The Publisher will mail this Journal to any Address in the United States, for one year, on receipt of Post Office Order for 11s. NO. 17. Series. Jan. 1881. [2s. 6 THE POPULAR ricttcc 1 m mt EDITED BY W. S. DALLAS, F.L.S. Assistant-Secretary of the Geological Society. CONTENTS. The Planet Jupiter in October and November, 1880. By W. F. Denning, F.R.A.S. (Illustrated.) The Anatomy of the Stag Beetle. By A. Hammond, F.L.S. (Illustrated.) Oil Fog. By W. H. Stone, M.B. Some Facts about Fishes. B3’ the Editor REVIEWS. The GJvall nger's Voyage — Elements of Astronomy — Geometry — Belfast Lough — North American Seals — Infusoria — The Atomic Theory — Memoir of a Young Chemist — A simple book on Heat — Elementary Chemistry — Tables for Analysis — The Gardens of the Sun — The Poetry of Astronomy. SCIENTIFIC SUMMARY. Astronomy — Botany — Chemistry — Geology and Pakeontology — Mineralogy — Physics — Zoology. ILLUSTRATED. LONDON : DAVID BOGUE, 3 ST. MARTIN’S PLACE, TRAFALGAR SQUARE. 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Complete in parts . . price 7 12 6 Or in 15 volumes, in cloth . „ 9 2 0 Or in half-morocco . . „ 11 8 0 CONTENTS OF VOL. V. The Planet Jupiter in October and November, 1880. By W. F. Denning, F.R. A.S. (Illustrated) The Anatomy of the Stag Beetle. By A. Hammond, F.L.S. (Illustrated) On Fog. By W. H. Stone, M.B Some Facts about Fishes. By the Editor The Myxomycetes or Mycetozoa ; Animals or Plants ? By W. Saville Kent, F.L.S., F.Z.S., F.R.M.S. (Illustrated) The Permanence of Continents. By J. Starkie Gardiner, F.G.S. Preliminary Note on the Existence of Ice and other Bodies in the Solid State at Temperatures far above thf.ir ordinary Melting Points. By Thomas Carnelley, D.Sc., Pro- fessor of Chemistry in Firth College, Sheffield (Illustrated) On the Former Existence of the Roe-Deer in England. By J. E. Harting, F.L.S., F.Z.S Contributions to the Knowledge of the Hottentot Race. By M. J. A. Roonda Smit The Movements of Plants. By the Rev. George Hens low, M.A., F.L.S., F.G.S. (Illustrated) The Centenary of the Discovery of Uranus. By W. F. Denning, F.R.A.S. (Illustrated) The Eye-like Spots in Fishes. By Professor H. Jeffrey Bell, M.A. (Illustrated) The Blackheatii Subsidences. By T. Y. Holmes Scientific Teaching. By AV. Stone, M.B., F.R.C.P. The Classification of the Eozoic and Lower Palaeozoic Rocks of the British Isles. By Henry Hicks, M.D. (Illustrated) ... On the Colours of Spring Flowers. By Alfred W. Bennett, INI. A. On the Retreat of the European Glaciers. By Prof. C. Du four PAGE 1 14 27 40 97 117 128 136 147 193 207 221 235 248 289 309 IV CONTENTS. PAGE The Storage of Electricity. By J. Munro, C.E. (Illustrated) . . . 320 On the Formation of the Tails of Comets. By M. Faye ... 327 Atyoida Potimirim, a Mud-Eating Fresh-Water Prawn. By Dr. Fritz Miiller 330 The Mode of Action of Facetted Eyes. By Prof. Si°*mund Exner ... Reviews of Books Scientific Summary : — Anthropology Astronomy Botany ... Chemistry Geology and Palaeontology Mineralogy Physics ... Zoology ... 337 50, 160, 257, 346 172 68, 173,358 ... ... 71,178, 362 78, 271, 364 82, 178, 272, 365 85, 279, 367 87, 183, 280, 369 92, 188, 287, 370 379 Index Pop. Sci. Pazv. N. S. VolV. PL 1. t ...... Mintem Hro's . imp. •JUPITER & SATURN, in 1880. OCT & NOV. POPULAR SCIENCE REVIEW. THE PLANET JUPITER IN OCTOBER AND NOVEMBER, 1880. By W. F. DENNING, F.R.A.S. [Plate I.] FROM remote ages, long before the period when the Chal- daean shepherds began something like a systematic survey of the heavens, the brightness and conspicuous aspect of the Jovian planet has continued to attract the attention and admira- tion of mankind. Whilst the Chaldaeans introduced their nomenclature of the constellations, and placed a variety of figures and forms in the sky to inaptly represent the curious groupings of the stars, this planet must have been the brilliant spectator of the work. Belonging, as he did, to the class of ‘ wandering stars/ it was impossible to limit him to any definite region of the sky, and to give him an enduring place amongst the variety of imaginative titles which were then affixed to the stars. Shining with surpassing lustre, and with a unique steadiness in remarkable contrast to the scintillations of the stellar orbs, we need not wonder that many inquiring glances were directed to him, and many speculations hazarded as to his physical aspect, and the special purpose he was designed to fulfil in the scheme of creation. At that day men were all uncon- scious of the marvellous system which, in after times, the tele- scope revealed. They could have little conception of the wonders which delighted the eye of Galileo in January 1610, when he first beheld the Medicean stars, as he called the four satellites, and watched their revolutions as they upheld the Copernican system of the Universe, and unfolded a host of new facts to his gratified understanding. Since Galileo’s time nearly three centuries have rolled away. Astronomical science has marched onwards with a rapid pace, ever accumulating fresh knowledge and perfecting its appliances of research. The puny, incompetent telescopes of former times have been supplanted by the giant instruments of Ilerschel, Rosse, Lassell, and others, which have been employed to search NEW SERIES, VOL. V. NO. XVII. B 2 POPULAR SCIENCE REVIEW. out new items of discovery, and to bring to light new orbs from abnost fathomless space. The Jovian planet has always been the subject of special attention. His system of attendant moons, and the singular belts of shading which diversify his globe, have been observed again and again; and one of the most important facts gleaned from such observations was that of the extreme swiftness with which objects were carried across his surface, and the resulting inference that the length of his day was very much shorter than ours. Cassini had, as early as 1665, determined the period as 9h 56m, and this conformed with remarkable precision with determinations of more recent date by Maraldi,W. Herschel, Schroter, Madler, and others, who gave slightly differing values, averaging 9h 55Jm. The method of proceeding in each case was to observe certain dark spots as they were successively presented on the same points of the planet’s surface, when, by noting the exact intervals which elapsed between their reappearances, the period of rotation became readily ascertainable. The slight discordances apparent in the values independently assigned by the several observers could be explained on ordinary grounds. The spots may not in all cases have been subject to the same conditions. Some of them may have exhibited proper motion, which must have clearly originated such discrepancies. In the summer of 1878 a dark elliptical spot of considerable dimensions and very striking character made its appearance on the surface of Jupiter. It was situated just south of the great equatorial belt of the planet, and it still remains visible, forming a most frequent and interesting object for telescopic examina- tion. It displays the same intensely red colour as the adjoining dark belts, and appears likely, from the constancy of form and distinctness of outline which it invariably exhibits, to remain perceptible for a lengthened period. No one can possibly foresee the date of its final disruption and disappearance, because we are ignorant of the conditions under which it exists, and of the influences to which it is subject. Of its origin we also know little or nothing. It was already a conspicuous object, display- ing an intense rosy hue, when first discovered by Prof. Pritchett at Missouri on July 9, 1878. In fact, the spot does not appear to have been traced in the early stages of its formation, so that it cannot be said the process was gradual, and that the object, first becoming visible as a minute speck, went on enlarging and intensifying until it reached its present striking proportions. The spot may quite possibly have resulted from a sudden convulsion in the Jovian atmosphere, by which a large area was sundered, and the planet’s dark surface in part revealed. In any case, the seemingly permanent character of the spot and its well-marked outline are its most salient features ; and should indications THE PLANET JUPITER IN OCT. AND NOV. 1880. 3 either of decay or further development be presented, they will be quickly noticed by the host of observers who are engaged in watching what is certainly one of the most singular and attrac- tive of the astronomical phenomena of our time. Some important purposes will be served by the long endu- rance of this unique object. It will give us the means of computing, with greater facility and accuracy than was ever attempted before, the period of rotation of Jupiter. This has been already attempted with some success, and the resulting values in two instances are 9h 55m 34s2 and 9h 55m 33s,9. These were derived from observations during the opposition of 1879, and they show that the period of 9h 55m 26s, which has been commonly adopted hitherto, is fully 8 seconds short of the true interval. But though the new determination of 9h 55m 34s above referred to may be relied on as extremely exact, it should be suggested that the work has been undertaken prematurely. It is advisable not to be too sanguine of results depending on short periods, however carefully the details have been worked out. The final discussion of the question must be left to a future time, for it will be obviously preferable to rely on a period extending over several years than on a period extending over a few months only. The planet, as observed on two dates, say four months apart, has performed less than 300 rotations, whereas, if the interval is extended to four years, the number of rotations will be more than 3500 ; and seeing that the large spot now visible is likely to endure for a period at least equal to this, we can well postpone the ultimate analysis to the time immediately preceding the end of its visible existence. We shall then be enabled, by a comparison of a few of our best observa- tions, to deduce the period with more precision than could result from a mere partial investigation. But just as astronomers had been congratulating themselves upon such excellent means of finding the length of the J ovian day, we had the announcement that the markings upon the disc of the planet are influenced by a variety of different motions. The great red spot, which has created so much stir amongst ob- servers of planetary phenomena, cannot keep pace with the white spots which alternate with the darker areas around the shaded equatorial girdle of the planet, nor do the black spots of smaller type (some varieties of which have lately been spread along a faint belt in the north hemisphere) maintain permanent positions, either with respect to each other, or to the other markings on the surface. In fact, as observed on different nights, the appearance of the planet is vastly altered ; a series of rapid currents, probably atmospheric, has displaced the relative positions of the chief obj ects. While the great red spot in the southern hemisphere makes its regular apparitions at 4 TOPULAR SCIENCE REVIEW. periods of 9h 55m 34s, the white equatorial spots are only 9h 50^m, and the black spots in the north hemisphere only 9h 48m. The smaller spots have, therefore, a swift proper motion from west to east around the planet, and they have been seen, on several consecutive nights of observation, to overtake the red spot, to pass rapidly by it, and then to precede it by a distance increasing with every successive epoch. These facts are thoroughly well authenticated by the accordant results of several diligent observers. That phenomena of such striking aspect and indicative of stupendous changes in the atmospheric envelope of the planet should have so long escaped the frequent and vigilant scrutiny its importance greatly demanded, is very surprising when we consider the host of adequately powerful telescopes which are again and again directed to Jupiter at each recurring opposition. For there is no sufficient reason to think that the curious details recently observed are of very rare character, and special to our own time. Notwithstanding their present very distinct and palpable occurrence, we have every right to assume that they are the simple evidence of what is constantly manifested in the physical aspect of the planet. Look at him whenever we will, we shall find some indications of vast disturbances, and (though there may be times of comparative quiescence in such phenomena) they will occasionally he so conspicuous as to call for particular comment. But the more minute of these appear to have eluded observers in past years, and it is only now that the apparition of the great red spot has so fully aroused interest that they seem likely to receive a full investigation. We shall certainly learn something of the singular phenomena occurring on the planet by their means. The complexity of spot-motion which the observations are unfolding, have their explanation ; and this may be forthcoming when the results come to be collated and compared in the final analysis. We have said that former observers had overlooked these important facts. We mean by this that the matter had never been discussed with any thoroughness, and that, though we may find amongst old records some brief, vague references to pheno- mena similar to those which are now engaging so much notice, they never received a due meed of attention. We can go back, indeed, more than two centuries, and trace what may have been a precisely similar observation to what is now recorded. Cassini, in 1665, determined the rotation period of Jupiter as 9h 56m ; and seven years later, from other spots which he distinguished, at 9h 55m 50s. These results, so nearly coincident, were evidently derived from markings of analogous character to each other, and to the red spot which is at present visible on the planet. Twenty years later, namely in 1692, Cassini observed another THE PLANET JUPITER IN OCT. AND NOV. 1880. 5 spot, whose motions he watched with the same assiduity as in the preceding instances, and deduced a period of 9h 50m from his new observations. The inference is obvious. He had observed objects of different nature, showing a difference of motions, for the discordance of nearly six minutes between his values cannot possibly he accounted for on other grounds. The trivial discrepancy of 10 seconds between his first two values is readily explained by errors of observation ; but the large dis- agreement with his subsequent calculations is only to he satisfied on the assumption that the spot exhibited proper motion. Schroter has also left on record an observation of black spots crossing the Jovian disc in abnormal periods; and Madler, in his Popular e Astronomie has a reference to similar phenomena. In September, 1880, the writer commenced a series of obser- vations of Jupiter, with the object of noting the peculiar forms of the markings, and of generally recording such changes as might be presented in his appearance. The telescope em- ployed was a reflector of 10 inches aperture, by Browning of London. The powers used depended upon the state of the atmosphere. Sometimes the performance of the instrument was best with 300, but under ordinary circumstances 450 was the most effectual ; and at times, when the air was very steady and the planet free from that tremulous movement so annoying to observers, 500, and even 600, could be used with advantage. The usual appearance of the planet was that of a globe striped with a variety of dark parallel bands. Whenever the large spot was visible, the aspect was different. Its well- defined outline and the contrast it offered to the series of con- tinuous belts, gave a special character to the view (PI. I. fig. 1). In the equatorial region of the planet, there was always a very broad and variously marked zone of shading. A mass of detail was apparent here, and changes of great extent were evidently in progress. The zone was bounded, on both its north and south limits, by a dark streak, that on the north side being obviously the deeper of the two. Included within these streaks, there were fainter patches interspersed with lighter areas and spots. The latter were usually slightly on the southern side of the equator, while, immediately on the other side and contiguous to the north streak, though distinct from it, was an irregular row of dusky patches. In the southern hemisphere, the great spot was visible adjacent to the great belt (see Fig. 1), and preceding this to the southward, there lay a smaller elliptical spot, which was discovered by Mr. Barnard, at Nashville, Tennessee, on July 24th, 1880. Several faint belts were perceptible on the south side of these objects, and the south pole itself was capped by a dusky shadowing, or by a numerous array of belts so close together as to be inseparable. In the northern hemisphere, 6 POPULAR SCIENCE REVIEW. more belts were generally distinguishable than in tbe southern ; and one of these, outlying the great equatorial zone, was always very plain and conspicuous. After the middle of October it became indeed an object of considerable interest, for it exhibited a series of dark spots and patches, which developed so rapidly and moved with such celerity as to give the most distinct evi- dence of phenomena of marvellous character. The first signs of the disturbance appear to have been noticed by Mr. Dennett, at Southampton, at midnight on October 17th, when two dark spots were seen just past the central meridian of Jupiter , and in north latitude about 25°. These soon became much more conspicuous, others formed and they spread out to such an extent that at the present time they extend fully half-way round the planet, though at the time of their discovery they were separated by an interval not exceeding some 20° of longitude. The writer first noticed the disturbed state of the belt on the night of October 24th, at 11 J p.m., when a train of dark spots was visible on the west limb (see PI. I. fig. 2). They were detected again on October 29th and subsequent nights, and the individual spots of the group were recorded as they crossed the central meridian of the planet. To show how quickly the spots extended them- selves along the belt, let us compare the periods occupied by the whole group in passing the meridian : — Oct. 29 . h m 0 53 Deg. of Long. 32-0 Nov. 2 1 27 52-6 Nov. 8 . 1 50 66*5 Nov. 23 3 19 120*3 Nov. 27 . 4 21 157-8 These spots soon gave indications of proper motion. Their period of rotation was about 7J minutes less than that of the great red spot, — in fact, between October 29th and December 2nd, a comparison of their positions shows them to have made a com- plete circuit of the planet ! They had only occupied 34 days in traversing the vast extent of the Jovian sphere. A further development of the spots in the same longitudinal direction will soon have the effect of entwining them completely around the planet ; and such appears to be the inevitable result of their recent behaviour. We may then expect to see their gradual disappearance as distinct spots, though they may possibly be perceptible for a long time afterwards under the character of a very conspicuous belt lying north of the equator. If this eventually proves to be the case, and the future appearances of the spots should be critically watched to ascertain whether it is so, we shall have a good instance as to how these large belts are formed. The inference will be that they are originated by an THE PLANET JUPITER IN OCT. AND NOV. 1880. 7 uprush, or emission, from the planet’s surface ; and that as this reaches the outer regions of the atmosphere it is dispersed in the direction of the longitude by the effects of the rapid rotatory motion of the planet. It is certain that these small spots are different in some essential details from the large spot in the southern hemisphere, inasmuch as they display a very erratic form of appearance and rate of motion, and are probably to be accounted for in a totally different manner. On the other hand, the minute elliptical spot, south preceding the red spot, has, by its constancy of position, sufficiently proved itself to be of analogous character. We have mentioned light patches and spots as discernible in the southern interior border of the great equatorial belt, and there is one of these which should be singled out as displaying a more prominent aspect than any of the others. It was first seen by the writer just before midnight on September 18th, when the following reference was entered in his note-book : — ‘ 1880. September 18th, llh 50m, observed Jupiter with 10-inch reflector, power 150 ; but there were storms and clouds which interrupted, though the planet was fairly well defined at times. I noticed a bright spot' directly, about half way across the disc and just south of the equator. Another bright, ellip- tical spot preceded this, and indeed on the equatorial borders of the great southern belt the surface was very bright in places, giving the impression of more objects of similar kind. The chief spot had a pearly whiteness and stood out with con- spicuous plainness amongst the mass of detail faintly traceable along the planet’s equator.’ I took particular care to re-observe this curious appearance as often as possible during the ensuing months of October and November, and to note, with as much accuracy as eye- estimates permitted, the exact times when it crossed the central meridian of Jupiter. The following results were thus obtained : — Sept. 18 h m . 11 50 ... Long. 85°8 Nov. 19 h. m . 9 23 ... Long. 339-4 Oct. 20 . 11 38 ... 221-9 Nov. 20 . 5 2 ... 332-a Oct. 30 . 7 28 ... 137-5 Nov. 21 . 10 41 ... 327-8 Nov. 2 . 14 15 ... 115-6 Nov. 26 . 8 44 ... 289-9 Nov. 3 . 9 47 ... 104-2 Nov. 27 . 4 19 ... 280-2 Nov. 4 . 5 25 ... 96-4 Nov. 28 . 9 51 ... 271-4 Nov. 8 . 7 48 ... 65-4 Nov. 29 . 5 27 ... 262-4 Nov. 17 . 8 14 ... 356-7 Dec. 3 . 7 54 ... 233-4 Thus in 76 days the spot had apparently traversed 572° *4 of Jovian longitude, which is equivalent to 7 0-5 per day. This is with reference to the assumed position of the first meridian, 8 POPULAR SCIENCE REVIEW. which is based on a period of 9h 55m 27s*08, derived from the observations of dark spots seen in 1834-5 and 1862. But if the motion of the white spot is taken relatively to that of the red spot now visible, which rotates more slowly than those of 1834-5 and 1862, referred to, it becomes even greater ; for during the eleven weeks over which the observations extend, the aggregate movement will be 586°, or 7° 7 daily = nearly 13 minutes of time. This motion has not been uniformly maintained. The records show a considerable retardation during the latter period of the observations. Let us divide the dates into nearly equal intervals and compare the calculated periods from each of them : — h m Observed period, h m s Oct. 20 . Oct. 30 . . 11 38 { 7 28 1 • 24 rotations 9 49 35 Oct. 30 . Nov. 8 . 7 28 7 48! | 22 rotations 9 50 0 Nov. 8 . Nov. 17 . 7 48 ] 8 14! j- 22 rotations 9 50 16 Nov. 17 . Nov. 26 . 8 14 j 8 44! | 22 rotations 9 50 27 Between November 26th and December 3rd, the motion seems to have been accelerated, the period being 9h 50m, exactly, and similar to that of the period from October 30th to November 8th. Certain trivial, though important, corrections have to be applied to these times. Differences in the longitudes of Jupiter and the Earth, and in the varying distance and phase of the planet have severally to he computed and the resulting values applied to the simple observed periods. But the corrections required are very small, not exceeding a few seconds, and will be properly discussed when the observations have reached a more complete stage and are in process of final reduction. In Fig. 3 (PI. I.), I have endeavoured to show the appearance of the white spot in the equatorial belt on November 28th, when it was noted as central on Jupiter. Compared with the dark rifts and streaks in its vicinity, the spot is strikingly prominent, lying a little south of the equator and breaking into the great south belt. In Fig. 4 are shown its several positions as it over- took the red spot on the nights of November 17th, 19th, 20th, and 21st. On November 19th, the white spot appeared to he situated in precisely the same longitude as the red spot. On the following night its swifter motion had carried it forward considerably in advance of the middle of the red spot, and on November 21st it was perceptible under the preceding end. The following is the comparison of the observed times of transit of THE PLANET JUPITER IN OCT. AND NOV. 1880. 9 these spots and the differences which their discordant motions have originated : — - Date. Red spot. White spot. Difference. Nov. 2 h m 10 26 h m 14 15 + h m 3 49 Nov. 3 6 12 9 47 + 3 35 Nov. 8 5 21 7 48 + 2 27 Nov. 17 7 44 8 14 + 0 30 Nov. 19 9 23 9 23 + 0 0 Nov. 20 5 14 5 2 — 0 12 Nov. 21 11 4 10 41 — 0 23 Nov. 27 6 0 4 19 — 1 41 Nov. 28 11 49 9 51 — 1 58 Nov. 29 7 40 5 27 — 2 13 Thus, on November 2nd, the white spot followed the red by 3h 49 m, but, gradually drawing up to it, the interval decreased until November 19th, when the two objects mutually inter- sected the meridian at 9h 23m. After this the white spot pre- ceded by a distance rapidly accumulating, so that when I last observed both the spots, on November 29th, the interval separating them had become 2h 13m ; the daily excess of velo- city of the white spot compared with the red had been 13-J- minutes for the period included in the dates November 2-29, and slightly more than that (13 minutes), deduced from the whole series of observations from September 18th to December 3rd, referred to above. It should be mentioned that in the sketches the objects are in each case represented as seen in an inverting telescope, so that the planet’s east limb appears on the right-hand side, and the northern hemisphere is the lower hemisphere as depicted in the figures. It is satisfactory to know that the singular white spot has been observed pretty frequently, and that it will be carefully watched as it successively becomes favourably presented on the disc of Jupiter. It is undoubtedly liable to great variations of brightness, and the light spots in its close neighbourhood have been noticed several times to alternately appear and disappear at remarkably short intervals. Indeed the effect produced has been something similar to that of dark clouds sweeping over brightly luminous regions ; and the mere fact of recurrence of identical markings on the Jovian disc, leads to the inference that such phenomena are referable to atmospheric origin. It is impossible to conceive that such immense changes can occur on the real surface of the planet. They must be attributable to a rapidly variable envelope, influenced by swift currents and opposing forces, so that its density and thickness become thereby affected and the sunlight reflected in different degree. 10 POPULAR SCIENCE REVIEW. Large openings may result, so that the lower strata become ex- posed, or even the actual surface of the planet itself rendered visible through the fissures. It would be strong evidence in support of the latter thesis should the fact of recurrent bright markings be fulty established by further observations ; for it will be impossible to explain them on other grounds than that they are physically connected with the planet. Temporary obscurations will be accounted for by atmospheric inter- ferences. The phenomena of the dark and red spots in regions of the north and south hemispheres may also possibly receive a similar explanation, though we require a mass of well- authenti- cated records before the solution of the question can be satis- factorily brought about. A series of reliable drawings re- presenting the telescopic features of the planet at each ensuing opposition would, if extending over many years and executed by the same hand and instrument, be extremely valuable in such an investigation. A systematic scrutiny of the planet might be undertaken by a band of observers acting in unison, and the results accruing each year carefully registered for future comparison. Markings, if recurrent, would then be revealed in time, and their periods ascertained. It is true that drawings by different observers often show much dissimilarity ; but this should not, in the case where a large number are avail- able for comparison, have an unfavourable effect upon the dis- cussion, because the different styles of depicting details must soon become apparent and might be allowed for throughout the series. Thus the sketches would become readily comparable, and admit of such mutual corroborative testimony as the subject allowed. Observers engaged in a work of this kind must, however, exercise extreme caution in representing the details just as they see them, and not allow their imaginations to influence them in the slightest degree. On bad nights, when definition is execrable and the interesting features of the planet blotted out, nothing should be attempted. It will be better to wait for more favourable conditions of atmosphere than to make an effort to reproduce what can, at the- best, be very uncertainly seen, and what may prove an ultimate source of discordance and error. The diminutive pictures of Jupiter which we are accustomed to see in popular works on Astronomy and in scientific serials, should give way to sketches of larger dimensions. It is impos- sible that the details can be suitably and adequately repre- sented in drawings obviously too small for the purpose for which they are designed. It is true there is considerable diffi- culty in depicting this planet with all the details visible at a certain time ; his swift axial rotation originates a rapid change THE PLANET JUPITER IN OCT. AND NOV. 1880. 11 in their apparent positions, and it is manifestly impossible to combine tbe observations of several nights because tbe objects bave in tbe meantime undergone a great displacement in their relative places. Let any observer execute a careful sketch of tbe planet when tbe red spot is on the central meridian, and then, three or four nights later, make a similar drawing. He will, on comparing them, find they are utterly incompatible. Tbe objects which in bis first sketch were immediately adjacent to tbe red spot, are seen considerably in advance of it (towards tbe western limb), while others, which in bis previous observa- tions were between tbe centre and east limb are now lying directly under tbe red spot. Such facts bave to be carefully considered by observers of Jovian phenomena, hence their sketches are necessarily hurried and often imperfect in de- tails. We bave been particular in describing these observations of spots on Jupiter , because tbe phenomena so distinctly exhibited by them must obviously command tbe attention of every one interested in inquiries connected with tbe physical condition of tbe Jovian planet. Tbe singular diversity of appearance and motions which bave been pointed out, must be eagerly traced in their future sustenance and development ; and it is of happy augury, as indicating tbe interest centred in tbe subject and tbe probability of its successful investigation, that so many ob- servers are now devoting a share of their time to tbe work. Tbe acquisition of numerous records that must accrue from many independent sources will possess considerable value, and be tbe means of eliminating such errors as are unavoidable in observations of meagre character. Mr. Dennett at Southampton, Mr. Williams at Brighton, and tbe writer at Bristol, simultaneously pointed out tbe evi- dences of rapid proper motions in tbe dark spots recently ob- served ranged along a belt in tbe northern hemisphere of Jupiter. Tbe white spot just south of tbe planet’s equator was detected by tbe writer on September 18, and it came under general obser- vation after November 17. Mr. H. Corder at Chelmsford has re-examined it on many occasions, and noted its transits across tbe central meridian of Jupiter. He bad been previously led to infer tbe motion of tbe ‘ white ovals ’ on tbe equator from ob- servations with a 4J-inch reflector in tbe autumn of 1879, and bad given a summary of bis observations in tbe Observatory for December of that year. From certain changes of position which be remarked on succeeding nights, be concluded that, relatively to tbe red spot, they completed a circuit of tbe planet in about forty days. In conducting bis recent observations, tbe writer has not paid special regard to tbe appearances of tbe satellites. Their 12 POPULAR SCIENCE REVIEW. shadows have been several times noted crossing the disc as black spots of very distinct aspect, and Satellite I. has been seen, both by Mr. Corder and the writer, projected on the disc as a dusky spot. These 4 dark transits ' of the first satellite are somewhat rare, though it would appear that during the present opposition they have quite lost their exceptional character. The large extent of detail manifested on the surface of Jupiter has often impressed the writer with the necessity of a critical and searching review. There is a wide field here for patient labour and painstaking scrutiny. We have often heard of the vast amount of scenery on the lunar surface, and of the magnitude of the task involved in its complete delineation ; and we have been told by those who have laboured in the field of meteoric astronomy, of the multitude and variety of the meteor streams which the Earth annually intersects. Indeed, each of us has learnt, in his own department, to realize something of the stupendous nature of the subject to which our individual energies have been applied, and to admit that we can never hope to attain more than a very partial knowledge at the best. In the scenery of Jupiter and its swiftly- varying aspects, we may find another large field for exploration, holding out as rich a prospect of successful results as that of any other branch of astronomical research. Those who, during the last few months, have been engaged in examinations of Jupiter will frequently have turned their telescopes upon Saturn , situated not far to the eastward, and viewed his wonderful ringed sphere. It is true that this planet scarcely affords, from his greater distance, the same extent of detail as that perceptible upon the disc of Jupiter ; but the appearance of the ring amply compensates for whatever is wanting in other respects : and there is this to be said, that Saturn is commonly much better defined in a telescope than Jupiter. The brightness and glare attending the latter planet brings about an indistinctness which only the best conditions of atmosphere can fully eliminate ; while, in the case of Saturn , the moderation of lustre has the obvious effect of inducing the best performance of the telescope. This planet has lately been frequently subjected to careful inspection by the writer, and such features as could be discerned with certainty were noted down. The ring showed two divisions — one as a plain, black, curving streak, the other as an extremely faint line, not far from the outer extremity. The inner dusky (or crape) ring was also seen, and the exterior border of the outer bright ring seemed very dark, and where it was projected upon the planet, was visible as a dusky bar of shading, giving the impression that there is another dark ring lying closely outside the system of bright THE PLANET JUPITER IN OCT. AND NOV. 1880. 13 rings. Upon the planet himself a series of belts were always observed, though sometimes with greater distinctness than at others ; but, compared with the belts on Jupiter , they were remarkably faint, wholly lacking that decided character and variegated aspect invariably shown by the latter phenomena. Near the south pole of Saturn there was a very dark cap, and separating this from the belts lying near the equator, there intervened a lighter zone. Bright patches were suspected on this, particularly where it came up to the planet’s margin ; and on November 17 a marking of this nature was certainly seen on the south- south-west limb, though it remained in view only for a short interval, and could not be reobserved on subsequent occa- sions. Some observers have referred to the figure of Saturn as sometimes assuming a singular form known as ‘ square- shoul- dered/ and the fact is supported on unequivocal testimony. The writer had not made many observations before this curious figure became distinctly apparent, causing an evident distor- tion of the globe, and a departure from the true spheroidal form. Attention was then more specially directed to the cir- cumstances, and the explanation appeared to be that, while the bright belt above alluded to had the effect of apparently e raising’ the globe, the dark bands compressed it to such a degree as to bring about a very palpable deviation from the normal form. This is a fact which future observers should consider. In addition to the bright belt referred to, the system of Saturn exhibited two other markedly bright zones — one on the planet’s equator, and the other lying immediately within the major division in the rings. EXPLANATION OF PLATE I. Fig. 1. Jupiter , his belts and great red spot. 1880, October 14th, 9h 35m. Fig. 2. Jupiter and his belts. 1880, October 24th, llh 15m. Fig. 3. Section of the great equatorial belt, showing the white spot. 1880, November 28th, 9h 51m. Fig. 4. The white spot overtaking and passing the red spot, as observed on November 17th, 19th, 20th, and 21st. The apparent motion is from east to west, i.e. from right to left in the diagram. Fig. 5. Saturn and his rings. 1880, November 28th, 8h 30m. 14 THE ANATOMY OF THE STAG BEETLE. By A. HAMMOND, F.L.S. [Plate H.] INSECTS are Articulated Animals, in which the integument plays the part of the internal skeleton of Vertebrates, forming surfaces for the attachment and play of muscles, as well as a covering and protection for the vital organs they enclose, for which purposes it is hardened by the deposition of a homy substance called chitine. In their simplest form, that of the maggot or caterpillar, insects much resemble worms, all the rings of the body being nearly similar to each other. In their perfect condition, however, the body exhibits three well-marked divisions, viz. the head, the thorax, and the abdomen, the two former of which hear articulated appendages. An alimentary canal traverses the body, and presents an oesophagus, crop, gizzard, ventriculus, or chyle stomach, and intestine. A chain of double nerve- ganglia runs, united by cords, along the ventral surface of the body, and is connected with the cerebral ganglia, or brain, by cord-s surrounding the oesophagus. Opposed to this is an elongated contractile organ, the dorsal vessel, the chief agent of the circulation. Respiration is effected by means of tracheae, or breathing tubes, opening on the surfaces of the body by special apertures called spiracles.* The mouth-organs are modified limbs, and may be either manducatory or haustellate. They consist of a pair of mandibles, a pair of maxillae carrying palpi, and the parts forming the labium, or lower lip, viz. the mentum, the ligula, and a pair of labial palpi ; a horny plate called the labrum covers the mouth from above. Such is a rough outline of structures which it is intended to illustrate more fully in the insect which gives its title to this paper. Before, how- * The relative position of the alimentary, nervous, and respiratory systems, together with those of the different plates and appendages of the insect crust, are well shown in a figure from Packard. See PI. II. fig. 9. Pop.Sci, Rev NS.Vcl.V.PlP. Fig. 3. rig.Z ep?s' A . Hammond del et, litli ANATOMY OF THE STAG BEETLE Fig. 5 THE ANATOMY OF THE STAG BEETLE. 15 ever, entering in detail on our subject, it will be well to call to mind the principles which determine not only the rank of insects in the Articulate series, but that also of the different orders of insects among themselves ; so shall we be able to view the structures presented to our notice, not as a piece of isolated animal mechanism, but as one holding its special place among others closely allied to it — an example not only of insect structure in general, but of coleopterous structure in particular. The Articulate type, under which Cuvier ranged all those animals whose bodies are composed of a number of successive rings or segments, includes the three great divisions of the Worms, Crustaceans, and Insects ; and these take rank among themselves in proportion to the amount of specialization of function ex- hibited in their organization. This principle has been aptly termed by Milne Edwards as that of the physiological division of labour. The various actions and processes of life termed functions may be carried on, as in that simplest of all animals •the Amoeba, indifferently by any part of the body, or each function may have a special part of the body allotted to it ; and in proportion as this is the case the various functions will be carried on with greater or less perfection. More especially is this seen with respect to the two great functions of animal life, viz. locomotion and sensation as opposed to the purely vegetative ones of nutrition and reproduction. It is the perfection of these functions which places so broad a stamp of superiority on the higher Articulate classes, viz. the Crustacea and Insects, as com- pared with their humbler brethren the Worms. The result of this specialization of function, as exhibited in the body of an articulate animal, is chiefly its more and more perfect differentiation into the three regions of head, thorax, and abdomen ; to the first belong the functions of sensation, to the second those of motion, and to the third the vegetative functions of nutrition and reproduction. The original division of the body into somewhat similar rings becomes subordinate to a new division into regions ; and the more clearly this is observable, the higher rank will the animal exhibiting it take. In intimate connexion with the alterations thus apparent in the external form, there is observable a concentration of the nervous system towards the head and thorax. In its simplest form which obtains in the Worms, this system consists of two longitudinal cords, each with a swelling (nerve-knot, or ganglion), corresponding to each segment. In the Diptera, as an example of one of the higher Insect orders, we find this chain of ganglia reduced to two — one in the head and one in the thorax, — the abdomen being supplied only with filaments from the latter. It is almost needless to point out how this concentration of the nervous system towards the head finds its 16 POPULAR SCIENCE REVIEW. highest expression in the complex brain of man and the Verte- brate animals. The eight principal orders of six-footed insects have been arranged by Packard into the two following groups of Metahola and Heterometabola,* viz. Sub-orders, Packard. Metabola. The body usually cylindrical ; pro thorax ^ small ; mouth parts more generally haustellate Hymenoptera. (formed for sucking) ; metamorphosis complete ; Lepidoptera. pupa inactive ; larva usually cylindrical, very Diptera. unlike the adult. J Heterometabola ; the body usually flattened ; pro-^ Coleoptera. thorax large and squarish ; mouth parts usually | Hemiptera. adapted for biting ; metamorphosis in a large bOrthoptera. number incomplete ; pupa often inactive ; larva I Neuroptera. flattened, often resembling the adult. J Thysanura. In the Metabola, as the higher of these two groups, the differentiation of the thorax from the other parts of the body is more marked than in the other. The three segments of which it is composed, and which are known as the pro-, meso-, and meta-thorax, have coalesced together into a compact mass, separated by deep incisions from the head and abdomen.* * * §)* The function of flight is chiefly concentrated in the mesothorax,* which segment is enormously enlarged at the expense of the other two. In the Heterometabola, on the contrary, the evidences of imperfect specialization are seen in the greater separation of the thoracic segments from each other, and their closer connexion with the abdomen. § The power of flight is not so much confined to one segment, viz. the mesothorax, but is sometimes, as in the Coleoptera, resident in the meta thorax, and sometimes, as in the Orthoptera and Neuroptera, the property of both ; or, again, it may be absent altogether, as in the Thy- sanura. || In conformity with this, the nervous system in the Metabola, as also in the Coleoptera, as the highest order of Heterometabola, exhibits a greater amount of concentration than * It should be observed that these two groups do not form a linear series, but rather two parallel ones. See Packard’s Guide to the Study of Insects , p. 105. t The regional division of the body is more marked than its division into segments. t See figs. 6 and 7 in illustration. § In other words, segmental still prevail over regional distinctions. || In the Hymenoptera and Lepidoptera there are two pairs of wings, but in the former the hind pair are not provided with muscles of flight, and in the Lepidoptera they are imperfectly so, the important longitudinal muscles being absent. I therefore regard them as subordinate to the front pair, and have described the function of flight as chiefly concentrated in the mesothorax. THE ANATOMY OF THE STAG BEETLE. 17 in the other orders ; and the extent of the changes which they undergo in order to reach maturity is in a corresponding degree more marked.* In PL II. figs. 6 and 7, will be found drawings of the Blow- fly and Cockroach, as illustrations of the highest and lowest types of insect structure. In both will be clearly seen the character- istics just alluded to, and in the latter especially the similarity of the thoracic segments to each other and to those of the abdo- men should be noted as evidences of a low grade of develop- ment. The place which the Coleoptera occupy in the scale will be rendered more clear when we describe the thorax, of the/ Stag Beetle. Commencing our description with the mouth-organs, we/ observe that the great horny mandibles, which so conspicuously adorn the head of the insect, are the exclusive property of the male sex, those of the female being small in comparison. They are situated immediately beneath the clypeus and labrum, to be presently mentioned, and are united to the upper and under surface of the head by a hinge-like joint, so as to work back- wards and forwards in a horizontal plane. They are capable of biting with very great force. Notwithstanding the heavy ap- pearance they give to the head of the insect, they are lighter than their bulk would indicate, being quite hollow, and" the cavities occupied only by a cellular mesh containing air, pro- bably a modification of the tracheal vessels distributed to this part. A strong, horny plate is seen between the mandibles on the upper surface, bent downwards, and constituting the labrum or upper lip. PI. II. fig. 1, Ir. This in most insects is articulated to the portion of the head immediately behind it, but in the Stag Beetle the two parts are immovably soldered together. Immediately beneath the labrum and mandibles are found the maxillae, or lesser jaws, PI. II. fig. 15, with which insects are always provided. They are partially concealed by the mentum, beyond which they project as two fringed lobes ; they carry a pair of four- jointed palpi. Their motion, like that of the man- dibles, is in a horizontal plane. In many beetles the office of the maxillae appears to be the retention of the prey within the mouth, and assisting the action of the mandibles. As the Stag Beetle, however, is a vegetable feeder, subsisting upon the juices of trees which it has wounded with its mandibles, these organs are adapted to lap up the juices thus obtained. Beneath these, and closing the mouth from below, are found the parts composing the labium, or lower lip. They consist of a broad, horny plate, the mentum, PI. II. fig. 2, m, immediately * It has been observed that as a rule the degree of perfection of an or- ganism or an organ is the greater the more numerous the grades of develop- ment are which it must traverse to attain its full perfection. NEW SERIES, VOL. V. NO. XVII. C 18 POPULAR SCIENCE REVIEW. within the anterior margin of which is a minute organ divided at its anterior extremity into two lobes, fringed with hairs, PL II. fig. 16, very similar to, though much smaller than, the fringed lobes of the maxillae. These are the paraglossae. They are regarded by some authors as a second pair of maxillae ; and, like them, they bear at their base a pair of minute three- jointed palpi. The upper surface of the head is formed by a large rectan- gular piece, the fore part of which is called the clypeus, PI. II. fig. 1 c, somewhat produced at its anterior angles, where are situate the antennae, consisting of ten joints, the basal one being very long, and the remainder attached thereto at an angle, thus giving an elbowed character to these organs, distinctive of the family Lucanidae, to which the insect belongs. Of the remain- ing joints, the five terminal ones are formed into a pectinated club, somewhat resembling those of the Cockchafer, but not nearly so distinctly lamellated. The function of the antennae is the subject of considerable diversity of opinion amongst naturalists, some believing them to be organs of hearing, some of smell, and others again of a sense unknown to us. A large and conspicuous nerve enters the base of these organs. Em- bryological considerations have led to the conclusion that the four paired organs, viz. the antennae, the mandibles, the maxillae, and the paraglossae, are the limbs of so many segments of which the head is composed. The eyes are of the usual compound type ; they are small in comparison with the size of the insect, probably for the reason that its vegetable-feeding habits do not require its vision to be so keen or so widely extended in range as in carnivorous species. A small process of integu- ment called the canthus extends partly across the eye from its anterior border. This process is extended nearly or even quite across the eye in some of the burrowing Beetles, as in the com- mon Dung Beetle (Geotrupes). The structure of the compound eyes of insects has been so often described that it does not seem to require special comment here. The multiplication of similar parts in the eye of the insect, as compared with the single and highly-finished organ of the Yertebrates, may be taken as an evidence of inferiority of organization. Behind the clypeus, and extending forward laterally as far as the eye, is a piece called the epicranium, PI. II. fig. 1, e ; and on the under surface of the head behind the mentum there are two other portions of the integument, respectively termed the submentum, PL II. fig. 2, sm, and the gula ; but the boundaries of these parts, though clear enough in some insects, are rather difficult to determine in the Stag Beetle. The hinder surface of the head, where it adjoins the prothorax, is perforated by a large orifice, allowing passage for the oesophagus, nervous cord, &c. ; and the portion THE ANATOMY OF THE STAG BEETLE. 19 of integument immediately surrounding this orifice is termed the occiput. The complexity of structure in the head of the insect renders it futile to attempt to discriminate certainly the several seg- ments of which, it is composed from a study of its own structure ; the only light that can be thrown upon it must be derived from an examination of the insect while yet in the egg. It is other- wise, however, with the succeeding portion of the body, the thorax, where, as has been already stated, the segmental division is much more apparent than in the Metabola of Packard, but the regional distinction less so. Hence results the possibility of mistaking at a first glance the large square piece which follows the head for the equivalent of the whole of the thorax, as we see it in the Bee or the Fly, the truth being that this is only the first of the three rings of which the thorax is composed, namely, the prothorax, as is immediately evident by the consideration that it carries only the anterior legs. Hence, also, arises the more intimate union and continuity of the metathorax with the abdominal segments, of which we shall have occasion to speak. The thorax is usually said to consist of three segments of the insect, viz. the second, third, and fourth segments, reckoning the head as one ; but this is not strictly accurate, as the fifth segment, in a partially atrophied condition, is very frequently, as here, intimately united with it, and in the Hymenoptera is included in front of the thoracico-*abdominal incisure, as we shall presently explain. Here, also, is seen the most typical form of the insect segment, equally removed from the simplicity of the abdominal and the high complexity of the cephalic rings. Each consists primarily of four pieces — a dorsal, a ventral, and two lateral plates, as seen in the ideal section, PI. II. fig. 9. The ventral plate is frequently called the sternum. Between the dorsal and lateral plates are placed the insertions of the wings, and those of the legs are found between the lateral and ventral plates. It is, however, by no means easy to follow out this ideal. The dorsal plate of the prothorax is very marked, being the large square plate between the head and the elytra (Pl. II. fig. 1 , pr) ; the ventral plate is also clearly marked, see PI. II. fig. 2, st ; it is the large piece extending in front of and between the coxse (ex). The lateral plates of this segment are not easy to trace. The French naturalist, Audouin, distinguished two parts in them, and illustrated them by dissections of the Great Water Beetle, Dylicus circumflexus. They are an anterior por- tion, the episternum, and a posterior portion, the epimeron. The former portion it is difficult to recognise at all in the Stag Beetle ; and the latter is the narrow piece, which, in PI. II. fig. 2, epim , is seen extending behind the coxa. On careful * See note to p. 21. 20 POPULAR SCIENCE REVIEW. dissection, however, this piece can scarcely be regarded as a plate forming a portion of the crust of the segment, so much as a process of the same, bent down behind the coxa, to assist in forming the acetabulum, or place of lodgment for the latter, and anchylosed with the posterior extremity of the ventral plate between the legs. It will be impossible, within the limits of this paper, to fully illustrate all the parts of which the thorax is composed. The two following segments are covered by the elytra and wings, which must be removed in order to reveal them. Having done this, we may find some difficulty at first in separating the mesothorax from the segment which follows, so firmly are they united to give solidity and strength to the body of the insect. By carefully bearing in mind, however, that this segment bears the elytra and intermediate legs, the separation can be effected ; and it will then be found that it is perfectly distinct. Its most prominent feature on the dorsal surface is the small triangular plate, which is just visible between the elytra before these are removed, and is termed the scutellum (figs. 1 and 3, scl.) We cannot dwell upon this segment further than to observe that, in consequence of the great development of the prothorax in front, and of the metathorax behind, it is, so to speak, almost crushed out between them, in conformity with a general law of animal organization, which requires that the excessive enlargement of any one part shall be accompanied by a corresponding diminu- tion in the parts adjoining it. In the Metabola, as has already been noticed, precisely the opposite of this occurs, the meso- thorax being predominant at the expense of the other segments. This segment, it should be noted, is composed of the same con- stituent plates as the preceding and following ones. The metathorax is the most highly developed segment of the thorax in the Coleoptera ; to it is assigned especially the function of flight, and the segment itself, and the great system of muscles contained within it, are both specially designed for this end. The dorsal plate is shown in PI. II. fig. 8. And here we may take occasion to notice the subdivision of its sur- face into four transverse parts, which Audouin, to whom we owe so much, was the first to point out. He regarded them as evidences of the ultimate subdivision of the elemental insect- ring into so many subsegments. These parts are perhaps better seen in the mesothorax of the Metabola, but are capable of demonstration here. They received from Audouin the fol- lowing names, viz. the pra3scutum, scutum, scutellum, and post- scutellum. Of these the scutum is that broad portion to which the wings are attached; following this is the scutellum, the anterior limit of which is not very obvious in this segment. This portion, however, is very well marked in the mesothorax, THE ANATOMY OF THE STAG BEETLE. 21 and lias been already noticed. The prsescutum lies in front of the wings, and the post- sent ellum, as its name indicates, follows the scut ellum. The two last-named subdivisions are generally bent downwards, to form attachments for the great longitudinal muscles of flight. In the lateral plates, just below the inser- tion of the wings, we again distinguish the episternum and epimeron ; but so altered are the relative position of these pieces by the great development of the sternum, that we can scarcely recognize them as anterior and posterior in their relative posi- tion, but rather as inferior and superior. They will be seen represented in PI. II. fig. 10. The sternum, or ventral plate of this segment, is the largest piece in the insect, and is divided by a central suture (see Pl. II. figs. 2 and 10). Although its typical position is between the legs, and indeed actually is so in some insects, it will generally be found in front of, rather than between, the coxae, as in the present instance ; it is of great strength, and gives origin to the great volume of muscles which occupy the lateral portions of the segment. Together with the greatly developed posterior coxae which lie behind it, it extends the ventral surface of the metathorax far beyond its dorsal limits, which are marked by the inwardly developed post- scutellum; and the consequence is noteworthy. The ventral plate of the succeeding or fifth segment of the insect has dis- appeared, only the dorsal plate remains (Pl. II. fig. 8) to occupy the vacancy caused by the deficient backward extension of the dorsal surface.* This plate in the Stag Beetle assumes the appearance of, and is continuous with, the succeeding dorsal plates of the abdomen ; but except at its posterior margin, it is connected on all sides with the metathorax ; so that from one point of view we may regard it as the commencement of the abdomen, and from another as the termination of the thorax ; thus illustrating the lack of that sharp separation between thorax and abdomen, in other words, the deficiency of regional distinction as compared with the Metabola which has been already referred to, while the great differentiation in form, in size, and in function, between the two wing-bearing segments, ranks the Coleoptera at once above the other orders of the Heterometabola with which it is associated. The abdomen is that portion of the body of the insect which most strikingly retains its original articulate form, fulfilling, as it does, the functions of nutrition and reproduction which are characteristic alike of the lowest as well of the highest types of the Articulata. Perhaps it will be better to regard with New- port the fifth segment just described as a piece by itself, the thoracico-abdominal segment ; then the true segments of the * This plate, as stated on p. 19, is in the Hymenoptera included with the thorax in front of the thoracico-abdominal incisure. 22 POPULAR SCIENCE REVIEW. abdomen will consist of tbe sixth and following ones. Of these, seven are visible on the dorsal surface, and two at least, if not three, are concerned in the formation of the reproductive organs, making fourteen or fifteen segments in the insect, counting the head as one. The dorsal and ventral plates are well developed, the lateral ones scarcely at all. In order to allow room for the respiratory movements, the dorsal plates are soft and yielding, sufficient protection being afforded to the upper surface by the strong covering of the elytra. In our review of the thorax, in order to give a more con- nected view of the several plates composing the same, we have omitted the subject of the wings and legs ; and these important organs must now claim some of our attention. In the Worms, whose habits of life require little facility for locomotion, every segment takes part in the act of progression, as is also the case with the larvae of insects themselves, at least those which undergo a complete metamorphosis ; but in the perfect insect, where much greater facility of motion is required, we find the locomotive appendages confined to the thorax, where they re- ceive their highest degree'5 of finish. In the Annelids each segment bears two pairs of lateral appendages, or rudimentary limbs, the superior being dorsal and the inferior ventral. The wings of insects would seem to represent the former, and the legs the latter. The prothorax of insects is not ordinarily pro- vided with superior appendages, but traces of such a provision exist in the pupae of the Diptera, where they are adapted as breathing organs, the anterior extremity of the great tracheal trunks being carried into them; they disappear, however, in the imago. The development of the wings may be most ad- vantageously studied in the common Cockroach, where they are seen to be gradually differentiated from the lateral portions of the dorsal plates of the wing-bearing segments. They are in principle sac-like processes of the integument, into which pass branches of the tracheal system. They thus always exhibit a double integument. The nervures are folds of the double integument, forming tubes along which the tracheae run. The elytra, beside their modification of form, differ from the wings chiefly in the greater amount of chitinous deposit they contain, and their consequently increased solidity. This thickening, however, takes place in the outer integument only, the inner one lying next the body of the insect being soft and membranous. Between the two, in the Stag Beetle, there is a vesicular layer (Pl. II. fig. 5), formed by the ramifications of the tracheae, ending in little bladders somewhat similar to those which occur in the body of the insect. This doubtless serves as a soft air-cushion to press upon the delicate wings beneath. The wings in this insect — as in most of the Coleoptera — are THE ANATOMY OF THE STAG BEETLE. 