places thickly covered with
flints.
Reading Beds.—There is a great break in time between the Chalk
and the Reading Beds, which are here found resting upon it; for not
only are the highest beds of the Chalk wanting in this area, but
a considerable series of Hocene strata which in other places is
found below the Reading Beds is also absent. 'The Reading Beds
accordingly here lie upon a greatly but evenly eroded surface of
the Chalk.
The whole formation in this area varies from about 70 feet or less
to 90 feet in thickness, and is composed of variously coloured
mottled plastic clays and more or less loose sands; the clays are
the upper part, and vary from 30 to 50 feet in thickness, the sands
forming the lower part, being from 20 to 40 feet thick. The