23 folded transversely beneath the elytra, the fold taking place at the point a in the drawing of the wing (PL II. fig. 11). The legs exhibit the joints usually observable in insects, viz. the coxa, femur, tibia, and tarsus. The coxae, or basal joints of the legs, are sunk in suitable cavities between the plates of the segments to which they belong,* so as to secure freedom from all possibility of dislocation, with a limited motion of revolution in an antero-posterior direction. The motion of the femora upon the coxae, is in a direction at right angles to this ; as is also that of the tibiae upon the femora. The tarsal joints (Pl. II. fig. 17) are five in number, and are connected with each other by a ball and socket- joint, allowing of a limited motion in every direction. The last tarsal joint is considerably longer than the preceding, and is hollowed out at its extremity to re- ceive the enlarged bases of the terminal claws with which it is armed, which lie side by side within it, and are free, like the joints of the tarsi themselves, to move, with certain restrictions, in every direction. Between the claws there is a small ap- pendage, terminating in two minute pencils of hairs. The ex- quisite finish of the tarsi of this insect is well calculated to excite our admiration, though this may perhaps be said of every part of the organization of living beings in general. The structure of the spiracles, perhaps, more properly belongs to a review of the respiratory system ; a description of the ex- ternal structure, however, would seem to be somewhat incom- plete without them. They are the external orifices of the respiratory tubes, by means of ^ which air is conveyed to every portion of the body of the insect. They occur in pairs, one on each side of the body, from the second to the twelfth segment inclusive, with the exception of the metathorax, which is un- provided with a spiracle. There are thus ten pairs of them, those of the thorax being larger than those of the abdomen. The former can only be observed by separating the segments be- tween which they occur, — one pair between the pro- and mesotho- rax, and the other between the latter and the metathorax. They really belong to the posterior region of the segment in front of them. The abdominal series commence with a pair on the dorsal surface of the fifth or thoracico- abdominal segment, and are rendered visible by the removal of the elytra and wings. Each consists of a thickened oval chitinous ring (Pl. II. figs. 12, 13, 14, and 19), within which is a more delicate, horny margin, fringed with branching processes (fig. 18), serving as a kind of sieve to exclude foreign matter. Within this, there is a valvu- lar aperture (figs. 12 and 13), one valve of which is provided with a handle-like process, into which is inserted a muscle aris- * The intermediate coxae are inserted between the sterna of the meso- and meta-thorax. 24 POPULAR SCIENCE REVIEW. ing from tlie margin of the spiracle at its superior extremity. The contraction of this muscle presses the valve which hears it upon the other, and thus closes the spiracle. It was originally intended to pass in review the whole of the structure of this insect, internally as well as externally. The subject, however, has run out to a greater length than was anticipated, and we must refrain at present from pursuing it further. The study of the development and anatomical structure of insects affords a vast extent of unbroken ground to many whose means of becoming acquainted with the broader aspects of the science of Entomology is, from various causes, limited to the observation of the familiar insects around them, and the extraordinary beauty and interest of the details which may thus be revealed may well prove the strongest incentive to master the drier technicalities of the subject which have occupied much of our attention in the preceding pages. Every part of insect structure will, on attentive examination, be found replete with what we may still delight to call Creative design. Does the House Fly or the Crane Fly sip its food by means which so long as they are unknown can excite but little in- terest ? Dissect them, and the secret of the process is revealed in a pumping instrument, which the skill of the mechanician can scarcely approach. With a view to facilitate the acquire- ment by the reader of a personal acquaintance with some of these interesting subjects, the following observations are offered as the result of the author’s experience. That patience and perseverance are necessary, it is scarcely needful to mention, as there is no royal road to knowledge of any kind. A certain amount of skill in drawing is highly desirable as a means of re- taining observations made, which if committed to memory alone would certainly be lost. Insects for dissection should be col- lected, not as single specimens, but a dozen or two at a time, when opportunity offers ; and if it is not convenient to make use of them at the time, they should be preserved in methylated spirit till wanted. By this means their internal parts are preserved, and the bleaching and hardening which they undergo is frequently an advantage, as it serves to render the nervous and muscular tissues more easily traced ; but this should not supersede the dissection of fresh specimens. The internal organs in all cases, and sometimes the external parts, should be dissected under water. A compound microscope, such as may be purchased for 51., is desirable ; and a dissecting microscope, similar to that recommended by the late Dr. Lawson, which, together with a suitable set of dissecting instruments, may be obtained from Collins for a trifle. The stage of this instrument is provided with a gutta-percha trough, to enable objects to be pinned THE ANATOMY OF THE STAG BEETLE. 25 thereto. A description of it may be found in Science Gossip for Sept. 1865. If artificial light be employed, a condenser should be provided to bring the rays of the lamp to a focus on the object. The internal soft parts will require to be teased out and floated away from their attachments with great care, and a jet of water directed upon the dissection occasionally from a small glass syringe will keep it clear from floating particles that would otherwise obscure the view. Clean sections made with a sharp strong knife through the thorax in different directions will show the disposition of the muscles. Yery small insects, or parts of insects, must not be pinned, but dissected in a shallow receptacle, such as a watch-glass, and occasionally transferred for closer scrutiny to the stage of the compound microscope. The tools used, in addition to knives of different shapes, as sold by opticians, should comprise a pair of fine dissecting forceps, the points of which should accurately meet ; and needles, straight and crooked, mounted in light wooden handles, may be easily made by the operator himself, and prove extremely serviceable. The following books of reference are recommended, viz. Burmeister’s Manual of Entomology , Shuck- ard’s Translation, 1836 ; Todd’s Cyclopaedia of Anatomy , Article ‘ Insecta/ by Newport ; and Lowne’s Anatomy of the Blow Fly. EXPLANATION OF PLATE II. Fig. 1. The Stag Beetle, natural size ; mx, the maxillae ; p, maxillary palp ; p', labial palp ; Ir, labrum ; c, clypeus ; a, antenna ; e, epicranium ; pr, prothorax ; sc!, scutellum of mesothorax. Fig. 2. Ventral surface ; mx, p, and p', as before ; m, mentum ; par, para- glossae ; sm, submentum ; dp, lateral margin of dorsal plate of prothorax ; st, sternum ; cx, coxa ; epim, epimeron. In the meso- and metathorax, the corresponding parts are marked with a single or a double accent respectively, thus, epis", the episternum of the metathorax. The following numerals indicate the ventral plates of the abdomen. Fig. 3. Dorsal surface of mesothorax and following segments, the elytra and one wing being removed, the other one remaining to show its transversely folded condition; el, attachment of elytron; scl', scutellum of mesothorax; epis', episternum of ditto ; scm", scutum, and scl", scutellum of metathorax. The numerals indicate the dorsal plates of the abdomen, each of which is seen to be furnished with a spiracle. The postscutellum is concealed. Fig. 4. Transverse section of elytron, showing the thickened outer and the membranous inner integument, with the vesicular layer between. Fig. 5. Portion of vesicular layer highly magnified. 26 POPULAR SCIENCE REVIEW. Fig. 6. Dorsal surface of Blow-fly. Fig. 7. Ditto of Cockroach. These two figures are introduced to illustrate the difference of structure between the Metabola and the Hetero- metabola, the prevalence of the regional distinction in the one, and of the segmentary division in the other. In the former, the whole of the central division of the body here visible consists of the meso- thorax, with the exception of the anterior angles, which belong to the prothorax. Fig. 8. The metathorax of the Stag Beetle, dorsal surface ; prs", the prsescutum ; w, the attachment of the wings ; g, membranous continuation of ditto ; sp, sp, spiracles of fifth and sixth segments ; 5, dorsal plate of fifth or ventrally atrophied segment, the thoracico- abdominal segment of Newport. The remaining letters as before. Fig. 9. Ideal diagram of an insect segment after Packard ; dp, dorsal plate ; lp, lp, lateral plates ; vp, ventral plate ; aa, dorsal appendages, the wings; aa, ventral appendages, the legs; ac, alimentary canal; ng, nervous ganglia ; dv, dorsal vessel ; tr, tracheae ; sp, spiracle. Fig. 10. Lateral view of mesothorax and following segments of Stag Beetle ; 11, lateral plates of abdomen ; vp, ventral plates of ditto. The remaining letters as before. Fig. 11. The wing unfolded ; a, the point where the fold occurs. Fig. 12. Abdominal spiracle, internal view, open; a, the aperture between the valves ; h, the handle ; m, its muscle. Fig. 13. Ditto, closed. Fig. 14. Ditto, external view. Fig. 15. Maxilla ; Is, the fringed superior lobe ; p, the palp ; st, stapes ; li, inferior lobe ; lac, lacinia ; car, cardo. Fig. 16. Labium ; lig, ligula ; par, paraglossae ; p', palp. Fig. 17. Tarsus of posterior leg. Fig. 18. Branching processes of abdominal spiracle. Fig. 19. Transverse section of ditto; m, the margin; p, processes; a, the aperture ; h, the handle. 27 ON FOG. By W. H. STONE, M.B. IT is hardly a matter of surprise that there should occur peri- odical crises of public excitement on the subject of London fog. Indeed, it is strong evidence of the influence of familiarity in securing toleration that so little attention is usually paid to it. To foreigners the thing is mysterious, and almost awful. The plague of Egyptian darkness, chronicled in Holy Writ as a direct interposition of Divine vengeance with the object of terri- fying a recreant tyrant into submission, is received with the hush of horror ; and yet the inhabitants of England’s metro- polis calmly endure an exactly similar infliction to that recorded in the book of Exodus, not only without terror, but almost without remark. It is even similar in the fact of an extremely definite line of demarcation by which the darkness is occasionally bounded, and by the transparency of atmosphere, the persist- ence of daylight, which causes neighbouring spots to resemble the land of Goshen. ‘No words,’ says Mons. Taine in his Notes sur V Angleterre, ‘ can describe the fog in winter. There are days when, while holding a man by the hand, you cannot see his face.’ He quotes, moreover, from a writer whom he terms ‘ the greatest contemporary English painter,’ a descrip- tion so graphic and so scientifically accurate as to be worth reproducing : — ‘ It was a foggy day in London, and the fog was heavy and dark. Animate London, with smarting eyes and irritated lungs, was blinking, wheezing, and choking ; inanimate London was a sooty spectre, divided in purpose between being visible and invisible, and so being wholly neither. Gaslights flared in the shops with a haggard and unblest air, as knowing themselves to be night- creatures that had no business abroad under the sun ; while the sun itself, when it was for a few minutes dimly indicated through circling eddies of fog, showed as if it had gone out, and were collapsing flat and cold. Even 28 POPULAR SCIENCE REVIEW. in tlie surrounding country it was a foggy day, but there the fog was grey, whereas in London it was, at about the boundary line, dark yellow, and a little within it, brown, and then browner, until at the heart of the city — which they call St. Mary Axe — it was rusty black. From any point of the high ridge of land northward, it might have been discerned that the loftiest buildings made an occasional struggle to get their heads above the foggy sea, and especially that the great dome of St. Paul’s seemed to die hard ; but this was not perceivable in the streets at their feet, where the whole metropolis was a heap of vapour charged with muffled sound of wheels and enfolding a gigantic catarrh.’ * Scientific opinion, however, is far from unanimous as to the exact nature of the phenomenon. A recent correspondent of the Times newspaper, Dr. Alfred Carpenter, who led off the latest crisis alluded to above, boldly jumped at the conclusion that fog is simply powdered carbon diffused in the air, and issuing as such from non- smoke- consuming fire-places. This view is, however, demonstrably erroneous. It is easy to pass a large quantity of very foggy atmosphere through a small fluid or cotton -wool filter by means of what is termed by chemists an ‘ aspirator ; ’ weighing the intercepting material before and after experiment. The increase of weight will be found infinitesi- mally small ; the microscope, moreover, shows at those times hardly any increase, and in some cases a decrease in the quantity of finely divided carbon, which is always, to a certain extent, present in the air of large towns. It can be noticed by every person that the days when those literal betes noires of the house- keeper, ‘ the blacks,’ fall on papers, books, and furniture, are not foggy, but the reverse, being usually dry, bright, and windy. And yet common sense and experience indicate some form of connexion between coal, smoke, and fog, of the ‘ London par- ticular ’ variety. Its practical limitation to our coal-burning metropolis, and to some other large towns, such as York, where the same conditions prevail, is a strong argument in this direc- tion. The writer’s personal observation supplies another fact of the same bearing. When he was a student in Paris in the year 1856, wood was still the fuel burnt in the close stoves of that city ; and the fogs which often delayed him on his journey to early morning visit at 7 a.m. in the old Hotel Dieu, though dense, were almost white, and like country mist. Napoleon III. was, however, encouraging the use of coal, and hearths for burning it were rapidly replacing the old poele, or the pair of dogs for supporting the burning log. Before his year of study ended, the character of the fog had materially changed ; no doubt owing to the altered fuel, and several well-marked specimens of the London * Dickens, Our Mutual Friend , iii. 1. ON FOG. 29 yellow variety came under his notice. Indeed, the surprised Parisians were energetically discussing the new invader as though it were Phylloxera, Aphis vastator, or the Colorado bug. The part which suspended carbon actually plays in coal- smoke seems to have been first correctly pointed out by the late Mr. C. Wye Williams in his Treatise on the Combustion of Coaly and the Prevention of Smoke. A pretty experiment as to its great light- extinguishing power is quoted by the writer of an excellent article on this subject in a weekly contemporary, the Engineer , to which once for all the writer may acknowledge his indebtedness : — ‘ The weight of carbon in a cubic foot of black smoke is not equal to that of a single grain. Of the extraordinary light- absorbing property and colouring effect produced by the in- appreciable myriads of atoms of this finely - divided carbon forming part of the cloud, some idea may be formed by arti- ficially mixing some of it, when in the deposited form of soot, with water. For this purpose collect it on a metallic plate held over a candle or gas-jet, and touching the flame. Let a single grain weight of this soot be gradually and intimately mixed on a palette, as a painter would with a palette-knife — first with a few drops of gum- water, enlarging the quantity till it becomes a spoonful. On this mixture being poured into a glass globe containing a gallon of water, the whole mass, on being stirred, will become opaque, and of the colour of ink. Whatever, then, may be the quantity or number of its atoms, we see from the cloud of incombustible matter with which this carbon is so inti- mately associated as smoke, that even attempting its separation and collection independently of its combustion borders on absurdity.’ 4 But even if it were possible/ says the same authority, ‘ to totally prevent the evolution of carbon in a finely- divided state, we should have advanced but a short way on the path to be trodden. The carbon renders, it is true, a fog dirty and dark, but it is not the carbon which is the principal cause of the sore throats, bronchitis, and “ colds in the head,” which are beyond question brought on by the persistent inhalation of London fog. These are more than probably due to the presence in the fog of sulphurous acid gas, carbonic acid, and carbonic oxide, the two last fruitful causes of violent headache. No matter how perfect the combustion of the coal might be, these gases would be as plentiful as ever. To illustrate this truth, we may cite the Metropolitan Railway. The engines on it burn Welsh smoke- less coal, and the conditions of combustion are made as perfect as science can make them ; but the tunnels are filled with an atmosphere charged with carbonic acid, carbonic oxide, and 30 POPULAR SCIENCE REVIEW. sulphurous acid. The utmost that could he attained by smoke- preventing grates would he the prevention of the discharge of carbon in powder. For the rest, the conditions would remain the same ; the fogs would be cleaner, and that is all.’ It is thus obvious that other modes of accounting for fog must be sought for besides the crude and simple hypothesis of suspended carbon. This view was well developed in a lecture by Captain Douglas Gralton, recently delivered at the meeting of the Balloon Society at Westminster Aquarium. He stated that from the surrounding of the sea the climate of England was more moist than many other climates, and had, therefore, a greater tendency to fogginess. In London fog resulted not alone from this cause and from the Thames, but from the exhalations of open spaces, where the rain had sunk into the soil. The canopy of compacted smoke from the 5,000,000 tons of coals annually used in the Metropolis prevented the evaporation of water, and caused the irritating effects of London fog. There were also the emanations from street- sweepings, manure-heaps, and the breath of millions of inhabitants, resulting, it was com- puted, in nineteen grains of sulphuric acid in every cubic yard of London air. Balloon experiments by Mr. Griaisher and others had proved that the fogs were not usually of high alti- tude, and that the sun was sometimes shining on high towers when all below was enveloped in mist. 75 per cent of light was thus intercepted, to the great detriment of animal and vegetable life, accounting, to some extent, for the comparative feebleness of London children. By way of reducing the dele- terious influences, open spaces should be well under- drained, and, if practicable, more spaces or boulevards laid out to admit freer circulation of air. While smoke from factories could be checked, every private house was in winter a manufactory of smoke and soot. The use of smokeless coal and of smoke-con- suming appliances would mitigate the evil ; but it seemed to him that private houses might eventually be supplied with heat from some central source by means of electricity. The best contribution, however, that we possess to the natural history of Fog is hardly so well known to the general public as it should be. This is mainly due to the fact that it is short and unpretending, and also to its being enshrined, and, to a certain degree, concealed, in the Proceedings of the Royal Society. On October 29, 1878, Prof. Frankland forwarded to his brother fellows a brief memoir occupying exactly three pages, but containing within this limited space very condensed and substantial matter. It is entitled, ‘ On Dry Fog/ and begins by stating the well-known fact that the foggy atmo- sphere, especially near large towns, is not always saturated with moisture. For instance, on the 17th of that month, at 3.30 p.m., ON FOG. 31 during a thick fog, the degree of humidity was only 80 per cent of saturation. The same phenomena had been observed by Mr. Glaisher in his balloon ascents, the hygrometer passing through cloud or fog often showing the air to possess considerable dry- ness. In an ascent from Wolverhampton in 1862, at a height of 9882 feet, in passing through a cloud so dense that the balloon could not be seen from the car, the dry-bulb thermometer read 37°’8 F., and the wet-bulb 30°*2, indicating a dew-point 17° '9 below the air temperature. On the 30th July of the same year, at an altitude of 6466 feet, while the balloon was passing between the Crystal Palace and Gravesend through c a great mist/ the dew-point was 120,7 F. below the temperature of the air. A table of sixteen such observations is given, in which, taking 100 as saturation, the real condition rises only once to 87, sinks as low as 46, and averages between 50 and 60, or rather more than half. It is thus evident, he observes, that air closely surrounding the spherules of water in a fog is some- times far from containing its full proportion of watery vapour ; ‘ although, as is well known to persons occupied with gas-analy- sis, when a perfectly dry gas is admitted into a moist eudiometer it very rapidly assumes the volume indicating saturation, not- withstanding that the proportion of water- surface to volume of gas is obviously far less than that afforded to the interstitial air of a fog/ One experiment was made to test the latter fact, and it was found that air dried over calcic chloride became completely saturated in less time than lm 50s, when passed into a moist glass tube, J inch in diameter. Dr. Frankland, in seeking for an explanation of the anomalous behaviour of the watery vapour in the two cases above, thought of some experiments made, many years ago, by Mr. Spence of Manchester, showing that the evaporation of saline solutions, kept just below their boiling point in open pans, can be almost entirely prevented by covering the liquid with a thin stratum of coal-tar. Mr. Spence in this way effected a considerable saving of fuel in that part of the process of manufacturing alum, in which burnt aluminous shale is digested for many hours with hot, diluted, sulphuric acid, by the lesser escape of steam from the surface of the hot liquid. He saw in this simple process a condition of things under which the so-called ‘ Dry Fog ’ might be produced. e From our manufactories and domestic fires/ he says, ‘ vast aggregate quantities of coal-tar and paraffin oil are daily distilled into the atmosphere, and condensing upon, or attaching themselves to, the watery spherules of fog or cloud, must of necessity coat the latter with an oily film, which would retard the evaporation of the water, and the consequent saturation of the interstitial air.’ 32 POPULAR SCIENCE REVIEW. Any person wlio lias used the ordinary paraffin lamp oil, 4 Ran- goon oil/ or similar hydro- carbons as lubricators for machinery, must be well aware what a firm and coherent film they instantly form on the surface of water, and even on polished metal. In the latter case, their great preservative power against rust and tarnish is no doubt mainly due to this property — a property which has of late been further utilized in surgery for the pro- tection from the air of raw wounded surfaces in man and animals. To test the exact amount of the difference of evaporation, two platinum dishes containing water, and presenting equal surfaces of liquid, were placed side by side in a moderate draught of air, the water in one being coated with a very thin film of coal-tar. It was found that during twenty-four hours the evaporation was reduced by the film of coal-tar by 84’4 per cent in one case, and by 78*6 per cent in another. In order to imitate more nearly the action of actual smoke in foggy air, the smoke from burning coal was then blown on the sur- face of the water in one of the platinum dishes, and the evaporation was thus reduced by 77*3 per cent. In a large bell jar, the air of which was kept dry by a large surface of concen- trated sulphuric acid, the effect of a film of coal- smoke varied, in six experiments, from 66*6 to 92‘7 per cent. All these concordant results are much too large to be acci- dental or erroneous, the only possible conclusion being that the real though vague connexion between fog and the imperfect combustion of bituminous coal, if not absolutely demonstrated, has thus, to a great extent, been explained and accounted for. Dr. Frankland remarks incidentally that the presence of liquid hydro-carbons in a diffused condition would also tend to explain the frequency, persistency, and irritating character of the fogs which afflict our large towns, inasmuch as some of the products of destructive distillation of coals are very irritating to the respiratory organs. It has long been well known to practical men that we burn our ordinary domestic coal to a terrific loss. It is still more disheartening to think that we convert it into an interceptor of the light of heaven, and into a dangerous bronchial irritant. The worst of the outlook is that the evil seems to be spreading. ‘ The fogs of the earlier portion of the present year were not confined to London. They formed belts which reached from Paris in the south to Liverpool in the north. The whole English Channel was shrouded in them. River traffic was stopped repeatedly by them in Liverpool. But it is none the less true that what in the country was a clear and comparatively harmless white fog, was in London a dirty and noisome fog/ And hereout comes a social paradox of no small dimensions, with whichDr. Siemens, more $wo,has not hesitated to grapple honestly. ON FOG. 33 It really seems as if we could burn our bituminous stores of fuel more economically, as we certainly can more pleasantly and healthily, by committing them to a preliminary sorting and separation into coke and gas. It will surprise no one at the present day to be told that slow, imperfect distillation in a small hearth is less thoroughgoing and perfect, and more liable to waste, than that of a gas retort. It is like bartering rough gold-dust against food and clothing, instead of having it first packed in neat circular blocks of equal value guaranteed by a government department. But, unfortunately, the middle-man, in the two cases, differs materially ; and until the average Englishman possesses more power than he now has over the gigantic gas monopoly, he is not likely to reap the benefits of the discovery. He has not as yet gained by the improved methods introduced of late years for equalizing the supplies of fresh meat in different parts of the world ; and if the butcher has been too strong for him in intercepting profits, how shall he struggle against the act-of-parliament protected gas companies ? As is usual in social questions of this order, the sufferer is himself most to blame. Coke is well known as a cheap fuel. It produces, when well managed, a brisk, cheerful, and singularly hot fire. But what householder of any experience has ever been able to secure its regular use in his domestic grate ? Ser- vants steadily, perseveringly, and heroically, refuse to touch it. If a store is kept in the cellar it is allowed to run out unnoticed, or, still worse, is buried beneath fresh and costly importations of new coal. Few householders, moreover, are aware that that sin- gularly repulsive, dictatorial, and generally unmanageable func- tionary the sweep carries away as refuse in his bag what he gains far mare by than he does by the money paid for the act of sweep- ing chimneys. Soot, which is only the difference between the waste coal and what has been converted into fog, is a valuable and most saleable commodity, which it is actually worth while to adulterate ! It is imitated by dyed sawdust, and commands, even when thus sophisticated, an excellent price. Mr. W. D. Scott Moncrieff, in a short paper headed 1 Smokeless London/ which appeared recently in Nature , proposes a very practicable scheme in this direction. He takes advantage of the existing plant of the gas companies, who, instead of taking 10,000 cubic feet of gas per ton from the coal, are to take 3333 feet, and to pass three times the quantity of coal through the retorts. They will thus have double the quantity of by-products in the shape of tar and ammoniacal liquids, the community will have 24-candle instead of 16-candle gas, the fuel resulting from the process will light readily and will make a more cheerful fire, giving out 20 per cent more heat than common coal without any smoke. He works out NEW SERIES, VOL. V. NO. XVII. D 34 POPULAR SCIENCE REVIEW. tlie proposition in some valuable statistics too long for quota- tion, showing that the yearly value of London smoke, now lost, amounts to 2,125,000/. Another important point to which attention has recently been drawn is the very partial and local character of a fog. Passengers by the Great Northern Railway, for instance, can easily observe its great prevalence in the valley below the ridge of clay hills termed the ‘ Hog’s Back,’ which form the northern wall of the basin of the Thames. On arriving at Finsbury Park, the line of demar- cation is often distinct and wall-like. Here, no doubt, the geo- graphical position, and the impervious nature of the strata, will account for the peculiarity. A similar case was noticed by Mr. White, the Secretary of the Royal Institute of Architects, on the 7th of December, in a letter addressed to the Times . He inquires whether the parks may not, in some degree, be respon- sible for the fogs which periodically obscure parts of London. The fog of December 2nd last is known to have prevailed prin- cipally in the northern, north-western, and western districts ; at the termini of the North-Western and Midland Railways great inconvenience was felt. Now, on the afternoon of that day, at about half-past four, Mr. White passed through the Regent’s Park, and there observed over a vast space, the circumference of which is three miles, a dense mass of bluish vapour rising, apparently, from the grass. In the midst of this vapour a feeling of damp cold was experienced, with a tendency to cough, while his beard and moustache were covered with globules of water. Objects at a few yards’ distance could not be distinguished ; both in the Euston Road and at Gloucester Gate the enclosure- walls of dif- ferent houses streamed with moisture. At a later hour, at 11.30 p.m., he was in Portland Place, where foot-passengers clung to the area railing as the only means available for directing their steps. Arrived, however, at Oxford Circus, the fog was less dense ; at the eastern end of Oxford Street comparatively little existed. He traversed the slums of Soho, Co vent Garden, and the Strand, without any difficulty, and the City was free from fog. 4 1 beg,’ he says, * scientific men who are interested in this matter to visit the Regent’s Park any day this winter between 4 and 5 p.m. I have been told that the drainage there is of an obsolete cha- racter, and from my experience of this and last year, when London has been visited with fog, the cloud has seemed to me to be thicker in Portland Place than in Oxford Street, or even in the Strand.’ The publication of the above letter gave rise to a lively correspondence, two independent correspondents confirming Mr. White’s facts ; and a third, Dr. G. V. Poore, adding the following comment : — ‘ If your correspondents will refer to Jordan’s Geological ON FOG. 35 Map of London, published by Stanford, they will find that Regent’s Park and Holland Park — two fog-haunted districts — are both upon the clay. The Holland Park district is indicated in this map by a tongue- shaped piece of clay wedged in between gravel to the east, and brick-earth to the west ; and it is pro- bably owing to this fact that fog is “ more dense in the imme- diate neighbourhood of Holland Park than in the streets of either Kensington or Hammersmith/’ which are both upon the gravel.’ On the 10th of the same month an interesting letter appeared from Paris, strongly corroborative of the writer’s views as given in a previous page : — ‘ The present agitation,’ says Mr. Sandeman, ‘ concerning fogs which is engaging so much attention in London may now be studied here with much greater advantage. The fuel consumed has undergone a remarkable change within the last ten years, and each individual can appreciate the change which has taken place in the frequency and density of our fogs, entirely attribut- able to the enormous increase in the consumption of coal. Ten years ago it was about 150,000 tons per annum as compared with 700,000 last year. Coal is rapidly replacing wood, and must continue to do so, on account of the much greater and yearly increasing cost of the latter. Paris has to-day been visited by a fog which would not lose much by comparison with one of our own London ones ; and the well-known electric lights of the Avenue de 1’ Opera were unable to penetrate it much better than their yellow gas confreres of the Rue de Rivoli. For Paris there is yet a chance, as all recognise the immense advantage of anthracite and other smokeless coals ; and, fortunately, the pre- sent generation can remember when this state of things was wholly unknown. In London we have been brought up to look upon it as an inevitable accessory of the winter months, but here there is a much more favourable opportunity for experiment and proof.’ Mr. Edwin Chadwick, at a recent meeting of the Society of Arts, contributed an essential factor to the discussion by noticing the effect of drainage in relieving a district of fogs ; instancing Richmond Park, which was once the site of heavy fogs and mists not contaminated by the 4 blacks ’ of London, but which are now comparatively free from them. Mr. Gr. J. Symons, at the same meeting, made some good practical observations, agreeing that fogs are due to a wet soil, and that they had been exceptionally intense of late years, because the years had been beyond the average wet ; but he denied that they were on the increase, or any worse than those of years ago. Low tempera- ture with high barometric pressure of the nature of an anti- cyclone he held to be, with a cold soil, the meteorological con- 36 POPULAR SCIENCE REVIEW. ditions of a fog. He thought that the large area built on in the Metropolitan district has tended to keep the amount of fog constant, the extra houses supplying smoke, and also lessening the extent of evaporating surface. Sir Francis Knowles gave, also, the result of his calculations on the effects of coal combus- tion in London. Taking the daily consumption at about 22,000 tons, there will be 166 lbs. of watery vapour per ton ejected by the chimneys. Nearly 4,000,000 lbs. of valuable ammoniacal liquor, with coal - tar and blacks, are, therefore, worse than wasted ; for there is about 13 lbs. of ammonia in the 166 lbs. of watery vapour. This waste may be almost entirely prevented by the often- suggested process of partially coking coal before using it. The liquors thus extracted from the coal would more than pay the cost of extracting them. The amount of ammonia annually wasted in London would be sufficient manure for six million quarters of corn. There are two elements in the physical history of fog which, in the recent discussion, seem to have been singularly neglected, namely, first, its very intense light- stopping power. This is obviously out of all proportion to the actual amount of carbon present. It has been shown in the pretty experiment given above that the quantity of pulverulent carbon necessary to produce the blackest smoke issuing from a river steamer’s chimney is small ; even this minimum, however, is signally absent from ordinary fog. The darkness of a dense fog is often, moreover, quite sepa- rable from opacity. We do not see moderately distant objects as if through smoke. Their outlines, where discernible, are distinct and unblurred. It is the light, and not the definition, which is deficient. Now it should be noted that exactly the same condition occurs with a snow-cloud. The blackness of an impending snow-storm is the only natural phenomenon which can in any way compare with that of fog. And yet we know that the impediment to light is situated in an infinite number of small masses of frozen water, in themselves transparent and lightly retractile. It is obvious that the same process is in action as that which renders a mass of transparent glass, when powdered, absolutely opaque : namely, the breaking up of the light by internal reflections and refractions of heterogeneous character. It seems far from improbable that this explanation may bear being extended to the case of fog, especially if Dr. Frankland’s hypothesis of its spheroidal cellular state be admit- ted. The yellowness may in such case be largely due to diffraction from bodies of very minute but similar size, bearing some simple ratio to the wave-length of yellow or orange-coloured light. Secondly, considerable corroboration of such a view may be de- rived from the fact mentioned by the Paris correspondent of the ON FOG. 37 Times, that the electric light hardly penetrated further than the ordinary gas flame : an observation which can be easily sub- stantiated on any foggy night from the parapet of Westminster Bridge. The gas flame is notoriously rich in yellow vibra- tions ; whereas those that give to the electric arc its dazzling and somewhat ghastly brilliancy belong to the violet, and even the ultra-violet end of the spectrum. Such vibrations would he entirely cancelled by an absorbent medium of mono- chromatic vapour, whose wave-length lay in the neighbourhood of the D. Sodium lines. It would he an interesting and com- plementary experiment to determine whether a strong Sodium flame would prove to he exceptionally transmissible through fog : certainly the red and flaring 4 links/ made of rope-yarn, plen- tifully served with pitch, which used to be brought out on such occasions, and which were in the last century carried by foot- men behind private carriages, seem to point in this direction. The causes, then, of Fog, may he fairly divided into those which are climatic, and others which are due to the use of mineral coal. Besides these two, locality and geological struc- ture must not be overlooked. It is not only unnecessary, hut unscientific, to refer points needing investigation of this cha- racter to ‘ some magnetical changes/ the nature of which is not apparent. This absurd proposition was actually sustained 1 ?y Dr. Carpenter at the Society of Arts, and fairly deserves the comment of a scientific contemporary, ‘We fancy that Dr. Carpenter has written without taking time to think, for it is certain that his letter contains some fallacious reasoning based on a want of knowledge of the facts.’ Very different as specimens of patient induction, free from hasty jumping at irrelevant conclusions, are the views of Dr. Frankland given above : probably they approach more nearly to a scientific solution of the enigma than any others. But when the question of practically remedying an acknow- ledged evil is raised, the matter becomes more complicated and difficult : indeed, different minds seem to have approached the topic by various avenues of thought. Captain Gfalton, in his lecture, lays especial stress on the climatic and geological element. ‘ The London basin/ he says, ‘ may be described generally as formed of clay, which retains the moisture from rainfall ; deposits of gravel rest in many places in the clay. These deposits are not usually of great depth. The river Thames runs through the centre of London. The surface of the metropolitan area when built over, is generally well drained, and all mois- ture which falls is rapidly removed ; but there are numerous spaces not built over, where the rain sinks into the soil, as, for instance, the parks, squares, gardens, &c., and there are also 38 POPULAR SCIENCE REVIEW. bodies of water in London which contribute moisture. These may be noticed as constituting a local cause of fog. Indepen- dently of the local cause of fog, which, no doubt, may always be mitigated to some degree, there remains the permanent cause, which arises from the geographical position of England — a com- paratively small island surrounded by the sea — and that is a cause over which we can have no control.’ Whereas another authority’s confession of faith ‘ consists in stating that London fogs are due to London smoke — are, in fact, frequently made up of smoke, and nothing else ; and that if we could get rid of smoke we should probably be rid of fogs at the same time.’ Probably the truth lies somewhere between these two extremes ; the correlative remedies being better drainage, and more perfect and economical combustion of our bituminous fuel. The former reform must be left in great measure to public bodies — such as the Metropolitan Board of Works. The latter is to a great extent in our own hands, and will amply repay closer attention than it now obtains. The mere use of coke instead of coal for domestic fires, if sedulously and perseveringly insisted on in opposition to the prejudice and obstinacy of ser- vants, will achieve much. In time Dr. Siemens’s apparent para- dox that it is better and more economical to divide our raw coal preliminarily into two manufactured products, gas and coke, before recombining them in a properly constructed hearth, may prove a truth of practical application, and may be made to save for use many costly by-products now lost and allowed to do injury. Captain Galton makes a good suggestion, — ‘ Open spaces should be created. Of course, if we could cut London in two from north to south by a broad open space, as it is cut in two from east to west by its river, it would do something to break up the cloud of smoke. In the year 1 852 Sir Joseph Paxton proposed to carry a broad boulevard round London. It was a very feasible scheme in those days ; it is a pity it was not carried into effect. Open spaces carefully under- drained, and so situated as to favour the circulation of air through the centre of London, would form a most important feature in promoting the health of London, if such things were possible.’ It remains to be seen how far his proposed object will be furthered by the great arterial streets from Holbom to the Strand now in contemplation. As regards the decarbonization of domestic smoke the ques- tion is more arduous. In our household fire-places the tempera- ture is never very intense, the supply of air ample ; the smoke is evolved only because the temperature is not high enough to cause ignition and combustion of the gas and suspended car- bon. It is not practicable in any open fire to get a sufficiently ON FOG. 39 high, temperature to secure the required end. Automatic or closed stoves of all kinds seem out of the question, and, indeed, make as much smoke as an open grate ; only it is not seen till it escapes at the chimney- top. Another, and far more hopeful scheme, is advocated by a writer in the Engineer , a class paper already referred to, and which is specially qualified to speak on such a subject. It has the advantage that it 4 would leave us our open fires and our coal just as they are. It consists in depriving the smoke of its sus- pended carbon. To a large extent this is done for us already by our chimneys. The sweep every year takes away enough soot to render London fogs — were it found in them — ten times worse than they are. There is every reason to believe that the partial or total cleaning of household smoke is not at all beyond the reach of the inventor who will approach the subject with an intelligent perception of facts. Why is it that much of the soot is now deposited in our chimneys P The answer is that the particles come in contact with the sides, lose their velocity, and fall, or adhere to the bricks. It is well known that wherever an eddy can he formed in a chimney there will soot he deposited in quantity. Soot is delivered from the top of a chimney solely because the particles are very small, so small that their superficies is enormous as compared with their solidity. Consequently they are when set afloat in a current of air easily borne up and carried to the top of the chimney. Once there the current is gone, and they fall by their own gravity as a shower of “blacks.” How, if the velocity is once taken out of them and they are not permitted to be caught up by a current again, we are done with them as far as smoke is concerned. To get rid of them we must do just what is done in getting moisture out of steam — permit the current to strike a series of flat surfaces from which it is deflected. These sur- faces, so to speak, “ knock ” the water out of steam. The prin- ciple has been very elegantly employed in a gas purifier which we illustrated in our pages not long since. The object in view is to get rid of carbon in suspension in the gas.’ That such a plan could be rendered efficient ‘ is certain, but that trouble and expense would be incurred must not be denied. Its great claim to popular support would consist in the fact that its adoption would interfere with no popular prejudice in favour of open fires and their existing management. * 40 SOME FACTS ABOUT FISHES. BY THE EDITOR. RECENT researches, and especially those explorations of the deep sea which have been systematically carried on of late years, have brought to light numerous interesting facts in rela- tion to fishes. Some phenomena previously altogether unsus- pected have come to our knowledge, whilst others have been shown to be of far more general occurrence than has hitherto been supposed. In the present article we propose to call attention to one or two prominent points brought out by late investigations. Anything like a true metamorphosis is of very rare occurrence among fishes. Indeed, the only change which can, to a certain extent, be compared with the metamorphosis of the Batrachia, is presented by the Lampreys ; and even in them the change from what we must call the larval condition to that of the adult, is by no means so great as that from the tadpole to the perfect frog or newt. The lampreys, as most people are aware, are eel- shaped, scaleless fishes of very low organization, destitute of paired fins, having on the head a pair of eyes and a single nasal aperture, and on each side behind the head seven aper- tures belonging to an equal number of branchial sacs. The mouth, which is situated quite at the anterior end of the animal, is formed by a shallow, circular cavity, at the bottom of which the actual opening is situated, having a peculiar horny tooth above and another below it, and a similar armature upon the tongue, which occupies the aperture. Besides these the inner surface of the funnel-shaped cavity has nu- merous conical teeth, which are really the horny coverings of so many small papillae ; and these are of use to the animals when attaching themselves by suction to other objects. In fact, they adhere by their mouths to the stones at the bottom of the streams which they frequent, and thus, without much bodily exertion, they resist the action of the current (from this habit SOME FACTS ABOUT FISHES. 41 the generic name of the Lampreys, Petromyzon, or Stone-sucker, is derived) ; but they also avail themselves of their power of adhesion for a less peaceful purpose, attaching themselves in this way to the bodies of other fishes, whose flesh they then consume by means of their larger teeth attached to the jaws and tongue. In this perfect condition, so far as their habits are known, the Lampreys must be regarded as decidedly predatory fishes. The streams inhabited by Lampreys are found to harbour another fish of very similar form, which, from its habit of con- cealing itself in the sand of the bottom, has long been known as the Sand-pride (Pride being a local name for the small river lamprey), and, under the generic name of A mmoccetes, regarded as a distinct form of the Lamprey family. In general form it is like a lamprey ; it is equally destitute of paired fins, and has also seven branchial apertures on each side near the head ; but the eyes are exceedingly small, deeply seated, and concealed beneath the skin, and the mouth, instead of constituting a cir- cular suctorial organ, is a horseshoe-shaped cavity, surrounded in front by a sort of membrane, and furnished internally with numerous slender papillae, but destitute of horny teeth, and quite unfitted for attaching itself by suction to any object. The food of the Sand-pride appears to consist of minute aquatic organisms, obtained from the sand or mud in which it lives. The researches of Dr. August Muller first revealed the exist- ence of a more intimate relation between the Ammoccetes and the Lampreys, than that implied in their belonging to the same family, and to nearly allied genera. By observing the small river lampreys in the act of spawning and securing the spawn, that naturalist was enabled to watch the development of the embryos in the eggs, and was rather surprised to find that the young fish produced, after growing for a short time, presented all the cha- racters of the Sand- pride or Ammoccetes. Subsequently he ob- served the transformation of the Ammoccetes into the Lampreys ; but the most remarkable point about this metamorphosis is that it is comparatively sudden : it is not until the fourth year of its existence that the fish passes from the larval to the adult con- dition, and the metamorphosis is effected by a series of changes taking place rather rapidly, thus reminding us somewhat of what occurs in insects, rather than of the gradual modification of the Batrachian larvae. From the occurrence of Ammoccetes in the fresh waters of various parts of the world where river lampreys have been met with, it would appear that this me- tamorphosis may be regarded as general throughout the Lam- prey family, although as yet nothing seems to be known of the transformations (if any) undergone by the Marine Lampreys. A minor change, also partially analogous to what occurs in 42 POPULAR SCIENCE REVIEW. the Batrachia, is to be found in the presence of external branchial organs in the embryos of Sharks and Bays, and in the young of certain Ganoid fishes, especially of Protopterus , the African Mudfish. These branchiae, as in the Tadpoles of frogs and newts, disappear in the further development of the fishes, the last named of which, in many respects, seems to lead from the true fishes towards the Batrachians. But although we cannot say that an actual metamorphosis occurs in any other fishes, it has long been known that changes do take place in some of them, and that in many cases the young fishes differ very considerably from the adults. It is only of late years, however, that any conception has been arrived at of the extent to which these changes may attain ; and it is mainly to Dr. Gunther, the keeper of the Zoological Department in the British Museum, and to Dr. Lutken of Copenhagen, that we are indebted for the knowledge of the changes of form occurring in fishes that we now possess ; the former gentleman having described numerous instances in various memoirs published during the last twelve years ; and the latter being the author of several scattered papers on the subject, and quite recently of a valuable memoir on the changes observable in fishes of the Atlantic,* in which he has summed up and illustrated many of his own and Dr. Gunther’s results. Dr. Lutken proposes to deno- minate these changes of form 4 hemimetamorphoses.’ Dr. Gunther has also devoted a chapter in his recently published and admir- able Introduction to the Study of Fishes to a general consideration of these phenomena. Without figures, both of the different young forms and of the adult fishes, it is of course, in many cases, impossible to convey an intelligible idea of the changes which have been brought to light by the investigations above referred to, but we will endeavour to describe two or three of them so as to enable the reader to see the bearing and importance of such results as have been, or may be, obtained in this field of research. The occurrence of important changes in the so-called ‘ Flat fishes ’ ( Pleuronectoidei ) has long been known, but as they are very curious we may devote a few words to them here. These fishes, of which the turbot, the plaice, and the sole, are well- known examples, always have the body broad and much com- pressed from side to side ; they live upon the bottom, where they are in the habit of lying quietly, and the two sides of the body are differently coloured, — that which is kept habitually downwards and applied to the ground in repose being of a white * 1 Spolia A tlantica/ in Kongl. Danshe Vidensk. Selshabs Skrifter , frth series. 1680. This Memoir is in Danish, but the author has appended to it a r£sum6 in French, a translation of which will appear in the Annals and Magazine of Natural History, SOME FACTS ABOUT FISHES. 43 or pale colour, while the opposite surface, which is turned upwards, is of a darker tint, and apparently coloured to secure concealment by its resemblance to the surrounding sand, &c. In many fishes — perhaps in most — we may remark a similar difference between the coloration of the upper and lower sur- faces ; hut in these it is the hack and the belly that afford the contrast, whereas in the Flat-fishes the two sides of the body are thus differently coloured, and the animals swim and lie upon the bottom in a position at right angles to that taken by all other fishes. The long fins which fringe the two edges of the body of a sole or turbot, are really the dorsal and anal fins. In order to fit the Pleuronectid fishes for this peculiar con- dition of life the two eyes are both placed upon the same side of the head, the coloured or upper side, where alone under ordinary circumstances they could be of any use to the animal ; and this is associated with a curious contortion of the bones of the skull, and a twisting of the mouth of the fish, such as often gives it a very singular aspect. When very young, however, the Flat- fishes do not present any such peculiarities : they are perfectly symmetrical, transparent little creatures, having one eye on each side of the head like other fishes, and they swim in a ver- tical position, like any other deep-bodied member of their class. The change from the symmetrical condition of the head in the young fish to the distorted form which it presents in the adult, takes place at a very early period, but how this wonderful con- version is effected does not seem as yet to be quite satisfactorily made out. 4 Whilst some naturalists/ says Dr. Gunther, ‘ believe that the eye turning round its axis pushes its way through the yielding bones from the blind to the upper side, others hold that, as soon as the body of the fish commences to rest on one side only, the eye of that side, in its tendency to turn towards the light, carries the surrounding parts of the head with it ; in fact, the whole of the fore-part of the head is twisted towards the coloured side, which is a process of but little difficulty as long as the framework of the head is still cartilaginous.’ * A j 'priori , the second explanation seems to be by far the more probable one, and we must confess that we thought it had been finally established by Dr. Traquair in his valuable memoir published by the Linnean Society, t This change in the Pleuronectidse, from its nature, the importance of the organs affected by it, and its singularly abnormal results, may perhaps be regarded as an extreme in- stance of ‘ hemimetamorphosis but from the very early period in the life of the fish at which it occurs, and its uniformity * Introduction to the Study of Fishes, p. 553. t Linnean Transactions , vol. xxv. p. 263. 44 POPULAR SCIENCE REVIEW. throughout a considerable group of fishes, to which it is limited, it does not affect ichthyological researches in the same way as certain less profound alterations occurring in other types of fishes. It is for the knowledge of these that we are more especially indebted to the investigations of Dr. Gunther and Dr. Liitken. One of the commonest peculiarities of young fishes is the presence on the margins of the opercular bones, and especially of the prseoperculum, of numerous denticulations, which are gradually effaced by the growth of the bone, and are altogether wanting in the adult. In other cases certain bones belonging or in immediate contiguity to the head, such as the praeoperculum, supra- scapula, and humerus, become enormously developed, forming large plates, which regularly cuirass the front half of the fish or the greater part of it, and from these and other bones of the head formidable spines or other processes may be developed. Dr. Gunther figures a young Pomacanthus , in which the supra- scapular and prseopercular plates are thus produced into immense spines, the former concealing the fore- part of the dorsal fin, and the latter entirely hiding the ventrals. In this well-armed infant the frontal bone is produced over each eye into a long, pointed, lancet-shaped spine ; and altogether, small as it is, this young fish would probably be a very uncom- fortable morsel to swallow. In another similar form the frontal spines, instead of being straight and pointed, represent long, curved horns. These cuirassed young fish were formed into a distinct genus, named Tholichthys (in allusion probably to the dome-like bony front of the species first described) ; they are now recognized as constituting a stage in the development of certain fishes belonging especially to the Chsetodons and the allied groups Carangidae and Cyttidae. In many different forms strong spines are developed from various bones of the head and operculum, without any special dilatation of these into bony plates, as in the Tholichthys ; and, no doubt, in these cases also the protection of the young animals from the assaults of their enemies, is the office of these com- paratively formidable armatures. Such opercular and cephalic spines are characteristic of the young Swordfishes, in which they spring from the parietal and prseoperculum, and attain formidable dimensions ; and in these and other cases where the spines are greatly developed, they must, doubtless, be partially got rid of by absorption, or thrown off as the fish advances towards maturity. The development of the Swordfishes is particularly instructive, and we shall therefore endeavour to describe the stages through which they pass. The Swordfishes, the largest forms of the ordinary bony fishes ( Teleostei ), sometimes attaining a length of twelve or fifteen feet, constitute a family not far removed from the SOME FACTS ABOUT FISHES 45 Scombridse, represented by tbe Mackerels and Tunnies, of which the latter also attain a large size. They have a robust, spindle- shaped body, tapering gradually towards the tail, which is an exceedingly powerful organ, enabling these fish to travel through the water with great rapidity. The two principal genera are Xiphias and Histiophorus ; the former, characterized, inter alia , by the total absence of the ventral fins, including the Swordfish so common in the Mediterranean {Xiphias gladius), which also occurs in more northern seas, and is occasionally taken off the British coasts ; the latter, in which the ventrals are represented by a pair of long, pointed, styliform appendages, being confined to the tropical and subtropical parts of the two great oceans. In both genera nearly the whole length of the back is occupied by a very high dorsal fin (especially elevated in Histiophorus ), but which is usually more or less worn away in old specimens ; and in both the upper jaw terminates in a long bony spike, the so-called sword, formed by the maxillaries, prsemaxillaries, and vomer, and projecting far beyond the anterior extremity of the lower jaw. This sword, which in large specimens may attain a length of two or three feet, with a diameter of two or three inches towards its base, constitutes a most formidable weapon, with which the swordfish is said to attack whales and wound them severely, for what purpose is not known. Sometimes, with a gallantry like that exhibited by Bon Quixote in his celebrated attack on the windmills, and probably urged by a somewhat similar mistaken impulse, the swordfish will assault a passing ship or boat, and the power of the fish in the water is so enormous that it will drive its weapon a long way through even a thick plank. Such exploits, however, are performed at the cost of the weapon, for the unfortunate swordfish, being unable to withdraw its beak, its struggles to get free, aided probably by the motion of the vessel through the water, generally break the bone short off. The jaws are toothless. The characters presented by the young swordfish for some time after their exclusion from the egg are exceedingly different from those above described. In general, the changes undergone appear to be very similar in the two principal genera already mentioned ; but as the series of forms described is more complete in the case of Histiophorus , we may take this as our example. The earliest phase known in the development of Histiophorus is described and figured by Br. Lutken, and is certainly as un- like its parents as any young creature would wish to be. The specimen measured only about one-fifth of an inch in length, and was probably not long out of the egg when it was captured, and consigned to the spirit-bottle. The body terminates in front in a head much larger in proportion than in the adult swordfishes, and tapers off behind the head to a comparatively 46 POPULAR SCIENCE REVIEW. slender tail, marked on each side with a small ridge (a character which also occurs in the adults), and furnished with a very small, entire fin. On each side of the head is a large, round eye, and in front of this the forehead of the little fish descends rapidly to the base of a slightly projecting beak, which, however, is not so long as the diameter of the eye. The beak includes both jaws, and the upper jaw is very little longer than the lower one ; the jaws open quite back under the eyes, and both of them are armed with comparatively strong teeth, those at the apex of the jaws being stronger than the rest, and curved. The spine springing from the prseoperculum is much longer than the short round pectoral fin, and the edges of this and of the parietal spine are finely serrated. Small spines occur both above and below the prseopercular spine, and over each eye there is a small supra-orbital spine, which, however, disappears very early. Be- sides the pectoral fins, which show indications of rays, and the caudal already mentioned, there are rudimentary dorsal and anal fins, consisting simply of membrane, with no trace of rays. It will be easily seen that such a little creature as this has scarcely any resemblance to the adult swordfish ; and, indeed, Dr. Liitken says that but for the previous knowledge of the developmental stages of these fishes, his youngest forms would rather have been referred to some fish allied to the Flying Giurnards (Dactylopterus). This youngest stage is made known by one of a series of small fishes advancing from rather more than one-fifth of an inch to rather less than half an inch long ; and the whole of these, Dr. Liitken says, differ very little from each other, the principal difference ap- parently being that the younger the fish, the shorter and broader is its little beak. Nevertheless, the largest of Dr. Liitken’s earliest series exceeds in length the specimen on which Dr. Gunther’s first stage was founded, as this was only 9 milli- metres (rather more than one- third of an inch) long, although it already shows signs of a more advanced development. The general form of the fish more nearly resembles that of the adult, although the head and eyes are still of rather disproportionate size ; the forehead still falls abruptly in front of the eye ; but the beak is comparatively longer, although the jaws are still nearly of equal length, and armed througnout with teeth. The spine above the eye, and the small spines on each side of the pra;opercular spine have apparently vanished ; the prseopercular spine itself is comparatively longer than in Dr. Liitken’s earliest form ; the dorsal and anal fins form low but distinct fringes, quite separate from the caudal, which is already rayed and forked; and beneath the pectorals small rudiments of the ventral fins have made their appearance. In a second stage, a fish, but little more than half an inch in length, is described and figured by Dr. Gun- SOME FACTS ABOUT FISHES. 47 ther as haying the head more nearly in proportion to the body, although the eye is still large and the forehead steep, but less so than in that just noticed ; the beak is still formed of the two jaws, fully armed with teeth, hut the upper jaw slightly exceeds the lower one ; the dorsal fin has become much more elevated, and, with the anal fin, is already furnished with rays ; and the ventrals have become developed into long styliform appendages. A third specimen, about 2J inches (60 mi Him.) long, has already acquired nearly the form and proportions of the adult; the upper jaw is considerably produced beyond the apex of the lower one, and both jaws have lost their armature of teeth ; the parietal spine has vanished, and the praeopercular one is com- paratively small, while the fins have attained pretty nearly the proportions which they have in the full-grown fish. The little animal is, in fact, an unmistakable Swordfish, and only re- quires a little further elongation of the beak formed by the upper jaw to be a close likeness of its parents. The Garfish, forming the family Scomberesocidse, and one species of which, the common Garfish or Greenbone (Belone vulgaris ), may not unfrequently be seen in the fishmongers’ shops, present phenomena of development to some extent analo- gous to those observed in the Swordfishes. The adult fish has both jawsmost curiously prolonged into slender-pointed beaks, of which, i however, the lower one is the longest ; but in the very young fish, although the form and general character are very similar ito those of the adult, there is not a trace of this singular pro- longation. It soon begins to make its appearance, however, and the length of the jaws gradually increases until the mature form is attained. In the course of this development, the dispropor- tion between the two jaws is for a time very considerable, espe- cially in the common Garfish, which at one period seems to reverse the characters of the Swordfish, having the lower jaw produced into a long slender beak, while the upper one is not remarkably elongated. The development of some fishes of the genus Holocentrum, a somewhat perch-like group inhabiting tropical seas, presents a contrast to that of the Swordfishes in another way, — the young fishes are furnished not only with opercular and cephalic spines, which afterwards disappear more or less, but also with a pro- jecting beak from the upper jaw, which is often serrated, and sometimes forked at the apex, but which always vanishes as the fish approaches maturity. These young forms of Holocentrum , and of the allied genus Myripristis , have been described as form- ing distinct genera under the very appropriate names of Rhynchichthys , Rhinoberyx, and Rhamphoberyx. It would carry us too far to attempt to indicate anything like the whole of the phenomena presented by fishes in their 48 POPULAR SCIENCE REVIEW. development. We find in some special developments of tlie fins, or of parts of them, as in the case of the pectorals of the Flying Gurnards (Dactylopterus) , and the separate filaments of the ventrals in the true Gurnards ( Trigla ) ; or certain of the fins undergo a change of position and function, as in the so-called Pediculati, of which the Fishing-frog or Sea Devil ( Lophius piscatorius) may he taken as an example, in which, by an elon- gation of the carpal hones into a sort of arm, the pectoral fins, originally widely expanded, lateral organs, are converted into something very like feet, upon which the fishes rest and move about at the sea-hottom. The young Fishing-frog, in fact, although presenting a considerable family likeness to its parents, differs from them in some respects very remarkably, especially in the great development of the pectoral and ventral* fins, in the curiously-branched structure of the free dorsal spines behind the filament which hears the so-called * bait ’ immediately over the mouth, and the great elongation of the fin-rays in general, which are for the most part produced into long filaments. Similar filamentious prolongatons of some of the fin-rays occur in many other young fishes, and most strikingly in some of those curious inhabitants of deep water, the Ribbon fishes, the young of which are frequently captured at the surface, although the adults have never been met with there, except in a dead or dying condition. The young of Trachypterus, a genus of Ribbon fishes, examples of one species of which (the Deal-fish, Tra- chypterus arcticus) are generally thrown upon the northern coasts of Britain after the equinoctial gales, exhibits this pro- longation of the fin-rays in a most striking manner. The adult fish, which may attain a length of six feet, and which has a body shaped like a thin, broad, tapering blade, has a dorsal fin extending the whole length of its back, but with the foremost portion, situated above the head, separated from the rest of the fin, above which it rises to a considerable height, being supported upon very long flexible spines. The pectoral fins are small ; the ventrals, situated beneath them, long, and supported by few rays ; whilst the tail terminates in an obtuse tip, from the dorsal surface of which the caudal fin rises, nearly at right angles to the long axis of the body. In the young Trachypterus , which is also a thin, flat-sided fish, having a dorsal fin running the whole length of its back, the caudal fin, which is consider- ably larger in proportion than in the adult, is set on the tail in the usual way; the rays in the front portion of the dorsal, above the head, are enormously prolonged, forming free fila- ments, extending to three or four times the length of the body of the fish, and having in their course numerous lappet-like dilatations; the rays of the ventral fins are also considerably produced. SOME FACTS ABOUT FISHES. 49 Of course we have been unable to give more than a general indication of the nature of these remarkable external changes in this very rapid and imperfect sketch. But we must notice that in many cases changes occur in internal structure of quite as great importance as those to which we have alluded. Among other things, the dentition frequently undergoes most remarkable alterations, and this is a matter of great con- sequence in relation to systematic ichthyology, and especially to the interpretation of the fossil remains of fishes. In fact, we may say broadly that a great proportion of young fishes differ from their parents by characters which would be regarded as sufficient for the establishment of new genera and species, if occurring in adult fishes ; and hence it will be easily understood that, with the fragmentary acquaintance that we necessarily possess of the fish fauna of the high seas, and even of the shores of tropical countries, great numbers of young forms have already been described as independent genera and species. The two distinguished ichthyologists whose names were mentioned at the beginning of this article, and from whose writings most of its materials have been derived, have already indicated a great number of important systematic changes of this kind, which must be made in conse- quence of the recognition of the facts here briefly and im- perfectly described. But a study of these works shows that while considerable progress has been made, much more still remains to be done. The changes referred to appear to be most strongly marked in pelagic and deep-sea fishes, which are not only difficult to get, but naturally so widely distributed, that it is only by lucky accident, or by long- continued inves- tigation, that we can hope to bring together the successive forms of a species so as to work out its development. NEW SEMES, VOL. V. — NO. XVII. 50 REVIEWS. THE CHALLENGERS VOYAGE* IN this handsome quarto volume we have the first instalment of the final report on the results of the great exploring voyage of the Challenger , and if the rest of the work answers to the sample, the country, and especially British naturalists, will have every reason to he satisfied with the outcome of this expedition. In the Provisional Preface to this first volume, Sir Wyville Thomson explains generally the plan of publication that is being adopted ; and it seems excellently calculated to place the scien- tific results of the voyage in a convenient form in the hands of the public. These results naturally divide themselves into two series. One of these consists of the hydrographical details, and magnetic, meteorological, and other physical observations which naturally fell to the lot of the Naval Surveying Staff ; and their reports, with the addition of Mr. Buchanan’s investigations of the specific gravity of sea-water at various depths and under various conditions, will occupy two volumes of the series. The complete report is estimated to form fourteen or fifteen volumes, similar to the one now before us, so that twelve or thirteen volumes are left for the record of the doings of the Scientific staff. One of these is to be given up to the inves- tigation of the recent deposits on the bed of the ocean and their bearing an Geology and Petrology, by Mr. John Murray and the Abbe Renard ; and another, which is to be the final one of the series, to a discussion of the general chemical and physical results of the expedition ; the zoologists to whom the collections made during the voyage have been confided will thus have ten or a dozen stout quartos in which to disport themselves, and enormous as the mass of specimens undoubtedly must be, we cannot help feeling that they ought to have room enough. The Zoological contributions will make, according to Sir Wyville Thom- son’s statement, about fifty separate memoirs, and the mode of publication to be adopted is somewhat as follows : — Each memoir and its plates will be paged and numbered separately, and as soon as a sufficient number of memoirs * Report on the Scientific Results of the Voyage of H. M. S. Challenger , during the years 1873-76, under the command of Captain George Nares, R.N. , F.R.S., and Captain Frank Turle Thomson, R.N. Prepared under the super- intendence of Sir C. Wyville Thomson, Knt., F.R.S., &c. 1 Zoology,’ Vol. I. Published by order of Her Majesty’s Government. 4to. London, 1880, REVIEWS. 51 has been collected to make a volume of the proper size, they will be at once printed, bound together, and issued with provisional title-pages and prefatory matter. Thus, while the work is in progress, the published part will always be in a state fit for reference, and those who choose may keep it always in its original form ; but on its completion, fresh title-pages, tables of contents, &c., will be issued, in order that the different memoirs may be brought into regular systematic sequence, according to the nature of their contents. An inconvenience which would naturally arise from this rearrangement, namely, the loss of all indications of date of publication, has been obviated by a very simple plan, — each separate memoir will have its own number as part of the report on the Zoology of the Challenger Expedition, and each sheet will have at the foot of its first page the indication of the part to which it belongs and the date of publication of that part. Volume I., now published, contains six parts, thus numbered consecutively. In his general introduction to the Challenger Reports on Zoology, with regard to which, he says, he must be considered only in the light of the Editor of the whole work, Sir Wyville Thomson describes the general objects and arrangements of the Expedition very much in the same terms as in his previous book, giving an account of operations in the Atlantic, and then proceeds to discuss generally the nature and distribution of the fauna of the deep sea. The abyssal region extends, according to him, from a depth of 500 or 600 fathoms to the bottom of the deepest abysses, and so far as the results of recent explorations go, there is no bathymetrical limit to the exten- sion of life downwards. At the same time, from the Challenger's dredgings it would appear that the abyssal fauna is richest between 600 and 1000 or 1200 fathoms, below which depth there is a gradual falling off, although living organisms were procured from the greatest depth at which the dredge was used. From 2000 fathoms downwards, however, the fauna usually be- comes more sparse. With regard to a matter of considerable interest, namely, the asserted absolute darkness of the abysses of the ocean, we are glad to see that Sir Wyville Thomson speaks with some reserve. He says, ‘ So far as we can judge, direct sunlight does not penetrate to great depths ; ’ and he assumes that in the case of those abyssal fishes which have greatly developed eyes, those organs have been exaggerated to catch the last feeble rays of light coming from above. The notion that deep-sea animals see by the phospho- rescent fight emitted by thousands of their neighbours, he dismisses as altogether untenable, although he believes that abyssal creatures are phos- phorescent in their native abysses, which does not appear to us to be proved. The striking uniformity of the abyssal fauna everywhere, due, of course, to the equally striking uniformity of the conditions of life, leads Sir Wyville Thomson to regard it as representing a very ancient fauna, and in this respect no doubt he is right ; but we are by no means inclined to accept the inference that therefore the present oceans are of great antiquity. Continuity of conditions in such a case does not at all of necessity imply identity of , place ; and we can quite conceive of the occurrence of an absolute continuity of abyssal conditions, without the assumption that since the close of the Palaeozoic epoch, as seems to be implied by Sir Wyville Thomson, the great oceanic depths have approximately held the same position on the surface of 52 POPULAR SCIENCE REVIEW. the earth. Geological facts seem also to stand in the way of any such assumption. As we have already stated, the present volume contains six out of the fifty memoirs in which the zoological results of the expedition are to he reported upon. There are some of the other memoirs, to the appearance of which we look forward with more interest than those here published, from the very nature of the objects to be treated of in them, such as the Corals and Hydroids, the Echinoderms, the Medusae, the Sponges, &c. ; but we can hardly hope to get more finished and complete treatises than those now before us. The first of them is by Mr. Thomas Davidson on the Brachiopoda collected during the voyage ; and when we say that it possesses all the characteristics of that gentleman’s well-known work, the reader will understand that it is a most valuable contribution to the knowledge of the class of which it treats. The number of species obtained was not very great ; indeed, Mr. Davidson seems rather disappointed that he had not more materials to work upon. There were in all 107 species, and of these comparatively few were from great depths. In his remarks on their bathymetrical distribution, Mr. David- son shows, indeed, that the Brachiopods constitute but a small element in the abyssal fauna, — 57 of the species were procured at a less depth than 100 fathoms ; and in 125 dredgings down to 600 fathoms they occurred about 25 times, while in 281 dredgings below 600 fathoms Brachiopods were brought up only 16 times. Further we find that 98 species occurred above 500 fathoms, 16 between 500 and 1000, 6 in the next 500, 4 between 1500 and 2000, and only 3 between the last-named depth and 2900 fathoms, the deepest dredging in which Brachiopoda were obtained. Many species have consider- able range in depth, the most striking in this respect being Terebratula vitrea from 5 to 1456, Terebratula Wyvillii from 1035 to 2900, and Discina atlan- tica from 600 to 2425 fathoms. Before describing the species and important varieties of Brachiopoda in the Challenger's collections, Mr. Davidson makes some general remarks on the classification of those animals, and gives a most valuable tabular list of the known recent species, showing their habitats and range in depth, and indicating the species which also occur in the fossil state. Ten species have been described as now, and these, with many of the others, are figured in four plates drawn, as usual, by Mr. Davidson himself. Prof, von Kolliker’s report upon the Pennatulida is scarcely so elaborate as the one just referred to ; but it is also of much interest from the large number of new forms which the distinguished author has had to make known. The total number of species in the collections was 38, belonging to exactly half that number of genera ; but of these, 27 species, and 7 generic types, are described as new. Further, the new types brought under his notice have induced the author to modify his classification of these Polyps (proposed in 1872), and he tabulates his new arrangement at the end of his paper.* Prof. Kolliker’s memoir is illustrated with eleven plates very nicely executed in Germany under his own superintendence. Both the figures and the descriptions relate almost entirely to the external characters of the Polyps * As this may interest some of our readers, we have reprinted it in a slightly altered form in the Scientific Summai'y. REVIEWS. 63 and their colonies, and there are very few anatomical details. As regards the geographical distribution of the group, Prof. Kolliker concludes that, so far as our present knowledge goes, the deeper portions of the oceans contain few or no Pennatulida at a certain distance from the shore. Some interesting facts have been ascertained about the geographical distribution of the families of Pennatulida, the most remarkable being the wide distribution of those curious forms the Umbelluhdae, long known as represented only by a single species from the Greenland coast. JJmbellulce have now been obtained from the temperate and equatorial Atlantic, from the ocean west of Kerguelen’s Land, from the South Polar Sea, and from the coasts of New Guinea and Japan. As regards their distribution in depth, it appears that the higher forms (Pteroeididse, Pennatulidse, Virgularidse, and Ilenillidee), live in com- paratively shallow water, only six species descending below 100 fathoms ; while the less complex types forming the other families are, for the most part, inhabitants of deep water. These simple types are probably the oldest ; and their most characteristic forms (Umbelluhdae and Protoptilidae) have been shown by the investigations of the Challenger' s naturalists to have a wide distribution. By that curious fatality in natural-history writings which so frequently makes the smallest things occupy the most space, Mr. G. S. Brady’s report on the Ostracoda is by far the largest in the present volume, and we have no doubt that Count Custracane’s account of the Diatomaceae, Mr. H. B. Brady’s report on the Foraminifera, and Prof. Hackel’s on the Badiolaria, will worthily keep up the custom. With regard to the last-mentioned group, indeed, we have heard a report that Prof. Hackel counts his species by the thousand* Mr. Brady, having to do with objects visible to the naked eye, is more moderate ; the species here described and figured by him are only 221 in number, but of these 142 are new, and three of them types of new genera. As regards the bathymetrical distribution of these little Crustaceans, we must confess to sharing the disappointment of Mr. Brady at finding that they are exceedingly rare in abyssal depths ; for when we saw the bulk of the report on Ostracoda we were in hopes that we should find described in it a host of species from great depths, such as might have acted an important part in the conversion of dead into living animal matter. But it seems that with the exception of a very few forms all the specimens submitted to Mr. Brady were obtained by dredging in comparatively shallow water or by the tow-net. From 29 dredgings below 500 fathoms only 52 species were obtained, and the number of individuals of these was but small ; whilst below 1500 fathoms 13 dredgings furnished only 19 species. Mr. Brady describes the species of the group placed under his charge in systematic order, but for the purpose of indicating their geographical distribution he divides the stations at which dredging operations were carried on, and from which Ostracoda were obtained, into seven regions, and finally tabulates all the species collected during the voyage, and indicates their distribution in the different areas. A further aid to the student in this direction is to be found in the list of localities with the species found in each, which follows immediately upon this table. Some few species are very widely distributed : thus two species of Halocypris occur in all Mr. Brady’s seven areas, whilst two species of Cythere are found respectively in five and six of them; the latter are deep- 54 POPULAR SCIENCE REVIEW. sea forms. Very few can be identified with known fossil species. The Report on the Ostracoda is magnificently illustrated with forty-four plates, the figures in which have been most beautifully executed by Mr. W. Purkiss, and an inspection of these will enable the reader to form some con- ception of the laborious and minute research that Mr. Brady must have devoted to these little carapaces. A few details of structure illustrative of generic characters are given in some of the plates, the only defect in which seems to us to be that they have no indication of the natural size of the objects, or of the magnifying power under which they have been drawn. As the figures are enlarged from 30 to 60, and sometimes 80 diameters, an inti- mation of the amount of the enlargement ought to have been given. Prof. W. Turner seems to have had some very unpromising materials in the bones of Cetacea which were handed over to him for investigation, and he has apparently made about as much of them as could well be expected. The most important specimen was a young skull of Mesoplodon Layardi from the Falkland Islands, which has enabled the author of this report to furnish some interesting details as to the formation and structure of the teeth in th's imperfectly known Cetacean. Other specimens belonging to the same species were obtained at the Cape, the Chatham Islands, Australia, and New Zealand, so that the species seems to make the circuit of the Southern Hemisphere. The skull, cervical vertebrae, and sternum of the young animal, and sections of its teeth and of those of the adult are figured. Some details of the structure of Hector’s JEpiodon chathamiensis are given, and the species is identified with Ziphius cavirostris. A great number of tympanic bullae and fragments of other bones dredged up in various localities are also described, and some of them figured. Prof. W. K. Parker contributes the first part of an elaborate memoir on the embryonic development of the Green Turtle ( Chelone viridis), in which he deals solely with the development of the cranium, face, and cranial nerves. Mr. Parker points out certain resemblances and differences between the Turtle and other Reptiles and the Batrachians, and indicates that the great number of somatomes in the neck and tail of the early embryo would seem to ‘ suggest an ancestry having a longer neck and tail than the existing forms;’ and he goes on to remark that 1 as some of the cretaceous Chelonia certainly possessed teeth, and as a few forms, both fossil and existing, have the nasal bones distinct from the prefrontals, it is evident that the modern Chelonia are forms that have become differentiated from their nearest reptilian relations by specialization. A long-necked ancestry, with a feebly deve- loped carapace, and many feeble bones of the plastron arranged triserially, would bring us very near to the Plesiosaurs.’ This report is illustrated with 15 plates. Finally, we have Dr. Gunther’s excellent report upon the Shore-fishes, in which he describes the littoral fishes collected during the voyage, with the addition of the few freshwater forms that were taken. Dr. Gunther tells us that he had 1400 specimens, representing 520 species, out of which 94 were new. He has treated the species in faunas laid down and divided upon a somewhat elaborate plan, but for the convenience of reference in determining species he has appended to his memoir a systematic list of all the species with references to the pages on which they are described or REVIEWS. 55 referred to. Of the new species a considerable number are Rays. Fourteen new genera are established, and among these forms of Pleuronectidae seem to be most numerous. The plates, thirty-two in number, illustrating this report, are most admirably executed, and display the beautiful or grotesque characters of the fishes very clearly. We have felt it a duty to enter in some detail upon the consideration of this volume as being not only in itself a repository of most valuable materials, but also, we may hope, the precursor of others, at least not less rich in interest and information. The zoological Reports of the Challenger expedition, if carried out throughout in the same spirit, will certainly bear comparison with any work of the kind. We may add that the volume is issued at a very moderate price, and that the different memoirs may be purchased separately. Also that the sale has been entrusted to several publishers in London and elsewhere. ELEMENTS OF ASTRONOMY.* THIS is one of the new volumes of Longman’s Text Books of Science adapted for the use of students, and is a work therefore which should give a full and explicit treatment of its subject, so as to enable its readers to obtain a sound knowledge of the elements of the branch of Science to expounding which it is devoted. Above all, the information it contains should be trustworthy, and carried up to recent date. It cannot be said that this volume fulfils these ends. It is a very unsatisfactory work, as nearly every section shows evidence of inexperience and want of familiarity with its subject ; all the more surprising as the work is from the pen of the Royal Astronomer for Ireland, and the head of the principal Observatory therein, that of Dunsink. The work is divided into twelve chapters and some 273 sections, each section treating of its subject in the semi-isolated form so customary in mathematical text-books in common use at the Universities. These sections are badly arranged, those devoted to analogous subjects being often widely separated ; and they are commonly devoted to the lengthy exposition of subjects which seem to indicate a strange inexperience of the requirements of astronomers. At times several pages are given up to the elaborate treatment of unimportant matters, whilst subjects of far more importance are dismissed in a few lines. Again, a subject is introduced and partially discussed, only to be taken up again and re-discussed at another time. Further, at times essential points are baldly stated and required to be taken on trust, whilst the minor points connected with them are made the subject of elaborate geometrical discussion. All these are grave faults in a work designed for students. In many instances remarkable inexperience is shown in the quotation of authorities and data, as if the author was unaware of their merits ; in many cases old and untrustworthy results are quoted, and more modem and * Elements of Astronomy. By Robert Slawell Ball, LL.D., F.R.S. Andrews Professor of Astronomy in the University of Dublin, Royal Astronomer for Ireland. 8vo. London, Longmans, 1880. 56 POPULAR SCIENCE REVIEW. accurate results ignored. Thus, on page 261 we find Schroter (Epoch, 1780- 1810) quoted as the authority as to the density and refraction of the atmosphere of Venus, whilst the author ignores the only trustworthy results, those of Madler (1840-1850), and Lyman (1865-1875), though they prove Schroter’s results to he erroneous. Again, the author (pages 183 and 290) quotes and makes use of the value of the solar parallax derived from the transit of Venus of 1874, and published in the Report of the Astronomer Royal, ordered to be printed by the House of Commons, July 6, 1877, though it is well known that this result is valueless. It has, in fact, been practically abandoned even by its author. No reference whatever is made to the later results obtained by Major Tupman, nor to that found by Mr. Stone. In the last chapter, headed ‘ Astronomical Constants,’ and occupying some ninety pages, there are innumerable cases of this inex- perience as to what are trustworthy results and what are valueless, though accuracy in these data is of the most enormous importance to students. Time after time we find a long list of old results quoted — results a few of which may possess a little interest as curiosities, though of no value to Astronomy, whilst many of the most important modern determinations, often in fact the very determination in general use, are completely ignored. Thus for the obliquity of the ecliptic the only two modern values are Leverrier and Airy, and for Precession, Struve and Leverrier ; Nutation and Aberration fare better. In the solar parallax we have Encke’s earlier result only ; Leverrier’s early result, given as derived from ‘ the parallactic equation of the Moon:’ Hansen’s earlier and erroneous value only, and Tupman and Stone from the transit of Venus; and Downing and Hall from the observation of Mars completely ignored. Eor the planets we have Leverrier’s elements given, but mostly with wrong epochs. The diameters without Young’s value for Mercury ; Plummer, Hartwig, and Auwers, for Venus; Ellery, Encke, Galle, Pritchett, for Mars, &c. For the value of the secular acceleration in the motion of the Moon we do not find either Adams or Delaunay’s latest theoretical values, nor Hansen’s last value from observa- tion ; but we do find Airy’s last value, now admitted by its author to be erroneous, and one which was generally known to be erroneous from the very day it was published. In the values for the lunar parallax we find no reference to Adams, Breen, or Hansen. For the semidiameter the only modern value is that from the eclipses of 1860 and 1870, and all unnoticed are Burckhardt’s, Plana’s, Pierce’s, Hansen’s, and the Greenwich values. Under the head of the Lunar Equator we find either the lunar crater Manilius treated as an observer of the Moon, or the lunar observer Nicollet treated as a lunar crater, or perhaps both ; and the results which Nicollet deduced from observations of the spot Manilius made by the astronomers, Arago, Bouvard, and Nicollet, are assigned first to Poisson and then to Plana. The section on the figure of the Moon is in helpless confusion, and hopelessly wrong. In the section on the Topography of the Moon, we find no reference to either Lohrmann’s important map or his sections ; and even Beer and Madler’s Der Mond is omitted, whilst Sir W. Herschel’s ‘ Astro- nomical Observations relating to the Mountains of the Moon ’ is carefully inserted. This list must be enough, and yet we have only run lightly over a third part of the ninety pages of this chapter. REVIEWS. 57 It would be impossible in tbe space of this short review to indicate more than a small fraction of the total number of imperfections which we have noticed in looking- through the volume. On page 16 we find it stated that the mirrors of reflecting telescopes are usually made of speculum metal, though of late years excellent mirrors have been made of silvered glass, whereas there has been scarcely a mirror made of speculum metal for a quarter of a century, and over ninety-nine per cent of the reflecting telescopes in use have silver-on-glass mirrors. Pages 79 to 88 are devoted to the transit instru- ment and its corrections, though the very lengthy account would be quite insufficient to enable any one to take and reduce a transit, and it contains an extraordinary definition of the error of collimation, — the axis of collimation being- defined as the line from the centre of the object-glass to the inter- section of the central cross wires ! Towards the end we have a selection of star catalogues given as the most generally useful : these are the British Association Catalogue ! Argelander ! ! and Lalande ! ! ! Not a single cata- logue from which a decent star-place could be derived, and all based on observations made near the beginning of the century ! On page 283 we are favoured with a peculiar description of the lunar mountains, and the so-called lunar craters are spoken of as the nearly extinct craters of once active volcanoes, and as being several hundred in number ! The illus- tration given as that of a typical lunar crater is curiously unlike anything on the face of the Moon. The picture of the Moon would not be so bad did not the shadows give rise to the question whether there were not two suns shining on it. The author also speaks of the absence of any penumbral fringe to the border between light and darkness on the Moon as proving the absence of any sensible atmosphere, whereas the actual existence of a broad penumbral fringe is well known to every lunar observer ; and it is also known that no possible atmosphere on the Moon would produce such a broad fringe of this nature. On pages 115-123 we find a long account of the parallel-wire position-micrometer and its use, but no account of how the position-angles are to be determined, or even what they are. Later (page 332) we are told what a position-angle is, but not in what direction it is measured, so that the earlier information is useless. On page 326 we are told that 1 it is at present, at all events, quite out of the question to suppose that a quantity so minute as the Sun’s diameter could be detected by our instruments a startling statement, followed as it is by the addition that even were it ten times as great, it would be barely appreciable. It is to be trusted that the context will show the student that this means ( if the Sun’s diameter seemed two hundred thousand times smaller than it does to us.’ The whole character of the book may be summed up as a little badly selected astronomy very diffusively treated with the aid of elementary geometry — a work neither sufficiently trustworthy nor sufficiently complete for the purpose it aims at. Its principal virtue is the clear and lucid manner in which it is written, the distinctness with which the various mathematical principles are enumerated, and the capital index with which it is furnished. As a text-book of Astronomy, however, it is certainly not to be recommended to any one wishing to obtain a full and trustworthy account of Modern Astronomy. 58 POPULAR SCIENCE REVIEW. GEOMETRY.* THIS work is intended for students wishing to gain such a knowledge of the principles of Practical Geometry as shall he useful to them in the drawing-office or the workshop. It contains under the heads of Practical Plane Geometry, and Orthographical Projection or Solid Geo- metry, numerous examples of the different problems arising in the study of geometrical drawing, the methods of solution being given with considerable detail, and very fully illustrated. Most of the cases are representative of such as have actually occurred during the author’s class-teaching, and a large number of the examples given for practice are selected from the examination papers of South Kensington and the Indian Engineer- ing College. A principal purpose of the work, as announced on the title- page, is 1 to meet the requirements of the higher stages in the Science and Art Department Syllabus,’ and this it is certainly well adapted to do, as any student who had carefully studied it might he expected to take a good position in the South-Kensington examinations. The excellence of the work for this purpose will, however, make it somewhat disappointing to those who may look into it for information on other than the simpler kind of knowledge required by elementary students ; and it may be regretted that the author has found it necessary to restrict his work so closely within the limits of the Syllabus. For example, there is practically nothing about per- spective projections, the only information given under this head being confined to a few pages on isometric projection, which is treated merely as resulting from a peculiar property of the cube, instead of being a repre- sentative, and that the least valuable one, of the class of axonometrical pro- jection, the more important monodimetric and anisometric kinds being not even mentioned by name. The statement that isometric projection is only applicable to rectangular solids is unfortunate, a3 one of the few useful appli- cations of this kind of drawing is in the delineation of the workings on mineral veins which are solids of more irregular curvature than any that it is probably ever necessary to represent in any other branch of industrial drawing. In going through a work such as the present, the question is forcibly presented as to how far the working of complex cases of oblique projection, of intersecting solids of the most irregular character, such as are presented in its pages, is necessary to make a good mechanical draughtsman. The author tells us ‘ that an ignorance of projection must be a fatal impediment to success in the workshops.’ This contrasts somewhat amusingly with the experience of one of our most scientific mechanical engineers, Prof. Fleeming Jenkins, F.R.S., who in his presidential address at Edinburgh, in 1871, speaks of 1 the little quasi mechanical drawing which is taught’ (under the Science and Art Department scheme) ‘ as mostly mere geo- metrical projection, a subject of which real draughtsmen very frequently, and with little loss to themselves, are profoundly ignorant. Descriptive * Practical Plane Geometry and Projection. By Henry Angel. 8vo, with 4to Atlas of Plates. Wm. Collins, Sons, and Co. (Limited.) London and Glasgow. 1880. REVIEWS. 59 geometry and geometrical projection are nearly useless branches of the art, and the little encouragement that is given is almost monopolised by them.’ In many, probably in most cases, time might be more usefully spent in making measured drawings from actual working objects, when once the elements of plane geometry have been mastered, than in solving the most ingeniously contrived examination puzzles in projections. This view of the subject appears to prevail in France, judging from the albums exhibited at the late Universal Exhibition, containing drawings made in the schools attached to the larger collieries, smelting and mechanical engineering works. There the works done by children from about twelve years of age upwards were for the most part representations of objects in common use in the works, from the simplest elements to tolerably complicated combinations, such as small steam-engines or simple tools, but in all cases the drawings were made from the real objects. BELFAST LOUGH.* A BOOK on the natural history of Belfast by a Robert Patterson, and dedicated to the memory of Robert Patterson, ought to be of interest to naturalists ; and the volume before us on the Birds, Fishes, and Cetaceans frequenting the fine inlet of the sea which bears the name of Belfast Lough, will interest many readers. Mr. Patterson, indeed, does not pretend to be writing a profound scientific work : his work contains observa- tions on the habits of the inhabitants of the Lough, made by him during the excursions of many years, and deals rather with the habits and manners of the animals referred to than with their description and classification. It is, in fact, especially as regards the Birds, a very pleasant, semipopular treatise, which may be perused with both entertainment and profit by the i general reader, while at the same time, like so many other local books, it contains numerous bits of information which will make it welcome to the Naturalist. The statements as to fishing in the Lough are of much interest. NORTH AMERICAN SEALS. t JUST three years ago (P. S. R. January, 1878, p. 81) we called attention to the publication of Dr. Elliott Coues’ monograph of North- American Mustelidse ; Mr. Allen’s work on the Pinnipedia is a still more elaborate and valuable production. Seals, from their very nature, have, in many * The Birds, Fishes, and Cetacea, commonly frequenting Belfast Lough. By Robert Lloyd Patterson. 8vo. London : D. Bogue, 1880. t History of North American Pinnipeds, a Monograph of the Walruses, Sea-Lions, Sea-Bears, and Seals of North Amenca. By Joel Asaph Allen. — U.S. Geological and Geographical Survey of the Territories, Miscellaneous Publications, No. XII. 8vo. Washington : * Government Printing Office, 60 POPULAR SCIENCE REVIEW. cases, a far wider distribution than can generally be enjoyed by terrestrial mammals ; and hence Mr. Allen’s investigations, although specially directed to the species inhabiting the shores of North America, necessarily range over a far more extended field, and deal with forms in which European naturalists have a direct local interest. Moreover, in discussing systematic points, questions of nomenclature, &c., our author does not confine himself to the species with which he has specially to deal, but treats of the group generally, referring also to the habits and natural history of species from all parts of the world, and thus his book is rendered indispensably necessary to every student of the Pinnipedia. In the classification of the Pinnipeds the author introduces one new feature : he divides the sub-order into two great tribes, — one including the Eared Seals and Walruses, which have their hind feet turned forwards and walk upon all fours, which he calls Gressigrada ; the other for the reception of the ordinary seals, which progress on land by the action of their fore- paws alone, assisted by wriggling motions of the body, and these are accord- ingly named Reptigrada. The groups seem to be natural enough, but we don’t admire their names. At the outset the reader is somewhat startled at missing the old familiar name of Tnchechus for the Walrus, and finding substituted for it the very unfamiliar one of Odobcenus. There is no doubt that it was by an incon- ceivable series of blunders that Linnaeus, in the last edition of his Sy sterna Natures, transferred the Walrus to the genus Trichechus, which belongs of right to the Manatee ; but we question whether under the circumstances it was worth while to disturb the existing nomenclature. Mr. Allen dis- tinguishes two species of Walrus, — the Atlantic Walrus ( Odobcenus ro&mai'us ) and the Pacific Walrus (O. obesus ), — and a very full account is given of their characters and natural history. Copies of the very curious old figures of the Walrus, taken from the late Dr. Gray’s paper in the Pro- ceedings of the Zoological Society (1853), show rather amusingly how very far the vivid imaginations of travellers and naturalists could carry them. Mr. Allen discusses at considerable length the difficult question of the species of Eared Seals (Otariidae), and comes to the conclusion that all the known forms may be referred to nine species, — five of which are Hairy Seals, or Sea-Lions (forming the sub-family, Trichophocaceae), and four of them Fur Seals, or Sea Bears (Ouliphocaceae). The general natural history of these animals is given in some detail, with a tabular synopsis of the genera and species, and the three species (two Sea Lions and one Sea Bear) which inhabit the Pacific coast of North America, are fully described from all points of view. The Earless Seals (Reptigrada) form the single family Phocidse, of which seventeen species are here catalogued by Mr. Allen, eight of them being fully described as inhabitants of North America. Besides these a ninth, somewhat doubtful species is noted as an inhabitant of the West Indies, and an occasional visitor to the southern shores of the United States. This seal ( Monachus ? tropicalis) appears to be known to the author chiefly from the descriptions of Hill and Gosse, who observed it in Jamaica. Here, as indeed throughout the book, Mr. Allen has devoted the most unwearied labour to the accumulation of reliable information, not only with REVIEWS. 61 regard to the North American species, which may be considered the special objects of his study, hut also in connexion with those which do not reside on the North American coasts, so that his work contains a summary of our present knowledge of the geographical distribution, habits, and synonymy of the living Pinnipeds, with most valuable notes upon the fossil forms which have been discovered in various parts of the world. The sections of the work dealing with the natural history of the Seals will be found most interesting, although, we believe, that most readers will feel their indignation rise at the descriptions of the proceedings of the seal-hunters, whose reckless destruction of unnecessary multitudes of these unfortunate creatures bids fair to extir- pate some of them, at any rate, from the face of the earth. We had marked two or three passages for quotation, in order to show the extent to which these horrible massacres, sometimes attended with the grossest cruelty, have reduced the seal population of the Northern seas ; but this notice has already reached too great a length. We can only express a hope that those who have power in their hands may, if possible, find some means of putting a restraint upon the operations of the sealers. Independently of the cruelty of such indiscriminate massacres as are to be found described in Mr. Allen’s pages, and the loss to the world caused by the reckless destruction of seals which has so long prevailed, the unfortunate inhabitants of the Arctic shores, who are mainly dependent upon seal’s flesh for their food, are rapidly diminishing in number owing to the increasing scarcity of this article of diet, and unless some change is made many tribes will perish off the face of the earth. INFUSORIA.* THE appearance of this book promises to mark an epoch in the history of our knowledge of the Infusoria perhaps of more importance than any that have been made since the publication of the great work of Ehrenberg. Of course, as only one part of it is published, and this deals solely with the generalities of the subject, it is at present impossible to contrast the systematic work with that of Ehrenberg, or of any subsequent writer ; but there are, even in this portion, sufficient evidences of careful, painstaking, and thoroughgoing work, to lead us confidently to expect that the descriptive section, when it appears, will also be of very high quality. In the part now before us, Mr. Saville Kent opens with an historical sketch of the progress of the knowledge of the Infusoria, since the first discovered members of the class struck the startled vision of old Leeuwen- hoek some two hundred years ago. His references to the principal authors are arranged in chronological order, and he indicates the characteristics of the work done by each of them, and the effects produced by their respective labours, especially upon the scientific conception of these microscopic creatures. * A Manual of the Infusona, including a Description of the Flagel- late , Ciliate, and Tentaculiferous Protozoa, British and Foreign, and an Account of the Organization and Affinities of the Sponges. By W. Saville Kent, F.L.S., See. Part I. Super royal Bvo. London, David Bogue, 1880. 62 POPULAR SCIENCE REVIEW. A second chapter treats of the sub-kingdom Protozoa, and the position to be assigned in its ranks to the Infusoria. Our author accepts the sub-kingdom Protozoa in the old, that is to say, the pre-Hackelian sense, in- cluding the Sponges, and altogether rejecting the ‘ kingdom ’ Protista. He defines the group i as embracing all those forms of life referable to the lowest grade of the animal kingdom, whose members are for the most part represented by organisms possessing the histologic value only of a single cell, or of a congeries or colonial aggregation of similar independent uni- cellular beings.’ His views of the classification of the Protozoa appear at first sight a little complicated, inasmuch as some of his primary sections overlap one another in the classes, or at least in the class Flagellata, which includes representatives of three primary sections, so that at present it is not very clear what classificational value is to be ascribed to the latter, although one can see the interest attaching, from a philosophical point of view, to the recognition of the peculiarities embodied in them. Thus, Mr. Kent, in establishing his primary groups, has regard, i not so much to the varied character of the locomotive or prehensile appendages posssessed by the representatives of this sub-kingdom, as to the nature of the oral apparatus or systems subordinated to the function offfood-ingestion.’ In the first and lowest of these sections food is 1 incepted indifferently at any point of the periphery or general surface of the body these are called Pantostomata , and the Rhizopods may be taken as typical examples of them, although sundry flagellate Infusoria are included in the group. In the second section, although there is no true mouth, the inception of food is performed by a discoidal area occupying the anterior extremity of the body ; these are the Discostomata, and they are represented by the collared flagellate forms and by the sponges. The Eustomata have a true mouth, and are best represented by the ciliated Infusoria; whilst the Polystomata include only the ten- taculiferous forms, such as Acineta. The four classes of Protozoa, however, are characterized by their locomotive or prehensile arrangements, — they are the Rhizopoda, Flagellata, Ciliata, and Tentaculifera. With the first- named class the present work has nothing to do ; the others will be treated in detail, and we have in this first part the general description of the structural and physiological characters presented by them. As may be seen from a previous quotation, Mr. Saville Kent accepts un- conditionally the view of the unicellular nature of the Infusoria; but simple as this makes them out to be, he finds a good deal to tell his readers about their structure and the functions of the comparatively few parts of which they consist. Throughout the section of his work dealing with the mor- phology of the Infusoria, we find him making full use of the results arrived at by previous observers, but these are checked in all cases by his own researches, which have been pursued most industriously for many years. The same thoroughness of treatment characterizes the exceedingly interest- ing section devoted to the consideration of the reproductive phenomena of these little creatures, and the important chapter in which the question of spontaneous generation is discussed. Here the author again adopts the historical mode of treatment ; and, commencing with the results of the earlier observers, works up through the investigations of Pouchet and Pasteur in France, and of Bastian and Tyndall in England, to those of Dallinger and REVIEWS. 63 Drysdale, and to his own researches upon the animalcules of hay-infusions, which in combination furnish a body of evidence against which the ad- vocates of abiogenesis will find it vain to contend. Mr. Kent further treats of the zoological affinities and distribution of the Infusoria, and gives directions as to the best modes of investigating and preserving them for examination. The Sponges, as already stated, are placed by the author among his flagellate Protozoa as an order standing next to the collared Flagellata. He proposes to discuss in detail the much-vexed question of the true position of those remarkable animals, but in this first part of his book he only commences the chapter dealing with it. The chief reason assigned by Prof. Hackel for transferring the Sponges from the Protozoa to the Metazoa was derived, as is well known, from their mode of reproduction, the * swarm-gemmules,’ or ciliated reproductive bodies of the Sponges being developed according to him in the same fashion as the embryos of the higher animal forms. Hackel’s results have not passed entirely without contra- diction, and Mr. Kent declares that the developmental phenomena of the Sponges 1 accord essentially and entirely with those presented by the typical Protozoa,’ and ( that there is no formation of a germinal layer or true tissue structure in any period of their development.’ In his next part the author will expound his views of sponge-nature in full detail ; and he has already published in anticipation two plates illustrative of the structure and development of Sponges. The remaining seven plates are devoted to the illustration of the collared Flagellata, and the figures, like all those produced by the author’s pencil, are exceedingly delicate and beautiful. If carried out in the spirit in which it has been commenced, Mr. Saville Kent’s Manual of the Infusoria will certainly be one of the most important books that we possess upon the subject of which it treats — a subject of interest to all philosophical naturalists, and of special interest to all the numerous workers with the microscope. It is to be published in six parts, and in the matter of execution, both as to text and illustrations, really leaves scarcely anything to be desired. While this notice was passing through the press we received the second part of this book, but unfortunately too late to allow us to say anything about it. THE ATOMIC THEORY* SINCE the early days of Greek philosophy, the hypothesis of the atomic constitution of matter has played no insignificant part in the history of physical science. It was not, however, until the beginning of the present century that the hypothesis took so definite a shape as to become an almost indispensable aid to scientific thought. To the genius of John Dalton un- questionably belongs the credit of having elaborated the old idea with such rare subtlety that the hypothesis has been elevated to the rank of a great * The Atomic Theory. By Ad. Wurtz. Translated by E. Clemenshaw, M.A. 8vo. London : Kegan Paul & Co. 1880. 64 POPULAR SCIENCE REVIEW. theory. Prof. Wurtz, who startled us some years ago by asserting that chemistry is essentially a French science, is an ardent admirer of the theory which the English philosopher developed, and has written upon this subject a valuable work, which forms one of the recent volumes of the International Scientific Series. To say that the work has been admirably written is only to say what might be expected of anything that comes from the pen of so accomplished an author. Moreover, it is, on the whole, tolerably impartial, though we are inclined to think that the important work of Avogadro was deserving of fuller recognition. M. Wurtz’s book falls into two parts — the first dealing with Atoms, and the second with Atomicity : the latter, how- ever, is not treated so comprehensively as the former subject. After carefully looking through the book, we are unable to say where else, in the English lan- guage, the student will find so complete an exposition of the atomic theory in its bearings upon modern chemistry. It is a pleasure to add that the translator has rendered his author into admirable English. MEMOIR OF A YOUNG CHEMIST. 1 T'TTHOM the gods love die young/ The death of Thomas Wills, at the ▼ V early age of twenty-eight, furnishes another illustration of this adage. Singularly amiable as a Christian gentleman, and highly accomplished as a chemical lecturer, Mr. Wills was esteemed and beloved by all who knew him. The work that he accomplished in his brief life was not only highly creditable in itself, but gave fair promise of a brilliant future. Mr. Wills was, originally, assistant to Dr. Odling at the Royal Institution, and after- wards became Demonstrator in Chemistry at the Royal Naval College. To reproduce his papers, as has been done in this work, was a fit tribute to his memory ; but to write a biography of one who had so short a career was a matter of questionable expediency. However interesting the anecdotes of childhood may be to the family of the deceased, they are apt, in many cases, to give rise to a smile when read by a stranger. Nevertheless, we sympa- thize with the spirit in which the little volume has been written. The tenderness of a mother breathes warmly through every page, and the critic stands disarmed. A SIMPLE BOOK ON HEAT. rpiIIS is an unpretending little work, put forth for the purpose of ex- J- pounding, in simple style, the phenomena and laws of Heat. No strength is vainly spent in endeavouring to present a mathematical view of the subject. The author passes over the ordinary range of matter to be found in most elementary treatises on heat, and enlarges upon the applica- * The Life of Thomas Wills, F.C.S. By his Mother Mary Wills Phillips, and her friend J. Luke. 8vo. London; James Nisbet & Co. 1880. t A Simple Treatise on Heat. By W. Mattieu Williams, F.R.A.S., &c. With 26 illustrations. 8vo. London : Chatto & Windus. 1880. REVIEWS. 65 tions of the principles of his science — a subject which is naturally attractive to the uninitiated. Mr. Williams’s object has been well carried out, and his little book may be recommended to those who care to study this interesting branch of physics. ELEMENTARY CHEMISTRY .* DR. KEMSHEAD’S elementary work on Inorganic Chemistry was originally written for the use of students preparing for the May examination of the Science and Art Department. That it has well served its purpose is apparent from the fact that it has now reached its second edition and twentieth thousand. When it first appeared it was notable as one of the earliest text-books in which Dr. Frankland’s notation was adopted. The new edition has been corrected where necessary to bring it into accordance with the recent progress of chemistry. TABLES FOR ANALYSIS.! IT is not a very ambitious chemical feat to analyse, qualitatively, a simple salt. Mr. Yinter is teacher at the Leys School in Cambridge, where the pupils generally. cannot spend, we are sorry to hear, more than one hour a-week in the work of the laboratory. As a guide to the method of ex- amining a simple salt he has prepared these tables, which for the last four years he has found useful in his own class. They appear to be clear, concise, and accurate ; and may therefore usefully serve the purpose for which they are sent forth. THE GARDENS OF THE SUN.! ril HE GARDENS OF THE SUN is the somewhat fanciful name con- -L ferred by Mr. Burbidge upon the islands of the Malayan Archipelago, in some of which he passed some time collecting plants for Messrs. Yeitch. Of their beauty he speaks in the most enthusiastic terms ; and although in this respect he may be regarded as only confirming the statements of earlier writers, his account of his individual impressions is of interest, and may serve to give a new colour to the notions entertained by his readers. * Inorganic Chemistry. By Dr. W. B. Kemshead, F.C.S., &c. Twentieth thousand, revised and corrected. 8vo. London & Glasgow : W. Collins, Sons, & Co. t Tables for the Analysis of a Simple Salt, for use in School Laboratories. By A. Yinter, M. A. 8vo. London : Longmans & Co. 1880. X The Gardens of the Sun; or, a Naturalist' s Journal in the Mountains and in the Forests and Swamps of Borneo, and the Sulu Archipelago. By F. W. Burbidge. 8vo. London : John Murray. 1880. NEW SERIES, VOL. V. NO. XVII. F 66 POPULAR SCIENCE REVIEW. Mr. Burbidge gives a cheerful description of his voyage to Singapore, and of his experiences in that colony, including a visit to the neighbouring rajahdom of Johore ; thence he proceeded to Borneo, and afterwards to the Sulu Islands and back ; and everywhere he seems to have cast in his lot with the people in a hearty manner, which gave him many opportunities of observing their habits and modes of life. Accordingly the reader will find in this book many exceedingly interesting details with regard to the social condition of the inhabitants of the islands visited ; whilst from the circumstance that, in Borneo especially, the author made long journeys into the interior of the country, he is enabled to give much information upon the inland tribes, which will be of value to the ethnologist. He notices the Jakuns, or wild men of the interior of Johore (chiefly from the statements of Dr. Maclay), and the Muruts, Kadjans, and other supposed aboriginal inhabitants of Borneo, who seem to have disappeared from the coast, or been absorbed by the Malays, whose characters are more or less evidently modified by the intermixture of native blood. Naturally the plants of the localities visited by Mr. Burbidge attracted the greatest share of his attention ; and in collecting these he appears to have been exceedingly energetic and successful. From the mountain of Knia Balu (the Chinese Widow mountain) he succeeded in sending living plants of the gigantic pitcher-plant Nepenthes Rajah, and also another very curious species of the same genus (N. bicalearata ), in which the pitchers are armed with two formidable spines, which the author believes to have the function of preventing insectivorous birds and mammals frcm reaching the insects always contained in those curious receptacles. Fifty species of ferns, about one quarter cf which were previously unknown, were added by the author to the flora of Borneo ; and in the Sulu islands he also collected a considerable number of plants of the same order. Lists of these, with short descriptions of most of the new species, are given in an appendix. Plants did not, however, engage the whole attention of Mr. Burbidge, and many remarks upon animals observed are scattered through his pages. Nevertheless, zoology is not his strong point. Birds seem to have attracted him most, and he made collections of them both in Borneo and the Sulu Archipelago. Lists of the species obtained, with descriptions of some new forms, from the pen of Mr. Bowdler Sharpe, will also be found in the appendix. THE POETRY OF ASTRONOMY.* UNDER this title Mr. Proctor has issued another selection of his numerous contributions to our magazines during the last five or six years. Like all of Mr. Proctor’s essays, these are well-written sketches of the more popular portions of the science of Astronomy ; and if they will seem somewhat superficial to the more scientific of his readers, * The Poetry of Astronomy : a senes of familiar Essays on the Heavenly Bodies. By Richard A. Proctor, B.A., F.R.A.S. 8vo. London : Smith, Elder, and Co. 1881. REVIEWS. 67 they will prove decidedly interesting and instructive to the larger class whom Mr. Proctor more especially addresses, and who have so repeatedly shown how much interest they take in Mr. Proctor’s ingenious speculations. The contents of the volume are separately entitled : 1 Age of the Sun and Earth ; ’ ‘ The Sun in his Glory ; ’ 1 When the Sea was Young ; ’ ‘Is the Moon Dead ?’ ‘ The Moon’s Myriad Small Craters ;’ ‘A New Crater on the Moon;’ ‘ A Fiery World ; ’ ‘ The Planet of War;’ ‘Living in Dread and Terror ; ’ ‘ A Ping of Worlds ‘ Earth-born Meteorites; ’ and the ‘ Architec- ture of the Universe.’ Of these essays, the one we like best is that called, ‘ The Sun in his Glory.’ The weakest one is that on 1 The Moon’s Myriad Small Craters,’ because it is founded on a very imperfect acquaintance with the real nature of the lunar surface and especially of these very formations — small craters — to which he refers. Had they been of the nature supposed by Mr. Proctor, his extraordinary theory, that they are indentations of the surface due to the impact of large meteors, might be made to read plausible enough, but then they are not of the nature supposed, which is unfortunate for the theory, — or the Moon. Strangely enough, Mr. Proctor selects Prof. Newcomb as his authority for the nature of the lunar surface ; though eminent as Prof. Newcomb is in his own departments of Astronomy, his acquaintance with the character of the Moon’s surface is necessarily extremely superficial. Mr . Proctor’s best essay, entitled ‘ A New Crater on the Moon,’ illustrates one of the evils of this system of reprint essays; for however permissible it may have been at the time of writing, it is now known to be founded on a mis- take as to the identity of the crater supposed to be new, and states as facts things now known to be quite erroneous. The two essays on the planet Mars will be found most interesting to the general run of readers, as they contain some very ingenious speculations. > I 68 SCIENTIFIC SUMMARY. ASTEONOMY. The Secular Acceleration in the Mean Motion of the Moon. — In tlie Astronomical Summary of the last number of this Revieio, reference was made to a paper by Sir G. Airy on this subject, in which he arrived at results con- tradictory to those which had been admitted to be correct by all the great mathematicians of the day. At the same time it was pointed out that the result obtained by the Astronomer Koyal was unquestionably erroneous, his investigations being vitiated by fundamental errors. The supplementary number of the Monthly Notices of the Royal Astronomical Society contains a further paper by Sir G. Airy, in which, by rectifying most of these errors, he arrives at the same result as that found by Prof. Adams, and which has been now admitted to be correct for nearly twenty years. Curiously enough, Sir G. Airy, in his last paper, does not acknowledge his error, except implicitly by giving results diametrically opposed to those of the previous paper. Nautical Almanac for 1884. — This volume has been just published. Like the preceding volume, the places of the Moon have been derived from Hansen’s Table with the addition of the empirical corrections deduced by Prof. Newcomb, and published in 1878. There may be some doubt as to the advisability of introducing these empirical corrections, for they have already commenced to deviate from observation. Jupiter. — During the autumn the planet Jupiter has been giving evidence of considerable activity, and a large number of interesting observations have been made.* The famous red spot has faded in colour, and is no longer so vivid as during last year, though it is practically as large and as conspicuous. Quite lately, however, it has shown traces of a woolly texture, not improbably the incipient signs of its gradual disappearance. Prof. Julius F. Schmidt, of Athens, has carefully discussed the observations of the time of transit of this spot across the apparent central meridian of the planet, with the view of determining the time of rotation. From the observations made during 1870, he obtains the value — 9h 55m 348-42 for the time of rotation, and from the observations made during 1880 he finds the value — 9h 55m 348,43 * See also an article by Mr. W. F. Denning in the present number. SCIENTIFIC SUMMARY. 69 This coincidence is interesting, as last year it was thought that the motion of the red spot was gradually accelerating. From the total number of observations he derives the value- 9h 55m 34s,42 ± 0S*04 This value differs by 8s- 7 from the result of the observations of the rotation of Jupiter made during 1862, when from the observation of a very permanent white spot there was derived the value 9h 55m 25s*68 ± 0ST8 Of late a considerable number of white spots have made their appearance on the dark red equatorial belt. Some of them are beautifully round, and resemble satellites in transit, but others are more irregular, and have a woollier aspect. These white spots move considerably faster than the red spot, every day showing a marked gain. According to Schmidt, the time of revolution of these white spots is 9h 50m 09 So that they gain thirteen minutes per day on the red spot. This is con- firmed by the results obtained by Mr. W. F. Denning, who finds the time of rotation of three of these spots to be 9h 50m 5s, 9h 50m 6s, and 9h 50™ 3s respectively. Towards the middle of October a number of round dark spots, at times almost black, made their appearance in the northern hemisphere of the planet. These spots greatly increased in number, and towards the end of November they formed, according to Mr. W. H. M. Christie, a regular dark belt. From the observations of Messrs. Williams, Eiger, and Denning, they seem to move with the same velocity as the equatorial white spots, having a time of rotation of 9h 50m 5s. According to Prof. Schmidt, however, some of the black spots move slower than' the white equatorial spots. Following the red spot there is a pale greyish spot, and also a whitish streak ; both these seem to move with the same velocity as the red spot itself, so that it would seem that the variation in velocity affects the different belts as a whole. At the present time, therefore, Jupiter presents an interesting subject for critical examination with large instruments, and a good deal may be expected to be learned when all the recent observations are critically discussed. Hartwig's Comet. — This comet was discovered by Herr Hartwig at the Strasburg Observatory, on the evening of September 19, 1880, and by Prof. Harrington at the Ann Arbor Observatory on the following night. It was a bright comet, of considerable size, and for several days during the be- ginning of the month could be easily seen with the naked eye, being a little brighter than the well-known nebula in Andromeda. It was not discovered until more than three weeks after its perihelion passage, so that when seen it was quickly receding from the Earth, thus rapidly becoming fainter, and by the end of the month it had become so faint that it could only be seen in the most powerful telescopes. It was a bright diffuse comet, with a rounded nucleus, and a tail nearly two degrees in length. Shortly after its discovery, Prof. Winnecke pointed out the strong resemblance between its orbit and that of the bright comet of 1506, and 70 POPULAR SCIENCE REVIEW. expressed the opinion that the two were probably identical. Later in- vestigations confirmed this view, and showed that the comet strongly resembled in its orbit the comet visible in the years 1444 and 1569. It would therefore appear to have a period of some sixty-two years. Dr. Schur and Herr Hartwig, from their investigations, assign to the comet a period of 62£ years, and the following elements : Perihelion passage, 1880, September 6 Longitude of perihelion Longitude of ascending node Inclination of orbit Eccentricity of orbit . Semi-axis major .... 5894, Berlin mean time. . 83° 33' 28" . 44 33 30 .38 8 56 . 0-97764 . 1-5756 The o^bit of the comet extends, therefore, beyond the orbit of the planet Neptune ; but owing to the great inclination of the orbit, it cannot be much affected by the perturbation of any of the greater planets. The comet, however, approaches very close to the orbit of the planet Mercury at the ascending node; and Prof. Winnecke is of opinion that it may be due to the attraction of this planet that the comet has been introduced into the solar system with its present elliptical orbit. For though at present the orbits do not approach each other sufficiently near to enable the planet to very importantly affect the motion of the comet, at some past period the two orbits may have been nearly coincident, though now separated by the effect of perturbation. Swift's Comet. — On Monday, October 11, 1880, Prof. Lewis Swift, of Rochester, New York, discovered a large comet in the constellation Pegasus, but no observation seems to have been obtained during the month in Europe. On November 7, 1880, a bright comet was discovered at Dun Echt Observatory, belonging to Lord Lindsay. A day or two showed that the two comets were identical, and revealed in the constellation Lacerta that the orbit of the new comet coincided very closely with that of Comet 1869. This comet was discovered by Herr Temple, on November 27, 1869, in the constellation Pegasus a few days after its perihelion passage, and it was last seen at Leipzig on December 31st. On November 29, 1869, it was described by Dr. Vogel as a very faint object of considerable dimen- sions, being nearly 6' in diameter. From observations spread over a month, Dr. Bruhns calculated a parabolic orbit, whose elements he found to be — Perihelion passage, 1869, November 20-854, Berlin mean time. Longitude of perihelion . . . .41° 17' 13" Longitude of ascending node . . . 292 40 29 Inclination of orbit . . . . . 6 55 0 Perihelion distance 1*1026 Dr. Bruhns remarked, however, that this orbit did not closely represent the observations, and seems almost to have suspected the elliptical character of the orbit. The close resemblance between this orbit and that calculated from the observations made of the comet of 1880 is shown by the elements for the latter comet calculated by MM. Zelbr and Hepperger : — SCIENTIFIC SUMMARY. 71 Perihelion passage, 1880, November 8*32198 Longitude of perihelion . . 42° T 4" Longitude of ascending node 295 36 54 Inclination of orbit . . 7 22 5 Perihelion distance . . 1*1019 There can be little doubt, therefore, about the identity of the two comets, so that it would give the comet a period of a little less than eleven years. This would give — Eccentricity of orbit . . . = 0*7767 Semi-axis major . . . . = 4*9352 The orbit of the comet would approach, therefore, very close to the orbit of the planet Mars, and, what is of still more importance, within 0*5 of the Earth’s mean distance of the orbit of the planet Jupiter , and not very far from the orbit of Saturn. Erom its mean approach to the orbit of Jupiter, and from the near commensurability between their periods of revolution, this great planet will produce very considerable perturbation in the motion of the comet. Faye’s Comet. — Since its discovery by Mr. A. A. Common, with his 37-inch reflector, at Ealing, this comet has been observed by Prof. Temple at Arcetri, by Dr. Duner at Lund, Dr. Pechiile at Copenhagen, and Herr Yon Konkoly at O’Gyalla. The observed place corresponds very closely to the Ephemeris, and so affords a striking confirmation of the accuracy of the researches of Prof. Axel Moller. It is a very faint object, and scarcely within the reach of telescopes of ordinary aperture. BOTANY. Growth of Plants. — On December 16, Mr. Francis Darwin read, before the Linnean Society, two important papers, one on ‘ The power possessed by leaves of placing themselves at right angles to incident light,’ the other en- titled 1 The theory of the growth of cuttings, illustrated by observations on the Bramble, Rubus fruticosus ; ’ two papers which, though relating to different questions in the physiology of plants, have nevertheless much in common. Both of them bear on the relationship between the external and internal conditions of life ; between external forces, such as light and gravitation, and the constitution of the organisms on which these forces act ; and both tend to show the importance of recognizing in plants those specific forms of sensitiveness which may be said to determine the results which will follow external changes. We have to thank Mr. Francis Darwin and the authorities of the Linnean Society for the following abstract of these papers : — I. The behaviour of leaves in relation to light may be illustrated by the cotyledons of a seedling radish; if it is illuminated from above, the coty- ledons are extended horizontally, and are thus at right angles to the direc- tion of incident light. If the seedling is then placed at a window, so that it is lighted obliquely from above, and if the stem (hypocotyl) is prevented 72 POPULAR SCIENCE REVIEW. from bending* * * §, the cotyledons will accommodate themselves to the changed conditions by movements in a vertical plane. The cotyledon which points towards the light will sink, while the other will rise ; and thus both will become once more at right angles to the incident light. Two theories have been proposed to account for this property of leaves. The first is that of Frank,* who ascribes to leaves, and to some other organs, a specific sensitiveness to light, called ‘ Transversal-heliotropismus,’ or ‘ dia- heliotropism.’ t Just as an ordinary heliotropic organ has an inherent tendency to become parallel to incident light, so a diaheliotropic organ has an inherent tendency to place itself at right angles to the direction of the light. The two classes of organs differ from each other exactly as some creeping rhizomes do from ordinary stems ; the rhizome tends to extend itself horizon- tally under ground, while the stem above the surface grows vertically upwards. J A different theory has been proposed by De Vries, § whose views are supported by Sachs, || with additions or modifications. According to these views it is not necessary to assume the existence of any special kinds of heliotropism, since the phenomena might result from the ordinary forms of heliotropism and geotropism acting in concert. Thus, in the case of the seedling radish illuminated from above, if the cotyledons are apheliotropic (negatively heliotropic) and apogeotropic (negatively geotropic), it is possible that they might be kept in equilibrium by these opposing tendencies. The tendency to move away from a vertical light will make the cotyledons curve downwards toward the earth, and the apogeotropism, or tendency to move awav from the centre of the earth, may exactly balance the down- ward tendency, so that the cotyledons remain horizontal. Besides the various geotropic and heliotropic tendencies, there are other modes of growth which may enter into the combination. In some cases there is a natural preponderance of longitudinal tension and growth along the upper surface of the petiole, so that, owing to impulses arising within the plant, there is a tendency for the leaf to curve downwards;^! this tendency is called longi- tudinal epinasty, or simply epinasty : the opposite tendency is called hypo- nasty. According to the theories of De Vries and Sachs, epinasty may be opposed by heliotropism, or by apogeotropism and geotropism, and all these opposing forces may combine in producing an equilibrium. The object of the present paper is to test the relative values of the two above described theories, — that of Frank and that of De Vries and Sachs. The method employed was to fix the plants under observation to a hori- zontal spindle, which was kept in slow rotation by clockwork. This instru- ment (called the ‘ clinostat ’) has been employed by Sachs for the study of ordinary heliotropism ; light is admitted parallel to the axis of rotation, and * Die natiirliche wagerechte Richtung von PJlanzentheilen, 1870. t Darwin, Power of Movement in Plants ,’ p. 438. t See 1 Elfring,’ in Sachs’ Arbeiten, 1879. § Sachs’ Arbeiten, i., 1872. || Sachs’ Arbeiten , ii., 1879. IT Or more accurately, in the direction in which the morphological lower side of the petiole is directed. SCIENTIFIC SUMMARY. 73 tlie plants are thus subjected to a constant lateral illumination, while they are freed from the disturbing influence of gravitation ; for, owing to their being kept in constant slow rotation, there is no reason why they should bend geotropically in one direction more than another.* On the same principle the behaviour of leaves which place themselves at right angles to the incident light has been studied. If a plant with horizontally extended leaves which has been illuminated from above, is fixed on a slowly revolving horizontal spindle, so that the axis of the plant is parallel both to the axis of rotation and to the direction of incident light, we shall have a means of testing the opposing theories above mentioned. The plant’s leaves will still be illumi- nated by light striking them at right angles ; therefore if Frank’s theory is the right one, they ought to remain in this position. But if De Vries and Sachs are correct in their views, the leaves ought not to be able to remain at right angles to the incident light since geotropism has disappeared, which was one of the tendencies necessary to keep the leaves in a position of equilibrium. A considerable number of experiments were made with the celandine {Ranun- culus ficaria) , the results of which are decidedly in favour of Frank’s views. The leaves of the celandine are sometimes extremely epinastic, so that they press against the ground ; and when a plant is dug up it often happens that the leaves, being released from the resistance of the soil, curve nearly verti- cally downwards. If such a plant is fixed on the clinostat in the position above described, the leaves will be pointing away from the light, so that if the leaves were apheliotropic, as might be expected according to De Vries’ theory, the leaves would remain pointing away from the window. But this is not the case ; they move forward until they are approximately at right angles to the fight, and then come to rest. Again, if a celandine is placed in the dark, its leaves rise up so as to be highly inclined above the horizon ; if the plant is then placed on the clinostat, the leaves (which now of course point towards the light) again accommodate themselves by curving back- wards until they are at right angles to the light. Thus the leaves cannot be called heliotropic, or apheliotropic ; we are forced to believe that under the influence of light they are able to move in either direction which may be necessary to bring them at right angles to the light. The other experiments with R. Jicaria, the details of which we omit, lead to the same general result. Besides a few observations on Vida, Cucurbit a, and Plantago, a series of experiments were made on seedling cherries, and these lead to a somewhat different result. A cherry-plant, growing in the open air, has its leaves approximately horizontal, and when placed on the clinostat, as above described, the leaves are unable to remain at right angles to the light, but curve back- wards, so as to become parallel to the stem of the plant. The petioles are shown not to be apheliotropic but to be powerfully epinastic, so that they move in the manner described when unopposed by apogeotropism. It is clear, therefore, that the horizontal position of the leaves of seedling cherries growing normally, must largely depend on the balance struck be- tween epinasty and apogeotropism, in accordance with the views of De Vries and Sachs. But since these forces obviously cannot produce the power of accommodating itself to the direction of incident fight which the cherry See Sachs in his Arbeiten, Bd. ii., 1879. 74 POPULAR SCIENCE REVIEW. possesses, we must assume that some kind of heliotropism enters into the combination. The view to which the present research lends most probability is, that dia- heliotropism (transverse-heliotropism) is the really important influence at work. In the case of the celandine we have seen that the sensitiveness to light is strong enough to determine the position of the leaves, although the natural balance is disturbed by the annihilation of geotropism. It seems probable that an essentially similar state of things holds good in the case of the cherry. When the plant is growing normally, it trusts to epinasty and apogeotropism to produce an approximate balance, the final result being determined by the stimulus of light ; but when the balance is disturbed by placing the plant on the clinostat, the light-stimulus is not strong enough to produce a condition of equilibrium. This view is the same as that given in The Tower of Movement in Plants , and is in accordance with the principle there laid down, — that the chief movements in plants are due to modifications of the circumnutatory motion. II. When a cutting — for instance, a piece of a willow-branch — is placed in circumstances favourable for growth, it produces roots at its lower end, while the buds at its upper end grow out into branches. The experiments of Vochting * on the growth of cuttings were made by suspending pieces of stems and branches, &c. in large, darkened jars, the air in which was kept constantly moist by a lining of wet filter-paper. The cuttings were suspended both in the normal position, that is, with the upper end upwards, and also upside down. Vochting found, as a general result, that there is a strong tendency for the roots to appear at the basal end, t and the branches to be developed at the apical end, whether the cutting had been hung apex up- wards or downwards in the glass jar. Vochting believes that the growth of roots at the base, and of branches at the apex of a cutting, is determined chiefly by an innate inherited growth-tendency. When the knife divides a branch into two cuttings, it separates a mass of identically constituted cells into two sets ; one forming part of the apex of the lower cutting, and another set which forms part of the base of the upper cutting. And under appropriate circumstances one of these sets of cells might develope into roots, the other into adventitious buds. It is Vochting’s belief that the morphological positions of these sets of cells, the fact of one being at the base, and the other at the apex of a cutting, chiefly determines the course of their subsequent develop- ment. The idea may be expressed somewhat familiarly, by saying that each cutting into which a branch is divided is able to distinguish its base from its apex, and can tell where to produce the growth of roots and buds, by means of an internal impulse which is independent J of the external forces, gravitation and light. * Organbilduny im Pjlanzenreich. Bonn, 1878. t The basal is that end of a cutting nearest to the parent plant ; the apical end is the opposite end. \ Vochting states distinctly that gravitation and light do affect the positions in which organs are developed in cuttings, but he considers the internal impulse to be a stronger determining cause. SCIENTIFIC SUMMARY. 75 The theory which Sachs has brought forward in his paper on Staff und Form der Pflanzenorgane * is entirely opposed to that of Vochting. Sachs conceives that Vochting’s ‘morphological force’ is not a hereditary tendency, but a tendency produced by the action of external forces during the growth of the formative cells. Thus Sachs believes the force of gravity acting on the developing cells of an organ produces on it a pre- disposition or enduring impulse, which manifests itself in the results which Vochting ascribes to a hereditary force. The mode in which Sachs believes gravitation to act is interesting, not only in itself, but also as a modification of a theory of Du Hamel’s. It is assumed that difference of material is a necessary concomitant of difference of form, and that accordingly the materials from which roots are formed are chemically (used in a qualified sense) different from those which supply the branches. Sachs’ theory supposes that the growth of roots or buds at a given place will be determined by the distribution of the root- and branch-forming materials, and that the distribution of these materials is regulated by the force of gravity. The root material is in a certain sense geotropic, and flows downwards, the branch material having the opposite tendency. But they are not supposed to be simply geotropic ; the tendency of the root-material to flow to the base of a branch is carried on after the branch has been made into a cutting, and hung upside down, so that the root material flows upwards towards the base of the cutting, because that end was originally downwards, and vice versa with regard to the branch-forming matter. The observations on the bramble, which form the subject of the present paper were carried out with the object of deciding, for a particular case, whether the growth was determined by a morphological force, or by the after-effect of gravitation. The long sterile shoots of the bramble are well known to possess the power of rooting at their ends. The terminal bud is thus protected during the winter, and the store- of nutriment contained in the club-like thickened end of the branch forms a starting-point for new growth in the spring. It is commonly the long pendent branches growing vertically downwards that reach the ground and form roots. It might, therefore, be supposed that gravitation determines their growth at the lower end of the branch, just as, in a cutting made from an erect willow-branch, the roots grow at what was originally the lower end. But observations made on brambles under certain circumstances show that this is not the case. When brambles grow on a steep bank, the majority of the branches grow down-hill at once, or else straggle more or less horizontally along the bank, and finally turn down- wards. But a certain number of branches grow uphill, and some of these take root at the apex. When, therefore, we find on the same individual plant some branches forming roots at the physically lower, and others at the upper end, we may feel sure that the distribution o root-growth in the bramble is not determined by gravitation or its after effect. We must believe that there is a morphologically directed impulse which tends to the production of roots at the apex of the branch, whether the direction of its growth has been upwards or downwards. It is true that in the observed * Arbeiten des Bot. Inst. Wurzburg, 1830, p. 452. 76 POPULAR SCIENCE REVIEW. cases the extreme end of the branches was bent, so that from 1 to 9 inches was inclined at from 2° or 3° to 5° below the horizon ; but it can hardly be imagined that this fact influences the growth of roots at the apex, and experiment shows that it is not necessary that even a single inch should be inclined below the horizon. A bramble branch was tied apex upwards to a vertical stick, and was surrounded by damp moss, and covered with water- proof cloth ; imder these circumstances a plentiful crop of roots sprang from the terminal part of the branch. This result, combined with observations made with brambles growing on a steep bank, shows conclusively that an internal impulse or morphological force regulates the growth of roots in the bramble. When a cutting is made from a bramble, the only growth that takes place is the development of the axillary buds at the apical end of the cutting. Under certain circumstances these side shoots take on a root-bearing function. They are stunted in growth, being perhaps 10- 12 mm. in length, and 3 or 4 mm. or more in breadth ; they assume a peculiar club-like form, being thicker at the apex than at the base, and are clothed with rudimentary scale-like leaves, from among which a number of relatively large roots spring forth. In order to determine whether the production of this root-bearing type of shoot is determined by gravitation, or by a ‘ morphological force,’ cuttings were made from branches whose direction of growth was above the horizon. Such cuttings were hung apex upwards, and it was found that the most apical buds were capable of developing, under these circumstances, into the root-bearing type of branch. Similar rooting side-shoots are produced by cuttings made from branches which have grown beneath the horizon, and it is therefore clear that gravitation is not the determining force in this form of root production. When the end of a branch is injured, as often occurs when a bramble grows along the ground near a pathway, the most apical bud or buds produce branches which take root, instead of the parent branch ; either an ordinary branch is produced, which after a certain course of time makes roots at its extremity ; or under certain circumstances the stunted, club-shaped, root-bearing side shoots may be developed, whose whole formation is devoted to the bearing of roots. It is therefore clear that the production of such shoots in cuttings is the same process that occurs in branches injured in a state of nature — a process which enables the branch to perform the function whose normal performance has been interfered with. And this fact enables us to see in what way a morphological growth-impulse is better fitted for the requirements of the case than any possible dependence on gravitation as a guiding force. When the end of the branch is injured, it is clear that if a branch is to be developed to carry on the function of the injured apex, it will have the best chance of success if it starts from the position already gained by the end of the original branch before it was injured. Therefore the bud which is nearest to the injured apex will be the most suitable one to be developed into a new branch. And this is equivalent to saying that the place where the new development is to take place is determined morphologically, and not by gravitation. Thus in the bramble the behaviour of cuttings is a repetition * of the See Vochting, Organbildung , p. 107. SCIENTIFIC SUMMARY. 77 normal process of restoration of a deranged function in the plant ; how far this is the case with other plants must remain at present undetermined. Influence of Light upon Germination. — M. A. Pauchon has made a series of experiments to determine whether light has or has not any influence upon the germination of seeds. From various disturbing causes, his first experi- ments by the direct method gave no satisfactory results; he therefore adopted another plan, and compared the respiratory activity of seeds sub- mitted to different conditions of light and obscurity, measuring by their absorption of oxygen. Taking identical parcels of seeds, of equal number and equal weight, he arrived at the following conclusions : 1 . Light constantly accelerates the absorption of oxygen by germinating seeds. The advantage in favour of light varies from one quarter to one-third of the amount of oxygen absorbed by the seeds kept in the dark. 2. There is a relation between the degree of illumination and the amount of oxygen absorbed. The influence of light is very manifest under a clear sky and bright sun ; with a cloudy sky it gradually decreases. 3. The acceleration produced by exposure to light persists for some hours after the exposed seeds are in the dark. 4. The difference in the quantities of oxygen absorbed in light and dark- ness are greater in winter than in summer ; hence it would appear that the influence of light upon this respiration is more intense at low temperatures. In a second communication, M. Pauchon gives the results of a series of experiments in which he determined the amounts of oxygen absorbed, and of carbonic acid exhaled, by identical parcels of germinating seeds in the light and in obscurity, thus ascertaining the different values given by these CO2 conditions to the fraction -|gp . His experiments were made upon two seeds of opposite types — the oleaginous and albuminous seeds of Ricinus — and the starchy and non-albuminous seeds of the Haricot. His conclusions are as follows : 1 . The quantity of oxygen absorbed was, as before, always greater under the action of light. With the Ricinus the amount of carbonic acid exhaled was a little greater in obscurity than in the light; but with the seeds of Phaseolus multi/lorus the result was different. CO2 2. In obscurity the relation was, with the Haricot at least § above that ascertained for the Ricinus. With the latter it attains O’ 58 in an experiment suspended on the fourth day, and 077 in one lasting five days. With the Haricot the relation is 1T4 in four days, and 1*03 after the sixth CO2 day. The prolongation of the experiments tends to render the relation -q- equal to unity, whatever may have been its original value. CO2 3. Comparing the relation -q- in a single experiment, there is always in favour of darkness an advantage of about J in the value of this relation, i. e. for the same amount of oxygen absorbed, seeds placed in darkness exhale more carbonic acid than those in light — sometimes, indeed, the absolute quantity exhaled in light is less than that set free in darkness. In the light there is always less carbonic acid exhaled than oxygen absorbed, and the reverse is the case in the dark. 78 POPULAR SCIENCE REVIEW. 4. These facts explain the conversion of legumine into asparagine. Asparagine in leguminous plants only disappears in plants exposed to the iglit. Pfeifer’s researches have shown that asparagine is poorer in carbon and hydrogen, and richer in oxygen than legumine and other proteic materials. The transformation of legumine into asparagine only takes place in the light, because this accelerates the absorption of oxygen, but his condition would not suffice if the carbonic acid exhaled were not less in quantity than the oxygen absorbed. A part of the oxygen, not represented n the exhaled carbonic acid, is probably fixed by the albuminoid principles during the formation of asparagine. — Comptes Rendus, 2 Qth October avid 22nd November , 1880. CHEMISTRY. The Liquefaction of Ozone and its Colour in the Gaseous State. — Ozone, such as one usually prepares, possesses so little tension in oxygen, at most 53 mm., that the physical properties of this body are hardly known and dis- tinguished from those of oxygen. One knows the difficulties which Soret has so ably overcome in determining the density of ozone by operating on weakly ozonized oxygen. One of the fixed physical properties of this body is its heat of formation, which was accurately determined by Berthelot, in spite of the state of dilution in which it is found on leaving the apparatus for ozoni- zation. The preparation of a mixture, very rich in ozone, is then the first condi- tion to be fulfilled in order to acquire new notions of this curious body. Hautefeuille and Chappuis have already established the fact that the isomeric transformation of oxygen submitted to electricity, obeys simple laws, and that the proportion of ozone increases but very little with the pressure for every temperature ; whereas, in passing from 20° to — 55°, the proportion of ozone increases five-fold. Removed from the action of electrical discharges, the mixture of oxygen and ozone ceases to be a homogeneous and balanced system ; in spite of that, the mixture is preserved without appreciable altera- tion so long as a constant temperature is maintained, if we operate on it below 0°. This relative stability of ozone allows us to compress the mixture and to obtain the tensions of ozone of several atmospheres. As it is necessary to prepare ozone, destined for these experiments, under the strongest possible tension, one mu3t ozonize oxygen at a very low tempera- ture. Consequently the oxygen remains a quarter of an hour in an apparatus of alternating discharges, whose concentric tubes of thin glass are dipped into chloride of methyl; then one passes it into a test-tube, terminated by a capillary tube of the Cailletet apparatus. This reservoir, of about 60cc, at first empty and kept at — 23°, not being able to fill itself at one time under a pressure approaching 760 mm., is put rapidly in communication, five times successively, with the electric apparatus, the capacity of which cannot ex- ceed 20cc. In a quarter of an hour, one succeeds by this method in filling the test-tube with a mixture of oxygen and ozone, very fully charged with the latter gas. The test-tube is then taken away from the chloride of methyl and separated from the electric apparatus, and the gas which it contains is SCIENTIFIC SUMMARY. 79 driven slowly back by mercury, cooled to 0° in a capillary tube maintained at — 23°. Tbe mercury, which transmits the pressure of the hydraulic press, does not impoverish the gaseous mixture as quickly as one might fear. A solid glaze is formed on the surface of the metal which rapidly limits the action ; the heating of the gas during the compression is more formidable. In spite of these difficulties one succeeds in increasing the tension of the ozone to a considerable degree. From the first working of the piston, the capillary tube becomes of an azure blue ; this coloration is intensified in' proportion as one reduces the volume of gas ; and if the tension of the ozone is brought by the compression to be one of several atmospheres, the gas is indigo blue, and the meniscus of mercury, seen through the gas, is then of a steely blue. The blue colour of the gas becomes less intense, and the mercury regains its usual metallic appearance, as soon as one diminishes the tension of the ozone. The preceding mixture contains enough ozone for one to observe a thick, white mist at the moment of the expansion which succeeds a compression of 75 atmospheres. It is not then necessary to compress the ozonized oxygen as much as pure oxygen (300 atmospheres) in order to determine by a sudden expansion the momentary formation of a mist, a certain sign of liquefaction or even of solidification. A comparative study of the mixtures of oxygen and ozone, and those of oxygen and carbonic acid, shows that in very comparable conditions the ex- pansion ought to be sensibly stronger with the ozone than with the carbonic acid, for one to begin to perceive a mist. Ozone would then be a little easier to liquefy than carbonic acid. The mixture of oxygen and ozone contains an explosive gas, and should always be compressed slowly and cooled ; for if one does not not meet these conditions, the ozone decomposes with an escape of heat and light, and there is a loud report accompanied by a flash of yellowish light. Berthelot has found that the transformation of oxygen into ozone absorbs 14 cal., equivalent to 8 (O3 = 24 gr.) ; ozone may therefore be placed beside ex- plosive gases ; the experiments show that, like them, this body is susceptible of sudden decomposition. One may also observe a portion of these new facts by compressing oxygen which has gone slowly through the electric apparatus at ordinary temperature ; for if we compress this gas rapidly in a capillary tube, placed in some water at 25°, we often destroy the ozone with explosion ; but if this same gas is cooled at — 23°, the ozone which it contains may be brought to a tension of 10 atmospheres, and may be preserved for hours in these con- ditions of temperature and pressure, if the gas is separated from the mercury by a column of sulphuric acid. It is ascertained, then, almost equally clearly as in the preceding experi- ment, that ozone is a gas of a beautiful azure blue, for its colour is so intense when one increases its density tenfold, that it could be seen in a tube of 0m,001 internal diameter, when operating in a very poorly lighted room in the laboratory of l’Ecole Normale. It is therefore established that ozone under a strong tension is a coloured gas : but may the same be said of ozone at the tension of some millimetres ? The blue colour characterizes ozone as surely as its smell; for at all the tensions we find it on examining the gas to a sufficient depth. It suffices in 80 POPULAR SCIENCE REVIEW. order to make this manifest, to interpose between the eye and a white sur- face a tube of 1 m. in length, traversed by the current which has passed through the electric apparatus of Berthelot. The colour which the gas then possesses reminds one of the blue colour of the sky ; this blue is more or less deep in proportion to the time the oxygen has remained in the apparatus, and is consequently more or less rich in ozone. As soon as one stops the electric tube, the coloration disappears, the ozonized oxygen being replaced by pure oxygen. Ice at High Temperature. — A short communication on this subject to the Chemical News by T. Carnelley (vol. xlii. 130) draws attention to the follow- ing points. Numerous experiments which have been made during the last weeks on the boiling-point of bodies under reduced pressure have led to the following conclusions respecting the conditions which are necessary for a body to exist in the fluid condition. They are as follows : (1) In order to convert a gas into a liquid, the temperature must be below a certain point — a point which Andrews termed the critical temperature of the substance ; otherwise no pressure, however great, is able to convert the gas into a liquid ; and (2) in order to convert a solid body into a liquid, the pressure must be above a certain definite point, which the author proposes to call the critical pressure of the substance : otherwise no temperature, however high, is able to convert the substance into a liquid. If the second condition deduced from the above is correct, it follows that, when the required temperature is reached, the conversion of the body into a liquid only depends on the pressure applied to it; so that if we keep the pressure on a substance below this critical pressure, no amount of heat will convert it into a liquid. In this case the solid substance passes directly into a gaseous condition ; in other words, it sublimes without melting. When this conclusion is arrived at, it is easily seen that, if this representation is a correct one, it is possible to keep ice in the form of ice at temperatures which lie far above the melting point. After a great number of experiments which proved to be failures, Carnelley had the good fortune to attain the desired result, and, to keep ice at so high a temperature that it was impossible to touch the tube which held it without burning one- self. This result has been obtained many times, and with great ease ; and not only this, but in one case a small quantity of water was frozen in a glass vessel, which was so hot that it could not be touched by the hand without burning it. I have kept, he writes, a quantity of ice a considerable time at temperatures which lie far above the ordinary boiling point, and then it slowly sublimed away without first melting. These results are arrived at when the pressure is kept down below 4 6 mm. of mercury, that is to say, below the tension of aqueous vapour at the freezing point of water. Other substances show the same properties. The most remarkable is mercury chloride, because in this case the pressure need only be reduced to 420 cc. If the pressure be allowed to rise higher, the chloride immediately becomes liquid. In the case of water, there are certain details of manipulation which require attention, and which will be communicated in a second paper. Guthrie's Cryohydrates. — When investigating the freezing-point of dif- ferent salt solutions, Guthrie discovered some peculiar solid products to which he gave the name of cryohydrates. They are definite hydrates of the salts in question, which have a fixed solidifying and melting point, and in SCIENTIFIC SUMMARY. 81 which he considers the salt to he in chemical combination with the ice. In 1877 Pfaundler showed, from theoretical considerations, that the properties which Guthrie found the cr yohydrates to possess occur in the same way in the case of a mixture of ice and salt, and as such he regards the cryohydrates. Of the same view is H. Offer in a paper which contains the following conclusions against the existence of cryohydrates as chemical compounds. Against the possibility of a chemical combination existing in these bodies is the relative quantity of water found in them. The cryohydrates of NH4C1 contain 12'4 of water ; that of KC1, 16‘61 ; that of Na2 C03, 92’75 ; that of K2 S04, 114’ 2 of water, and so on. He finds throughout numbers which give expression to no stochiometric law, and with much greater probability indicate mechanical mixtures. Furthermore, there is the circumstance that no cryohydrate, when becoming solid, furnishes a distinct definite crystal, which, as is well known, is quite characteristic of a chemical compound, but yields in each case an opaque, entangled, crystallized mass. If cryohydrates are placed in alcohol, it is foimd that the ice is dissolved out of the substance, beginning of course with the outer layer ; and the salt remains asadownlike shell of the inner unchanged cryohydrate : only after longer action did the entire mass fall to pieces. If, on the other hand, a cryohydrate is placed in water, the outer layer is, first of all, changed into transparent ice ; this coating of ice increases at the cost of the cryohydrate kernel, step by step inwards, until at last the kernel vanishes, and a piece of ice the same size as the cryohydrate remains. Here the water has evidently gradually taken up the salt from out of the mixture. In the case of four different cryohydrates calorimetric determinations of the heat of solution were made, and the cooling observed in each case compared with those which, under similar conditions of temperature, salt and ice of the cryohydrate alone would furnish. In all experiments, the difference between the heat absorbed by the cryohydrates and by the constituents separately is so small, that they were within the errors of experiment, and may be estimated as nothing. Herr Offer determined the specific gravity of a number of cryohydrates, and compared them with that of their constituents, and in a whole series of cases found a pretty good accordance. These results, while not fully proving the cryohydrates to be mere mix- tures, yield results which, taken with the others above referred to, give to the assumption a great degree of probability. ( Sitzungsher . Wien. Akad. der Wiss. 1880. lxxxi. 1058.) Fire Extinction. — Some comparatives experiments have been made on a plot of ground adjoining the Savoy, Strand, with water and sodium silicate, as recommended by Herr Windsperger. Two piles of timber, 9 ft. long, 7 ft. high, and 4 feet deep, were filled in with straw, well saturated with petroleum and benzol in equal quantities, and ignited. After burning for five minutes, operations were commenced by throwing water on one, and sodium silicate on the other, with a handpump. In the course of about one ; minute the fire treated with the silicate was extinguished, while that treated with water did not give in till about four minutes. And it was further found that twelve gallons of the solution and twenty-two gallons of water had | been used. The results of the experiment were most conclusive. The Conditions attending Explosion. — It appears that when the rocket NEW SERIES, YOL. Y. NO. XVII. G * 82 POPULAR SCIENCE REVIEW. exploded during the second week of December at the Royal Arsenal, Wool- wich, it was already fully charged, and the maximum pressure had been applied in safety. It is the custom, it seems, however, to leave the pressure on the rocket for one minute after reaching the maximum, and it had been so left for three quarters of a minute when the explosion occurred. The usual conjecture that such accidents are produced by an atom of dirt, the friction of the tamping tools, or any such causes, are therefore untenable in this case, and the origin of such explosions remains unknown. In future the rockets are to be filled and pressed in a bomb-proof room, and the men em- ployed on the work are to be protected by iron shutters from any mishap. GEOLOGY AND PALAEONTOLOGY. Spirifer Icevis, fyc. — Prof. H. S. Williams communicates to Silliman's Journal an abstract of some researches made by him upon the Spirifer Icevis of the Portage group of New York, and its relations to other forms occurring in other groups of Palaeozoic rocks. His remarks are interesting as illustrating in a very remarkable manner the affiliation of so-called species in successive formations, detailed examples of which have rarely been so clearly put forward. The more important characters of the species are distributed by Prof. Williams under the following seven heads : — (1) Form and proportions of the shell; (2) size; (3) prominence and over-arching of the beak; (4) the short and high cardinal area ; (5) the triangular aperture covered by an arched pseudo-deltidium ; (6) the smoothness (non-plication) of the surface ; (7) the concentric series of minute radiating lines covering the surface. The last peculiarity has not previously been recorded as characteristic of the species, nor has it been noticed by writers on Devonian Brachiopods. By careful comparison of characters, Prof. Williams arrived at the result that a genetic relationship exists between Spirifer Icevis and S. fmbriatus, which occurs in the Hamilton and earlier formations. Then, tracing back the forms exhibiting the peculiar combination of characters which appeared to be essential to the two species just mentioned, he found the earliest trace of them in the Niagara formation at the bottom of the Upper Silurian. Here the central type of the primitive species is S. crispus, His., of which S. bicostatus, Hall, is probably an extreme variety, and S. sulcatus, His. an extreme variety in the other direction. Spirifer crispus, with corresponding varieties, is very abundant and very widely distributed, occurring at the horizon indicated wherever that is represented. The author also traced this type of Brachiopods forward to Spirifer glaber, Mart., and other Carboni- ferous forms. The following is an abridgment of Prof. Williams’ conclusions : — What- ever theoretical description we may give to species, we have here, in the first place, an abundance of organisms whose remains are found in Upper Silurian rocks of Europe and America, presenting a few clearly marked, distinctive characters variously developed in the individual forms, but so grading in the different varieties as to cause careful naturalists to associate them as varieties SCIENTIFIC SUMMARY. 83 of a single species. There are well-marked typical characters, with great variability of the characters themselves. In the upper part of the Upper Silurian, we find the same typical characters, with a greater predominance of one or other of the variations; hut yet, in the Corniferous and Hamilton, the main type is represented with some variations strongly marked and apparently fixed, but still recognized as varieties simply. In the Portage we see, under peculiar conditions, a solitary race with greatly exaggerated size ; a luxuriant form, but still presenting the typical characters of the second varietal type. The same luxuriance of growth characterizes the Carboni- ferous forms ; but the earliest form, S. crispus of the Niagara, possessed all the characters which afterwards appeared in the later representatives. Thus the whole may constitute a physiological species ; but by intercrossing and by local conditions modifying the offspring, well-defined groups are produced, which would be called races if we knew their history, but which are called species because they appear at such widely separated geological periods. These separate groups, however, develope no neiv characters ; and there is every evidence for the belief that the species has lived through this long geological time without losing its character, and that all that has resulted from great time and change of conditions has been the fixing into race-groups of the original variable characters of the species. The species, at its first appearance in the Silurian, presented a decidedly new combination of cha- racters for the genus, and also much variation. When once these specific, though variable, forms appeared, they lived till the variations which could be played on them were exhausted ; and the species ceased to live and be- came extinct, either near the close of the Carboniferous, or not till later in the Mesozoic. Prof. Williams gives the following table of the distribu- tion of the forms above referred to in the American Silurian, and Devonian rocks Chemung Portage Hamilton Corniferous Oriskany prsematurus . . . laevis Lower Helderberg Niagara . tribulis . Saffordi (pars) fimbriatus . fimbriatus . subumbona octocostatus . modestus cyclopterus (pars) . . . Vanuxemi sulcatus (pars) . crispus crispus . bicostatus N.Y.&Tenn. Maryland New York ^ New York ^ Shale ) Limestone — ( Amer . Journ. of Science, December, 1880.) Grits and Sandstones. — Mr. John Arthur Geological Society, on the 15th December, a paper on the structural characters of grits and sandstones. He described the microscopic and chemical structure of a large series of grits, sandstones, and, in some cases, quartzites, of various geological ages, noticing finally several sands of more or less recent date. The cementing material in the harder varieties is commonly, to a large extent, siliceous. The grains vary con- siderably in form and in the nature of their enclosures, cavities of various kinds and minute crystals of schorl or rutile not being rare. Mr. Phillips Phillips brought before the very interesting and valuable 84 POPULAR SCIENCE REVIEW. drew attention to tlie evidence of tlie deposition of secondary quartz upon the original grains, so as to continue their crystal structure, which sometimes exhibits externally a crystal form. This is frequently observable in sand- stones of Carboniferous, Permian, and Triassic age. Felspar grains are not unfrequently present, with scales of mica and minute chlorite and epidote. The author then considered the effect of flowing water upon transported particles of sand or gravel. It results from his investigations that frag- ments of quartz or schorl less than ■£/' in diameter retain their angularity for a very long period indeed, remaining, under ordinary circumstances, un- rounded ; but they are much more rapidly rounded by the action of wind. It is thus probable that rounded grains of this kind in some of the older rocks, as, for example, certain of the Triassic sandstones, may be the result of AEolian action. Abnormal Geological Deposits in the Bristol District. — On the 17th November, Mr. Charles Moore read a paper on certain curious deposits in the country about Bristol, which may be regarded as a continuation of researches published by him some thirteen years ago upon similar pheno^ mena in the districts of Somersetshire and South Wales. The author remarked that the Frome district shows numerous un- conformable secondary deposits and 1 vein-fissures ’ resting upon or passing down through the Carboniferous Limestone, as described in his former paper {Quart. Journ. Geol. Soc. vol. xxii. p. 449). He gave some further particulars as to these deposits, and especially described the occurrence of Post-pliocene, Liassic, and Bhaetic deposits in the Microlestes-quaxTy near Shepton Mallet. Here the lower part of a fissure is filled with a brown marl, containing crystals of carbonate of lime, and numerous remains of Arvicolee, Frogs, Birds, and Fishes. The jaws of Arvicolee were very abundant. He then proceeded to describe the occurrence of similar phenomena in the Bristol area, as at Durdham and Clifton Downs, in the gorge of the Avon at Clifton, at Ashton and Westbury-on-Trym, in the Yate rock, in Nettle- bury quarry, at Clevedon, and on the Thornbury railway. He noticed the occurrence in the infillings of fissures traversing the Carboniferous Lime- stone of these localities of fossil remains belonging to various geological ages ; and he especially called attention to the presence in different deposits of an immense number of small tubular bodies of doubtful origin, for which, should they prove to be of organic nature, he proposed the name oiTubutella ambigua. By different authorities these little bodies have been assimilated to Serpulae (Filograna), insect-tubes, and the casts of the fine roots of plants. With regard to the age of the fissure-deposits, the author remarked that although in some fissures the infilling shows a mixture of organisms, in most cases each 1 vein ’ appears to have an individuality of its own, and thus the veins represent intervals of geological time clearly distinct from one another, different fissures showing infillings of Alluvium, Oolite, Lias, Rhsetic, and Keuper beds. The presence of his Tubutella he considered to indicate fresh-water conditions. The author also referred to the discovery of Thecodontosaurus and Falceosaurus many years ago at the edge of Durdham Down, and discussed the age of the deposit containing them, which wras originally supposed to be I ! SCIENTIFIC SUMMARY. 85 Permian, and was referred by Mr. Etheridge to the Dolomitic Conglomerate at the base of the Keuper. The author stated that he had found remains of the same genera in Rhaetic deposits at Holwell and Clifton Down, and had hence been led to refer the two genera to that age. He stated, however, that he had since discovered teeth of Thecodontosaurus identical with those of the Bristol area in a deposit belonging to the middle of the Upper Keuper at Ruishton near Taunton, and recognized certain differences between these teeth and those of the same genus from the Rhaetic beds of Holwell ; hence he was led to give up the notion that the former were of Rhaetic age, and to refer them to the Upper Keuper ; but he remarked upon the interesting fact that, while most of the generic forms of the Keuper are represented in the Rhaetic, the species differ. A Cretaceous Snake. — Hitherto the first indications of the existence of Ophidian reptiles have been obtained from the earlier Tertiary deposits, especially the London Clay of Sheppey, from which Prof. Owen described two genera of these animals under the names of Pcdceophis and Paleryx. M. H. E. Sauvage has communicated to the French Academy ( Comptes Rendus, 18th October, 1880) the discovery in the Charente of vertebrae of a snake in sandy deposits of the Cenomanian epoch ; that is to say, of the age of our Upper Greensand. The vertebrae are about 14 millim. in length and are considered to indicate a serpent about 3 metres (10 feet) long. M. Sauvage briefly describes the characters of these vertebrae, in which he finds resemblances to Boas, Rattlesnakes, and Typhlopidae, and especially to the the latter, which may be regarded as indicating the passage from the Serpents to the Lizards. He gives the new Cretaceous Ophidian the name of Simoliophis Rochebruni, in honour of its discoverer, M. Tremaux de Rochebrune. MINERALOGY. Spodumene and the Results of its Alteration. — This is the title of a fourth paper by G. J. Brush and E. S. Dana ( Amer . Journ. Sci., 1880, October , xx. 257), on the mineral locality at Branchville, Connecticut. Spodumene of this locality occurs in large masses, showing distinct cleavage, but seldom any ap- proach to crystalline form. The blocks often weigh several hundred pounds. It is also found in an altered condition as nuclei of distinct pseudomorphous crystals, and one mass measured three feet in length, with a width of eight inches and a thickness of two inches. An analysis of a specimen gave the numbers : — Silicic acid . . 64-25 Alumina . 27-20 Iron peroxide 0-20 Lithia . 7-62 Soda 0-39 Potash . . Trace. Ignition * 0-24 99-90 86 POPULAR SCIENCE REVIEW. The litliia is in larger quantity than in specimens of spodumene from any other locality. As a result of the alteration of the spodumene, two substances were found, one, which the authors term j3 spodumene, which is made up of albite and a new lithium mineral, to which they have given the name of eucryptite ; and the other is cymatolite, an aggregate of albite and muscovite. Eucryptite dissolves with gelatinization in hydrochloric acid and has the composition Li2 Al2 Si2 08, and the albite Na2 Al2 Si6 016. The cymatolite received its name, in 1867, from Shepard, having been found at Goshen and Norwich, Mass. The specimens found by the authors of this paper have the composition : — Silicic-acid . . 60*55 Alumina . 26*38 Manganese oxide . 0*07 Soda 8*12 Potash 3*34 Lithia . 0*17 Water 1*65 100*28 This has the composition of one molecule muscovite and one molecule of albite, which is curious. With these minerals occurs microcline, having the composition : — Silicic acid . . 64*55 Alumina , ■ . 19*70 Potash , . 15*62 Soda , 0*56 Ignition • 0*12 100*57 This is largely used for making porcelain ; it is obtained in cleavage masses, as large as can be handled and nearly pure, a single continuous cleavage- surface ten feet long has been observed. After describing the killinite found associated with these minerals, we have some interesting speculations on the relations in method of occurrence between the various minerals produced by the alteration of the spodumene ; and the genetic relation between the original spodumene and the various products of its alteration, concerning which we must refer the reader to the paper itself. Peckhamite. — This name has been given by Dr. Lawrence Smith, of Louisville, Kentucky, to a new meteoric mineral occurring in the Emmet County meteorite. When broken, this mineral has a greasy aspect, and a more or less perfect cleavage, and its yellow colour has a greenish hue. In structure it differs widely from olivine, as may be seen under the microscope. Small rounded nodules, several millimetres in diameter, are found in the in- terior of the mass, sometimes of irregular form, from which fragments nearly pure can be detached. Its specific gravity is 3*23, and chemical composition was found to be Oxygen. Silicic acid . . 49*50 49*59 25*73 Iron protoxide . 15*88 17*01 3*77 Magnesia . . 33*01 32*51 12*76 98*29 99*11 SCIENTIFIC SUMMARY. 87 The ratios above give very closely the formula, 2 Si R + Si R2, being that of two atoms of enstatite or bronzite plus one atom of olivine. The mineral is named after Prof. Peckham, to whom the author is indebted for every facility in prosecuting his researches in connexion with this remarkable meteorite. Examination of the Red Felspar of the Granite from Lyme, Conn. — A fragment of the beautiful coarse granite from the McCurdy quarry at Lyme, Conn., was given by Prof. Blake to M. Des Cloizeaux for optical study. He finds it to be a true microcline, but of an altogether peculiar structure, for the study of which the ordinary magnifying power is not sufficient, the con- stituent parts being exceedingly minute. The face of every cleavage shows a series of very small spots of albite, interspersed with hemitropic plates of microcline, the angle of extinction of which — not easily determined with great exactness — is 13° to 15°, measured from the edge between the two cleavage-faces. Across the second cleavage, the structure is, as it were, fibrous, and, with a high power, the angle of extinction is found to be from 7° to 9° for the microcline, and from 18° to 20° for the albite. ( I have never before/ he writes, 1 met with a felspar with the elements so crowded together and so fine.’ He hopes the proprietor may be able to supply some fragments of this beautiful granite. An examination of such specimens would be of great interest on account of the enormous size of its felspar individuals.- - ( Amer . Journ. Sci., 1880, October, xx. 335.) PHYSICS. Effects of Magnetism on Iron and Steel. — According to some recent investigations by Prof. Righi on the effects of magnetism on iron and steel, (1) magnetism produces in iron and steel an increase of dimensions in direction of the magnetization. (2) On cessation of the magnetizing force a part of this increase remains, and more or less of it according to the coercive force. (3) The elongations are proportional to the square of the current’s intensity when this is not very great. (4) When, after a strong current through the spiral, a weak current is sent in the opposite direction, it produces a shortening ; but even when it is strong enough to demagnetize the bar, the latter retains a greater length than in the normal state. (5) During reversal of the polarity of a bar its length becomes momentarily less, and it oscillates in length. (6) A bar of wire or iron traversed by a current contracts at the moment of closing the circuit. (7) On opening the circuit it elongates, but this elongation is less than the initial contraction, indicating that transverse magnetism partly remains. (8) In reversal of the transverse polarity the bar elongates for a moment, and thus oscillates in length. (9) The contrac- tion produced by a current is greater when the bar has before been longitudi- nally magnetized. (10) Some iron bars show a tendency to spiral magnetiza- tion, i. e., to rotate the magnetic axes of their molecules in the direction of the spiral. This, says Nature , is shown by the contractions caused by a current passing through the bars, which are different according 88 POPULAR SCIENCE REVIEW. to the direction of the current and that of the previous longitudinal magnetization. The Photophone has "been reproduced in an exceedingly simple form by Mr.* Shelf ord Bidwell. The transmitter is a disc of thin microscopic glass silvered on its anterior surface, and placed in front of a tube by which the voice is conveyed to it so as to excite vibration. The lime, or electric light, is reflected from this mirror through a convex lens, so as to render the rays parallel ; these being received on a second lens at some distance, and again concentrated on a selenium receiver. This is the most important part of the apparatus. It consists of a slip of mica, 2j inches long and f inch broad, round which is wound No. 40 copper wire in the form of a flat screw, with a pitch of XV of an inch. The ends are fixed through holes drilled in the mica. A second wire is then wound beside, but not touching, the first. A few grains of vitreous selenium are melted and dropped on the surface of the mica, being afterwards evenly spread by means of another slip of mica. The temperature should be just above the fusing-point of selenium. It is then allowed to cool. It is next annealed for several hours and allowed to cool very slowly. The terminals of this cell are joined up with a battery of eleven Leclanche ele- ments and a pair of Bell telephones wound with finer wire than usual, in larger quantity than that required for ordinary telephonic communication. The voice is very fairly conveyed across a space of ten feet and into a neigh- bouring room by this simple form of apparatus. The Thermic and Optical behaviour of Gases, under the influence of the electric discharge, has been further investigated by Wiedemann, and the results have been given at some length in the Annalen. He had before shown that when a mixture of two gases, of which one is a metallic vapour and the other nitrogen or hydrogen, is exposed to the electric discharge, the lines of the metallic vapour are seen in the spectrum, while those of the other gas remain invisible ; so that the propagation of electricity is entirely due to the metallic vapour, — the discharge being entirely discontinuous. He had also shown that the temperature of the gas illuminating a Geissler’s tube may be below 100°. It is thus proved that the usual theory referring the emission of light by gases to an increase of temperature up to the point of incandescence is no longer tenable, and requires fresh experimental examina- tion. In this communication, he has thoroughly examined the thermic relations of the discharge of the induction machine under different conditions, and has discovered a peculiar behaviour of positive and negative electricity. Experiments follow to determine numerically the conditions under which the transformation of the band-spectrum into the line-spectrum occurs in hydrogen. The apparatus employed is described at length. It appears among other results that as pressure diminishes, the quantities of heat evolved diminish to a minimum and then rise again. With hydrogen the heating is generally less than with air. The number of discharges increases as the pressure diminishes, and then decreases again. The heating at the positive electrode diminishes continually and rapidly as the pressure decreases; that at the negative electrode at first decreases, and then increases rapidly. Electric Conductivity of Carbon. — Dr. Werner Siemens has lately de- scribed to the Berlin Academy a new series of experiments on the electric SCIENTIFIC SUMMARY. 89 conductivity of carbon, and the way it is affected by temperature. He finds that of gas retort carbon at 0 deg. = 00136 if mercury = 1 — and the co- efficient of increase of conductivity 0'000345 per degree Celsius. The arti- ficial carbon rods produced by compression of carbon powder also show greater conducting power with increasing temperature, but the increase is not so great as in retort carbon. The electric conductivity of gas-carbon and its variability under pressure has been re-examined by MM. Naccari and Pagliani, and in such a way as to throw some doubt and some light on the theories advanced respecting the common microphone. Carbon prisms were in- serted in a Wheatstone’s bridge to determine their resistance. When subjected to great pressures the resistances of the rods of carbon showed scarcely any change. Hence it appears that the changes of conductivity which carbon exhibits in the microphone and in the carbon telephone under varying pres- sures, are due to mere changes in the external contact. The similarity of Sulphur to Selenium in respect of its variable con- ductivity, is stated to be among the results of Prof. Graham Bell’s recent researches, but only at temperatures below that at which it becomes dark and viscid. Incandescent Electric Lights have been made successfully by Mr. Swan, of Newcastle-on-Tyne. The material used by him is a wire of dense and elastic carbon, made by a process which has not yet been disclosed. Each is about three inches long, about of an inch in diameter, and so light as to weigh only from to of a grain. Their durability is remarkable, as he states that lamps have been continuously lighted by them for over three months at a time, with an intermission of only three weeks. The light varies in intensity from 30 to 50 standard candles. Thirty-six such lamps were exhibited at his lecture, working from a dynamo-electric machine driven by a four horse-power engine. At a previous lecture, twenty lamps gave more light than the seventy-six gas jets usually supplying the room. Fitzgerald1 s Magneto- andDynamo-Electric Machines. — The improvements in magneto- and dynamo-electric machines, the invention of Mr. Desmond G. Fitzgerald, deserve careful attention, inasmuch as they show a decided advance in the right direction. The main idea of the inventor seems to have been to aim at perfecting the Gramme machine ; and so, instead of rotating the ring between the poles of a magnet on the ordinary system, he wholly or partially surrounds the ring both longitudinally and transversely, thus increasing the effective inductive action. The ring is thus magnetized directly, and with the least possible loss, and the direction of the inducing magnetic polarity is in the circle constituted by the ring itself, as it should be. Considerable modifications are made in the construction of the ring. Ordinarily, in winding a number of coils of wire upon a ring, more especially if it be of circular section, and if the number of turns of wire be the same in each layer, interstices are left between the coils. These interstices are filled by Mr. Fitzgerald with soft iron wedge-shaped blocks. These blocks can either be made with the ring, or separately, and slipped on, the ring being made in halves to receive them. The Metric System. — There has lately been some agitation in the United States as to the advisability of rendering the Metric System compulsory for 90 POPULAR SCIENCE REVIEW. public use. It was legalized in May, 1866, and since then several societies have been organized to teach its principles. Mr. Coleman Sellers, the well-known mechanical engineer of Philadelphia, argues in opposition that the inch is the resting-place or starting-point in the memory in all machine-shops where English is spoken, in Russia, generally in Germany, and possibly, though not always knowingly, in France. The inch is conveniently subdivided by a process of halving which provides the mechanic with all the sizes he needs, and which he finds ready to his hand in merchant goods. But Mr. Sellers goes further : he compares the inch with the millimetre in all the processes of the workshop, and shows how much superior is the inch or system of halving to that which the metric system compels us to adopt. For drawings made on the metric scale only seven sizes can be utilised — viz. full, half, one-fifth, one-tenth, one-twentieth, one- twenty-fifth, and one-fiftieth. With a good 2ft. rule, we can obtain twelve sizes — viz. full, half, third, quarter, sixth, eighth, and so on up to sixty- fourth, and to these can be easily added five of the others where the rule is also decimally divided, as good rules mostly are. There are thus seventeen sizes instead of seven for use with the inch-divided rule ; but in drawing, the scales in most common use are one-half, one-fourth, and one-eighth, which in rapid drawing can be easily raised by taking diameters from one drawing and using them as radii in the other- -a process impossible between one-half and 1-5 sizes. The true value of the extended series of scales is manifest to any one familiar with both, and what is remarkable is that draughtsmen brought up to metric scales take very kindly to the inch scale and prefer it. The great majority of sizes used in any machine, large or small, are less than one metre ; and to avoid the errors likely to occur with decimals, the French or German mechanic uses the millimetre, writing 8mm. rather than ’008m., and the unit thus fixed is preserved until the larger parts are figured by perhaps many thousand millimetres, and these figures have to be squared and cubed with much multiplication, which would be saved by the use of the inch, the foot, and yard. With the use of the English measures, we complete the calculation sooner, because we are able to deal with the largest measures compatible with convenience ; ‘ we can use the cubic inch, the cubic foot, or the cubic yard at our pleasure, just as the mechanic selects his tools in accordance with the extent of his work, and does not waste time driving at a railroad spike with a tack-hammer.’ Mr. Sellers tells us he has tested the metric system in both drawing-office and machine-shop, and has been disappointed : ‘ an incorrectly figured drawing costs nothing on account of errors so long as it rests quietly in its drawer, but it costs fearfully when the error is discovered in the partially finished machine.’ Messrs. Sellers have in one branch perfected an organization based on the metric system, and they have no intention of giving it up — precisely for the same reason that they will not change their older scales. As mechanics they recognize the fact that those who had the making of the metric scale began at the wrong end — the big end of the scale — the size of the world, and the units it has been cut into are found inconvenient in their shops, however convenient they may be for calculating in merchants’ ledgers. — Enylish Mechanic. Researches of Mr. E. II. Mall. — As a new action of magnetism on a SCIENTIFIC SUMMARY. 91 permanent~electric current have already been described in this Summary, its direction was evidently a matter of fundamental importance. Prof. Rowland predicted that the direction would be reversed in paramagnetic iron from that found in diamagnetic gold, and experiment has verified the prediction. Mr. Hall finds, however, that nickel and platinum — both magnetic substances — resemble, not iron, but gold. The fact has to be taken into account in endeavouring to apply the newly-discovered action to explain the magnetic rotation of the plane of polarization in accordance with Maxwell’s electromagnetic theory of light. He has, therefore, repeated Kerr’s experiment on rotation by reflexion from the pole of a magnet, using nickel for the latter instead of iron. The disc was placed between the poles of an electromagnet. The action on the plane of polarization, though ap- parently much weaker than in iron, was unmistakably in the same direction. Prof. Hopkinson, in a note contributed to the Philosophical Magazine , shows that what Clerk-Maxwell calls the ‘ Rotatory co-efficient ’ completely expresses the important facts discovered by Mr. Hall. Of this co-efficient Maxwell says, 'We have reason to believe that it does not exist in any known substance. It should be found, if anywhere, in magnets which have a polarization in one direction, probably due to a rotational phenomenon in the substance.’ The passage affords another remarkable instance of theoreti- cal prediction, afterwards confirmed by experiment. The Velocity of Sound in Gases has been very comprehensively compared by Herr Hilfer. He divides the methods into three groups : — I. Theoretical methods (a) from wave-theory : results for air, V. = 280 m., with correction, 331*88 for 0° : (6) from the kinetic theory of gases, equal to 2 8 — 27 r o or of the mean value u of molecular velocity : result = 323*33 O 7T — Z or 322*47 ; with correction on account of duration of collisions, 332 m. : (c) from a combination of the formulae of wave-motion, and of the gas-theory ; result = 331*94. II. Direct experimental methods , in some of which, with length known, time is measured, either in open space or in tubes ; in others, with time given, distance traversed : results, excluding the older experiments : — French Com- mission (1822) = 331*2 ; Moll and Van Beek (1823) =332*25: correction by Schroeder van der Kolk = 332*77 ; Regnault (1868) = 330*6 ; Le Roux, = 330*66 ; Szathmari, by method of coincidences = 331*57. IH. Indirect experimental methods, from wave-length : (a) by measure- ment of the length of pipes ; (6) by observation of dust-waves ; (c) by means of interference tubes ; ( d ) from coincident vibrations of two manometric flames: results, Wertheim =331*33; Zoch(1866) =332*65. — Png. Mechanic. The Dependence of Thermoelectric Currents on the Gases in contact with the Terminals having been asserted by Exner, Prof. C. A. Young has pro- duced a test experiment on the point. An exhausted glass tube contained an iron wire with platinum terminals, which were again fastened to iron wires leading to a galvanometer. The tube was exhausted to one-millionth of an atmosphere. On laying the apparatus in sunlight, and alternately shading the internal or external junctions, an electromotive force could be produced which was found to be equal in every case. He considers this to negative Exner’s statement. 92 POPULAR SCIENCE REVIEW. Rotatory Magnetic Polarization in Oases forms the subject of along paper in the Annales de Chimie etde Physique, by M. H. Becquerel. The principle has already been described. In the present paper a minute account is given of the apparatus employed, and the precautions adopted to insure accuracy. The apparatus consists of two distinct parts, (1) the optical, (2) the mag- netic. The gas was contained in a tube 3 *27 metres long, closed by parallel glass ends. Around, but not touching, this are six large coils, each contain- ing 15 kilogrammes of wire, or about 90 kilogrammes in all, with a length of 1380 m., when joined in a continuous series. The current used was from 80 nitric acid batteries of large size, in two series of 40 each. Under so powerful a current, the conductors and the tube itself soon became warm, rising to a temperature of 40° Centig. or 102° Fahr. To estimate variations in the cur- rent from this cause, and also from changes in the battery, a sine-galvano- meter was placed in a shunt from the main circuit, and a curve plotted from its indications. The quantity of gas operated on amounted to about 37 litres. It acted of itself as an air-thermometer by means of a pressure-tube. The amount of rotation being very small, only about 5' of angular measure with an inverted current, it was found expedient to amplify it by the method of reflection used by Faraday and Foucault. Magnetic rotation is known to be proportional to the path traversed, in whatever direction it may pass. The source of light was lime, passed, in some instances, through coloured dia- phragms. The polarizer was a large Nicol’s prism, giving a beam over an inch in diameter. By means of two plane mirrors silvered in their middle part, the ray to be polarized was passed three, five, seven, or nine times along the length of the tube before being received on the analyzer. This consisted of a Foucault’s prism mounted on a divided circle with a vernier reading to minutes of arc. Four double reflections, with nine passages of the ray through the tube, were generally employed. The current being passed in one direction the two images were brought to similar tint ; and the current being then reversed, the analyzer was turned to similarity, and the angle read off, giving double the magnetic rotation for the substance experimented on. The necessary corrections for various causes of error were referred to bisul- phide of carbon, the rotatory power of which is large. Besides temperature and magnetic intensity named above, there were, the displacement and want of homogeneousness in the source of light, rotations caused by the glasses, lenses, and mirrors of the apparatus, — all these are discussed at length and tabulated. A remarkable relation is shown between the index of refraction of a gas and its power of magnetic rotation. Oxygen, however, forms a notable exception. ZOOLOGY. A New Form of Cystic Worm. — M. A. Villot, who some time since described a peculiar cystic worm (- Staphylocystis ), parasitic upon Glomeris limhatus , has discovered another new form in the same myriopod, which he notices ( Comptes Rendus, 6 December, 1880) under the name of TJrocystis prolifer. It is a very minute creature, measuring only 0*09 millim. (less than eh> inch) in length : and one remarkable circumstance about it is that it SCIENTIFIC SUMMARY. 93 resides in the same host in two stages of its development — namely, as the true cystic worm in the visceral cavity of the Glomeris; and in the scolex state, encysted in the adipose tissue of the same animal. M. Villot describes the parasite as consisting of three distinct parts, which he calls head, body, and caudal vesicle. The head is oval, truncate in front, and furnished with four sucking discs, and with a long trunk. The latter is invaginated in the head, which in its turn is invaginated in the body, and this again in the caudal vesicle. The invagination of the trunk forms a funnel-like hollow at the apex of the head, and the inner wall of the latter is armed with a circlet of excessively minute hooks, ytuv inch long. The multiplication of the worm in the cystic stage is effected (as we understand the statements of the author) by budding at the posterior extre- mity of the caudal vesicle, and the buds are usually thrown off as soon as they are perfectly formed, so that the colony rarely consists of more than two individuals. The scolex formed in the hud, which remains during its final development attached to the parent worm by a thin pedicle, seems to resemble that of the parent in all respects; when detached it speedily throws off the enclosing vesicle, and proceeds to encyst itself in the adipose tissue of the host, still invaginated in the so-called ‘body.’ The further development of this worm is still unknown ; it probably takes place in some Alpine bird or mammal, the cystic worms having been obtained from a Glomeris collected in the woods of the Grande Chartreuse. The Discomedusce. — Prof. Hackel has read before the Medical Society of Jena a memoir on the organization and classification of the Discomedusae, a group which he defines as including all those Acraspeda which, in their youth pass through the well-known ontogenetic larval form of Ephyra ( Ephyrula ), as represented by the first free-swimming product of the division of the so-called Hydra tuba. These may be regarded in accordance with the ‘ biogenetic fundamental law,’ as all phylogenetically derivable from an original common stock-form, resembling JEphyra : Ephyrcea. — This common starting- form of all Discomedusae possesses eight sense-organs (4 per-radial and 4 inter- radial), and alternating with these 8 adradial tentacles, and intercalated between the former and the latter 16 marginal lobes. The umbrella of all Discomedusae is shallow and discoidal, and their sexual glands are developed by centripetal growth in the subumbral stomachal wall. The great number of new Discomedusae which the author has had the opportunity of examining during the last few years have led him to form a new classification of the group. He distinguishes in it three sub-orders and ten families, characterized as follows - Sub-order 1. — Cannostom^e (Tubular-mouthed Medusae) : Mouth-tube simple, without buccal tentacles. Central mouth simple, square. Radial pouches, without an annular canal. Either 4 or 8 gonads (reproductive organs). Tentacles solid, usually short. Families. — 1. Ephyeid-® : Radial sacs broad, simple, without ramified distal canals, without an annular canal. — Subf. 1. Palephyrida, with 8 sense- organs and 8 tentacles, with 4 horseshoe-shaped interradial gonads. — Genera, Ephyra, Palephyra, Zonephyra. — Subf. 2. Nausithoidce, with 8 sense-organs and 8 tentacles, and 8 separated adradial gonads. — Genera, Nausicaa, Hausi- thoe, Nauphanta : Subf. 3. Collaspidce, with from 16 to 32 sense-organs, and 94 POPULAR SCIENCE REVIEW. an equal number of tentacles, with 8 separated adradial gonads. — Genera, Atolla, Collaspis. Family 2. Llnergid.®. — Radial sacs broad, with branched, ccecal distal canals, without annular canal. — Subf. 1. Linanthida, with 4 interradial, horseshoe-shaped gonads. — Genera, Linantha, Linergis : Subf. 2. Linuehidce, with 8 separated adradial gonads. — Genera, Liniscus, Linuche. Sub-order II. — Semostomje (Yane-mouthed Medusae) : Mouth-tube divided into 4 per-radial, folded buccal arms. Central mouth simple, cir- cular : sometimes broad radial sacs, without annular canal ; sometimes narrow radial canals, with an annular canal : always 4 gonads. Tentacles hollow, generally long. Family 3. Pelagid.®. — Radial sacs broad, simple, without branched distal canals, without annular canal. — Genera, Pelagia , Chrysaora, Dacty- lometra. Family 4. Cynaneid^e. — Radial pouches hroad, with branched, coecal distal canals, without annular canal. Subf. 1. Medoridce , with 8 sense- organs, — Genera, Procyanea, Medora, Stenoptycha, Desmonema, Cyanea, Dry - monema : Subf. 2. Pateridce , with 16 sense-organs. — Genera, Patera , Melusina. Family 5. FlosculidvE. — Radial canals narrow, simple, unbranched, with an annular canal. — Genera, Floscula, Floresca. Family 6. Ulmaridje. — Radial canals narrow, all, or part of them, branched, with annular canal. Subf. 1. Umbrosidee, with marginal tentacles, which are inserted on the margin of the umbrella between the marginal lobes, — Genera, Ulmaris, Umbrosa, Undosa. Subf. 2. Sthenonidce, with sub- umbral tentacles, which are inserted upon the ventral side of the velar margi- nal lobes, at a distance from the margin of the umbrella, — Genera, Sthenonia, Phacellophora. Subf. 3. Aurelidce with exumbral tentacles which are in- serted upon the dorsal side of the velar marginal lobes, remote from the margin of the umbrella, — Genera, Aurelia , Aurosa. Suborder III. Rhizostomje (Root-mouthed Medusa). -Mouth-tube re- placed by 8 adradial root-like buccal arms with numerous suctorial mouths. Central mouth obliterated. Radial canals narrow, always branched, with an annular canal. Gonads always 4 (never 8 !) Tentacles absent. Family 7. Toreumid.®. — Four subgenital cavities, separated, the bran- chial disc forming the floor of the stomach ; suctorial fringes of the buccal arms only ventral, on their axial surface, — Genera, Archirhiza, Cephea, Diplo- pilu8, Polyrhiza , Cassiopea, Polyclonia , Toreuma. Family 8. Pilemidje. — Four subgenital cavities, separated, branchial disc forming the floor of the stomach, suctorial fringes of the buccal arms dorsal and ventral, both on their axial and abaxial surfaces, — Genera, Pilema, Furhizo8toma, Stylonectes, Toxoclytus , Phyllorhiza, Stomolophus. Family 9. Versurida:. — Four subgenital cavities, united to form a cen- tral portico ; hence the floor of the stomach and the branchial disc are separated ; suctorial fringes of the buccal arms only ventral, on their axial surface, — Genera. Haplorhiza , Cotylorhiza , Octostyla, Crossostoma, Versura. Family 10. Crambessid^:. — Four subgenital cavities, united to form a central portico, hence the floor of the stomach and the branchial disc are SCIENTIFIC SUMMARY. 95 separated ; suctorial fringes of the buccal arms dorsal and ventral, both on the axial and abaxial surfaces, — Genera, Leptobrachia, Thysanostoma, Masti- gias, Himautostoma, Phacopilus , Catostylus, Crambessa. The comparative anatomy and ontogeny of the Discomedusae enable us approximately to recognize very clearly the phylogeny of the ten families. The common stem-group of the whole order is formed by the Cannostome family Ephy ridae, with the stem-genus Ephyra ( JEphyrcea ) . From this, first of all, two divergent families were developed : — the Linergidae and the Pelagidae. The latter form the stem-group of the Semostomae, and split into the two families Cyaneidae and Flosculidae, from which last proceeded the TJlmaridae, and from these again the Toreumidae, the stem-group of all the Bhizostomae. The two families, Pilemidae and Versuridae, are probably divergent branches of the Toreumidae, while the Crambessidae have probably originated from the Versuridae (but perhaps also from the Pilemidae). This phylogenetic hypothesis is displayed by Prof. Hackel in the following genealogical tree : 8. Pilemidae. 10. Crambessidae. 9. Versuridae. i 7 4. Cyaneidae. 2. Linergidae. 7. Toreumidae. 6. TJlmaridae. 5. Flosculidae. i j 3. Pelagidae. 1. Ephyridae. Ephyra. ( Kosmos , October , 1880.) Classification of the Pennatulida. — In his report on the Pennatulida col- lected during the voyage of the Challenger , Prof. Kolliker proposes the fol- lowing new classification of those curious Polyps : Order PENNATULIDA. I. Rhachis with a bilateral arrangement of the polyps. A. Rhachis elongated, cylindrical. AA. With pinnules or leaves .... Sect. I. PENNATULEiE. * Pinnules well developed .... Subsect. 1. Penniformes. a. Zooids situated on the pinnules . Fam. 1. Pterocididae. Genera, Pteroeides, Herkl., Godefroyia , Koll. Sarcophyllum, Koll. 96 POPULAR SCIENCE REVIEW. b. Zooids on the ventral and lateral sides of the rhachis .... Fam. 2. Pennatulidae. Genera, Pennatula, Lam., Leioptilum, Verr. Ptilosarcus, Gray, Halisceptrum , Herkl. t Pinnules small Subsect. 2. Yirgularieje. a. Pinnules without a calcareous plate Fam. 1. Yirgularidae. Genera, Virgularia, Lam., Scytalium , Herkl. Pavonaria, Koll. b. Pinnules with a calcareous plate Fam. 2. Stylatulidae. Genera Stylatula, Yerr. Dubenia, Kor. and Dan. Acanthoptilum , Koll. BB. Rhachis without pinnules, polyps sessile Sect. II. SPICAT^E. a. Polyps on both sides of the rhachis in distinct rows Subsect. 1. Funiculineje. aa. Polyps with cells. a. No ventral zooids .... Fam. 1. Funiculinidae. Genera, Funiculina, Lam., Halipteris , Koll. (3. With ventral zooids . . . Fam. 2. Stachyptilidae. Genus, Stachyptilum, Koll. b. Polyps on both sides of the rhachis in a single series, or in distinct rows .... Subsect. 2. Junciformes. aa. Polyps without cells. a. Polyps large. aa. Rhachis elongated, cylindrical . . . Fam. 1. Kophobelemnonidse . Genera Kophobelemnon , Asb., Sclerobelemnon, Koll., Bathyptilum, Koll. /3(3. Rhachis short . . Fam. 2. Umbellulidse. Genus Umbellula, Lam. (3. Polyps small .... Fam. 3. Protocaulidse. Genera, Protocaulon, Koll., Cladiscus, Kor. and Dan. bb. Polyps with cells . . . Fam. 4. Protoptilidae. Genera, Protoptilum, Koll., Lygomorpha , Kor. and Dan., Microptilum , Leptoptilum, Trichoptilum and Scleroptilum, Koll. B. Rhachis expanded in the form of a leaf. Sect. II. RENILLEH3. Fam. 1. Renillidae. Genus, Renilla, Lam. II. Rhachis with a radiating arrangement of the polyps Sect. III. VERETILLEiE. A. Calcareous bodies long Fam. 1. Cavernularidae. Genera, Cavemularia , Val. Stylobelemnon, Koll. AA. Calcareous bodies short .... Fam. 2. Lituaridae. Genera, Lituaria , Yal., Veretillum , Cuv. Policella, Gray, Clavella, Gray. Cr/Jfuai.L VA j-oLj /*$/< Twelfth Thousand. Demy 4to. boards, price 5$. HUMOURS WITH THE STARS A Plain and Easy Guide to the Knowledge of the Constellations. SHfriNG IN TWELVE MAPS THE POSITION OF THE PRINCIPAL STAR-GROUPS NIGHT AFTER NIGHT THROUGHOUT THE YEAR. VI 1 INTRODUCTION AND A SEPARATE EXPLANATION OF EACH MAP. By R. A. PROCTOR, B.A., F.R.A.S. 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The Lenses are set in ebonite cells, and mounted in tortoiseshell frames/ , Price of the Platyscopic Lens, mounted in Tortoiseshell, magnifying either 15, 20, or 30 diameters, 18s. ILLUSTRATED DESCBIPTIOU SIEUsT T PREE. JOHN BROWNING, 63 STRAND, LONDON, W.C. BROWNING’S PLATYSCOPIC Browning’s Pocket Microscopi The New Pocket or Field Microscope, on firm folding brass tripod stand, with fine adjustment, 1 inch objective, large field oy e-piece, hand-pliers, etc. Height when set up, 10 inches; dimensions, packed in morocco case, 5| inches long. Price £1 1U 6d. List of Microscopes sent free. Illustrated Catalogue of Microscopes, with 41 Illustrations, 10 whole page Illustrations, sent for Six Stamps. JOHN BROWNING, Optical and Physical Instrument Maker to H.M. Government , the Royal Society, the Roy Observatories of Greenwich , Edinburgh, <(-c. (Cr. 63 STRAND, LONDON, W.C. The Publisher will mail this Journal to any Address in the United State', for one year, on receipt of Post Office Order for 11s. No. 18. Series. April 1881. [2s. 6d. THE POPULAR EDITED BY W. S. DALLAS, F.L.S. Assistant-Secretary of the Geological Society . CONTENTS. The Myxomycetes or Mycetozoa ; Animals or Plants P By W. Saville Kent, F.L.S., F.Z.S., F.R.M.S. (Illustrated.) The Permanence of Continents. By j. Starkie Gardiner, f.g.s. Preliminary Note on the Existence of Ice and other Bodies in the Solid State at Temperatures far above their ordinary Melting Points. By Thomas Carnelly, D.Sc., Professor of Chemistry in Firth College, Sheffield. (Illustrated.) On the Former Existence of the Roe-Deer in England. By J. E. Harting, F.L.S. , F.Z.S. Contributions to the Knowledge of the Hottentot Race. By M. J. A. Roonda Smit. REVIEWS. Animal Life — A Polar Reconnaissance — Helmholtz's Lectures — Nature’s Hygiene — Physiological Chemistry — The Constitution of the Earth — Steam and the Steam-Engine — Extinct British Animals — The Christian Knowledge Society — Plant Life — Movements of Plants. SCIENTIFIC SUMMARY. Anthropology — Astronomy — Botany — Geology and Palaeontology — Physics — Zoology. ILLUSTRATED. LONDON : DAVID BOGTTE, 3 ST. MARTIN’S PLACE, TRAFALGAR SQUARE. LONDON : FEINTED* BY STRANGEWAYS AND SONS, TOWEE STREET, UPPER ST. MARTIN’S LANE. le First Series, edited by Dr. H. Lawson, may be had complete in numbers, price £7 12s. 6d. ; or, 15 Volumes, in cloth, £9 2s. in half-morocco, £11 8s. F. & C. OSLER, Glass Dinner Services. Glass Dessert Services. Glass Table Decorations. Glass Flower Vases. Glass Table Lamps. Glass Lustres & Wall Lights. Glass & Metal Chandeliers. China Dessert Services. China Dinner Services. China Breakfast Services. China Tea Services. China Vases. 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( FTJLIG 0 = jETHALIUM) LYCOGALA ARCYRIA. 11 ! f4i • i y % mmj 1 x^i l * tv ' Pop. Sci.Eev.N.S.Vol.V. PI. EL. W Scarce KmtdY Yr.E/ied*. Mint^mBrc5 MYCETOZOA, 97 THE MYXOMYCETES OR MYCETOZOA; ANIMALS OR PLANTS? By W. SAYILLE KENT, F.L.S., F.Z.S., F.R.M.S. [Plates III. and IV.] ALONG- the lower confines of the organic world diverse group-forms are to be encountered, of which it is hard to predicate whether they rightly appertain to the animal or to the vegetable series. Prior to that deeper insight into the mysteries of Nature that, thanks chiefly to the improvements, made in the compound microscope, has fallen to the lot of the present generation, organisms of even large appreciable dimen- sions— such as Sponges, Corals, and Zoophytes — furnished sub- jects of contention between Zoologists and Botanists. Before the rapid advance of modern science, however, the lists for controversy have been gradually growing more and more con- fined, further progress at the same ratio threatening ere long to place the biologist in the position of the classic hero, who wept for the want of other worlds to conquer. Already, the cordon drawn around the once extensive tourney-ground includes only the lower groups pertaining to Cryptogamic Botany and to that subdivision of the animal kingdom most usually defined by the title of the Protozoa, but which might, with equal con- sistency, be designated the department of Cryptogamic Zoology. All of. these agree with one another, and at the same time differ from the more highly organized groups of Phanerogamic plants and Metazoic animals respectively in the obscure and comparatively rudimentary character of their reproductive phe- nomena. In recognition of the extreme difficulty that attends the pre- cise definition of an arbitrary boundary line that shall, to the satisfaction of both Botanists and Zoologists, separate the sub- jects of their respective studies, Biologists have from time to NEW SERIES, VOL. V. NO. XVIII. H 98 POPULAR SCIENCE REVIEW. time proposed the institution of an intermediate kingdom or neutral territory for the reception of all those doubtful organic forms which with more or less justice have been shifted from one side to the other of the barrier-line in accordance with the strength of the evidence adduced. Thus, Mons. Bory de St. Vincent originally instituted for the inclusion of such debatable types his Le JRegne Psyehodiaire ; and thus Prof. Ernst Hackel, scantily acknowledging, perhaps, Bory’s lead, has quite recently substituted in its place, his so-called kingdom of the ‘Protista/ w’hich, in accordance with its founder’s views, in- cludes the following divisions : — Kingdom Protista , Hacked. Generic type. Class 1. Monera . . . . Protomyxa. 2. Lobosa . . . . Amoeba. 3. Flagellata . . . jE 'uglena. 4. Catallacta . . . Magosphcera. 5. Labyrinthulae . . . Labyrinthula. 6. Diatomeae . . . Navicula. 7. Myxomycetes . . . JEthalium. 8. Khizopoda . . . Gromia. As already pointed out by the writer in A Manual of the Infusoria, Vol. i. p. 44 et seq., October, 1880, the recognition of such a proposed neutral territory or kingdom by no means lessens, but simply enhances, the pre-existing difficulty. For in place of the simple boundary-line that had formerly to be defined between animals and plants it necessitates the definition of two such lines — the one between the Protista and the lower animals, and the other between that group and the lower plants. Furthermore, as demonstrated by the writer in this treatise, there is scarcely one out of the eight class divisions included in this newly proposed kingdom that cannot be relegated wTith absolute certainty to one or the other of the two older primary divisions. Several of these groups, again, are most artificially constructed. The class Monera is well-nigh obsolete. Formerly proposed by IJackel for the reception chiefly of the Foraminifera and certain Protozoa, in- cluding Bathybius (?), in which the presence of a nucleus or endoplast had not been detected, a few obscure amcebiform organisms alone remain to sustain its titular reputation. The Lobosa, as a class separate from the ordinary Bhizopoda, cannot be consistently recognized ; while the so-called Catallacta, including the single genus Magosphcera, may be appropriately likened to a colonial form of such a multiflagellate Infusorium as Ijophomonas. Taken as a whole, six out of the eight classes enu- merated in the foregoing list conform in all essential points with THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS ? 99 that formula of organization distinctive of the lowest or Pro- tozoic section of the animal kingdom. Of the two residual groups, that of the Diatomeao as assuredly belongs to the vege- table series ; one only being finally left, of which it may be said that opinions are substantially divided as to their animal or vegetable affinities. It is with this single section, No. 7, or that of the Myxomycetes, that this article purposes to deal. The Myxomycetes, Myxogastres, or Mycetozoa, as they have been variously designated, have up to a very recent date remained undisturbed within the precincts of the vegetable kingdom, being accepted on all hands as constituting a subor- dinate, though somewhat abnormal group of the Gastero- myeetous Fungi. The diagnosis of the order, as given in M. J. Berkeley’s Introduction to Cryptogamic Botany , 1857, and repro- duced in other English text-books of Mycology, runs as follows : — ‘ Whole plant at first gelatinous. Mycelium often vein-like , forming reticulated or anastomosing strata, but sometimes diffuse, giving rise to sessile or stipitate, free or confluent peridia , consisting of one or more membranes, enclosing, ichen mature, a dry mass of threads or plates, and spores; at length often bursting. Threads of various structure, sometimes containing one or more spirals .’ Mr. Berkeley further proceeds to say (l.c. p. 336), — 4 This is, perhaps, one of the most remarkable groups of Fungi, and at present one on which we have least information. In their early stage they consist of a pulpy or cream-like mass, collected in distinct globules, or creeping over its matrix in the form of branched anastomosing veins. In this stage the tissues are so delicate that they exhibit no structure, and if hardened with alcohol give no further information. From their great fragility when fully grown, and the free dispersion of their dust-like spores, they are with difficulty preserved in an herbarium. But no Fungi afford more elegance of form or singularity of structure according to the nature of the peridium, the flocci, and the disposition of the spores, which are their three main ele- ments. The beauty of form of their peridia is often combined with exquisite colouring, which is sometimes brilliantly metallic, exhibiting tints of steel, gold, copper, or silver, most nearly resembling in this respect very thin membranes met with in the animal kingdom, such as those of the eggs of certain moths. One form, JEthalium septicum, is the pest of hothouses, while a species of Licea, L. per rep tans, sometimes increases with such rapidity in cucumber and melon-frames, as to seriously inter- fere with the culture of these fruits. One marked peculiarity of the Myxomycetes is represented by their indifference as to the matrix upon which they grow. The same species may occur on plants of the most distant natural affinities, and on 100 POPULAR SCIENCE REVIEW. other matrices. One species was observed by Schweinitz to be developed on iron which had been heated in a forge only a few hours previously. Mr. Mclver found one on a leaden tank, while Mr. James Sowerby discovered another on cinders in the outer gallery of St. Paul's Cathedral. Like Algae they appear to derive their nutriment from the surrounding medium, and not from the matrix to which they are attached.' The data embodied in the foregoing and earlier accounts of the Myxomycetes were held to demonstrate their rightful position to be among the Grasteromycetous Fungi, their apparent nearest allies being the Trichogasters or Puffballs, Lycoperdon , JBovista, &c., from which, however, they essentially differed in the pro- duction of their peridia, or sporangia, from a structureless, pulpy mass instead of from a distinct cellular hymenium. (Illustra- tions of the fungus-like, matured peridia or spore-receptacles of various typical representatives of the Myxomycetes, natural size and magnified, will be found in the accompanying Plates III., figs. 1, 21, and 35, and IV., figs. 1, 24, and 30 to 32.) So far, the developmental phenomena of these singular organisms — which among both animals and plants are now universally recognized as furnishing the true key to their natural position and affinities — had remained undiscovered, or involved in the greatest ob- scurity. About the year 1859, however, Dr. A.De Bary, the ac- complished Professor of Botany at Freiberg University, applying himself to the solution of this moot question, arrived at some totally unexpected results. The spores on careful cultivation were found to give rise, not to jointed cellular hyphae, or my- celia, as obtains among all ordinary Fungi, but to flagellate monadiform germs possessing active locomotive faculties, a spheroidal nucleus or endoplast, one or more contractile vacuoles, and the faculty of ingesting solid food-substances. After a short interval these germs, retracting their flagella, assumed an amceboid repent phase and coalescing freely with their neigh- bours, built up the so-called gelatinous, or pulpy masses, out of which the sporangia, or peridia, were developed. With rela- tion to the phenomena exhibited by the Myxomycetes during their active vegetative life, De Bary arrived at the conclusion that they could not be consistently retained as vegetable organ- isms, but were referable to the lower animal series, or Protozoic sub-kingdom, and might be more conveniently designated the ‘ Mycetozoa.’ In the year 1862, the main results arrived at by De Bary were confirmed by L. Cienkowski,* who now for the first time definitely associated with the so-called pulpy mass, derived through the coalescence of the monadiform germs, the title of * Zur Enf/urickeluvgs-geschichte der Myxomyceten, in Pringsheims Jahr - biicher fur wissenschaftliche Botanxk. Berlin, 1862. THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS? 101 the ‘ plasmodium. ’ This plasmodium, taking the form of either a colossal Amoeba, or other Bliizopod, in addition to possessing locomotive faculties and the capacity of ingesting solid food, he further showed to exhibit, in its more extended, ramified con- dition, a distinct circulation or cyclosis of its internal granular elements. Embodying the results of Cienkowski’s investiga- tions with those of his own earlier and more recent researches, De Bary published, in the year 1864, his more extensive account of the Mycetozoa,* which up to the present date is accepted as representing the most complete record extant of the life phenomena of these remarkable organisms. While still in- cluded among the Fungi, perhaps for convenience sake, by systematic botanists, their exceedingly anomalous plan of structure and development has in most instances been fully recognized. No more fitting illustration of the estimate ac- corded to them by this class of biologists is perhaps to be found than the general account of the group included in Julius Sachs’ Textbook of Botany ^ herewith reproduced in extenso : — ‘ The Myxomycetes include a numerous group of organisms which in many respects differ widely from all other vegetable structures, but in the mode of formation of their spores stand nearest to the Fungi, on which account we may treat them as a supplement to that class. The Myxomycetes are remarkable in no ordinary degree from the fact that during the period of their vegetation and assimilation of food they do not form cells or tissues. The protoplasm, which in all other plants is also the general motive power of the phenomena of life, remains in them during the whole of this period perfectly free, collects into considerable masses, and assumes various shapes from the in- ternal force residing in it without becoming divided into small portions which surround themselves with cell- walls, or become cells. It is only when the protoplasm passes into a condition of rest in consequence of being surrounded by unfavourable condi- tions, or when it concludes its period of vegetation by the formation of the reproductive organs — its internal and ex- ternal movements ceasing at the same time — that it breaks up into small portions which surround themselves with cell-walls, and which even then never form a tissue in the proper sense of the term. The Myxomycetes live upon decaying and rotting vegetable substances. While endowed with motion, they either creep over the surface of the substratum or live in hollows and pores in its interior, but for the purpose of reproduction they always come to the surface. When entering on the repro- * Die Mycetozoen ein Beitrag zur Kenntniss der niedersten Organismen. Leipzig, 1864. t English edition, translated by A. W. Bennett and W. T. Dyer. London. 1875. 102 POPULAR SCIENCE REVIEW. ductive condition, tlie entire protoplasmic substance, plasmo- dium, becomes transformed into sporangia or larger receptacles. In JEthaliiwi septicum , the so-called “ flowers of tan,” tbis spore- receptacle is represented by a cake-like mass, not unfrequently measuring a foot in length and breadth and over an inch in thickness. The inside of the cake is dark-grey, easily pul- verized, and penetrated by yellow veins consisting of tubes interwoven in all directions. The skin, or cortex, consists of densely interwoven, irregular bundles of tubes connected in a peculiar manner, and containing an immense number of cal- careous grains as well as a yellow pigment. JEthalium, in its plasmodium condition, is able to creep away from the tan upon which it was originally growing, and, climbing up neighbouring plants to the height of several feet, accumulates upon their leaves. The monadiform germs developed from the spores are, under unfavourable circumstances, transformed into microcysts ; when dry they remain in this state for months, reverting again to the mobile form when placed in water. The young plasmodia are also capable, under like conditions, of forming cysts out of which they again creep on the return of warm, moist weather. The more matured plasmodia may likewise enter upon a temporary state of rest, — sclerotium. First drawing in its arms or outlying ramifications, it next assumes a sieve-like contour or becomes resolved into a mass of irregular nodules, and the whole substance breaks up into a large number of round or polyhedral cells. When placed in water, the cell- walls again become absorbed, and the sclerotium reverts to the condition of a mobile plasmodium. Finally, the plasmodium having attained its full growth, a fine membrane, or pellicle, is formed over its surface and the interlacing capillitium and spores within, the lime contained within the plasmo- dium being deposited in the form of granules on the capil- litium or wall of the sporangium. The passage to this reproductive phase is accomplished with great rapidity,— two hours only being quite sufficient, in the case of JEthalium, to convert a soft mobile plasmodium into the motionless, cake-like sporangium. The water previously contained in the plas- modium is partly expelled in the fluid state, while the residue speedily evaporates/ Upon the data included in the foregoing epitomization of the structure and life history of the Myxomycetes, and more especially with regard to those that relate to their earlier loco- motive and ingestive faculties, it is not to be wondered at that many biologists have come to look upon their association with vegetable organisms as no longer tenable, and to decide that their nearest allies are to be sought for among the animal series. Such an opinion was freely expressed by Prof. Allman in his THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS ? 103 Presidential address, chiefly relating to lower organisms, de- livered to the meeting of the British Association for the year 1879. Others, taking an intermediate view of the question, have contented themselves with allotting this group a half-way position in the organic chain, Prof. Hackel, as previously notified, incorporating the Myxomycetes in his newly- established kingdom of the Protista, while Prof. Huxley* remarks of their flagelliferous monadiform germs that ‘ they are embryonic forms of organisms which appear to be as much animals as plants ; inasmuch as in one condition they take in solid nutri- ment, and in another have the special morphological, if not physiological, peculiarities of plants/ Being greatly impressed in favour of the evidence adduced in support of their animal affinities, the present writer has, in a general outline of the sub-kingdom Protozoa, included in Part I. of his Manual of the Infusoria , thought fit to accept the My- xomycetes, or Mycetozoa, as veritable Protozoa, indicating at the same time the very numerous points in which their structural and developmental phenomena tally with those of the more typical representatives of that zoological series. In this manner it was showm that the initial term or flagelliferous unit de- veloped from the spores of these so-called Fungi — possessing a nucleus, contractile vesicle and capacity to incept solid food particles — is in noways distinguishable from an ordinary representative of the genus Monas, as defined by the writer at p. 232 of the Manual quoted. The succeeding or ‘ plasmodium ’ phase of these organisms, likened by its describers to a colossal Amoeba, is similarly correlated by the writer (l.c. pp. 42 and 192) with Labyrintliula, and with the amoebiform masses produced through the coalescence of a greater or less number of primary flagellate zooids, out of which the reproductive gemmules of a sponge-body are built up.^f* The spore-receptacles, or sporangia, are finally interpreted as corresponding on an extended scale with the ordinary encapsuled or encysted conditions of the typical * Anatomy of Invert ebrated Animals, p. 44, ed. 1877. t An additional type, whose adult structure resembles in a remarkable manner the 1 plasmodium ’ condition of the Mycetozoa, is afforded by the Biomyxa vagans, as figured and described by Prof. Leidy in his recently pub- lished Fresli- water Rhizopods of North America, Washington, 1879. This organism, which inhabits the Sphagnum swamps of New Jersey and Penn- sylvania, and may be compared to a shell-less Gromia, protrudes lobate exten- sions, or anastomosing pseudopodia, in every direction, which exhibit a distinct granule circulation, while a greater or less number of contractile vesicles are developed, both upon the surface of the body and along the pseudopodial extensions. The likeness cited as subsisting between these correlated organisms is indeed so great, that Prof. Leidy has some doubts as to whether it represents an immature Mycetozoon or an independent Rliizopod. In one example figured, the central protoplasmic mass is filled with ingested Closteria. 104 POPULAR SCIENCE REVIEW. Protozoa, and also with the hybemating encystments or so-called ‘gemmules,’ or ‘statoblasts’ of Spongilla, and other Sponge types. Further affinities with the Sponges — these organisms being accepted as Flagellate Protozoa — were held to be manifested in connexion with the fine net-work of anastomosing fibres or ‘ capillitium/ singularly resembling the horny rete of the kera- tose Sponges, which is usually developed within the sporangia of the Myxomycetes, and to which are frequently added crystalline or nodular deposits of lime that may be consistently compared with the calcareous or siliceous, spiculiferous elements of ordinary Sponge forms. While it was expected that mycologists, pure and simple, would be somewhat loth to relinquish the interesting little group of Myxomycetes into the hands of the zoologists, it was anticipated that the protest against their advocated transfer would have been raised upon a more substantial basis than that lodged by Dr. M. C. Cooke in his Journal of Cryptogamic Botany, ‘ Grevillea/ for December last. Instead of applying himself to a concise and lucid exposition of those points, which, to his mind, establish, as he expresses it, the ‘ truly vegetable nature ’ of the Myxomycetes, Dr. Cooke confines his criticism of the views advocated by the writer to an unsupported contradiction of the facts accepted as indicative of their animal affinities, accom- panied by what must be objected to as a direct misrepresenta- tion of the arguments used in the practical application of these facts to the question raised. In the first place, it is affirmed that De Bary has entirely abandoned his former views respect- ing the animal affinities of the Myxomycetes. Can Dr. Cooke quote any work or paper in which a renunciation of the facts and opinions expressed in his treatise, Die Mycetozoen , published in the year 1864, is recorded ? This record again being, not as his critic ingeniously affirms, written ‘ in a hurry and repented at leisure/ but representing the result of many years’ careful investi- gation, backed by the confirmation of all essential facts at the hands of an independent authority. The editor of ‘Grevillea’ next politely suggests that, in attempting to correlate the Myxomycetes with the Protozoa, the present writer has ‘ gone out of the way to meddle with a subject that he does not understand,’ that he has no practical acquaintance with the organisms of which he treats, and no knowledge of the later important Polish and other works upon the Myxomycetes, which do not support their animal affinities. Finally, Mr. Saville Kent is accredited with an at- tempt ‘ to squeeze the Myxomycetes into the animal kingdom by stealth ; ’ and to have done this in defiance of axioms he has elsewhere adopted, for the distinction of the ordinary infusorial t\rpes from lower plants, including, more particularly, their capacity to ingest solid food. That the Myxomycetes are en- THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS? 105 duedwith a similar ingestive faculty, Dr. M. C. Cooke practically denies. To the foregoing heavy bill of indictment it is incumbent upon the ^accused to make some brief response. To the one count, that of having based his arguments in support of the animal nature of the disputed group mainly, if not entirely, on the evidence adduced by De Bary and Cienkowski without having then a practical knowledge of the organisms or their more recent literature, the writer must to some extent plead guilty. Such admission must, however, be qualified by the fact of his having a short while since made himself familiar with both the structure and developmental phenomena of various ordinary fungi under able guidance at the South Kensington Biological Laboratory, so that he was not altogether meddling with an unknown subject in pronouncing an opinion upon the claims of the Myxomycetes for association with these Cryptogams. Neither respecting more recent literature can the writer acknowledge himself to have been entirely in the dark. As a subscriber to that work, he possessed, and had re- ferred for further information, to Dr. M. C. Cooke’s Handbook to British Fungi , Yols. I. and II., published in the year 1871, and in which he confidently anticipated finding a masterly, ex- cathedra summary of all that was known concerning the struc- ture and vital phenomena of the Myxomycetan order, with a special reference to the investigations of Continental mycologists. The distinguished compiler of the British Handbook had, no doubt, worked out the problem for himself, and had important affirmative or negative evidence to submit. Alas, for such hopes ! Trace of original investigation there was none, while the latest literature of the subject with which the editor displayed famili- arity was Berkeley’s Outline of an Introduction to Cryptogamic Botany , quoted over leaf, and written fourteen years before (1857). His diagnoses and more general descriptions of the cha- racters of not only the Myxomycetes, but also of the Ilymeno- mycetes, Gfasteromycetes, Coniomycetes, and Hyphomycetes, with those of their leading secondary subdivisions are admittedly copied word for word from that source. The results of the writer’s well-intentioned efforts in pursuit of knowledge, so far therefore as they related to the Handbook of the British Fungi , have to be registered a blank. The serial that enshrines Dr. Cooke’s indignant repudiation of the writer’s furtive attempts to rob mycologists of one of their most interesting- orders kindled hope anew. Though silent as the Sphinx con- cerning the titles of the newer important works, that if consulted would have convinced the writer of the error of his ways, the editor of ‘ Grevillea ’ produces on the cover of his journal a list of his voluminous contributions to Cryptogamic literature, including 106 POPULAR SCIENCE REVIEW. one bearing tbe title of ‘ tbe Myxomycetes of Great Britain. London, 1877/ Here, at length, was a ‘ Daniel come to judg- ment ; ’ here, doubtless, were to be found revealed developmental facts and features undreamt of in tbe philosophy of De Bary and Cienkowski, and by which the writer was to find that the views he advocated respecting the animal nature of these organisms were utterly demolished. The book in question, how- ever, as advertised in ‘ Grevillea,’ hardly fulfils the promise of its title. In place of an original treatise, representing the outcome of many years’ original research on the part of Dr. Cooke, it proved to be a mutilated transcript only of a ‘ monograph of the Mycetozoa,’ published by Bostafinski, in Polish, in the year 1875. As the author naively admits on the title-page, ‘the characters of all the orders, families, and genera, with descrip- tions of the British species and original analytical tables,’ are reproduced word for word from the Continental work ; and since ‘ the Myxomycetes of Great Britain ’ consists exclusively of these translated characters, with two or three pages of editorial introduction, its claim to recognition as an independent treatise as announced in ‘ Grevillea,’ is somewhat doubtful. As a trans- lation, limited only to the diagnoses of the British representa- tives of the group, it furthermore does but imperfect justice to the more comprehensive system embodied in Bostafinski’s Monograph ; and it is therefore satisfactory to know that a complete translation of this work from the Polish into the Ger- man language is shortly announced. Thus much for the external features of the ‘ Myxomycetes of Great Britain,’ but what of the internal ones ? Instead of producing, as the writer anticipated, a complete refutation of De Bary’s and Cienkowski’s observations, Bostafinski not only embodies in his diagnosis of the group the characters of the several developmental stages made known by these two authorities, but also in many instances reproduces their figures in conjunction with his own, and even adopts De Bary’s title, ‘ Mycetozoa,’ in preference to that of Myxomycetes, for the distinction of the group. It needs indeed but to re- produce Dr. Cooke’s translation of Bostafinski’s diagnosis of the order, as given below, to demonstrate this point : — 1 Mycetozoa. De Bary, 1861 ; Bostafinski, 1875. 1 When young, naked, mobile, in consequence of which the masses of plasmodium have a changing form. These masses at the time of fructifica- tion, sometimes dividing themselves into single parts, are transformed into motionless fruits. Fruit either irregular in form ( plasmodiocarp ) or regular ( sporangium ). Sporangia, through fusion and union, produce, now and then, compound fruits ( JEthalium ). iEthalium usually of considerable dimensions, of regular or irregular form, naked, or covered with a common THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS? 107 coat (cortex). Spores produced within the fruit through free-cell formation, or on the surface through division. The contents of the spores at the time of germination give rise to either at first a naked zoospore provided with a nucleus, a cramped (contractile) vacuole, and long cilia, or to an amoeboid. These zoospores, or amoebae, floating together in masses, give rise to mobile plasmodia.’ — Rstfki. Mon., p. 83. The points conceded in the foregoing diagnosis, viz., the derivation of the sporangia from mobile plasmodia, which are themselves built up through the coalescence of a greater or less number of spore-derived amoeboid or flagelliferous units, which are provided with contractile vesicles, and, it should be added, the faculty of ingesting solid food, furnish all that the writer requires for the establishment of their animal nature and affinities. Rostafinski’s systematic monograph, at the same time, deals almost exclusively with the histology and specific distinctions of the sporangia and their contained elements, no data or drawings of their developmental phases being included, beyond such as are evidently derived second-hand from De Bary and Cienkowski. The editor of ‘ Grevillea ’ ignoring the facts adduced by these authorities, denies that the Myxo- mycetes subsist on solid food matter, and has possibly a revelation of his own to disclose. Can it be that he gives adhesion to a novel interpretation of the development of the group placed on record by a Mr. George Massie in the pages of Science Gossip for January 1881, and in which the Myce- tozoon Spumaria alba is represented as producing spores, which give rise to jointed hyphae, after the manner of the typical Fungi? A submission of the drawings of these germinating spores to a mycological expert, resulted, as was anticipated, in the verdict that they had nothing whatever to do with the species to which they were accredited, but represented the adventitious spores of a species of Penicillium , most probably P. crustaceum. Mr. Massie treats the account given by De Bary and Cienkowski of the spores giving exit to motile monadiform or amoeba-like germs as an idle tale, unsupported by correlation with any recognized specific form, and which must vanish into thin air before the weighty proofs adduced through his own original investigation of Spumaria alba. The spores of Fuligo varians (JEthalmm septicum) are also referred to by this writer as giving origin to branching threads, though, unfortunately, the further development of it ‘ was not observed/ Other nameless species are likewise reported by Mr. Massie to have exhibited a similar plan of germination, while not in a single instance out of a number of types experimented upon were mobile cells observed to originate directly from a spore. That Mr. Massie is totally unacquainted with the original records of De Bary and Cienkowski is evident from the fact, 108 POPULAR SCIENCE REVIEW. that in making a quotation from the general account of the Onto- geny of the Myr-etozoa, as elicited by De Bary, delivered by Prof. Allman to the British Association meeting in the year 1869, he remarks : * It is much to he regretted that the Professor should not mention the species presenting such unusual and interesting phenomena.’ Had Mr. Massie consulted the two authorities cited, he would have discovered that the developmental pheno- mena referred to were traced in connexion with no less than twelve well-known species, a list of which is herewith given : — Didymium Libertianum, De Bary = Chondrioderma difforme, Rtfki. Stemonitis obtusata, Fr. = Comatricha Friesiana, Rtfki. Stemonitis fusca, Roth, JEthalium septicum, Fr. — Fuligo varians, Somm. Enerthenema papillata , Bourn. Arcyria punicea, Pers. Trichia varia, Pers. Ly cogala epidendron , Fr. Didymium serpula , Fr. Didymium leucopus, Fr. = Physarum leucopus, Rtfki. Physarum album, Fr. = Condrioderma difforme , Rtfki. Licea pannorum, Wallroth. In the two plates accompanying this article, the writer has further reproduced from the voluminous drawings of MM. De Bary and Cienkowski, their most characteristic illustrations of the developmental phases of some half-a-dozen of the above- named species ; in all of which it is clearly shown that the spores give birth to monadiform germs, out of which, through further development and coalescence, the repent amoebiform plasmodia, and subsequently the fungus-like sporangia, are constructed. Finally, since the Editor of ‘Grevillea’ has determined to repudiate this testimony, he declares that in order to establish the animal nature of the Myxomycetes, it is requisite to produce evidence of a more substantial kind than the mere citation of De Bary and Cienkowski, suggesting in a previous paragraph that the present writer has no practical acquaintance with the organisms under discussion, but has simply ‘ based his theory upon the figures he has observed in illustrated books.’ Unfortunately for this intended overwhelming argument, it happens that even previous to the publication of his views in favour of their zoo- logical affinities, the writer was by no means unacquainted with representatives of this interesting group. Examples of Cratcrium pyriforme (named by Dr. Cooke) and Bcidhamia inaurata, collected some time since and lately examined, assisted him to arrive at the opinion submitted. This examination, admittedly, was restricted to the matured Sporangia and their component elements, the THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS? 109 developmental phenomena being recorded, as duly acknow- ledged, on the strength only of the two Continental authorities. More recently, however, recognizing that greater satisfaction would be derived from a personal investigation of these develop- mental data, a variety of species have been carefully culti- vated with the most substantial results. In addition to the two species above named, the writer has been supplied by Mr. Thomas Brittain, a well-known mycologist of the Manchester district, with authentic examples of Lycogala epidendron, Stemo - nit is fusca, Diaclma elegans, and Physarum tussilaginis. Spores of all were sown in distilled water on ordinary slides, covered with thin glass, and kept, when not under direct examination, in a moist chamber. These were now examined from day to day and hour by hour. In some instances, where the spores had been preserved for too long an interval, germination failed, but in other cases, notably Badhamia inaurata , Stemonitis fusca , and Physarum tussilaginis , an interval of from three or four days to a week has sufficed for the rewaking of their latent vitality and the liberation of the contained germs. These germs in every instance agreed substantially with the figures and descrip- tions given by De Bary and Cienkowski, — the one form, Stemo- nitis fusca, illustrating a type examined by the first-named writer, while the two others represent species of which the develop- mental phases have not been previously described. The phenomena exhibited, as observed by the present writer, while in all cases identical, may be preferentially recorded of Physarum tussilaginis, illustrated by the ac- companying PI. IY., figs. 30 to 55. In this species the spores being of large relative size, — 1 — 2000" to 1 — 1500", those of the other forms averaging but little more than one half these dimensions, — are admirably adapted for cultivation. The power chiefly employed in their more minute examination was a TVth inch objective by Gundlach, with a magnification of from 600 to 1200 diameters ; a lower power, £ inch, sufficing for taking a more general numerical survey. So soon as within seven hours after wetting the spores, or indeed directly follow- ing their deposition on the slide, an examination revealed the companionship of innumerable Bacteria, at present quiescent, with a more or less abundant sprinkling of spores other than those of Physarum, and of considerably smaller size. The pre- sence of these adventitious elements immediately, and not un- necessarily, suggested the desirability of precaution in the regis- tration of subsequent events. The spores specially sown were found, under high magnification, to consist of an outer wall of considerable thickness, finely echinulate externally, and ex- hibiting, by transmitted light, a dark amber or chitinous color- ation. The protoplasmic contents rarely entirely filled the 110 POPULAR SCIENCE REVIEW. outer shell, but remained separated from it by a greater or less number of angular interstices. A central spheroidal nucleus, with a contained nucleolus, one or more large refringent corpuscles, and numerous smaller granules, represented the sum- total of the recognizable internal elements. By the end of the second day active life had already dawned upon the scene. Bacteria were swiftly propelling themselves to and fro in all directions ; one or two biflagellate monads, Heteromitce , whose development was subsequently traced from certain of the smaller spores above mentioned, glided slowly along, dragging their posterior flagella, ‘ gubernacula/ cablewise behind them ; then presently a turn of the stage adjustment brought the observer face to face with a germinating spore, having a slender thread- like hypha. Robinson Crusoe’s feelings, when stumbling upon the naked footprint on the sand, frequently imagined, were moment- arily realized. Were De Bary and Cienkowski in the wrong ? Had they mistaken some of these Heteromitce , or other intrud- ing monads, for Myxoinycetan germs P and did this interesting little group after all dev elope after the manner of a common F ungus ? A little more patience, and the spore from which the hypha emanated was discovered to be entirely distinct from those of the Physarum , and the barometer of our hopes was once more in the ascendant. Sparsely scattered amongst the spores of the Myxomycetan were presently observed, isolated hyaline proto- plasmic spheres having the same diameter and structure as the contents of the spore- cases, just described. In a little while the exit of one of these hyaline spheres from the echinulate spore-cases was witnessed, and the relationship between the two substantially established. By the termination of the third day, these protoplasmic spheres had much increased in number, some of them exhibiting feeble amoeboid movements. An additional factor had, however, now appeared upon the scene in the form of a vermicular monadiform organism (PI. IV., figs. 49 and 50), having a length of 1-1250" to 1-1000", and which progressed somewhat clumsily through the water revolving on its longitudinal axis. A spheroidal nucleus, with its enclosed nucleolus, was observable towards the anterior extremity, and a single rhythmically contracting vesicle at the opposite region of the body. The derivation of these monadiform beings, from the extruded protoplasmic spheres, was immediately suspected, and the correctness of this inference soon substantiated. Selecting an isolated and recently- extruded sphere, it was carefully watched ; and within a space of two hours the entire transformation was gradually accomplished For a considerable interval the newly released germ confined its signs of vitality to a feeble expansion and contraction of its peripheral margin, and to the rhythmical pulsations of its con- THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS ? Ill tractile vesicle, which, as well as the spheroidal endoplast, was clearly discernible. As time progressed, alterations in con- tour were more strongly manifested, though without the germ moving away from the scene of its birth. At length an alto- gether elongate amoeboid, or vermiform aspect predominated, the nucleus or endoplast being shifted to one extremity and the contractile vesicle occupying the other. Then all at once, a flickering at the end containing the nucleus indicated the de- velopment of a flagellate appendage, which in a few seconds became distinctly visible. The vibratile motion of this organ soon caused the body to oscillate and presently lifted it from its hitherto prone position. It now remained adherent only by its posterior extremity, and, in a few more seconds, was launched into the surrounding water a free- swimming, elongate monad. The several successive phases just described will be found illustrated in PI. IV. by the figures numbered consecutively 43 to 48. During the next few days, similar monadiform germs were de- veloped abundantly from the spores in all parts of the field, and the next step in their ontogeny fully certified. It was found in fact that the free-swimming condition of the germs was but of brief duration, and subservient, apparently, only to their local distribution. Within a day or two, sooner or later, the monadiform beings once more betook themselves to a repent mode of existence, the flagella being for a while retained, com- municating to them a remarkable likeness to the repent flagel- liferous animalcules, for which F. E. Schulze has proposed the generic title of Mastig amoeba. The flagella being completely withdrawn, the organisms were now undistinguishable from ordinary Amoebce , and continued to creep about the field by broad, ovate expansions of their periphery, after the manner of those Bhizopods. An important point yet remained to be solved. De Bary and Cienkowski had declared that during both their monadiform and subsequent amoeboid phases, the Myxomycetes ingested and subsisted on solid food matter, figures as given by them in illus- tration of such nutritive faculties being reproduced in PL III., figs. 15, 16 and 45, and PL IV., figs. 12, 13 and 28. This evidence has been regarded by some writers as extremely doubtful, while by others it has been categorically denied. A simple experi- ment, however, soon demonstrated that these two authorities were again completely in the right. Examples, more especially of the repent amoeboid units, had been previously observed, whose bodies contained vacuoles more or less completely filled with ingested Bacteria , which, being produced in numbers prior to the hatching out of the JPhysarum germs, provided for the Mycetozoa an abundant and ready set feast. The common test of adding pulverized carmine to the water, of such value in 112 POPULAR SCIENCE REVIEW. determining the ingestive faculties of ordinary Infusoria, was speedily followed by its free inception by both the natatory mo- nads and the repent amoebiform units, neither possessing a distinct mouth, but the former taking in the particles chiefly towards the anterior region of the bod}q and the latter indifferently at any point of the periphery. As in the case of Bacteria , the smaller particles of pigmentary matter, after inception, were usually collected together within spheroidal vacuoles of the endoplasmic region, and maintained therein the same molecular movements they exhibited in their free condition. The larger particles, on the other hand, remained distributed as more or less distinctly isolated fragments. F or the next few days, and indeed up to the time of going to press with this article — ten days or a fortnight after their exclusion from the spores — these amoeboid organisms have continued to feed and increase in size, many of them measuring twice their original dimensions, and may be said to be fairly started on their way towards the succeeding chapter in their ontogeny, viz. their production through coalescence of the comparatively colossal but still amoebiform * plasmodia/ out of which the spore-receptacles or sporangia are finally evolved. The points now verified, through personal investigation, concerning the development and nutritive phenomena of the Myxomycetes are herewith accepted by the writer as affording the strongest confirmation of his views previously expressed, to the effect that these organisms have nothing whatever to do with Fungi, but are rightly referable to the Protozoic division of the animal series. Among these their correlation may be accomplished with the utmost ease, their entire life- cycle, indeed, being precisely parallel in kind, though differing in degree, with what obtains among the ordinary Flagellate Infusoria. A primary flagelliferous phase, an intermediate repent amoeboid condition, and a final encysted sporiferous state, these three, represent the normal life-cycle of a monadi- form animalcule. § The only essential distinction manifested on the part of the Myxomycetes and which, as just stated, is only one j of degree and not of kind, consists in the fact that the final act, that of encj^stment, and the resolution of the body into | spores, is in this group accomplished by a mass of coalescing or conjugating units, which consequently produce a rela- I tively colossal spore-receptacle or sporangium. — the so-called Fungus — while in the case of the typical Flagellata it is an | isolated monad, or two or a few conjugated units only, that build j up the relatively minute, but otherwise morphologically and physiologically identical reproductive structure. While thus the life-cycle of an ordinary Monad may be declared to be an abbreviated epitomization only of what, when reduced to its THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS ? 113 simplest expression, takes place with the Myxogasters, or as they may he preferably designated the Mycetozoa, this last- named group can undoubtedly claim bonds of affinity with other more complex Protozoa. Thus, as previously intimated, the horny rete or capillitium mostly, hut not always,, developed within the sporangium of the Mycetozoa, singularly resembles the horny network or skeletal elements of the keratose sponges ; while the calcareous concretions also frequently, but not in- variably, developed in intimate connexion with the capillitium and wall of the sporangium, may be similarly compared with the mineral concretions or spicula of the sponges. As certain sponges occur that possess neither a horny rete nor spicula, so Mycetozoa are also to be found having; no mineral concretions, and in which the capillitium is either absent or altogether rudimentary, demonstrating alike in either instance the non- essentiality of these several elements. A case in point illus- trative of the resemblance that subsists- between sponge spicules and the mineral concretions of the so-called Fungi is afforded by the species of Physarum, whose developmental phenomena have just been recounted, and in which, as shown at PI. IV., fig. 35, the minute stellate calcareous bodies scattered over the outer wall of the sporangium, are directly comparable with the minute stellate spicula characteristic of the Sponge group dis- tinguished by the title of the Tethyidse.* In yet another direc- tion the two groups of the Mycetozoa and Spongida may be co-ordinated. The sporangia or spore-receptacles of the first- named class, representing the quiescent state entered upon as the closing act of vegetative life, while morphologically comparable with the encysted phases of the ordinary Flagellate Infusoria, may, in virtue of their essentially compound character, be more correctly identified with the spicule-invested, compound, hiber- nating encystments or statoblasts (Carter), into which many sponge forms, including Spongillci , become resolved on the ter- mination of the season’s growth, and out of which are again liberated the flagelliferous elements that build up anew com- pound sponge-stocks. In conclusion. With those mycologists to whom every spore- capsule is necessarily a Fungus, and whose vision is sealed to every organism beyond their special line of research, the group of the Myxomycetes or Mycetozoa, will doubtless to the end of * It has been maintained by some advocates of the vegetable nature of the Myxomycetes, that these spicule-like structures differ in no way from the crystalline secretions of many plant-tissues known as 1 rhapliides.’ The unsoundness of such an interpretation is however made obvious in connexion with the fact that plant rhaphides are essentially m£n*-cellular secretions, while the spicular elements of both the Sponges and Mycetozoa are as strictly orfra-cellular developments. NEW SERIES, VOL. V. NO. XVIII. I 114 POPULAR SCIENCE REVIEW. time be Fungi still. Embry ological, developmental, and even structural data, are with these taxonomists of no account ; a re- ceptacle containing spores, never mind whence derived, and no matter what it produces, constitutes with them the neplus ultra of what they are pleased to term a Fungus. With the intelligent biologist, however, who approaches the question, familiar with the fundamental structural, and developmental phenomena of other lower organic groups, and who is qualified accordingly to strike a just balance in accordance with the evidence, it is herewith predicated that the days in which these organisms shall be ac- counted Fungi, or even vegetable types, are already numbered. Every successive stage in their life-history, from their first exit from the spore until their final resolution into similar reproductive bodies, may be consistently correlated with those of the typical Protozoa, and with them alone. With the Fungi, on the other hand, their likeness, as manifested only in the matured spore- receptacle, is altogether superficial and illusory. In the pages of ‘ Grevillea’ the writer has been accused of an attempt ‘ to squeeze the Myxomycetes into the animal kingdom by stealth.’ The pre- sent article constitutes in itself, perhaps, the fullest refutation of this charge. The stronger and more intense the light from all sides concentrated upon the question at issue the better. Above all things, moreover, let the light be reflected on the subject by means of the mirrors and condensers of our compound micro- scopes. Let each for himself work out the simple morphological and developmental data that must ultimately decide the point. But before all things let the subject be approached by those possessing so sufficient a practical acquaintance with all cognate organisms as shall forewarn and forearm them against the innumerable pitfalls that will otherwise encompass them on every side. EXPLANATION OF PLATE III. The letters n. and c. v. have the same meaning throughout, signifying , respectively, the nucleus or endoplast , and the contractile vesicle. Figs. 1-20. AZthalium septicum, Fries. Fuligo varians, Somm. ( after De Barg). Fig. 1. Portion of margin of ripe sporangium showing crust-like outer wall and internal spore mass, natural size. Fig. 2. Fragment of internal, horny network, or ‘ capillitium/ x 390. Fig. 3. Three isolated spores, x 390. Figs. 4-7. Amoehiform germs being liberated through the rupture of the spore-wall ; that at 7 entirely free, x 390. Figs. 8-11. Successive flagelliferous or monadiform phases of the same germs. Pop. Sci.Rev.N. S. Vol. V. Pl.JV' ( DIDYMIUM.) CV -tis* (PHYSAHUM.) r747 Am rvj A v,6;J \y @r MYCETO ZOA. THE MYXOMYCETES OR MYCETOZOA ; ANIMALS OR PLANTS P 115 Figs. 12-14. More advanced germs which have again assumed the repent amoeboid state, x 390. Fig. 15. A small repent 1 plasmodium/ produced through the further development and continuance of a number of the preceding amoeboid units ; at i, ingested food substances, x 390. Figs. 16, 17. Encysted plasmodia ; the one at 16 containing numerous in- gested AEthalium spores, x 200. Fig. 18. Young repent plasmodium, with fine, hair-like pseudopodia de- veloped posteriorly, x 390. Fig. 19. A ramifying plasmodium extended on a glass slide ; natural size. Fig. 20. Fragment of the same plasmodium, x 45. Figs. 21-34. Lycogala epidendron, Fries. v if ter De Bary). Fig. 21. Two matured sporangia attached to tan-wood, natural size. Fig. 22. A mature sporangium in perpendicular section, showing disposition of capillitium, x 10. Figs. 23-30. Successive developmental phases from the spore through the flagelliferous stage, until at 29 and 30 the condition of young repent plasmodia is arrived at, x 390. Figs. 31-34. More matured plasmodia, that at 32 exposed to view through making a section of tan-wood, x 390. Fig. 35. Arcyria cinerea , Fries. Figs. 36-45. Arcyria Punicea , Pers. ( after De Bary). Fig. 35. Matured sporangium, x 30. Figs. 36-45. Developmental phases from the germination of the spores through a monadiform condition to the repent plasmodium state ; the example at 45 with i, ingested food particles, x 390. EXPLANATION OF PLATE IV. Figs. 1-14. Didymium Libertianum, De Bary {after De Bary. 2-14, after Cienkoivski). Fig. 1. Matured sporangium in longitudinal section, showing capillitium, x 25. Figs. 2-9. Developmental phases from the germination of the spore to the condition of small repent plasmodia, x 350. Figs. 10 and 11. Small repent plasmodia increasing their dimensions through coalescence with the more minute amoebiform units a a a, x 350. Figs. 12 to 14. More matured plasmodia, that at 12 in the act of engulph- ing a large food corpuscle, i, and that at 13 filled with similarly ingested corpuscles, the attenuatedly extended plasmodium at 14 with four laterally developed contractile vesicles, x 350. Figs. 15 to 22. Similar developmental phases of Didymium ( Physanim ) album ; at 21 the amoeboid units uniting to produce the young plasmodium, fig. 22, x 350. Fig. 23. Spore containing two germs. (After De Bary.) 116 POPULAR SCIENCE REVIEW. Figs. 24-29. Didymium, Fries. ( After Cienkowski.) Fig. 24. Matured sporangium developed in a reticulate form over a living leaf of ground ivy ( Glechoma hederacea), natural size. Fig. 25. Portion of matured erect branching plasmodium. Nat. size. Figs. 26-29. Monadiform and amoeboid germs, that at 28 with i i, ingested food particles, x 550. Figs. 30-55. Physai'um tussilaginis, B. and Br. (From the writer’s original drawings.) Fig. 30. Three matured sporangia adherent to a leaf of common coltsfoot. ( Tussilago farfara), x 5. Fig. 31. Isolated sporangium, x 10. Fig. 32. A small sporangium in lateral view ; towards the extremity a, the spores having escaped, have left bare the thin membranous wall, with its externally scattered calcareous spicula, x 30. Fig. 33. Margin of membranous wall of sporangium, with on the upper surface equidistantly dispersed spicula, and on the under one delicate branching capillitium threads, x 100. Fig. 34. Fragment of sporangial membrane with scattered spicula as seen in superficial view, x 100. Fig. 35. An isolated hexradiate-stellate spiculum from the sporangial mem- brane, x 400. Figs. 36-39. Germinating spores showing different stages of development, x 800. Figs. 40-42. Spores with their walls ruptured, giving exit to amcebiform germs ; at 42 an abnormal example containing two germs, x 800. Figs. 43-48. Successive phases of development of a single extruded germ to a free-swimming monad, as described at page 111, x 800. Figs. 49, 50. Two free-swimming monads, in the former one the vacuoles at if contain exceedingly minute injected carmine particles; the example at 50 with larger, and scattered ingested granules of the same pigment, x 800. Figs. 51, 52. Monads that have entered upon a repent amoebiform existence, the flagella as 3ret being retained ; the example at 52 with ingested carmine particles, x 800. Figs. 53-55. Repent amcebiform zooids, or young plasmodia, representing ulterior developmental phases of the preceding free-swimming monads ; the examples 54-55, with numerous ingested carmine particles, x 800. 117 THE PERMANENCE OF CONTINENTS. By J. STARKIE GARDNER, F.G.S. ‘TT is not too much to say that every spot which is now dry JL land has been sea at some former period, and every part of the space now covered by the deepest ocean has been land.’ This sentence occurs in the latest edition of Ly ell’s Principles of Geology , still perhaps the most authoritative text-book on the subject, and the view it expresses has been generally received as an article of faith by geologists until within a few years, or even months ago. Lately a change of view has taken place, and now many distinguished men hold the completely opposite opinion that oceans have been permanent from the remotest times, and that continents are, and have ever been, fixed lands, subjected to ceaseless modifications of form. Among the most conspicuous partisans of the new theory are Sir Wyville Thomson, Prof. Geikie, and Mr, Wallace; and the latter especially seems to have collected together and presented in his fascinating book, Island Life , every kind of evidence that tends to support it. Nothing appears to have escaped him, yet the whole when summed up must seem to every geologist to fall far short of proof. Still, although the evidence upon which the theory is based is as yet wholly insufficient, it by no means follows that the theory itself is improbable. The chief evidence upon which the Permanence of Continents at present rests, is purely geological. It is argued that the whole of the sedimentary rocks are littoral deposits, or those of inland seas ; and if this can be maintained, the theory would, almost as a matter of course, be accepted. Mr. Wallace, there- fore, endeavours by every means to prove it. Chief among deposits hitherto supposed to be oceanic, is the Chalk ; and to the discussion of this formation, accordingly, almost a whole chapter is devoted. Mr. Wallace expresses the belief that, far from the Chalk sea representing a wide ocean with a 118 POPULAR SCIENCE REVIEW. few scattered islands comparable to some parts of the Pacific, ‘ it formed as truly a portion of the great northern continent as it does now/ The evidence, which he has to set aside, in favour of the Chalk being a truly oceanic deposit, is extremely weighty how- ever, and by no means easily disposed of. Its vast extent — stretching from Sweden to Bordeaux, and from Ireland to China — and its freedom everywhere from impurities derived from the degradation of land, are greatly in favour of its oceanic origin. The areas that are known to have been denuded, and the enor- mous deposits of flint- shingles which characterize the Eocenes from their base upward to the most recent gravels, show how colossal this denudation has been. The Chalk that has escaped seems but the fragment of a mass which once passed under the Atlantic, for even the Scilly Isles are strewn with flint, and the last remains of it in Devon- shire and the north of Ireland are as pure as elsewhere, and show no signs whatever in the Chalk itself, towards its western boundaries, of the proximity of shores. This vast deposit abounds with Globigerina , of species identical with those of the modern Atlantic mud, and with coccoliths and discoliths. Representative siliceous Sponges are abundant in both, and the recent chalk-mud has yielded a large number of the group I* or if era vitrea , which find their nearest representatives among the Ventriculites of the White Chalk. The Echinoderms of the deeper parts of the Atlantic basin are very characteristic, and yield an assemblage of forms which represent in a remarkable degree the corresponding group in the White Chalk. Species of the genus Cidaris are numerous ; some remarkable flexible forms of the Diademidae seem to approach the Echinothuria ;* Rhizoerinus is closely allied to the chalk Bourgueticrinus, while even among fish the genus Beryx, so abundant in the Chalk, has been found by Dr. Carpenter, and the fresh light that the pub- lication of the deep-sea fish of the Challenger Expedition is likely to throw on the subject will be looked forward to with much interest. Prof. D uncan, t when investigating Corals, became impressed with the remarkable persistence of character and absence of variability in those of the deep-sea fauna. ‘ The dredging in 1095 fathoms off the coast of Portugal, which yielded Renta - crinus JVyvillc-Thomsoni, Jeffreys, produced many corals; and the series presented an eminently Cretaceous facies. The genus Bathycyathus, whose species, Sowerbyi} is so well known in the Upper Greensand, was represented there by numerous specimens of a species closely allied to that form/ * Sir Wyville Thomson, Nature , vol. iii. p. 297. t Quart. Jour. Geol. Soc. xxvii. p. 437. THE PERMANENCE OF CONTINENTS. 119 A new species of C ary ophy Ilia, allied by its structural pecu- liarities to C. Bowerbanki of the Gault, and a species identical witb tbe well-known Cary ophy Ilia cylindracea, Reuss, sp., were discovered at the same time. The homotaxis of part of the Coral fauna of the Atlantic and that of the Cretaceous ocean, Prof. Duncan considers to be very remarkable. Against this well-nigh irresistible evidence in favour of the oceanic origin of Chalk, Mr. Wallace states that no specimen of Globigerina ooze yet examined agrees, even approximately, with Chalk in chemical composition. The differences between the few analyses that have been published, are chiefly in the relative quantities of carbonate of lime, silica, alumina, and oxide of iron. It is by no means apparent that Sir W. Thomson’s sample is the nearest analogous deposit to Chalk that could be found in the beds of the Atlantic or Pacific ; but supposing it to be so, the great changes in chemical composition to which Chalk has been subjected since its consolidation, are entirely overlooked in comparing the analyses.* Chalk is, and probably always has been since its upheaval, constantly saturated with percolating rain-water, which enters as soft water charged with carbonic acid, and comes out in springs of hard water charged with car- bonate of lime ; and this alone in the course of ages would carry away the more soluble constituents such as iron, alumina, and magnesia. An even more important change is due to the removal by segregation of its silica into the form of flint. This, doubtless, took place when the silica was in a colloid state, and seems to have been arrested, whilst the Chalk was consolidating, wherever harder and softer layers alternate. Its once viscid, almost fluid, state is shown by the manner in which it has pene- trated the minutest pores of Echinoderms before destroying the shell ; and it seems probable from the way in which it has re- placed carbonate of lime, "I* that it had not parted with its * The analyses relied upon in support of this are by Sir W. Thomson, of Globigerina ooze, viz. : — Carbonate of Lime Carbonate of Magnesia . Alumina and Oxide of Iron Silica Supposed Volcanic Dust And of Chalk, by David Forbes Carbonate of Lime Carbonate of Magnesia Alumina and Phosphoric Acid Chloride of Sodium . Insoluble debris 43*93 to 79-17 per cent. 1-40 to 2-58 6-00 P to 32-98 „ 4*60 to 11-33 „ 4-60 to 8-33 „ Grey Chalk, White Chalk, Folkestone. Shoreham. 94-09 98-40 0-31 0-08 a trace 0-42 1-29 — 3-61 1-10 t All the carbonate-of-lime shells are replaced in the Blackdown deposits by silica. 120 POPULAR SCIENCE REVIEW. organic acids. That it did not assume the solid state until at least after the partial consolidation of the Chalk is obvious, through the filling in of fissures at right angles to the bedding, which could not have existed when it formed the surface sedi- ment of the ocean bottom. In comparing the White Chalk analysis with that of the ooze, therefore, we must hear in mind that, as already pointed out by Mr. Sorby, Mr. Sollas, and Dr. Wallich, a portion of flint must be added equal to that which has been separated away. In a similar manner, iron has been removed and segregated together, to be crystallized principally into globular balls with a radiating structure.* The shells composed of carbonate of lime, such as those of Gastropods,-)- Cephalopods, and Dimyaria, seem also to have been dissolved away, perhaps by the rain-water which falls upon the Chalk, saturates it, and passes through it by capillary action unceasingly- Another evidence of change is shown in the crys- talline condition of shells composed of phosphate of lime, such as the Aviculidse, the Branchiopoda, the Echinodermata, &c. It is surprising to find that no allusion whatever is made to this range of facts by Mr. Wallace ; and those of his readers who are unacquainted with them, are left unaware that Chalk has undergone such great changes in its composition since it was the bed of the sea, as to deprive the unqualified statement that the analyses of Chalk and Globigerina ooze ‘ do not even approxi- mately agree/ of any scientific value. These facts further tend to show, as indeed is obvious from a comparison of the faunas, that the similarity in the analysis of the Oahu chalk and the White Chalk, upon which so much stress is laid, is purely superficial.! In spite of the fact * It aBsumes very beautiful forms in the Grey Chalk, and has occasionally completely replaced Sponges. The iron is frequently ochreous in theWhite Chalk. t Gastropods are found as casts in the Grey Chalk, slightly coated with iron, and occasionally traces are met in the Lower White Chalk in the same condition. Higher than this even the most indistinct outlines of the larger forms, such as Fleur otomaria, are rare. I have seen but one trace of shell on any spiral Gastropod, and this on a fragment of Funis from the White Chalk near Norwich. Small thin fragments adhered to the cast, and the circumstance is remarkable as Funis almost alone of the Gastropods pre- serves its shell in the Cambridge Greensand. The shells of Cephalopods seem to possess a slightly greater resisting power, and their casts are, as a rule, more distinct. f Analysis of Oahu chalk : — Carbonate of Lime . 92-800 Carbonate of Magnesia . 2-385 Alumina .... 0-250 Oxide of Iron .... 0-543 Silica 0-750 Phosphoric Acid and Fluorine 2113 Water and loss 1-148 Geology of the U. S. Exploring Expedition , p. 150. THE PERMANENCE OF CONTINENTS. 121 that ‘this chalk consists simply of comminuted corals and shells of the reef,’ and is, when examined microscopically, ‘ found to be destitute of the minute organisms abounding in the chalk of England/ Mr. Wallace states that in several growing reefs a similar formation of modern chalk, undistinguishable from the ancient, has been observed. Mr. Wallace thus assumes that the Chalk is derived from excessively fine mud produced by the decomposition and denu- dation of coral reefs ; but this view appears to me to be untenable. Mr. Murray expressly states that no Globig evince were found in any of the enclosed seas of the Pacific which possess this chalky bottom ; and to account for Globigerina in the Chalk it has to be supposed that the Chalk sea was open to the Gulf Stream, i.e. the Atlantic. Further, to provide the necessary conditions we are obliged to suppose this vast sea to have been bordered with islands and coral reefs, and that no large rivers flowed into it, and yet absolutely no traces of these coral reefs remain, while an inland sea could hardly have existed in proximity to a great permanent continent without some rivers draining into it. A curious piece of reasoning is that in the Maestricht and Faxoe chalks ‘ we have a clear indi- cation of the source whence the white calcareous mud was derived which forms the basis of the chalk/ If these local and far newer deposits are seen to be highly coralline and the Chalk is not seen to be so, we have rather a clear indication that they were not deposited under the same conditions. The presence of Mosasaums in the Maestricht beds, and the far newer aspect of its fauna, show that it must have belonged to an altogether different period, probably the one represented in America by a great so-called Cretaceous series containing a mixture of Cretaceous and Tertiary mollusca, dicotyledonous plants, and Mosasaurus. From every point of view, in fact, the inference that the vast Cretaceous deposits are analogous to small local deposits of coral mud in the Pacific does not appear to be the true one. With regard to the probable depth of the ocean which deposited the Chalk, the evidence brought together by Mr. Wallace is less unsatisfactory. Mr. J. Murray, for instance, sees the greatest resemblance to it in mud from depths of less than 1000 fathoms ; and Dr. Gwyn Jeffreys finds that all the Mollusca of the Chalk are comparatively shallow- water forms. We must bear in mind, however, that the characteristically deep-sea families and genera, such as Bulla and the Solenocon- chia, Leda, JSfeoera, and Verticordia, would have long since been dissolved away if present ; while great and highly characteristic cretaceous genera, such as Inoceramus and HippuriteSy are wholly 122 POPULAR SCIENCE REVIEW. extinct, and nothing therefore can be safely predicated con- cerning their habits. In the Grey Chalk near Folkestone dark impressions of nearly all the deep-sea Mollusca enumerated above are abundant ; and the Gault and a part of the Lower Greensand are full of their shells in perfect preservation. Their absence in England at least, from the Chalk, seems very clearly due rather to subse- quent destruction than to their never having been present. Of the Chalk genera that are preserved, Pecten , Amussium, Lima , Spondy- i lus, Anomia , and the Brachiopoda are represented by Dr. Gwyn j J effreys as having been dredged at from 1450 to 1750 fathoms and j upwards. As for the abundance of Ammonites showing, as Dr. S. P. Woodward once supposed, the water to have been as shallow as thirty fathoms, Mr. Wallace himself would be the first to repudiate such mere supposition, were it urged against the theory he seeks to establish. Were Nautilus and Spirula i shallow- water forms they would long since have been captured abundantly. The still existing shells of the Chalk itself are so few that little weight can be attached to them as an indication of depth, but in the lower Cretaceous deposits Mollusca abound, as already stated, and in perfect preservation ; and their facies, taken with the complete absence of shallow-water forms, implies, Dr. Gwyn Jeffreys believes, a depth of sea in the Gault period of somewhere about 1000 fathoms. Mr. Sorby, from quite other considerations, believed the Gault to be an altered red clay, similar in all essential respects to the red clay j now forming at the ocean-bottom. There seems thus to be abun- dant evidence, endorsed by our greatest authorities, that at least some of the Cretaceous deposits were deep-sea, while there is a total absence in them of anything necessarily indicating the proximity of land.* With regard to the Chalk itself, however, the facts are still somewhat contradictory, for it far overlaps the Gault and Grey Chalk in Devonshire, and rests upon green- sand ; yet although it thins out to the west it remains a per- fectly pure rock, without any apparent evidence of the upper part of the formation having gradually shallowed as the sea-bed became upheaved. The immensity of the gap, seldom adequately realized, between the true Cretaceous and the next overlying beds, implies an interval sufficient to have permitted the grandest changes in the distribution of land and water, and the gulf of the Atlantic, which stretched over the greater part of Europe, * No American or European so-called Cretaceous land-flora can be proved to be as old as our White Chalk. The few vegetable remains found in marine Cretaceous rocks are not incompatible with the deposits having taken place at a distance from shore. THE PERMANENCE OF CONTINENTS. 123 to become elevated; and, after enormous denudation, to be converted into land. But even altogether apart from what is to be learned from the Cretaceous rocks, it is not apparent that continents have been uninterruptedly permanent. Australia and Asia, Africa and Madagascar, New Zealand and Australia, Europe and America, are all supposed to have been united at some more or less remote period ; and to explain the present distribution of organisms, seas of a thousand fathoms depth are bridged over as often as it happens to be deemed requisite. But it is still questionable whether these former land connexions, which are admitted by Mr. Wallace, will be found sufficient to explain all the past as well as present peculiarities of distribution. For instance, a much more southerly land connexion between Eng- land and America seems required to explain the presence of tropical American plants, such as palms, in our Eocene, because their absence in beds of corresponding age in the United States and Greenland implies that they did not pass along the northern route traced out for them. If sea-beds have been elevated to the extent of a thousand fathoms, and if there are forces capable of elevating the highest mountains in the world from below the sea level within a comparatively recent period, why are 4 hypo- thetical continents bridging over the deep oceans ’ ‘ so utterly gratuitous and entirely opposed to all the evidences at our com- mand/ as Mr. Wallace wishes us to believe ? There appears to be no valid reason why Europe should not have been con- nected with South America, by the so-called Atlantic ridge, or even Australia with South America by way of Easter, Gambier, and the Fiji Isles ; for if these great banks, with islands occa- sionally rising to the surface, do not mean changes of level in the sea bottom, whether of elevation or depression, what do they mean P To take other instances, in which Mr. Wallace’s explanations do not seem to be the best solution of the facts. Sir Joseph Hooker, in his singularly interesting introductory essay to the New Zealand flora, stated that seventy-seven plants are common to New Zealand, Tasmania, and South America, comparatively few of which are universally distributed species. Further, there are upwards of 100 genera or well-marked groups of plants almost confined to lands of the south temperate zone, effecting ‘ a botanical relationship or affinity between them all, which every botanist appreciates/ For reasons which appear to be unanswerable, he has rejected the theory that these plants were transported across the seas which now separate these lands, | and considers that the plants of the Southern Ocean are ‘ the remains of a flora that had once spread over a larger and more continuous tract of land than now exists in that ocean/ and that 124 POPULAR SCIENCE REVIEW. this land had been broken up by climatic and geological causes. Mr. Wallace supposes an emigration to have taken place from Chili by way of the South Shetland Isles, 500 miles south of Cape Horn, thence by way of an antarctic continent or group of isles, which probably extend around the South Polar area to Yictoria Land, again on to the outlying Young Island, across 750 miles of sea to Macquarie Island, and, finally, across another similar distance to the 1000 fathom line, which, he con- siders, 4 probably marks the former southern extension of Tasmania/ This appears a route beset with obstacles both climatal and geographical, and broken up by extents of sea, which Sir Joseph Hooker has expressly stated many of the plants com- mon to these remote lands to be specially unfitted to traverse.* The bed of the ocean is as undulating as the surface of the land ; and this is hardly the condition it would have as- sumed had its state been that of eternal rest. The objection that oceanic islands, with the exception of Hew Zealand and the Seychelles, hardly ever afford traces of Palaeozoic or Secondary formations, and cannot therefore be remains of continents, is far from insuperable. The smaller oceanic islands, to which the statement alone seems to apply, would, j if belonging to continental areas, be only the summits of mountains that are either rising or sinking; and as they are mostly of comparatively recent volcanic origin, it is hardly likely that we should meet with Palaeozoic or Mesozoic stratified rocks exposed on them. It is even more curious, if they have been uplifted from the great depths which surround them, that no traces of the bottom sediment, which must have been accumu- lating continuously from the Palaeozoic period, should have been brought up with them. Speculation is, however, useless, for the only geological fact regarding them about which we can be certain is that whatever secrets they have to dis- I close lie buried deeply under volcanic outbursts. It is certainly strange that Mr. Wallace makes no difficulties whatever in admitting changes of level in the sea bottom j to the extent of 1000 fathoms, but will not entertain the j possibility of any greater upheaval. Yet some oceanic islands must have been upheaved from vastly greater depths, and mountain chains have been raised to three times that ex- tent in comparatively recent times. It is well known that these forces are unceasingly acting, yet no reason is put forward to show why an elevating force once set in action in the centre of an ocean, should not continue gradually to act until even a continent is formed. In the * The elevation of from 400 to 1800 feet which Chili and Patagonia have undergone for several hundred miles since the existence of the living species of Mollusca must imply at least correspondingly great subsidence elsewhere. THE PERMANENCE OF CONTINENTS. 125 words of Prof. Huxley, ‘ Surely there is evidence enough and to spare that the Cretaceous sea, inhabited by various forms, some of whose descendants Sir W. Thomson, as I believe justly, recognizes in the present deep-sea fauna, once extended from Britain over the greater part of central and southern Europe, North Africa and Western Asia to the Himalayas. In what possible sense can the change of level which has made dry land of, and sometimes mountain masses of, nine-tenths of this vast area, he said, to be “ in direct relation to the present ex- isting coast-lines.” That the abyssal plains were ever all elevated at once is certainly so improbable that it may justly he termed inconceivable ; hut there is nothing, so far as I am aware, in the biological or geological evidence at present acces- sible to render untenable the hypothesis that an area of the mid- Atlantic, or of the Pacific sea-bed, as big as Europe, should have been upheaved as high as Mont Blanc, and have subsided again any time since the Palaeozoic epoch, if there were any grounds for entertaining it.’* It is so obvious that the causes which lead to elevation and subsidence must react one upon the other, that I am tempted to speculate upon them and their effects on deep-sea basins. I have long been struck with the almost universal tendency to depression exhibited in areas occupied by deltas and estuaries. The thought has occurred to many, and has perhaps been most clearly expressed by Dr. Charles Picketts, that this subsidence is produced by the accumulation of sediment, f The cause appears insignificant, yet something must determine the move- ment of the Earth’s crust, and even an accumulation of a few feet of clay over several square miles may create disturbance, and eventually lead to a downward tendency. Supposing a sediment, 50 feet in depth and entirely submerged, to have displaced an equivalent of sea-water, we should have an in- creased pressure per square yard, taking the mean density of the materials composing a delta at 120 lbs. per cubic foot, of I rather more than 25,000 lbs., or about 34,848,000 tons per square mile. As soon as the whole of the sea- water on an area is displaced and movement has set in, every cubic yard of sediment deposited adds a weight of about 3240 lbs. ; and when we see that deltas have accumulated to depths of perhaps even beyond 1000 feet, and extend, as in the Mississippi, to 19,450+ square miles, we can realize how vast a force is present. ? * Review of the first volume of the publications of the Challenger. A at lire, vol. xxiii. p. 1. t Geol. Mag. 1872, vol. ix. p. 119. I X Report, on Mississippi U. 8. War Department , 1864, p. 434. Records of borings in deltas are, the Po, 500 feet, Ganges, 481 , Mis- 126 POPULAR SCIENCE REVIEW. The inference as to the origin of depression, which can he drawn from delta and estuary areas, may equally be applied to coral-reefs and islands, and even to great accumulations of ice, as in Greenland ; for in almost all such situations there appears to he a nearly continuous downward tendency. There are even grounds for supposing that the depression generally ob- servable round sea-coasts may he due to a similar cause. The sediments from the wasting of the shore* are known to he thrown down almost wholly upon a belt thirty miles wide. The moving power of waves is not felt to a greater depth than forty feet ; and it is therefore difficult to explain, except upon the the theory of subsidence, why in the absence of currents, the sea in proximity to shore should ever he more than forty feet deep. All ancient lands should he surrounded by extensive shoals of uniform depth, for tides appear to have no permanent action in removing sediment, and shore-currents of the requisite power are local. The prevailing action, indeed, on our own coasts appears to he silting, if we may judge from the way wrecks become imbedded ; and the evidences of sub- sidence are innumerable. The records of submerged land vegetation are frequent, and though, on the other hand, there are in many places raised beaches, it should he remembered that while these are always conspicuous, depressed beaches can- not easily attract notice. If it were once conceded that sedimentation directly caused subsidence, we should discover a reason for the permanence of ocean basins, for deposition must have been unceasing since Palaeozoic times, and would to a large extent have filled in the depths of the ocean were this action not compensated by con- stant and gradual depression, exceeding perhaps the rate of sedimentation. The mean of four experiments made on the Challenger expedition, determined the quantity of carbonate of lime in the form of living organisms in the surface waters to be 2*545 grammes, so that if these animals were equally abundant in all depths down to 100 fathoms, it would give 16 tons of carbonate of lime to each square mile of 100 fathoms depth, f The weight of sediment must exercise enormous pressure, tending to make the greatest depths of the sea permanent, and to continually elevate lines of least resistance into ridges or banks, leading where the state of tension is extreme, to sisdppi, 6.30, in which the lowest beds reached were turf and vegetable matter. The total thickness of many deltas, such as that of the Ganges, may be inferred from the depth of the sea in which they are accumulating. * The denudation has been estimated to equal nineteen feet in 1000 years. t In great depths shells are reduced to bicarbonate, and this may imply loss of material. The supply of lime does not seem, however, to be obtained to any great extent from dead organisms, but is probably kept up by rivers. THE PERMANENCE OF CONTINENTS. 127 isolated volcanic outbursts. The lines of absolute least resist- ance would probably, however, generally coincide with sea- margins, and upon coasts, therefore, while we might find a tendency to local depression, owing to the littoral sedimentation at a few miles from land, there would be inland a far more important and preponderating tendency to elevation. Thus there would ever be a direct action deepening ocean basins where they are deepest, and raising up the shallower parts to higher levels, thereby slowly lessening the superficial area occupied by seas. On the other hand, the dry land would extend in a corresponding degree, and its surface become more diversified, for new mountain chains would in succeeding ages have a tendency to greater and greater elevation. I think all we are able to gather from the records of Palaeozoic rocks points to a comparative uniformity in the condition of the earth’s surface in remote times, there being neither evidence of great depths in the sea, nor of mountainous elevations in the land. These conditions, to judge from palae- ontological evidence, were increasingly modified during the Secondary period, and on to the present day ; so that the theory that increasing weight causes increased depth, derives sup- port from the G-eological Record. PRELIMINARY NOTE ON THE EXISTENCE OF ICE AND OTHER BODIES IN THE SOLID STATE AT TEMPERATURES FAR ABOVE THEIR ORDINARY MELTINGr POINTS. By THOMAS CARNELLEY, B.Se., Professor of Chemistry in Firth College, Sheffield.* IN the present communication I have the honour to lay before the Royal Society a detailed description of experiments, proving that under certain conditions it is possible for ice and other bodies to exist in the solid state at temperatures far above their ordinary melting points. On a future occasion I hope to submit to the Society a full account of the investigation of which these experiments form a part, together with the conclu- sions to be drawn therefrom. The bodies whose behaviour I propose to discuss at present are ice and mercuric chloride. Ice. In the case of ice the great difficulty to he overcome is to maintain the pressure in the containing vessel below 4* 6 millims., i. e ., the tension of aqueous vapour at the freezing point, for it will be easily understood that if the ice be but slightly heated the quantity of vapour given off would soon he sufficient to raise the pressure above that point. After several fruitless attempts the following plan, involving the principle of the cryophorus, was adopted. A strong glass bottle, such as is used for freezing water by means of Carre’s pump, was fitted with a cork and glass tube C (fig. 1), and the cork well fastened down by copper wire and paraffin wax. A and C were then filled with mercury, and C connected with the end of the tube DE by means of the piece of stout india-rubber pump tubing B, a thermometer having been previously attached by the wire x to the lip of the tube * From the Proceedings of the Royal Society, 1881, No. 209. EXISTENCE OF ICE AT HIGH TEMPERATURES. 129 at B. The connexion at B was made tight by fine copper wire. The tube DE was about one inch in diameter, and about four feet long from the bend to the end E ; after connexion with C it was completely filled with mercury, care being taken to expel the air from A, C, and DE as completely as possible ; the whole was then inverted over the mercurial trough E, as Fig. 1.* shown in the figure, when the mercury fell to o, the ordinary height of the barometer. The mercury was run out of A by tilting up the bottle and inclining the tube DE. By this means a Torricellian vacuum was obtained from A to o. DE was next brought to the vertical, and the bottle A placed in the trough P. A tin bottle Gr without a bottom was fitted with a cork, so that it might slide somewhat stiffly along DE. * For the use of this and the following figures we are indebted to the kindness of the President of the Royal Society. NEW SERIES, VOL. V. NO. XVIII. K 130 POPULAR SCIENCE REVIEW. To begin with, the tin bottle was placed in the position G and filled with a freezing mixture of salt and ice. Some boiled water was then passed up the tube DE, sufficient to form a column at M about two inches deep. The thermometer H had been previously arranged, so that its bulb might be one or two inches above the surface of the water M. The bottle A was next surrounded by a good quantity of a freezing mixture of salt and ice, in order that any vapour given off from the water at M might be condensed in A as fast as it was formed, and thus the internal pressure might never be more than about TO to 1*5 millims. When A had been sufficiently cooled, which required about fifteen minutes, the tin vessel G was slid down the tube DE, and its freezing mixture removed. The water at M had then solidified to a mass of ice, which on heating with the flame of a Bunsen’s burner melted either wholly or partially, and the liquid formed began at once to boil. The fusion com- menced first at the bottom of the column of ice, whereas the upper part fused only with difficulty, and required rather a strong heat. The fusion in this case was probably due to the steam evolved from the lower portions of the ice column being imprisoned and unable to escape, and hence producing pressure sufficient to cause fusion. When the greater part of the ice had been melted the tube was tightly clasped by the hand, the heat of which was suffi- cient to produce a somewhat violent ebullition. The liquid in boiling splashed up the side of the tube and on to the bulb of the thermometer, where it froze into a solid mass, as repre- sented in fig 2. By this means the ice was obtained in mode- rately thin layers. The tube at the points indicated by the arrows was then strongly heated by the flame of a Bunsen’s burner, with the following results : — The ice attached to the sides of the tube at first slightly fused, because the steam evolved from the surface of the ice- next the glass being imprisoned between the latter and the overlying strata of ice, could not escape, and hence produced pressure sufficient to cause fusion, but as soon as a vent-hole had been made fusion ceased, and the whole remained in a solid state, and neither the ice on the sides of the tube nor that on the bulb of the thermometer could be melted, however great the heat applied, the ice merely volatilizing without previous melting. The thermometer rose to temperatures vary- ing between 120° and 180° in different experiments, when the ice had either wholly volatilized or had become detached from the bulb of the thermometer. The ice attached to the latter did not partially fuse at the commencement of the heating, because, the heat reaching the outer surface of the ice first, evaporation could take place from a free surface, and the vapour EXISTENCE OF ICE AT HIGH TEMPERATURES. 131 not become imprisoned, as was tbe case with the ice attached to the sides of the tube. These experiments were repeated many times, and always with the same result, except in one case in which the heat applied had been very strong indeed, and the ice attached to the sides of the tube fused completely. On removing the lamp, however, for a few seconds the water froze again, not- withstanding that the portion of the glass in contact with it was so hot that it could not be touched without burning the hand. Fig. 2. The chief conditions necessary for success appear to be — - (1) That the condenser (A, fig. 1) is sufficiently large to main- tain a good vacuum. In the present case the capacity was about three quarters of a litre ; (2) That the ice is not in too great mass, but arranged in thin layers. Further, in the case where the heat is applied to the under surface of the layers of ice, the latter must be sufficiently thin to allow of a vent-hole being formed for the escape of the steam coming from below, 132 POPULAR SCIENCE REVIEW. otherwise fusion occurs. When the heat is applied to the free surface of the ice, the layers may be much thicker. Mercuric Chloride, m. p. = 288° C., re-solidifies at 270-275°, b. p. = 803°. About 40 grs. of pure mercuric chloride were placed in the tube (A, fig. 3), and a thermometer arranged with its bulb imbedded in the salt. The drawn-out end of the tube was con- nected by stout india-rubber tubing with one branch of’ the three-wayed tube B, whilst the other was attached to the mano- meter C. B was connected with a Sprengel pump, fitted -with an arrangement for regulating the pressure. When the pressure had been reduced by means of the pump to below 420 minims., the mercuric chloride was strongly heated by the flame of a Bunsen’s burner, with the following results : — Not the slightest fusion occurred, but the salt rapidly sub- limed into the cooler parts of the tube, whilst the unvolatilized portion of the salt shrank away from the sides of the tube and clung tenaciously in the form of a solid mass to the bulb of the thermometer, which rose considerably above 300° C., the mercury of the thermometer shooting up to . the top of the stem. After slight cooling the air was let in, and under the increased pressure thus produced the salt attached to the bulb of the thermometer at once melted and began to boil, cracking the tube at the same time. The experiment was next varied as follows About the same quantity of chloride was placed in the tube A, fig. 3, as before, and heated by the full flame of a Bunsen’s burner. The lamp was applied during the whole of this experiment, and the size of the flame kept constant throughout. The mercuric chloride first liquefied and then boiled at 303° under ordinary pressure, and whilst the salt was still boiling the pressure was gradually reduced to 420 millims., when the boiling point slowly fell to 275°, at which point the mercuric chloride suddenly began to solidify, and at 270° was completely solid, the pressure then being 376 millims. When solidification was complete the pump was stopped working, but the heat still continued to the same extent as before. The salt then rose rapidly to temperatures above that at wrhich a thermo- meter could be used, but not the least sign of fusion was observed. From the completion of the solidification to the end of the experiment the pressure remained at about 350 millims. The above experiment, which was repeated three times, EXISTENCE OF ICE AT HIGH TEMPERATURES. 133 shows, therefore, that when the pressure is gradually reduced from the ordinary pressure of the atmosphere to 420 millims., and the boiling point simultaneously from 303° to 275°, the salt solidifies while it is still boiling and in contact with its own hot liquid, notwithstanding that it is being strongly heated at the same time ; and that, after solidification is complete at 270°, the temperature then rises far above the ordinary boiling point (303°) of the substance without producing any signs of fusion. Fig. 3. Under ordinary circumstances, mercuric chloride melts at 288° and re-solidifies at 270 — 275, i. e., at a temperature identical with that at which it solidifies under diminished pressure, as above described. The solid mercuric chloride obtained on solidification under the combined influence of diminished pressure, and the applica- tion of a strong heat had a peculiar appearance, quite different 134 POPULAR SCIENCE REVIEW. from that produced when the substance is allowed to solidify in the ordinary way. It appeared to consist of a mass of pearly leaflets closely packed together round the bulb of the ther- mometer. Any final explanation of these phenomena is reserved until further experiments have been made. Since writing the foregoing, it has been said in explanation of the phenomena therein described, that the thermometer, though imbedded in the mass of the ice, did not really indicate the true temperature of the latter. With the object, therefore, of proving whether the ice is hot or not, I have, at the suggestion of Professor Eoscoe, made the following calorimetrical deter- mination : — The arrangement of the apparatus was so modified, that the ice, after being strongly heated, could be suddenly dropped into a calorimeter containing a known quantity of water of known temperature. The resulting temperature, after the ice had been dropped in, was read off by a thermometer graduated so as to indicate a difference of 0o,05 C. The weight of the ice was found by re- weighing the calorimeter. So far, I have only had the opportunity of completing the two following determinations, and in the second of these the weight of the ice could not be found, as a small quantity of water was lost out of the calorimeter, owing to a sudden jerk at the moment the ice entered it : — (1.) Weight of water in calorimeter, including the value of the latter = 185 gnus. Weight of ice dropped in = 1*3 grins. Temperature of calorimeter before . . = 13'4 „ „ after . . = 13*6 Rise in temperature = 0*2 M (0-0 + 80 W = W (T — 0) (185 x 0-2) + (80 x 1-3) = 1*3 (T - 13*6) T = 122° C. Where T = temperature of ice. (2.) Weight of water in calorimeter, &c. — 185 grms. Temperature of calorimeter before . . = 12*7 v ,, after . . = 12*8 Rise in temperature = 0T On weighing the calorimeter after the experiment, the increase in weight was only 0*15 grms., but as a portion of the EXISTENCE OF ICE AT HIGH TEMPERATURES. 135 water had been jerked out during the operation, the true weight of the ice, and therefore its temperature, could not he found. But since the calorimeter had slightly risen in temperature, the ice must have been above 80° C. From the nature of the experiment, as carried out on the present scale, the weight of the ice which can be dropped into the calorimeter is only small, and therefore the rise in tem- perature is but slight. But since a fall in temperature of a much larger amount ought to have been obtained had the ice been at 0°, it is considered that the above experiments are con- clusive. Great care was taken, in order to obtain correct temperatures in the calorimeter. The latter was enclosed in several casings, and the water was allowed to stand in it for several hours before the experiment, so that it might first attain the temperature of the room, whilst the time which elapsed between the readings of the thermometer before and after the ice was dropped in would not be more than from 10 •to 15 seconds. In the course of the next few weeks I intend to make one or «two more determinations, and, if possible, on a larger scale. 136 ON THE FORMER EXISTENCE OF THE: ROE-DEER IN ENGLAND. By J. E. HARTING, F.L.S., F.Z.S. IT is always a pleasing exercise of the understanding to> investigate the causes which produce important changes in animated nature ; and this is especially the case when those changes have relation to our own country, and to animals which,, once common here, have from one cause or another become- extinct. Our old English foresters were wont to distinguish three classes of game, namely, Beasts of Yenery (or of the forest),, as the Hart and Hind, Boar and Wolf ; Beasts of Chase, as the Buck and Doe, Fox, Marten, and Roe ; and Beasts and Fowls of Warren, namely, the Hare, Coney, Pheasant, and Partridge. When Turbervile, three centuries ago, wrote his Book of Hunting , and woodcraft in all its branches was accounted an essential part of a gentleman’s education, the Roe- deer held an important place amongst the ‘beasts of chase.’ During its first year it was termed a kid , the second year a gyrle , the third year a liemule , the fourth year a Roebuck of the first heady and the fifth year a fair Roebuck . When several were seen together they were spoken of as a bevy of Roes ; and the season for hunting them was between Easter and Michaelmas for bucks, and between Michaelmas and Candlemas for does.. While a hart was ‘harboured’ and a buck ‘lodged’ in the fern or underwood, a roe was said to be ‘bedded.’ The voices of all three were distinguished, and it was said the Red-deer ‘ belleth,’ the Fallow-buck ‘ groaneth,’ and the Roe-deer ‘belloweth.’ The first named was tracked by his ‘slot,’ the second by his ‘ view,’ the last by his ‘ foil ; ’ and, in the ancient jargon of the chase, various were the terms applied to each when hunted. It is not a little curious that of the three species of deer FORMER EXISTENCE OF THE ROE-DEER IN ENGLAND. 137 which, were once plentiful in England, the smallest should be the first to become extinct. One would have supposed that its diminutive size, its timid disposition, and retiring habits, combined with fewer require- ments as regards food, would have enabled it to linger on and hold its own in the remnants of our ancient forests, and even in smaller coverts where its allies, the Red- deer and the Fallow- deer, from their conspicuously larger size could not hope to escape detection. This might have been so had it not been for the important circumstance that both the Red-deer and Fallow- deer were at an early period taken directly under man’s pro- tection by being enclosed in parks on the first distribution of forest lands. The Roe-deer not only disdained such protection, no ordinary park-paling being high enough to keep it within bounds, but its wandering disposition necessitating a great tract of country to roam over, rendered it unable to brook the confinement to which the larger animals soon became accustomed. Under these cir- cumstances other causes soon supervened to bring about its extinction. Deprived of the protection afforded to other deer, the destruction of its native woods and the gradual cultivation of moors and waste lands placed it more than ever at the mercy of its enemies. It would be easily approached and killed, its size rendering it a good mark; and on the other hand its slow rate of increase (bringing forth but once a-year, and having usually but two fawns at a birth), would be insufficient to counteract the destruction to which it became continually exposed. That the Roe-deer must at one time have been plentiful in England, and very generally dispersed throughout the country, is made apparent in a variety of ways. To turn, first, to the geological evidence. Its remains have been discovered in such widely distant and dissimilar situations as in the barrows and bone-caves of Derbyshire,* in the peat of Berkshire and Hants, f in the deposits of the Thames Talley, £ in the lower marl of the Yale of Kennet,§ and in the caverns of Devonshire.!! That it was at one time a native of the eastern counties of England may be inferred from the discovery of its horns and bones mingled with those of the Red-deer and other animals, now extinct, in the soil of an ancient submerged forest * Pennington, Notes on the Burrows and Bone-caves of Derbyshire, 1877. t Collet, Phil. Trans. 1757, p. 109; Pennant, Brit. Zool. yoI. i. p. 60. t Boyd Dawkins, Pop. Sci. Be v. Jan. 1868 ; Woodward, Geol. Mag. Sept. 1869, and Walker, Trans. Essex Nat. Field Club , p. 38. § Sussex Archceol. Coll. xxiv. p. 160. || Bellamy, Nat. Hist. South Devon , p. 440 ; Brit. Assoc. Report , 1869,. p. 208. 138 POPULAR SCIENCE REVIEW. which has been found to extend for more than forty miles along the coasts of Norfolk, and which during the prevalence of very low tides is traceable here and there by the numerous stumps of trees which may be seen still standing erect with their roots attached to them, and penetrating in all directions into the loam or ancient vegetable soil on which they grew.* ‘ The horns of the Roebuck/ says the Rev. Richard Lub- book,*)* ‘ are much less frequent in occurrence here than those of the Stag ; but a good pair, with part of the skull annexed, were dug up by the turf-cutters on Buckenham Fen, near Attleburgh, and they have occasionally occurred in other situations/ If we dip into the records of bygone days we shall find that the Roebuck is very anciently mentioned as a beast of chase. The British name for it was Iwrch. In the Colloquy of Alfric it is included amongst the different kinds of game which the Saxon hunter usually pursued. ‘ I take harts, boars, and deer/ he says, ‘ and roes, and sometimes hares/ When asked how he practises his craft he replies, ‘ I braid nets and set them in a convenient place, and set on my hounds that they may pursue the beasts of chase, until they come unexpectedly to the nets, and so become entangled in them, and I slay them in the nets/ The practice of taking Roe- deer in nets is referred to in Domesday as being in vogue in Lancashire at the date of the Conquest. Thus, ‘ Roger ins de Lad ten Cortune. Ibi est haia capreolis capiend / The haia, haye, or haie, as it is variously spelled, properly signified the hedge or fence enclosing a forest or park, but by an easy metonymy the word was transferred from the enclosing fence to the area enclosed by it.J In the case of the Roe- deer it doubtless implied an enclosed area into which the animals were driven, and having outlets here and there across which nets were hung for their entanglement and capture. The existence of such ‘ haies ’ may be found noticed in ancient grants of land during many subsequent centuries. § Under the Welsh laws of Howel Dha, a.d. 940 (cap. xix.), the skin of a Roebuck was worth a penny, of a Hart eight- pence, of a Hind sevenpence.|| The Welsh name for the Roe was Iyrchod. At the time of the Conquest, Roe-deer were to be found * Lyell, Antiquity of Man. f Lubbock, Fauna of Norfolk. X For a full and interesting explanation of this word see Whitaker, His- tory of Whalley, vol. i. p. 283. § See Blount’s Ancient Tenures. || An English translation of these laws will be found appended to The Myvyrian Archceoloyy of Wales, collected out of Ancient Manuscripts, ed. Owen Jones and others. (Denbigh, 1870.) Vide p. 1056. FORMER EXISTENCE OF THE ROE-DEER IN ENGLAND. 139 in the isle of Efy. From an account of the natural pro- ductions of this island, drawn up for the information of the Conqueror, and embodied in what is now known as the ‘ Liber JEliensiSy it appears that Ely at that date was remarkably fertile in its resources, not only affording pasturage to number- less flocks and herds, but yielding plenty of fish and wild fowl, as well as harts and hinds, roes and hares, which abounded in its woods.* William the Conqueror punished with the loss of eyes any who were convicted of killing a wild boar, stag, or roebuck. In the year 1183, Bishop Pudsey caused a survey to be made of the various estates of his see in the county of Durham, with a specification of their respective tenures, rents, and services. This survey is generally called the ‘ Boldon Book/ Boldon being the first place mentioned in it. From entries in this book, it appears that the early Bishops of Durham were mighty hunters, and their tenants often held lands by the service of protecting the deer, and furnishing horses, grey- hounds, and other dogs for the chase. It appears, moreover, that the villani and farmers were wont to assemble from time to time at the summons of the Bishop, for the purpose of constructing ‘ haies/ and assisting at a roe-hunt : — 1 Omnes villani de Aukelandschire scilicet dc North Avkeland et West Aukeland et Escumba et Newtonci . . . faciunt partem sucim de haia circa logias. . . . Procter ecc omnes villani et firmarii emit in “ rahunt” acl summonitionem Episcopi ’ f In this same county is a place called Beshope, otherwise Beshoppe and Bosheppe,t i. e., Boe’s hop, or jump, in all probability indicating some famous ‘ deer-pass 9 in the days when these animals were common in Durham. So also in Lancashire, its former occurrence in Bowland, says Whitaker, is pretty plainly indicated in the perambulation by the word ‘ roe-cross/ In ancient charters conveying the royal license to enclose certain forest-lands, or to hunt in particular counties or dis- tricts, the Boebuck is sometimes mentioned amongst other animals which might be enclosed or hunted. Thus from a charter of liberties granted by King John, when Earl of Morton, to the inhabitants of Devonshire, it appears that Boe-deer at that date were included amongst the beasts of chase in that county. This deed, the original of which is still preserved in the custody of the Dean and Chapter of Exeter, is under seal, and provides, inter alia} as follows : — ‘ Quod habeant canes suos et alias libertates, sicut melius et * See Fenland Past and Present , p. 356. t The Boldon Book, p. 26 (Surtees Society), and Raine, Ilist. Acct.of the Episcopal Palace of Auckland, p. 5. X The Boldon Book, p. 6. 140 POPULAR SCIENCE REVIEW. liberius Mas haberunt tempore ejusd. Henrici regis et reisellos- suos, et quocl capiant capreolum, milpem, leporem, etc., ubicumque Ma invenirent extra regardum forestce mece’ It will be observed that tbe word here employed is ca~ prcolus ; in many old grants, however, tbe term used to desig- nate tbe Roebuck is caprea , wbicb, from its similarity to capra , bas led some translators to suppose that tbe goat was intended. But, in the first place, tbe context usually shows that tbe animals included in a licence to bunt, or to enclose, are beasts of tbe forest or of chase, while the goat does not fall within either category, being rather an animal of the hillsides and mountains ; and, in the next place, contemporary translations of such pass- ages go to prove that, even in cases where the term em- ployed is capra , or caper (perhaps so written in error by the transcriber), the animal so designated is evidently the Roe- buck.* In the time of Edward III., there were plenty of Roe-deer in the ancient forest of Pickering, in the North Riding of York ; and in 1340 a prosecution by the Crown was instituted against Henry de Percy, lord of the adjacent Manor of Semere, for allowing his woodward to carry a bow and arrows, and chase and take Roe-deer within the limits of this forest. It appears, however, that the defendant established a right of free-warren, and pleaded that the Roe was a beast of warren and not of the forest.-f* Perhaps it was on this case that Lord Coke relied, in holding the Roe to be a beast of warren, a decision opposed to the opinion of many old English writers on venery, who included this animal amongst the beasts of chase. We learn from Holinshed, that in Henry the Fifth’s time (1413-22), deer were so numerous in England as to be very destructive. ‘ Although/ he observes, ‘ of themselves they are not offensive at all, yet their great numbers are thought to be very prejudiciall, and therefore justly reproved of many. Of these also the stag is accounted for the most noble game ; the fallow deere is the next, then the roe, of which we have indifferent store.’ The author of the ballad of ‘ The Battle of Otterbourne 7 was guilty of no anachronism, when in the following lines he introduced the Roe as one of the characteristic animals of Northumberland in 1388. * A case in point is furnished by John of Trevisa’s translation of the Polychronicon of ltanulphus Higden, to which we shalhpresently have occa- sion to refer. t Placita coi'am Pege apud Westm. Term HU. 13 Ed. III. Rot. 106, Ebor. FORMER EXISTENCE OF THE ROE-DEER IN ENGLAND. 141 * The roo full rekeles ther sche rinnes To make the game and glee, The fawkon and the fesaunt both Amonge the holtes on hee.’ For, a hundred and fifty years later, Leland was able to testify that this animal was then still common in the north of Eng- land. He remarks in his Itinerary , ‘ In Northumberland, rs I heare say, be no forests except Chivet Hills,* * * § and there is great plenty of redde deare and row-bukkes/ According to a Report of Eoyal Commissioners furnished to Henry VIII. in 1512, there were nearly 6000 head of deer, Red, Roe, and Fallow, in the forests and parks of the Earl of Northumberland in the northern counties, at which date there were Red- deer in the forest of Rothbury.f About 1530-34, as we learn from the Durham Household Booh, Roe-deer were to be found in the adjoining county. Thus at p. 142 we find the entry: — * Et Eduardo Denynge et Johanni Greynsweyrde, per 4 dies apud Muglesicyk [Muggleswick] deferentibus 4 roys in regardis . . . . . . . .12 d* Here it is evident from the context that Roe-deer are in- tended, for the entries which precede and follow this all relate to venison brought in. At times the Latin name is bestowed, but generally the English ; thus we find : — {Et famulo Abbatis de Fountand deferenti 1 buh bursario. 3s. 4 d* * Et Thomce Harper deferenti damam domino Priori, Dominica prima Adventus a Roberto Crosby . . . 20^/ 1 Et Lionello Smyth et Eduardo Denynge deferentibus 1 stage a, Mugleswyk ....... 20s/ The existence of Roe-deer in Wales was noted by Leland in Henry VIII. ’s time ; and Camden has noticed several Welsh localities which from their name seem to indicate former haunts of this animal, as Bryn-yr-Iwrch, Phynon-yr-Iwrch, Lhwyn-Iwrch, &c. Pennant informs us that, according to Dr. Muffett, they were still to be found there in the reign of Elizabeth.;]; On turning to Dr. Mufiett’s work,§ we find the bare statement (p. 75) that ‘ the Alps are full of them in high * It is curious that Leland should have made this statement, for beside •Cheviot, there were in Northumberland the forests of Rothbury, Redesdale, Eresdon, Lowes (anciently Loughs, from the number of lakes in it), Allen- dale, and Knaresdale. t Wallis, Nat. Hist, and Antiq. of Northumberland (1769), vol. i. p. 410. t British Zoology, vol. i. p. 59. § Health's Improvement, by Dr. Thomas Muffett, corrected and enlarged by Christopher Bennett, 1655. The author died in 1590, but it does not appear that there was any earlier edition of his work than that of Bennett, who probably revised the original MS. See Wood’s Athence (ed. Bliss), vol. i. p. 575. 142 POPULAR SCIENCE REVIEW. Germany, and some of our mountains of Wales are not without them. 9 It is to be regretted that Dr. Muffett did not particularize the localities in Wales where he supposed the Doe- deer to exist, for a contemporary of his expresses a very different opinion. George Owen, of Henllys, writing of the wild animals of Pembrokeshire in his time (1595), informs us that ‘ for Poes, the countrey yeeldeth not any, neither did I ever heare of any by reporte of the auncient men, to have been usual in this countrey. ’ * One of the most interesting records which we have met with in the course of our researches on this subject, is that which relates to the transport of some Poe- deer from Cumber- land to Surrey in the reign of Charles I. The king had ex- pressed a wish to have some turned out at Wimbledon in one of the royal parks, and application was made to Lord William Howard of Haworth Castle, Cumberland (where we may pre- sume Poe- deer were then common), to have some caught and sent up. Directions for this purpose were accordingly given, and what followed may be gathered from the following entries, in the Household Book of the owner of Haworth : — * 1633, June 29. — To severall persons for takeinge 31 Poe- kidds, as appeareth by bill . . vijli xijs vjd/ They were, no doubt, taken in a 4 haie * with nets, according to the ancient practice ; and after being kept in an enclosure for a fortnight until they had got more tame and accustomed to confinement, they were ready to be moved to London. This was accomplished by means of three carts, as we learn from the next entry : — ' 1633, July 16. — To Wm. Lancaster the Smith, for bind- ing 3 payre of wheeles with iron which carried Poes to London ....... vli xvjd.’ And subsequently on the return of these carts : — 'For repairinge 3 cartes sent with Poes to London to Hinge Charles thether and home again . . xvs. xd.’ How these animals fared in their new home in Surrey we are not accurately informed ; but it may be surmised that they throve and did well, for a few years later, viz., on January 17,. 1639, a warrant was issued to Sir Henry Hungate for 'the preservation of His Majesty’s game of Poe-deer broken out of Ilalf-Moon Park, Wimbledon, and now lying in the woods adjoining thereto, and to take care that no person hunt, course,, or use any net or gun, within four miles of the said park.’f When the Poe-deer became extinct in England is not quite * For some notice of this writer and his MSS., see Fenton’s Historical Tour through Pembrokeshire, 4to, 1811, pp. 524, 562, 563 note, and Appendix, , p. 54. t S. P. Dorn. Charles I. ccccix. 105, Docquet. FORMER EXISTENCE OF THE ROE-DEER IN ENGLAND. 143- certain. In Percy’s Beliques of Ancient English Poetry, in a footnote to the passage in the ‘ Battle of Otterbonrne 9 above quoted, it is stated that Boebucks were to be found upon the wastes not far from Hexham in the reign of George I., and that Mr. Whitfield of Whitfield is said to have destroyed the last of them. This is probably the instance referred to by Scott in his British Field Sqjorts, who states (p. 381) ‘ that the last of its race in England was, it seems, killed in Northum- berland about seventy years ago ; 1 but, if so, his book having been published in 1818, he would have been nearer the mark had he said ‘ ninety 9 or even 4 a hundred years ago.’ An exceptional instance, however, of the capture of a wild Boe in Northumberland, occurred early in the present century, and is thus recorded by Bewick in his History of Quadrupeds (ed. 1807, p. 148) : — ‘ Some years ago one of these animals, after being hunted out of Scotland, through Cumberland, and various parts of the North of England, took refuge in the woody recesses bordering upon the banks of the Tyne between Prudhoe Castle and Wylam. It was repeatedly seen and hunted, but no dogs were equal to its speed; it frequently crossed the river, and either by swiftness or artifice eluded all its pursuers. It happened during the rigour of a severe winter, that being pursued, it crossed the river upon the ice with some difficulty, and being much strained was taken alive. It was kept for some weeks in the house, and was then again turned out, but all its cunning and activity were gone; it seemed to have forgotten the places of its former retreat, and after running some time, it laid down in the midst of a brook, where it was killed by the dogs.’ The late Prof. Garrod, in his recently published account of the J Ruminantia in Cassell’s Natural History , vol. iii. p. 63, states that the Boebuck ‘ still survives in the woods of West- moreland and Cumberland/ but gives no authority for this statement, nor any further particulars. The species had probably been extinct in England for some years, when Lord Dorchester, in 1800, turned some out in the woods at Milton Abbey, Dorsetshire, from whence their de- scendants dispersed in a very short space of time, especially in a south-westerly direction. They were frequently hunted, and afforded excellent sport. About 1829, when the Master of the Hounds, Mr. Pleydell, gave up his pack, after hunting Boe-deer exclusively for sixteen years, he permitted Mr. Drax, of Charboro Park, to capture several of these deer and turn them out in the Charboro Woods. From this second centre they increased in numbers, and wandered far and wide, — from Moreton to Warmwell in the valley of the Frome, and from Hyde to Houghton in that of the Puddle. Their extreme 144 POPULAR SCIENCE REVIEW. eastern extension at present is Lychett, and they have been met with as far west as Hook Park. Mr. J. C. Mansell Pleydell informed the writer, that in 1879 he estimated there were no less than 120 head in the Milton, Whatcombe, and Houghton Woods, which fringe the southern side of the Yale of Blackmore, from Stoke Wake to Melcombe Park and the Grange Wood westward, the number being merely a question of preservation or non-preservation.* fiha.fi n, in his Anecdotes of Cranbourn Chase , mentions the Hoe-deer as an animal indigenous to that part of the country ; but as his book was not published until 1816, it seems possible that the presence of the Hoes in Cranbourn Chase (where a few are still to be found) may have been due to Lord Dor- chester’s experiment commenced six years previously. At all events, Chafin says nothing of the existence of the Hoe-deer in the Chase prior to 1800. Dorsetshire is now the only county in England, it is believed, where Hoe-deer still exist in a wild state ; not because the ancient race have survived there till now, but because, as we have seen, it was reintroduced at the commencement of the present century, by turning out a few brace procured from Scotland.*!* In 1810 there were a good many Hoe- deer in the woods belonging to the Earl of Egremont at Petworth, Sussex. A skull of one of them (a female, with rudimentary horns) was presented in that year by Lord Egremont to the Museum of the Hoyal College of Surgeons, where it is still preserved (Ho. 3598 d),$ and the abundance of Hoes in the Petworth woods at that date, is proved by his lordship’s letter which accompanied the specimen referred to, and which is printed in the Museum Catalogue of Monstrosities, part v. p. 17. The writer has been recently informed by Lord Leconfield, the present owner of Petworth House, that there is a tradition to the effect that the Hoe-deer were introduced there, and were not the descendants of an ancient stock. About thirty years ago, some were sent as a present to Prince Albert, and were turned out at Windsor, where a few are still preserved in the neighbourhood of Virginia Water. Those which still survive at Petworth are kept in the park, which being surrounded by a * See The Zoologist, 1879, pp. 120, 170, 209, 262, 301. t In addition to the information given on this point in The Zoologist for 1879, above quoted, the reader will find further details in The Sporting Magazine for 1817, in Scott’s British Field Sports, p. 381, and in Gilpin’s Forest Scenery (ed. Lauder), vol. ii. p. 301. X This skull is figured in the Proceedings of the Zoological Society, 1879, {). 297, in illustration of some remarks on female deer with antlers, by the ate E. K. Alston. FORMER EXISTENCE OF THE ROE-DEER IN ENGLAND. 145 I wall fourteen miles in length, affords them unusual security and yet abundant liberty. In Scotland, the Roe-deer was once much more common than it is at present, although it is still plentiful in some parts of the country, and has even increased of late years. It is believed that the increase of plantations in the south of Scotland has been the means of spreading it much further in that direction than it used formerly to he found. In Ireland the Roe-deer is unknown, and since no remains of it have been discovered, it seems probable that it was never indigenous to that country, although some have asserted other- wise, on the authority of Bede. John of Trevisa, however, in his translation of Higden’s Polychronicon , observes : ‘Beda seith that there is grete hunty nge of Roobukkes (caprorum is the word used by Higden), and it is i-knowe that Roobukkes beeth noon there. It is no wonder of Beda, for Beda knew nevere that ilond with his eyes ; hot som tale tellere told hym suche tales.’ * On the other hand, if the testimony of Ossian be admitted, it would seem that the Roe was not uncommon formerly in Ireland. There are many very striking passages in which that poet adverts to the hunting the Roe- deer there. He thus pictures the animal’s haunts : — ‘ Lumon of foaming streams .... the dun Roe is seen from thy furze ; the deer lifts his branchy head, for he sees at times the hound on the half-covered heath.’ Temora , book vii. Again : — 4 The king rejoiced as a hunter in his own green vale, when after the storm is rolled away, he sees the gleaming sides of the rocks. The green thorn shakes its head in their face ; from their top look forward the Roes.’ Temora , book viii. Strange to say, also, the Roebuck is mentioned as a native of Kerry in an Irish MS. poem of the ninth century, which is thus referred to by the late Sir W. Wilde : f ‘ In the collection of Irish MSS. preserved in the Library of the University of Dublin, is a very curious zoological and topographical poem, the original of which is believed to be as old as the ninth century ; it is certainly one of the most re- markable productions of its kind known in any language in Europe of the same date. The history of this poem is as follows : — Finn Mac Cumhaill was made prisoner by Cormac Mac Art, monarch of Erin, who, however, consented to liberate him when a ransom of two of every wild animal in Ireland — a male and female — were brought before him on the green of Tara. Cailte Mac Ronain, the foster-brother and favourite of the * See also The Book of Hoivth, Brewer and Bullen, Calendar Carew MSS. t Proc. Roy. Irish Acad. vol. vii. p. 182. NEW SERIES, VOL. V. NO. XVIII. L 146 POPULAR SCIENCE REVIEW. celebrated Irish general,* having first performed many remark- able feats at Tara in the king’s palace, undertook and succeeded in accomplishing this apparently hopeless task within a twelve- month ; and in this poem is said to have related to St. Patrick the result of his mission. There is, perhaps, no other example in the Irish language of the same extent containing so many words — names of animals — of which the meaning is not known ; and there are but few poems of so many lines requiring the same amount of topographical annotation. The names of several animals are, as stated, untranslatable ; either the animals themselves have become extinct in Ireland, or they are now known by other names than those preserved in the MS.’ As a specimen we quote the following lines : — f * I then went forth to search the lands, To see if I could redeem my chief, And soon returned to noble Tara With the ransom that Cormac required. * Two foxes from Slibh Cuilinn [co. Armagh], Two wild oxen from Burren [co. Clare], Two swans from the dark wood of Gahhran,f And two cuckoos from the wood of Fordrum.’ The most remarkable line, however, so far as concerns our present inquiry, is that which relates to the bringing of two Roebucks ( Earbog ) from Luachair Deaghaidh, i. e., Slieve Lougher, Co. Kerry. We are not informed upon what authority the word Earbog is rendered ‘ Roebuck.’ It seems not a little curious that the Irish in the ninth century should have had a name for an animal which, it is supposed, was never indigenous to Ireland ; at the same time, it should be observed that the Irish name, Earbog, closely resembles the Gaelic names for this animal (Earb, Earba, Earb-boc) in use at the present day. It is worthy of remark, too, that in the Museum of the Royal Irish Academy, amongst the collection of Irish Red-deer horns, is a small specimen catalogued as * No. 45, a small shed horn, apparently of the Roebuck, presented by Joshua Ferguson, Esq.’ Not having seen this specimen, we can express no opinion upon it ; but if it be really the horn of a Roebuck found in Ireland, its history would bo worth tracing. * See Annals of the Four Masters, under a.d. 286. t A translation of this poem appeared in the Dublin University Magazine, March 1854, and the Irish version, with the translation opposite, is given in the seventh volume of the Proceedings of the Royal Irish Academy, 1859, pp. 184-191. \ Now Gowran, co. Kilkenny. 147 CONTRIBUTIONS TO THE KNOWLEDGE OF THE HOTTENTOT RACE. By M. J. A. ROORDA SMIT* DIFFERENT travellers who Lave had the opportunity of comparing the Hottentots and the Chinese, have found a great analogy between the two races. The first who remarked it were the old colonists of the Cape, who even gave to some tribes the name of ‘ Chinese Hottentots/ In England, also, John Barrow drew attention to this singular fact.f When, at a later period, Chinese coolies arrived at the Cape, their resemblance to the Hottentots was found to be striking, and led to frequent errors. Wood speaks of a traveller who believed that he had a Hottentot servant, and who discovered, only after some time, that the man was a Chinese.^ During my stay in South Africa, I have been more than once witness of similar facts. At the Cape, for instance, I have seen a Chinese and a Hottentot both serving in the same hotel ; as they were dressed almost in the same style, we were con- stantly confounding them, taking the Asiatic for the African, and vice versa. At the Diamond fields I met with a case of the same kind. In order to give a general character of the Hottentots, I cannot do better than quote the following passage from Yon Siebold : ‘ The breadth and coarseness of the face, the promi- nence of the cheekbones, the development of the jaws, the flat- tened form of the bridge of the nose, and the enlarged nostrils, the size of the mouth, the thickness of the lips, the apparent obliquity of the eyes, the stiff, abundant hair of a brownish - black colour, or inclining towards red, the heaviness of the eye- brows, the scarcity of the beard ; and lastly, a wheat- coloured, yellowish- red complexion distinguish them,’ &c.§ * From the Archives Neerlandaises des Sciences exact es et naturelles, tome xv. livr. 5. t Barrow, Voyage to Cochin China. X Natural History of Man, p. 241. § Prichard, Nat. Hist, of Man, vol. i. p. 232 ; Catalogue du Musee Trolik, par Dusseau, p. 32. 148 POPULAR SCIENCE REVIEW. I need only remark, concerning the hair, that among the Hottentots it is curly and does not cover the head uniformly ; it forms patches separated by bare spaces. Moreover, as re- gards the complexion, the expression, ‘ yellowish-brown/ would be more suitable, at least in certain cases, than ‘ yellowish- red/ How, in giving this description, Yon Siebold did not refer to the Hottentots, but to the Mongols who inhabit the Corea, a country tributary to China. Hr. Carpenter describes the Hottentots in the following terms : ‘ Thus the face presents the very wide and high cheek- bones, with the oblique eyes and flat nose of the northern Asiatics ; at the same time that, in the somewhat prominent muzzle and thick lips, it resembles the countenance of the Hegro. The hair is woolly, like that of the Hegroes, but it grows in small tufts scattered over the surface of the scalp (like a scrubbing-brush) instead of covering it uniformly ; thus re- sembling in its comparative scantiness that of the northern Asiatics.’ * A long time before the Hutch East India Company had taken possession of the Cape, vessels of other nations had already dropped anchor in Table Bay and made the acquaintance of the inhabitants of the country (1497-1652). But the ac- counts of these voyages, of which the sole aim was commerce, give us little information about the inhabitants. The Portuguese, who changed the original name ‘ Quai-qua, Khoi-khoiu, Kanimou-qua P * into that of ‘ Saldanhas/ learned more than once, to their cost, that the population, though weak and not numerous, could defend itself and was vindictive. (1497, Vasco de Gama; 1510, Francisco d’ Almeida ; 1516(F), Emmanuel de Souza.) The Hutch and English had rather less to complain of. (1598, John Havis; 1601, English East India Company and Paul de Corniden ; 1608, Maaklof; 1648, Leendert, Jansz. and Hie. Proot, Van Biebeek.) The natives of the Cape received from the Hutch the name of ‘ Ottentos/ which has since become ‘ Hottentots/ At the time when the Europeans became acquainted with them, they were nomads, who changed their abode continually and lived in ‘ kraals/ the huts of which were easy to take down and put up elsewhere. They were acquainted with metals — at all events with iron — which they knew how to work. Their acquaintance with this metal, however, does not seem to have been very general, as it was considered a precious article, although iron ores are not rare at the Cape, particularly in Hamaqua-land. Carpenter, Physiology, fifth ed. p. 897. CONTRIBUTIONS TO THE KNOWLEDGE OF THE HOTTENTOTS. 149 In 1601, the ships of the English East India Company obtained sheep and cattle in exchange for pieces of old iron. Their weapons were the bow and arrow. When, later on, they came in contact with the Catfres, they adopted from them the ‘zagaie.’ At the time of the voyage of Le Yaillant (1781), the use of this weapon had spread very little among them, and the Hottentots, who already possessed ‘ zagaies ’ had not yet learned to make use of them very cleverly. Their clothing consisted of dressed skins, more or less ornamented. They knew very well how to remove the hair from skins. A peculiarity which is also found among the Caffres, is the circular form of their huts and of their camps. It seems that no South- African race can easily draw a straight line. The geographical distribution of the Hottentots is often described incorrectly. To judge of it from my own re- searches, they must have originally inhabited the south-west side of the Cape, that is to say , only the coast region ! While the Hottentots were in possession of the western part of the Cape, the Caffres occupied the eastern part (1500, Cabral). The shipwrecked sailors of Souza’s ship reached on the east (eastern coast) an Ethiopian village where they embarked. We cannot here imagine any confusion with the Hottentots, seeing that the sailors in question knew the latter perfectly, having seen them before. In 1684 an expedition of thirty-nine Boers found, in the eastern part of the Cape, some Caffres who had never yet seen a white man. It seems that the Hottentots at that time had no knowledge of the neighbourhood of the Caffres. It was probably about 1700 that they came in contact with them. From these connexions have resulted the mixed races of the ‘ Gonaqua ’ and the ‘ Gonaquebi.’ When Le Yaillant travelled amongst the Gonaqua (1781), they did not seem to remember their true origin. The nature of the soil obliged the Hottentots to keep near the southern coast. Further north they would have come upon the great plain of the Karrou, which, from the want of water and good pasturage, would not have suited their cattle at all. So when Le Yaillant visited the Karrou, he found there no other population besides Bosjesmans and Souzouana. By this last name he designates also Bosjesmans, not Bechuanas. While the Quaiquas occupied the most southern part of the country, they were in contact in the north with the Korannas. Le Yaillant met with the latter in their original station. But towards 1790 they emigrated towards the interior, and estab- lished themselves on the territory of the Transvaal, at the part where the Hart’s Biver falls into the Yaal. The old chief, Mossou Byt Taaibosh, stated, in 1872, to M. Burgers, who was then President of the Transvaal, that when he was about four- 150 POPULAR SCIENCE REVIEW. teen (at tlie time of tlie declaration lie was over a hundred) he had set out with his tribe, which had previously inhabited the coast.* To the north of the Korannas, and to the north and south of the Orange river, dwelt the Namaquas. These people, visited for the first time by Yan der Stell (1685), appear to have mixed with more northern tribes (not Hottentots), especially with the Damaras ; so that the actual representatives of these latter would be partly their descendants. There exists, at least among the Damaras, a legend, according to which they had, as first ancestors, a Namaquan father and ( horribile dictu !) an ape mother. This legend, which has been told me by hunters, is also spoken of by Wood.-f* The Bosjesmans are at present sufficiently recognized as Hottentots. All the Hottentot tribes seem to have furnished their contingent to these pioneers. Nevertheless, there is room for thinking that, besides these deserters, they also comprise original tribes ; and Le Yaillant even regards these as true and pure Hottentots. They penetrated further than all the others into the Karrou. They were not nomads, but they lived ex- clusively by hunting. It was probably at a more distant period that the Bosjesmans (Sa-an or Sa-qua) separated from the other Hottentots. They feared the more northern tribes ; as for those who lived more to the south, they seem to have known them but slightly or not at all. We find on this subject the following curious passage, dated the 24th April, 1654, in the journal of Yan Biebeek, the first governor of Cape Colony : ‘ To-day a dead Bosmanneken was found in the mountain, such as is called in Batavia an Ourang-outang. He was about the size of a small calf, with long and hairy arms and legs, and of a dark- grey colour. Forced by hunger, our people ate him/ j I must add, in defence of Yan Biebeek, that at this time his relations with the neighbour- ing Hottentots were not at all friendly, so that he could not gain from them any enlightenment. The Bosjesmans have always been driven back towards the interior of the country. Nowadays we meet with them nowhere but in the mountains of Basutoland, and in the plains of the Kalihari. The Hottentots have never been a powerful people. Ac- cording to the census of 1865 they numbered 81,600 in Cape Colony. Taking all the tribes together, I think we may estimate their total actual numbers at 270,000, perhaps at * Correspondence between Thom. Fr. Burgers and Sir Henry Barkly. t Wood, Nat. Hist, of Man. X Hall, Manual of South African Geography, Chron. Tables. CONTRIBUTIONS TO THE KNOWLEDGE OF THE HOTTENTOTS. 151 300,000. It is possible that formerly they may have been more numerous, but the difference cannot have been great. They have never suffered very greatly from either war or epidemics. Moreover, considering the climate, the polygamy that was customary amongst them, etc., circumstances were favourable to their multiplication. I think there is good reason for supposing that in 1500 their number was much smaller than at the present day. They had been unable, before the establishment of the Dutch Colony, to drive back the wild beasts, so dangerous to them and to their flocks. Lions, for instance, were still, in 1563, so numerous on the coast of Table Bay that Van Riebeek wrote in his journal, 4 This night one would have said that the lions were inclined to take the fort by storm.’* Though inhabiting the coast in 1500, and even later, they possessed no knowledge of navigation ; so that they had no communication with Robben Island, which was situated opposite Table Bay. The different tribes of Hottentots may be divided into, 1st, Quai-qua, or true Hottentots ; 2nd, the Nama-qua ; 3rd, the Koranna, Kora, or Kora-qua ; 4th, Sa-an, Sa-qua, or Bosjes- mans ; 5 th, Gonaqua and Gonaquebi — mixed races produced by a mixture of Caffres and Hottentots ; 6th, Griqua, a mixed race, one issue of white fathers and Hottentot mothers. Hybrids of Hottentots and white women have never been noticed, as far as I know, and probably they do not exist. The Griquas united about 1780-1790 into tribes, which abandoned the Cape Colony, and established themselves in the territory now forming the Vrystaat (Free State) and in Griqua- land West. More recently, somewhere about 1850, many of the Griquas returned towards the coast in the district called Griqua- land East, and formerly known by the name of Memandsland (N o-mans-land) . All the tribes, including the Gon aquas and the Griquas, belong by their physical characteristics and by their language to the same natural group. On the similarity of the language I must remark that the dialect of the Gonaquas is a mixture of the Caffre and Hottentot dialects, and that most of the Griquas speak Dutch. The language of the Bosjesmans is the poorest of all; one might call it degenerated Hottentot. This fact is easily ex- plained by the very primitive way of life of these pioneer hunters. An analogous example of degeneracy in language and physical characters may be observed now on the north-east borders of the Transvaal, among the Vaalpen Caffres, remnants of the great tribes of the Bechuanas, which have been exterminated * Hall, Manual of South African Geography, Cliron. Tables. 152 POPULAR SCIENCE REVIEW. by more powerful neighbours. To these Yaalpens, the name of Bechuana-Bosjesmans might very well be given. A character- istic feature of the Hottentot dialect is the use of ‘ dies/ of which the Korannas particularly make very frequent use. These dialects differ essentially from the Caffre dialects. Often, indeed, it has been believed (particularly in Cape Colony) that there existed a relationship between the two languages ; and some even considered the Hottentot as a modified Caffre dialect. But this opinion is altogether erroneous. Before 1500 the Hottentots had seldom, if ever, come in contact with the Caffres. The origin of the error in question is easy to discover. When the Hottentots entered into relations with the Caffres there resulted the mixed races of the Gonaquas and of the Gonaquebis, which both of them, and particularly the latter, spread among the Galeka Caffres. Thus the ‘ dies ’ and some Hottentot words were introduced into the language of the Galekas. But these ‘ dies ’ are only met among those Caffres who border on some Cape Colony, and among the Basutos (in greater part Bechuanas), who about 1830 constituted a distinct people and admitted among them some fugitive Hottentots. Among the other Caffres, for example among those of Natal and Zululand, no trace either of the ‘ dies/ or of the other peculiarities of the Hottentot languages, are found. They are equally strangers to the language of the Bechuana, es- tablished to the north of the Transvaal. For some time, however, the ‘dies’ appear to have a ten- dency to spread particularly in the south of Natal. As the Gonaquas also moved amongst the Hottentots several Caffre words have obtained a footing in the Hottentot language. The Korannas, after their immigration into the Transvaal frequently mingled with Bechuana tribes (black), and this has also dimi- nished the purity of their language. In Cape Colony many, if not most of the Hottentots, speak nothing but Dutch, and no longer know their original language. This language is still spoken only and exclusively by the Bos- jesmans and the Namaquas. But these have likewise been in more and more frequent contact with the whites and other races. In fifty years their language will perhaps have entirely disappeared. I have made some researches on the question of the distri- bution of the races at the Cape, a question which interested me especially. Its study is rendered very difficult by the very fre- quent change of abode of the different tribes, and as besides I have only incomplete materials at my disposal, the results obtained must be looked upon as merely tentative. These results may be summed up as follows : — 1. The central CONTRIBUTIONS TO THE KNOWLEDGE OF THE HOTTENTOTS. 153 part of the Cape countries, now known by the name of Xarrou, as far as the Orange River, of Yrystaat, of Griqualand West, and of Kalihari, was formerly uninhabited and visited only by the Bosjesmans. From about 1790 the Yrystaat and Griqualand- West were colonized by Xorannas and Griquas, and a little later by Bechuanas (Barolongs, Bawanketsis, &c.). The Korannas and the Griquas came from the Cape Colony, taking a direction from south to the north ; the Bechuanas arrived from the north — probably from the northern part of the Transvaal. 2. The eastern part of the Cape, to the south of the Storm- bergen, along the coast, and to the east of the Drakenbergen (which are a continuation of the Stormbergen), was already inhabited in 1500 by Caffres (British Caffraria, hiatal, &c.). 3. The Transvaal was also early inhabited, particularly the northern part, by Bechuana tribes, who were always moving towards the south (1600 P). 4. The country to the west of the Transvaal, which Living- stone and others have mentioned by the name of ‘ Sechele’s Country/ was only colonized towards the year 1824 by Bechuana tribes (among which were the Makololos, who have since been moving again towards the north), which had been driven away from the Transvaal by the Matabeles of Moselekatse. The Bechuanas and the Caffres seem to have come from more northern parts of Africa. They show a certain analogy of characters. Their movements were effected parallel to one another from the north to the south ; the Caffres pro- ceeding along the coasts, the Bechuanas across the central region. To the south of the Limpopo they were separated by the Drakenbergen, so that the Caffres remained to the east of this mountain range, and the Bechuanas to the west. Both these races are black, and we often find among them, especially among the Bechuanas, Arabian and Jewish types. 5. Basutoland, which was formerly entirely uninhabited, was colonized only in 1830 by Bechuana tribes coming from the Transvaal, and by a small number of Fetcannets (the present Fingoes of the Cape Colony, who before 1820 were Caffres of Ratal), of Korannas, of Bosjesmans, &c., whom the chief Moshesh united into one people, under the name of Basutos (1830). 6. The country situated between the two rivers — the Lim- popo and the Zambesi, to the north of the Transvaal — was originally occupied by Bechuanas, but later on, after 1836, it was invaded by Caffres — the Matabeles of Moselekatse, who left the Transvaal, and took a direction across Sechele’s country, at first towards the west, afterwards towards the north, and still later towards the north-east. In the country of Moselekatse (or rather of his successor, Lo-bengula) some 154 POPULAR SCIENCE REVIEW. missionaries (Merensky, &c.) have sought the Ophir and the Saba of the Old Testament. Maude has there discovered the grand ruins of Zimbaye. The traces of human industry which I have found myself in the Transvaal belong to a rather recent date. Such are several old copper-mines (with quartzose gangues) in the Makhali mountains, a range of quartz porphyry, which, at about six English miles to the north of Pretoria, runs from the east to the west. Such are further old lead-mines, which I have found in the Waterberg district, about eighteen English miles to the north-east of the Nylstroom. Galena, rich in silver, is there disseminated in a vein of quartzite, which has been worked very methodically by open workings. Neither the Bechuanas nor the white population of the district knew by whom, or at what period, these works had been executed. I presume that they are to be ascribed to the Portuguese, who had very early taken footing in South Africa, and who followed trade. The general conclusion from these researches is, that the Hottentots did not occupy the central part of the Cape. As the fertile plains of the Transvaal and of the Yrystaat were formerly uninhabited, they would have been able to live there quietly, just as well as elsewhere, if they had arrived in the south by this way. I have reason to suppose that the south and the east of the Cape countries ought to be considered as their original abode. Thus we find, in the fifteenth century, in the southern part of the Cape, a yellow race, amounting to from 200,000 to 300,000 souls, bounded on the north by black tribes (Damara and Ovampo), and by desert places (Karrou, &c.), and in the east also by black tribes (Cafixes). [The author then makes a detailed comparison of the characters and measurements of Chinese and Hottentot skulls, the general results of which he sums up as follows : — ] If it is allowable to draw general conclusions from the measurement of so small a number of crania, we find : — 1. That the crania of the Hottentots are not only dolicho- cephalic, but in nearly half the cases (seven out of fifteen) orthocephalic. In general they are more dolichocephalic than the Chinese crania, the length being in them relatively greater, and the width less. 2. That the absolute height of the Hottentot crania is less than that of the Chinese crania. As the length of the first is relatively greater than that of the second, the index H. L. is smaller in the Hottentots. 3. That the Hottentots are in general less prognathous than the Chinese. CONTRIBUTIONS TO THE KNOWLEDGE OF THE HOTTENTOTS. 155 4. That the height of the face in the Hottentots is less than among the Chinese, the absolute height, as well as the relative (the index H. L.) The points of resemblance between the Hottentots and the Chinese consist in — 1. The width of the bridge of the nose (space between the orbits). 2. The shape and inclination of the orbits. 3. The prominence of the zygomatic bones and arches. 4. The width of the face (taken at different heights). 5. The development of the parietal bosses. 6. The relation between the arcs and their chords. This last character applies above all to the arcs and chords situated in the sagittal plane ; in a less degree to the transverse arcs and chords. If we consult the works of Bhimenbach,* ** of Yan der Hoeven,f of Lucae,+ of Yon Baer,§ of Betzius,|| of Dusseau, of de Koning,H and others, we find indicated as fairly constant characters of the Chinese crania, — 1. A wide bridge to the nose, and a broad flat nose. 2. The facial surface of the upper jaw, but little hollowed, and often even convex (Dusseau). 3. The zygomatic bones and arches very prominent. 4. The parietal bosses well marked, and often very much developed. 5. A curvature with the convexity anterior of the alveolar part of the upper jaw ; a curvature answered to by a similar one in the incisor teeth and their roots. In all these respects the Hottentots resemble the Chinese, as also in the less constant character drawn from the height to which ’the bones of the nose ascend. In both the vault of the cranium very often projects in the median line. In both we find, in most cases, elongated quadrilateral orbits, which incline outwards. The projecting form and outward inclination of the angles of the lower jaw are frequently met with both in the Hottentots and in the Chinese. I must, however, admit that in the Chinese the nose is not so flat as it generally appears to he in the Hottentots. Immediately above the pyriform open- ing the nasal bones are more projecting in the former than in the latter. This difference was perceptible even in the Chinese and Hottentots whom I have seen alive. It follows from this * Decas collectionis , Gottingen, 1790. t Tijdschrift v. not. Geschied, iii. p. 143. t ^ur 0r9- Formenlehre , 1844. § Mem. de VAcad. de St. Petersbourg, x. p. 241. || Ethnolog. Schriften , 1864. Catalogue du Mus4e Vrolik. ** Dissertatie , Leyden, 1877. 156 POPULAR SCIENCE REVIEW. that although the Chinese are in general platyrhinous, they are so in a less degree than the Hottentots. In the second place, the convexity of the facial surface of the upper jaw is met with more frequently in the Hottentots than in the Chinese. The peculiarity of having the angles of the lower jaw curved outwards, cannot be regarded as a race-character. I have met with it pretty frequently in the Caucasian crania of the Yrolik Museum. It must he noticed, moreover, that it exists princi- pally in the crania of men. The crania of women — Hottentot, Chinese, and Caucasian alike — only show it rarely and in a very feeble degree. M. de Honing has studied the anomalies of the sutures of the temporal region in the Chinese crania of the Leyden Museum, namely, the frontal apophysis of the squamous portion of the temporal and the sutural bones developed in the squamous suture which is situated towards the frontal bone. Similar relations, to which M. Virchow is inclined to attach an anthro- pological significance, were altogether wanting in the Hottentot crania which I have had the opportunity of seeing, nor do Messrs. Barnard Davis and Wyman (loc. cit.) mention them in the Hottentots examined by them. In forty-one Caucasian crania in the Vrolik Museum, I have nine times found a sutural bone in the squamous suture, namely, eight times on one side only, and once (in the cranium of an Englishwoman) on both sides. Two of the Caucasian crania were stenocrotaphic. In none have I seen a true frontal apo- physis of the squamous portion of the temporal. The frequency of this sutural hone in the Caucasian crania of the Vrolik Museum is evidently quite a matter of chance. May not the frequency of the frontal apophysis of the squamous portion of the temporal of the Chinese studied by M. de Honing be in the same case ? I must here express my regret that I have not been able to study all that has been written about Hottentot crania. It is therefore very probable that I have neglected some important characters already noticed by other authors. Van der Iloeven was of opinion that the analogy between the Hottentots and Chinese to which Barrow had called atten- tion, only extended to the colour and the direction of the eyes.* Although the similarity in colour and general appearance seems to me to be a fact of very great importance, I think that the cranial characters, in spite of certain differences, equally authorizes us to admit a close affinity between the Hottentots and Chinese. * Tijdschr. v. Nat. Geschied, tome iii. p. 153. CONTRIBUTIONS TO THE KNOWLEDGE OF THE HOTTENTOTS. 157 To check the conclusions which I have found it necessary to adopt, it would be important to compare thoroughly the lan- guage, manners, customs, religion, legends, &c.of the two peoples. The facts which I have been able to collect on these heads are unfortunately but of little significance. Dr. Carpenter, one of the few authors who admit the rela- tionship between the Hottentots and the Mongols, having asked Mr. Norris whether there existed any analogy between the languages of the two races, received a reply in the affirmative : ‘ The affinities of the Hottentot language being rather con- nected, in his opinion, with the languages of High Asia, al- though the connecting links are extremely slight/ (Carpenter’s Human Physiology , 5th Ed. p. 897.) Prof. Schlegel, whom I have consulted on this subject, ad- vised me not to place too much confidence in so vague an assertion, and said that in his opinion the affinity in question would be very difficult, if not impossible, to demonstrate. Supposing, however, that there was no relationship between the two languages, it would still be no sufficient reason for denying the affinity between the races. The Chinese and the I Japanese, who, in an anthropological sense, are closely allied, speak languages so different that there would he great difficulty in discovering the slightest analogy between them. The Ainos justify the same remark. Moreover, the language of the Hottentots, in the course of centuries and under the influence of a number of circum- stances, may have been considerably modified. It is certain, however, that in Africa it has undergone no considerable alter- ation, since, as I have already pointed out, it has remained fundamentally different from the languages of the neighbouring peoples. As I had received from different sources, independent of each other and worthy of belief (among others from the present grand chief of the Korannas, Mossou Kyt Saaibosch), the com- munication of a legend, according to which the Korannas (and consequently also the other Hottentots) had arrived at the Cape • in boats after traversing the sea, the idea struck me that some striking event in the history of the Chinese, or of other Asiatics, had occasioned an emigration. But to the questions which I put on this point to M. Schlegel, the reply was negative. The Chinese in the fifteenth century only knew the eastern coast of Africa as far as Melinda (Dozy). We must notice, also, that at a period already far distant, ; some Chinese, lost at sea, landed on the Isle of Bourbon, where their race is preserved to the present day, fairly pure (there were therefore women amongst them). M. Schlegel writes to me that, according to an oral communication of M. Grandidier, 158 POPULAR SCIENCE REVIEW. these Chinese refer their arrival in Bourbon to the fifteenth or sixteenth century. A French half-caste, whom I met in the Diamond fields of South Africa, gave the date of their establish- ment still earlier. The mythology of the Hottentots leaves us equally in obscurity. Old travellers, Koibe amongst others, have de- scribed with much emphasis the religious ceremonies of the Hottentots. None of these accounts deserves the smallest con- fidence, any more than those of certain missionaries who believed they had made the same observations. Le Vaillant, who of all the travellers to the Cape is most worthy of belief, and whose accounts are most exact and most provable, was unable to observe any trace of religion, either in the Korannas or in the Namaquas. The later researches of M. Bleek on the mythology of the Bosjesmans do not further enlighten us on the subject. The legends and the myths collected by him all relate to the animals of Africa and to the stars of the southern sky. Most, if not all of them, are of very recent date. This is evi- dent, among others, in the myth of the origin of the Moon, which M. Bleek regards — it is difficult to understand why — as among the most ancient. 4 The Mantis threw one of her shoes at the Moon, which made it red (the Moon) because the red sand of the Bosjesmans7 country adhered to the shoe, and cold because the shoe was only made of leather. Thus the Moon is red because she teas covered with the red dust of Bushmanland, and cold because it is only leather / ( Cape Monthly Magazine , xi., 109.) Now I must point out that the ancient Hottentots, although knowing since the sixteenth century how to tan skins, never wore shoes. Further, all the Bosjesmans whom I have seen were barefooted. The only chaussure which is found among them of ancient date (and not even generally) consisted of straps rolled round the lower part of the leg. As for shoes, the Bosjesmans knew nothing of them until they came in con- tact with the Europeans. The legend in question, then, must have been formed afterwards. The first attempts at painting among the Bosjesmans are probably of an equally recent date. The reproductions which Wood gives of them in his Natural History of Man, suggest immediately the idea of • badly- executed sketches of naval officers, recognizable among other things by the peculiar form of their hats. Some hunters assured me they had seen, in caves, early representations of animals. All the Hottentots have a vivid imagination. They speak and sing willingly, but their recitals generally wander far from the truth. It is this which makes me look upon the information CONTRIBUTIONS TO THE KNOWLEDGE OF THE HOTTENTOTS. 159 collected by M. Bleek in bis Bushman’s Researches, as possessing a very problematical value. A new indication may be furnished, I think, by their domestic animals. At the time of the discovery of the Cape the Hottentots possessed both sheep and oxen. Sheep were originally entirely unknown to the Caffres and to the Bechuanas, as also, if I am not mistaken, to the Damaras and to the Ovampo. The indigenous race of sheep of the Hottentots, which has at present, perhaps, entirely disappeared from the Cape countries, was the sheep with a big tail, identical, apparently, with the Ovis platyura. This Ovis platyura, from what I have heard from Mr. Horst, comes from the hot parts of Western Asia and the south of Bnssia, whence it has been imported into certain parts of Africa. The Hottentots were in possession of this sheep before the arrival of the Europeans ; had they not brought it with them on leaving Asia ? If the identity of the big- tailed sheep of the Cape with the Ovis platyura could be placed beyond doubt, it would be, in my opinion, a very important indication as to the question of the origin of the Hottentots. The possession of this sheep-race proves still more. In the north of the Cape country we do not find any sheep. The middle part, including the northern Transvaal, seems entirely unfit for rearing these animals. Amongst the known causes we can quote the poisonous qualities of the pasturage, the presence of the tsetse fly, and of special pneumonias. It would, therefore, have been difficult, if not impossible, for the Hottentots to move on from the North to the South on the firm soil of the Cape. Cattle were reared by the Caffres and Bechuanas as well as the Hottentots. As to the Caffres, I believe that they possessed particular breeds of oxen (Zulu and Boeskop races) ; as to the Hottentots I have not been able to discover anything of the kind. The Europeans got to know the Hottentots only at the end of the fifteenth century. As I have said already, the popula- tion of the Cape was then only thin. According to an estimate founded on the statements of travellers, I believe that the total of Hottentots at that period did not surpass 200,000. This number, which I should even feel inclined to reduce, is certainly only small for a people, which was, for a long series of centuries, in circumstances so favourable to its multiplication. Moreover, it would be a very strange lusus naturae, that could have produced at the Cape a race so characteristic, so different from all neighbouring people, and showing so much analogy with the Mongolian race. 160 REVIEWS. ANIMAL LIFE* FEW naturalists can claim to speak with more authority than Prof. Semper. A long residence in those rich tropical Eastern countries, the natural productions of which we know chiefly from the descriptions of hurried travellers, or from the researches of scientific expeditions, familiarized him with the structure and hahits of a most varied assemblage of animal forms ; and his previous training enabled him to make good use of the un- rivalled opportunities of study thus afforded him. Accordingly it is no great wonder that his volume of the ‘ International Science Series,’ lately published, should he unquestionably one of the most interesting contribu- tions to zoological literature that has appeared for years. Holding the doctrine of the evolution of organic forms as proved, Prof. Semper considers that there has been sufficient theorizing on- the subject, and that what we now require is an exact investigation, by observation and experiment, of the processes by which changes are produced in the organism. Thus he says in his Preface : — ‘ The popular cant about “ Biogenetic princi- ples and the falsification of Ontogenesis — the laws of inheritance at corre- sponding periods of fife, or the correlation of organs — Ontogeny and Phylogeny — variability and heredity ” — is put out of court as useless ; for these are merely axiomatic expressions for a sum of identical or correlative pheno- mena, of which the essential nature is in no way revealed by them ; ’ and it is with the view of indicating the road which he thinks should be taken to furnish the true explanation of these generalized expressions that his present book was written. Variability, he thinks, of all the properties of the organism ‘is that which may first and most easily be traced by exact observation to its efficient causes;’ and it is to the phenomena and causes of variation in animals that his book is chiefly devoted. But it has a further limitation. Prof. Semper is of opinion that the action of conditions external to the organism is a much more potent factor in the modification of the latter than is supposed by many naturalists of the so-called Darwinian school, or, in fact, by Mr. Darwin himself, at least in his earlier writings on the origin of species. * The Natural Conditions of Existence as they affect Animal Life. By Karl Semper. 8vo. London : Kegan Paul & Co. 1881. REVIEWS. 161 From this point of view the question of the variability of organisms is treated in a most thoughtful manner by Prof. Semper, and illustrated by the citation of a multitude of examples from all divisions of the animal kingdom, and in many cases founded on the personal observations of the author. In the action of external conditions of existence upon animals, Prof. Semper distinguishes transforming and selective influences ; hut, in his arrangement of his subject, he divides the external agents into those belonging to inorganic or inanimate nature, including under this term the food which, although it may be derived from living organisms, does not become food until after they are dead ; and those due to living organisms, and especially to living animals of other species. Both these series include both transforming and selective influences. Under the former category we have, besides food already mentioned, the influence of light and temperature, that of the condition of the water upon aquatic animals, and of the air upon others, the influence of currents upon the distribution of animals, and some other points ; under the second, the action of parasites and hybridization indirectly transforming animals, and the consequences of the competition among animals in its selective in- fluence on the organisms. In connexion with the influence of water in motion, Prof. Semper furnishes his readers with an exposition of his views on the formation of coral reefs, illustrated especially by his own investigations on the Pelew Islands, which, as is well known, have led him, in opposition to the generally received views of Mr. Darwin, to the opinion that here, at any rate, the evidence is in favour of the occurrence of upheaval of the region during the formation of the reef. So far as the Pelew Islands are concerned, there is no doubt the author makes out a very strong case ; but whether it is an exceptional one remains to be seen. Under any circumstances, his description of the Pelew reefs will be read with much interest. Throughout his little book, indeed, the amount of interesting information on the structure and habits of animals that Prof. Semper lays before his readers is very great ; and the statements in the text are supplemented by a series of most valuable notes on points of detail, forming an appendix. The book is very freely illustrated with well-executed woodcuts, and is certainly one of the most attractive volumes on natural history that has appeared for several years. A POLAR RECONNAISSANCE.* THIS most interesting book is intended by Captain Markham not only as an account of a voyage made by him in company with Sir H. Gore Booth to the seas surrounding Novaya Zemlya, but also as an argument in * A Polar Reconnaissance , being the Voyage of the 1 Ishjorn ’ to Novaya Zemlya in 1879. By Albert H. Markham. 8vo. London : C. Kegan Paul & Co., 1881. NEW SERIES, VOL. V. NO. XVIII. M 162 POPULAR SCIENCE REVIEW. favour of renewed exploration in the Arctic regions, and as an indication of the direction in which he thinks future attempts to reach the North Pole should he made. In furtherance of his general design he prefaces the description of his own voyage with a historical account of the progress of discovery in the region of Novaya Zemlya, which, brief as it necessarily is, contains an exceedingly interesting record of a long series of most gallant attempts to enlarge the knowledge of the geography of these inhospitable regions. As regards the exploration of the region around the Pole itself, Captain Markham is of opinion that the most hopeful direction for further research is along the west coast of the land discovered by the Austrian expedition under Weyprecht and Payer in 1872, and named by them, in honour of their Emperor, Franz Josef Land. The records of former voyages, and Captain Markham’s own experience in the Isbjorn, would seem to show that in August and September in ordinary seasons there would be no difficulty in reaching and exploring Franz Josef Land in a steamer; and as the southern- most point of that land is beyond 80° N. lat., it would certainly seem that in this direction we may with little trouble or delay attain a proximity to the Pole which was only reached with considerable expenditure of time and labour in our last expedition through Smith’s Sound. The Isbjorn, in which Captain Markham and his companion visited Novaya Zemlya and pushed a considerable distance further towards the north, was a little cutter of 43 tons burthen built for Arctic purposes in 1870, and employed by the Austrian explorers, Weyprecht and Payer, in making a reconnaissance preliminary to their voyage in the Tegetthof. The description of the accommodations on board this little craft, and especially of the desagremens caused by the dirty and untidy habits of their Norwegian sailors, is by no means attractive ; nevertheless, the boat, small as it was, seems to have been admirably fitted for the purpose, although apparently rather too 1 lively ’ in a rough sea to be quite agreeable even to a captain in the British Navy. The travellers embarked at Tromso on May 18th, reached Novaya Zemlya on the 9th June, and remained about the shores of that island until the 5th September. They were prevented from navigating the Kara Sea by the presence of ice and the exaggerated idea of the danger involved in encoun- tering it entertained by the crew of their little vessel, especially two harpooners, who were regarded as ex officio authorities on the subject of ice-navigation, and who appear to have been rather pusillanimous when brought into contact with ice in any shape. Accordingly, when the Isbjorn quitted the northern extremity of Novaya Zemlya, her course was taken in a north-westerly direction, with the intention of bearing up towards Franz Josef Land, but ice was again met with about 78° N. lat. and the fears of the crew were again excited, although this time apparently with more reason, as Captain Markham himself seems to have come to the conclusion that there was pack-ice in front of them. On the 12th September, in the midst of ice and with foggy and rough weather, the travellers reached their most northern point in 78° 24' N.lat., or within about 100 miles of the southernmost part of Franz Josef Land ; but here the danger of being caught in the ice in so small a vessel and with only a month’s provisions on board made a quick retreat the most REVIEWS. 163 prudent course that could he adopted, and they sailed in a south-westerly direction to regain Tromso, where they arrived on the 22nd. Another sailing- vessel, the Dutch schooner Willem Barents, under the command of Captain de Bruyne, was engaged in an exploration of these seas at the same time as the Isbjorn, hut was more fortunate, for she met with no ice of consequence on her way to Franz Josef Land, which she sighted on the 7th September. Captain Markham’s narrative of the events of the voyage is very plea- santly given, and as the g-reater part of the time was passed off the shores of Novaya Zemlya, upon which the travellers landed frequently, we get from him a very good account of the scenery of the islands, which is illustrated by several very well-executed woodcuts. Much attention was paid to the natural history of the districts visited, and Captain Markham not only records his observations upon the habits of various animals, especially some of the sea-birds ; but he made considerable collections both of animals and plants which have enabled him to add considerably to our knowledge of the fauna and flora of Novaya Zemlya. Special reports on these collections by several distinguished naturalists are given in the form of appendices at the end of the book, which, from all points of view, must be regarded as an important contribution to the literature of Arctic exploration. HELMHOLTZ’S LECTURES.* PROF. HELMHOLTZ’S reputation stands upon a tripod. It rests, first and foremost, upon his originality as a physicist ; then upon his mathema- tical powers ; and, thirdly, upon his contributions to physiological science. Rarely has a man of such versatility exhibited the profundity of knowledge which Prof. Helmholtz has reached in each of these pursuits. Whether we view him as physicist, as mathematician, or as physiologist, we are equally constrained to admire the rarity of his genius. The work which is now before us contains essays bearing upon each of his favourite studies, and therefore, though small, it will appeal to a variety of readers. The mathematician will instinctively open the volume at the lecture ‘ On the Origin and Significance of Geometrical Axioms;’ the medi- cal man will unfailingly turn to the address entitled ‘ Thought in Medicine ;’ while the student of physics will natually read the eloge on Gustav Magnus, or the lectures ‘On the Relation of Optics to Pointing,’ or the discourse ‘ On the Origin of the Planetary System.’ But these Lectures are not addressed exclusively, or even mainly, to specialists ; they are, as the title indicates, emphatically ‘ popular.’ When Ancient Pistol asks the king, ‘Art thou base, common, and popular V he uses the word as a derogatory expression. But these Lectures are popular * Popular Lectures on Scientific Subjects. By H. Helmholtz, Professor of Physics in the University of Berlin. Translated by E. Atkinson, Ph.D., F.C.S. Second Series. 8vo. London: Longmans, Green, & Co., 1881. 164 POPULAR SCIENCE REVIEW. in the very best sense of the word: — the science is popularized without being vulgarized; the lectures may readily be ‘ understanded of the people,’ while they still retain the true ring of sound science. In fine, they are essays which may be read with relish by every man of culture, whether scientific or not. It is to be regretted, however, that some of the lectures published in this volume have grown rather old, and have thus lost the edge of their interest. Thus the opening discourse on Magnus was delivered as far back as ten years ago ! Dr. Atkinson, the accomplished translator of the Essays, has wisely intro- duced considerable modifications into the last lecture, dealing with ‘ Academic Freedom in German Universities a lecture which, in its original form, con- tained remarks on the Universities of Oxford and Cambridge that could hardly be reproduced at this time in England, and certainly would not reflect the present position of education at those centres. Let us hope that Prof. Helmholtz’s second series of Popular Scientific Lectures will be as well received by English readers as were the first. NATURE’S HYGIENE.* IT is a general belief that the vicinity of a pine-forest is exceptionally healthy, and of late years the Eucalyptus has also been credited with sanitary properties of a very marked character. Mr. Kingzett addressed himself some time ago to the chemistry of the subject, in order to ex- plain, if possible, the hygienic influence of these trees. His researches lead him to attribute their influence to the presence of certain essential oils, which, by their slow oxidation, exert a purifying action upon any malarious exhalations. Under the influence of air and moisture, the volatile oils of the Eucalyptus and of the pine are oxidized, yielding peroxide of hydrogen — a powerful disinfectant — and camphoric acid, which is antiseptic. The oil of turpentine has, apparently, a higher oxidizing power than the oil of euca- lyptus, and hence pines are especially efficacious in rendering a locality salu- brious. Mr. Kingzett’s studies have led him to prepare an artificial substance which he terms ‘ Sanitas ; ’ but a review of a scientific work must not be- come a medium for advertizing a new disinfectant. Suffice it to say, then, that Mr. Kingzett’s researches in Nature’s Hygiene are so clearly put before the public in the present work as to be quite intelligible even to those who are not versed in chemical lore. * Nature's Hygiene : A Series of Essays on Popular Scientific Subjects, with special reference to the Chemistry and Hygiene of the Eucalyptus and the Pine. By C. T. Kingzett, F.C.S. 8vo. London: Bailliere, Tindall and Cox. 1880. REVIEWS. 165 PHYSIOLOGICAL CHEMISTRY .* MEDICAL students have undoubtedly been hitherto at a loss for a handy book of physiological chemistry. True we may point to the fine treatise of Klein, Foster, Burdon-Sanderson, and Brunton ; but few in- deed are the students who have time to read and digest so elaborate a work. What most students require is a neat and compendious book which will serve as a guide in the physiological laboratory and will give them suffi- cient grasp of the subject to enable them to meet the examiner. It is not, now-a-days, enough to have. ‘ read up ’ the subject in a text-book, but the student must show that he has actually seen and handled what he reads about; he must prepare tissues for microscopic examination; he must test the proximate principles of the body ; he must demonstrate the chemical com- position and the characteristic reactions of the various constituents of the tissues and of the nutritive fluids. How is all this knowledge to be acquired in a limited time P Books on histology there certainly are ; but where can the student learn in small compass the pure chemistry of his subject P This is the want which Dr. Ralfe has set himself to supply, and we believe that the little work which he has produced is, in every way, fitted for its purpose. The instructions seem to be clear, concise, and trustworthy ; and every student in a physiological laboratory will find it useful to have it at his elbow. THE CONSTITUTION OF THE EARTH.f MR. WARD, when a young man of two-and-twenty, favoured the world with a modest essay, in which he enunciated his views on the constitu- tion of the Earth. The leading object of the writer was to show that the Earth had derived its existence from the Sun, and had been, and still was, slowly increasing in size : not by mechanical action, but by a physiological process analogous to the growth of an organic body. Six-and-thirty years have passed since that essay appeared, and science has meanwhile advanced with unex- pected rapidity. Nevertheless Mr. Ward believes that the march of science has only strengthened his position. Soon after the publication of his essay there appeared the Vestiges of Creation , and at a much later period The Origin of Species. But Mr. Ward had forestalled the writers of these works, and had convinced himself of the transmutability of species ; only he had his own way of explaining the operations of the laws of development. The present work is but an expansion of the earlier essay. It is not likely that Mr. Ward will secure a large number of adherents to his peculiar view that the Earth * Demonstrations in Physiological and Pathological Chemist'ry ; with a Concise Account of the Clinical Examination of Urine. By Charles Henry Ralfe, M.A.,M.D. (Cantab.), F.R.C.P.,&c. 8vo. London: David Bogue. 1880. t The Constitution of the Earth ; being an Interpretation of the Laws of God in Nature , by which the Earth and its organic life have been derived from the Sun by a progressive development. By Robert Ward. 8vo. London: George Bell and Sons. 1880. 166 POPULAR SCIENCE REVIEW. is growing larger by a kind of vital action ; nor do we think that be will do much to stem the current of scientific scepticism which has disturbed his peace of mind. The astronomer, not less than the geologist, will have many a bone of contention to fight over with Mr. Ward. STEAM AND THE STEAM-ENGINE* ACCORDING to the title-page of the new edition of Dr. Evers’s Steam, - the work has now reached its twenty-sixth thousand. We may therefore take it that in the keen struggle for existence among the many text- books which crowd the market, Dr. Evers’s work has shown healthy vitality, and has asserted its right to live and to take rank among our standard manuals. At the time of its first appearance there was no work of its kind — at once comprehensive and cheap — and Dr. Evers supplied a want which had been felt, especially by classes working in connexion with the Science and Art Department. Primarily intended for use in such classes, it by no means servilely follows the Syllabus of the Examinations, and certainly stands above a cram-book for use in preparing for the May ordeal. The new edition has been revised, and has received the benefit of an additional chapter on compound engines. EXTINCT BRITISH ANIMALS. f MR. HARTING opens the introduction to his treatise on recently extinguished British Mammals in the following words : — 1 The interest which attaches to the history of extinct British animals can only be equalled by the regret which must be felt by all true naturalists at their disappearance beyond recall from our fauna. It is a curious reflection at the present day, as we pass over some of the wilder parts of the country, that at one time these same moors, and woods, and glens, which we now traverse so securely, were infested to such an extent with ferocious animals, that a journey of any length was, on this account, attended with considerable danger.’ It needs the spirit of the true naturalist to regret the change that has taken place. Either as naturalist or sportsman, however, Mr. Harting revels in the ideas thus conjured up. His imagination brings before him scenes which, to * Steam and the Steam-Engine; Land, Marine, and Locomotive. By Henry Evers, LL.D. {Collins' Advanced Science Series ). 8vo. London: W. Collins and Sons. 1880. t British Animals extinct zvithin Historic Times, with some accounts of British Wild White Cattle. By James Edward Harting. 8vo. London : Triibner & Co., 1880. REVIEWS. 167 ordinary mortals, may seem unattractive enough, hut upon which he dwells with sentimental yearnings. ‘ Packs of wolves,’ he says, ‘ which usually issued forth at night to ravage the herdsman’s flocks, were ever ready to attack the solitary herdsman, or unwary traveller on foot, who might venture to pass within reach of their hiding-places. In the oak woods and amongst the reed-beds which fringed the meres, wild boars lurked Many a traveller then had cause to rue the sudden and unexpected rush of some grand old patriarch of the 11 sownder,” who, with gnashing tusks, charged out upon the invader of his domain, occasionally unhorsing him, and not unfrequently inflicting severe injuries upon his steed.’ Degenerate Britons of the present day may, perhaps, be glad to compound for the absence of such wild beasts as the wolf, the bear, and the wild boar, by their freedom from the chance of finding any such excitements as the above when journeying from town to town on foot or on horseback; but the enthusiasm that prompts the author of this book to express his regret that the wild beasts, with all their inconvenient habits, have passed away from our country, may serve to give the reader an assurance that no pains have been spared by him in its preparation. It is difficult, as he justly says, to realize the state of things above indicated, 1 unless we consider at the same time the aspect and condition of the country in which these animals lived, and the remarkable physical changes which have since taken place.’ Half the country, at least, was forest, or wild, uncultivated ground, and in the disappearance of this state of things the naturalist can hardly avoid finding some cause of regret, hundreds of organisms, both animal and vegetable, must have succumbed to the progress of cultivation and the spread of population, which have now attained such a pitch that one has to travel a considerable distance from London, at any rate, in order to find a bit of undisturbed land. How different from the condition of things some six or seven centuries ago, when the forests came up almost to the gates of London, and the churches in certain cities lighted beacons on their towers to guide belated travellers through the waste outside. Five mammals, which have become extinct in Britain within the historical period, are here recorded by Mr. Harting, namely, the Bear, the Beaver, the Reindeer, the Wild Boar, and the Wolf. On the last-named animal Mr. Harting contributed a long article to this Revieio some years ago. It is treated here very much in the same manner, but with consider- able additional information. The Bear, as a British animal, does not seem to have been abundant in the southern parts of the country within historic times ; but there is no doubt that it existed in England and Wales at least as late as the middle of the eighth century. In Scotland it seems to have survived till the tenth century. Its presence in Ireland as a native animal is doubtful, except from fossil evidence. The Beaver, remains of which are not very uncommon in peaty soils in the fenlands and elsewhere in England, seems to have sur- vived till the end of the twelfth century in Wales, and to a much later period in Scotland. In the latter country there is somewhat doubtful testimony to its occurrence as late as the sixteenth century. The historical evidence of the existence of the Reindeer in Britain is still more scanty, and rests princi- pally upon a statement in an Icelandic Saga to the effect that the Jarls of Orkney were in the habit of crossing to Caithness in the summer to hunt 168 POPULAR SCIENCE REVIEW. this animal and the red deer — a statement the preciseness of which is ren- dered doubtful by the use in the original Saga of a conjunction of variable meaning, which leaves it uncertain whether the writer was referring to two animals, or using what he thought were two names for the same. The Wild Boar seems to have survived until well on in the seventeenth century. Besides these animals, which have become absolutely extinct in this country, Mr. Harting has a chapter on the so-called wild white cattle, generally sup- posed to represent the original wild cattle of these islands ( Bos primigenius). Like the Aurochs or European Bison, these cattle may fairly be regarded as extinct as wild animals, seeing that their only representatives are to be found preserved in certain parks in various parts of the country. The subjects here discussed are of great interest ; and Mr. Harting has spared no labour in endeavouring to do justice to them. Old deeds, books of all k nds, law reports, and the most miscellaneous sources have been ran- sacked by him in search of information upon these former denizens of our islands ; and the result is that he has brought together, in a most readable form, a mass of very curious information, old and recent, of special interest to the zoologist, but which may be perused with pleasure even by those who are not naturalists. THE CHRISTIAN KNOWLEDGE SOCIETY. THE Committee of the Society for Promoting Christian Knowledge seem inclined to hold very broad views as to what may be called i Christian Knowledge.’ Their theory, no doubt, is that the cultivated Christian ought not to be behind other people in general knowledge, and in this we think they are quite right. We have already had occasion to notice one or two popular works on scientific subjects : such as Prof. Duncan’s little sea- side book, and the late Prof. Ansted’s elementary treatise on Minerals ; and we have now received from the Society a parcel of books, to which we may call the reader’s attention, although some of them have no claim to a strictly scientific character. This applies more especially to two volumes by Mr. Davenport Adams, entitled Wrecked Lives, or Men who have failed, in which the author has given some account of the lives of several more or less prominent or dis- tinguished men, who, like the boy who didn’t care, came to a bad or unsatis- factory end. Another work, by the same author, describes the doings of a select band of travellers, commencing with Marco Polo, and winding up with Major Burnaby and Sir Samuel Baker. This little book* will be read with interest ; it gives a good popular account of some of the more important journeys made in various parts of the world. Mr. Eden’s volume on Africaf * Some Heroes of Travel ; or Chapters from the History of Geographical Discovery and Enterprise. By W. H. Davenport Adams. Sm. 8vo. London, 1880. t Africa, seen through its Explorers. By C. H. Eden. Sm. 8vo. London. REVIEWS. 169 gives a good popular history of the progress of discovery on the African continent, embracing the labours of Bruce, Park, and his successors Denham, Clapperton, and Lander, Du Chaillu and Schweinfurth, and finally Living- stone. The book concludes with Livingstone’s last expedition. It is illus- trated with a small folding map of Africa and some tolerably good wood- cuts. Two other little volumes, although not upon what are generally con- sidered scientific matters, may nevertheless possess considerable interest for the readers of this Review. They are treatises upon the two great ancient systems of philosophy, — Stoicism and Epicureanism.* Both these little books appear to be exceedingly well executed, and the subjects are handled in a free and philosophical spirit. We may remark, especially in connexion with these works, where it might have been looked for, the entire absence of any obtru- sive Christian pietism. The authors seem throughout to seek to recognize what is good in these ancient philosophies, and to lay before their readers a candid statement of the historical facts. In Dr. Goodwin’s treatise on the Origin of the World according to Reve- lation and Science ,f we certainly seem to see some traces here and there of the odium theologicum, and we do not think the author has done very much towards clearing up the difficulties of the case. He evidently does not clearly realize what is meant by origin of species by evolution. The key to his idea is that the account of the creation in Genesis is to some extent poetical, but especially moral and didactic, the description of the creation of animals and plants being merely the framework for the picture of the creation of man to which they in a manner lead up. The first of a series of shilling Manuals of Elementary Science% is on Electricity, and by Prof. Fleeming Jenkin. It is necessarily a very brief exposition of the principles of the science ; but it seems to be very clearly written, and to touch upon all the more important points. We have kept to the last the most pretentious of the volumes that we have received from the Society ; not, however, for the ordinary reason that it is the best, but from directly opposite considerations. It is called a Natural History of British Fishes, by the late Frank Buckland,|| and but for the melancholy circumstances under which it has been produced, we should have felt bound to handle it pretty severely. As a Natural History of British Fishes it is lamentably defective, the author’s well-known want of scientific knowledge, and ignorance or disregard of what other people have done, being conspicuously shown in nearly every page ; and the book may be defined as little more than a pretty lively narrative of Mr. Frank Buckland’s experi- ences in the pursuit of ichthyological knowledge by the light of his own * Stoicism. By the Rev. W. W. Capes. — Epicureanism. By William Wallace. Sm. 8vo. London, 1880. + The Origin of the World according to Revelation and Science. A Lecture by Harvey Goodwin, D.D. Sm. 8vo. London, 1880. t Electricity, By Fleeming Jenkin. Sm. 8vo. London, 1880. || Natural History of British Fishes ; their Structure , Economic Uses, and Capture by Net and Rod. Cultivation of Fish Ponds. Fish suited for Acclimatisation. Artificial Breeding of Salmon. By Frank Buckland. Svo. London, 1881. 170 POPULAR SCIENCE REVIEW. intellectual lanthorn. It contains, however, some interesting details upon fisheries ; and the practical appendix on fishponds, the acclimatization of fish, and the art ificial breeding of salmon, may prove useful. The account of the salmon is also the best section in the body of the work. The woodcuts with which it is illustrated are for the most part indifferent. PLANT LIFE.* WE do not know why the author of this little work has thought proper to publish it anonymously. He has certainly no occasion to conceal his name, for the series of chapters on Botanical subjects, which he has here brought together, show a sound knowledge of the science, and very considerable power of communicating that knowledge in a pleasing and in- teresting manner. The book does not profess to be a systematic treatise on Botany, but a good method runs through the seemingly desultory chapters ; and the general facts of the history of plants will be found to be well described in them. The author commences with microscopic plants, and then describes the structure and growth of plants, and the mode of fertiliz- ation of flowers. Ferns occupy another chapter, and others are devoted to the lower groups of Cryptogamia. Becent researches are referred to, such as those of Mr. Darwin and others on predatory plants, on the fertilization of Orchids, and on polymorphism. Interspersed with these are good chapters on the folk-lore of plants, on plants and animals, and on plants and planets, the latter an exceedingly amusing and well-written exposition of some of the absurdities of the old astrological herbalists. On the whole we have seldom seen a book better adapted to inspire unscientific readers with taste for the study of a science. With the view probably of assisting those who may be induced by his more popular book to commence botanical investigations, the same author has published some Easy Lessons in Botany, f which seem ex- ceedingly well fitted for the above purpose. What ‘ the requirements of the Revised Code, 1880,’ may be we don’t know ; but the little book is said to be written to fulfil them. Both these books are nicely illustrated with nume- rous woodcut figures drawn by the author. MOVEMENTS OF PLANTS 4 MR. DARWIN in this work investigates and discusses, after his usual thoroughgoing fashion, a series of phenomena of movement displayed * Plant-life : Popular Papers on the Phenomena of Botany. With 148 illustrations drawn by the author. Sm. 8vo. London : Marshall Japp & Co. 1881. f Easy Lessons in Botany. By the author of Plant Life. Sm. 8vo. London : Marshall Japp & Co. 1881. . X The Power of Movement in Plants. — By Charles Darwin, LL.D., F.R.S. Assisted by Francis Darwin. 8vo. London: John Murray, 1880. REVIEW. 171 by plants, to which he gives the general name of ( circumnutation.’ This term is employed to express the tendency of the different parts of plants in growth, to describe a series of irregular curves, loops, and zig-zags, by their movements successively towards all points of the compass. As we propose in the next number to have an article explanatory of Mr. Darwin’s views, we shall not attempt to discuss them in the space at our disposal here, The experiments recorded are of the most ingenious kind, and carried out with the utmost care, and with that attention to all minutiae which Mr. Darwin so well knows how to bestow upon the most complicated investiga- tions. Hundreds of figures, showing the tracks made by growing plumules and radicles, are reproduced in woodcuts, and we think that on inspecting them the reader will be rather surprised to find that Mr. Darwin has been able to evolve anything definite from such an apparent chaos. 172 SCIENTIFIC SUMMARY. i ANTHROPOLOGY. Quaternary Human Remains at Nice. — On the 21st March some reports upon the occurrence of human remains in an undisturbed deposit at Nice were laid before the French Academy (see Comptes Rendus of the above date), j M. Desor described the geological structure of the ground, which had at the surface metre of vegetable soil, followed by P93 M. of tufaceous calcareous mud, overlying about 1 metre of siliceous sand, with intermixed Pliocene and Eocene fossils, beneath which were 2 metres of gravel, more or less conglomerated, surmounting a compact conglomerate. The bones were found in the calcareous deposit at an altitude of from 25 to 30 metres above the bottom of the surrounding valleys. There is no trace of disturbance or irregularity around the cavity from which the remains were extracted, and i all the characters of the deposit show that there can be no question of j inhumation. The portions of skeleton obtained were found 058 M. above the bottom of the deposit. The stratification is in all directions, and would seem to indicate torrential action, so common in quaternary times; the J human skeleton was probably conveyed to the position where it was found by a current. The deposit must have been formed at a period when the shore was lower than at present, when the Paillon and the other water- courses of the coast spread over the Tertiary plateaux before they had j hollowed out their present beds. The deposit is thus one of the diluvial formations contemporaneous with the erosion of the Tertiary plateaux. The human remains found, as determined by Dr. Niepce, consist of the following bones : — Part of the lower jaw, including the left and part of the right ramus, and containing the four last molars well preserved. The alveoli I of the teeth are vertical, with no trace of prognathism. The left ramus | measures 11 centim. from the angle to the symphysis ; and the distance between the two branches is 95 millim. The teeth are scarcely at all worn, and the j last molar is as large as the rest. The other bones are a fragment of the middle of the femur, fragments of the left tibia, a fragment of the left humerus, a fragment of the radius, and a fragment probably of the clavicle. From the examination of these portions Dr. Niepce arrives at the conclusion that the bones probably belonged to a j small person not less than thirty years old, probably a woman. M. de Quatrefages goes into the question of race, for the determination of j which the materials do not seem very sufficient. He finds, however, that j SCIENTIFIC SUMMARY. 173 the jaw strikingly resembles that found in the caves of Engihoul near Liege in I860, which, from additional evidence was referred by M. Hamy to the race of Cro-Magnon, and this identification would lead to the Nice jaw being referred to the same race, along with the skeletons obtained by M. Riviere near Mentone. M. de Quatrefages finds this identification supported by two fragments of bone which he refers to the right femur, and which strikingly present the strong longitudinal projection ( tinea aspera) which is characteristic of the men of Cro-Magnon. This race consequently lived in the Quaternary period both on the shores of Nice and among the mountains of Perigord. ASTRONOMY. The real Lihration of the Moon. — It has long been suspected that from its slightly ellipsoidal figure, the Moon undergoes a real libration, or slight periodical inequality, in its otherwise uniform rotation on its axis. Several attempts have been made to determine the amount of this real libration, but without any great success, though it is known that it must follow certain well-ascertained theoretical laws. Indeed, the theory of gravitation enables us to calculate the theory of this real libration with all desired accuracy, it only remains for observation to determine what is its actual maximum amount ; for this depending on the actual figure of the Moon is outside the domain of theory, and appertains strictly to observation. Lately, Herr Dr. Hartwig, of the Strassburg Observatory, has made an important addition to our knowledge of this subject by an elaborate memoir entitled, Beitrag zur Bestimmung der Physischen Libration des Mondes. He has employed, as the foundation of his investigation, forty-two measures, by means of the Strassburg heliometer, of the distance of the crater Mosting A, from seven points in the limb of the Moon. These measures Herr Hartwig proceeds to reduce in practically the same manner as employed by Herr Wichmann in his famous investigation of the year 1847, using exactly the same theoretical basis. The main results obtained by Herr Hartwig, and those previously obtained by Herr Wichmann, are appended : — Wichmann. Hartwig. Latitude of Mosting A . . = — 3 10 21 ± 11 = — 3 10 55 ± 24 Longitude of Mosting A . = - 5 10 57 ± 25 = - 5 13 23 ± 89 Inclination of the lunar equa- tor to the ecliptic . . = 1 36 34 ± 113 = 1 39 9 ± 250 So far the results are not very discordant, and the small probable errors indicate the superior trustworthiness of Herr Hartwig’s results. The effects for the real libration may be written as follows : — Real libration in latitude . = + 17 sin { 13*188 T + 80° } according to Wich- mann. = + 295 sin { 13*188 T + 80 } according to Hart- wig. 174 POPULAR SCIENCE REVIEW. Eeal libration in longitude = + 178 sin { 0-480 T } + 150 sin [i - 24" sin a, according to Wich- mann. + 61 sin { 0-396 T + 90°} + 124 sin fi - 21" sin a, according to Hart- wig.* It will be seen that these results are very far from being as accordant as they ought to be, and show that there have been grave systematic errors in one, or both, of the two series of observations or reductions. It is much to be desired that a reduction should be made of a great number of observa- tions made by Herr Schliiter in 1841-44, and it would be desirable to have Herr Hartwig’s results reduced with values for the arguments derived from his own observations, and not from those of Wichmann. Prof. Pritchard, of the Oxford Observatory, is also reducing a number of j measures of photographs of the Moon, with the view of determining the real libration. His results are not yet published, but he has stated that j they are in accord with those found by Wichmann. In a recent communi- cation to the Koyal Astronomical Society, Prof. Pritchard speaks rather despondently of the prospects of determining the actual amount of this real libration. Quoting from an account of his remarks at the Society ( Observatory , February 1881), he says : ‘We must accept this — that these measures and these calculations, though beyond all doubt they show that j there really is a lunar physical libration, and that it is somewhere between these numbers, yet you will never get it within 20 or 30 or 40 seconds.’ But there are far superior methods for determining this real libration than have ever been employed as yet ; and so far from accepting the gloomy view taken by Prof. Pritchard, it is probable that astronomers will look to one of these improved methods to reduce the uncertainty to far smaller limit than supposed by Prof. Pritchard. It may be here mentioned that 20 to 40 seconds of selenographical longitude corresponds at the mean j distance of the Moon to only one to two tenths of a second of arc ; a small enough quantity. The Diameter of Mars. — Lately {Monthly Notices R.A.S. Nov. 1880) Mr. Downing has determined, from some five hundred measures with the Greenwich Transit Circle, the mean diameter of the planet Mars, which he finds to be — = 9"-697 ± 0"-107 He also finds that there is a constant correction required for irradiation, j which is equal to — = + 2"-369 ± 0"-175 As Mr. Downing points out, the correction is unusually large, that for the Washington 4-inch Mural Circle being only 1"T92. Mr. Stone, F.R.S., has also lately made a communication to the Astro- nomical Society on the same subject. He finds that different observers have a considerable personality in observing the diameter of the planets, some ] * In these formulae, T = the number of mean solar days for January 1, 1845; y denotes the mean anomaly of the Sun; and a, the mean anomaly of the Moon. SCIENTIFIC SUMMARY. 175 making it systematically larger than others. Thus Mr. Ellis’s personal equa- tion amounted to + 1"T0, whereas Mr. Dunkin’s was - 0"’68, so that Mr. Ellis systematically makes the diameter of Mars 1 "’78 larger than Mr. Dunkin. A further result was also ascertained, namely, that the diameter was systemati- cally made too large when the planet is at a considerable distance from the Earth. Lastly, Mr. Stone considers that the large irradiation constant obtained by Mr. Downing is fictitious to a certain extent, and due to other causes. 1 The Diameter of Vesta. — Last year, from a numerous set of measures, Prof. Tacchini of Rome determined the apparent diameter of this minor planet to be — = l"-706 ± 0"-09. Since then another set of measures has been obtained by his colleague, Prof. Millosevich, who finds the diameter to be — = 1 "-655 ± 0"-09. These results, freed from the effect of irradiation, would give about 800 miles for the diameter of this planet. Jupiter. — Further interesting observations have been made by different observers of the changes which are taking place in the cloud strata of this giant planet. The white spots on the equatorial belt continue to remain visible, but are becoming more irregular in form and dimensions ; their edges, too, are becoming softer and less sharply defined. They continue to move much faster than the great red spot, which still continues visible, but has lost much of the vividness of its tint ; and Mr. Denning has watched one gain a whole revolution of the planet on the red spot. The band of dark irregular spots on the northern equatorial belt continued to be visible during the winter, but they have changed very considerably in form and appearance, rendering it difficult to accurately determine the period of their rotation. They seem now to move faster than the white spots, though originally Schmidt and some other observers considered their motion to be slower. The greyish belt north of this belt of blackish spots has grown thicker and darker of late, and still further north there are signs of a new belt. Mr. W. F. Denning thus sums up the results of his winter observations ( Observatory , March 1881) : ‘ It is to be noted that the recent observations of this planet have re- vealed, in the clearest manner possible, a quadruple series of spot-motions. There is the red spot with its period of 9h 55m 34s ; the short, dusky streaks (south on the red spot in the southern hemisphere) with their approximate line of 9h 55 jm, the bright spots on the equator with 9h 50 jm, and the dark, irregular spots ranged along the belt north of the equator with 9h 48m. Further observations may reveal other phenomena of equal importance ; and it is certain that the time has come when this planet will be subject to the constant and critical examination which the marvellous variations in his appearance so obviously demand.’ M. Bredichin is of the opinion that all the recent phenomena presented by the planet Jupiter can be explained by supposing that there is an elevated equatorial belt to the planet, and that there is more heat radiated from the southern hemisphere of the planet than from the northern. Lately an interesting investigation has been published by Herr Harzer, giving the results of his investigation of the perturbing action of this giant planet, Jupiter , on the motion of Brorsen’s comet of 1846, on the occasion of the very close approach of the comet to Jupiter in May 1842. Herr Harzer 176 POPULAR SCIENCE REVIEW. lias ably calculated the great changes in the orbit of the comet produced by the attraction of this giant planet, the principal being a change in the mean anomaly of nearly two degrees in the vectorial angle or eccentricity of a degree, and in the inclination of about two degrees. He also calculates the form of the orbit in which the comet must have moved prior to its close approach to Jupiter, and shows that the elements resemble those of a comet discovered by Messier in 1798. He does not think it likely, however, that the two comets are the same. Herr Harzer thinks that there is reason to believe that the orbit of the comet would have suffered similar great changes in 1760, and may undergo similar changes in its near approach in 1937. On November 20, 1880, Mr. J. Birmingham observed the star B D + 2°, 97 quite close to the planet Jupiter, being distant only by 4"*05, and giving to the planet all the appearance of having five satellites. The light of the star was, however, very different from that of the satellites; and, though it is a 7 ‘7th magnitude star, it shone only like a 10th magnitude star, owing to its proximity to the bright planet. Swift's Comet = Comet e, 1880. — The later observations which have been made of this comet have seemed to materially alter the earlier impression about its orbit. Instead of having a period of eleven years, it seems that there can be no doubt that its period is really only half of this, or about five and a half years ; but owing to the position of its orbit the comet is invisible at every other return to perihelion. The latest and best orbit seems to be that by Mr. Winslow Upton of Washing-ton. He finds as follows : — Epoch 1880, Oct. 25*5, Washington mean time. r M = 357 48 49 '3 = Mean Anomaly at Epoch. 1880 J a = ^96 41 55-4 = Longitude of Ascending Node. J W = 106 18 13*8 = Distance of perihelion for Ascending Node. \ i — 5 31 3*5 = Inclination of orbit. e = 0*67594 = Eccentricity. a = 3*29942 = Semi-major axis, ju = 592"*0373 = Mean Motion. From these figures we learn that the comet passed through its perihelion on November 7*79433 Washington mean time, and has a period of 2189*1 days, or only 2*4 days short of six years. This result is in close accord with that calculated by Prof. Frisby from less perfect data. The period of this comet is so nearly equal to half that of the planet Jupiter, and its orbit approaches so close to that planet, at a time when that planet is not far dis- tant, that the comet must undergo considerable perturbation in its motion. Pechule's Comet = Comet f, 1880. — On Dec. 16, 1880, Herr Pechiile dis- covered a comet not far from the place of Hartwig’s comet. It was small, and at the time of its discovery pretty bright. It soon grew faint, however. According to Prof. Young this comet had two tails, the upper and brighter one was directed towards the Sun, and about 40' in length ; the other, or fainter, tail was only about two-thirds as long. They were too faint to be seen after the 22nd. From the observations Mr. C. S. Chandler has computed an orbit. The elements he obtained were : — SCIENTIFIC SUMMARY. 177 T = 1880, Nov. 9*4087, Washington Mean Time. \ == 263 0 13 Longitude of Perihelion. & = 249 38 44 Longitude of Ascending Node. i = 60 41 24 Inclination, log q = 9*830884 Log of Perihelion distance. Motion direct. Mr. Chandler remarks, 1 The orbit of this comet presents a curious general resemblance to that of 1807, memorable from the elaborate investi- gation by Bessel, whose results indicated a period of 1483 years, and could not be reasonably satisfied with a period of less than 700 years.’ A New Suspected Extension of the Milky Way. — An interesting account has been published by Mr. Arthur Searle, one of the assistant astronomers at the Harvard College Observatory, U.S. : — * During the last five years I have become convinced by repeated observa- tions that a very faint, but permanent band of light extends from Aquila to the Pleiades, passing through Aquarius and the southern part of Pisces. Since a considerable part of its course lies near the ecliptic, it may interfere to an appreciable extent with observation of the Zodiacal Light, and may be worth mentioning on this account. ... I have consulted several works likely to contain information on similar subjects without finding any notice of it, and its presence seems not to have been generally recognized, if at all. Other observers here have seen parts of it favourably situated for observation at the time when pointed out to them ; but fuller and more independent observations are of course required to furnish satisfactory evidence of its existence. As I see it, its width is about 5°, and a line drawn along the middle of the band will begin between a and S Aquilce, and pass between a and /3 Aquarii, nearly through % Aquarii ; thence crossing the ecliptic it will pass near 27 Piscium and v Piscium, and will end after recrossing the ecliptic in the faint extension of the Milky Way towards the Pleiades. The colour of this luminous band seems to me whitish, not yellowish like the brighter parts of the Zodiacal Light. ... If other observers should concur in my opinions with regard to the existence and course of this luminous band, it will be a question of some interest whether telescopic stars are unusually abundant along it. This would of course afford the simplest explanation of any phenomenon of the kind.’ — Ast. Nach., No. 2358. Parallax of a and ft Centauri. — Herr C. W. Moesta has lately carefully reduced the great number of observations of these stars made at Santiago, in Chili, during the years 1860-1864. From his results he deduces a parallax for a2 Centauri of + 0"*579, and for (3 Centauri of 0"*2096, the difference or relative parallax of the stars being 0"*369, which is somewhat less than that found from the observations made at the Cape. Parallax of the Star Piazzi III. 242. — Nearly twenty years ago attention was directed by Otto Struve to the desirability of determining the parallax of this star as it forms a wide binary pair with its neighbour, 50 Pjrsei, some 15' distant, and is itself a binary double. Dr. Ball has lately taken up this investigation, but with disappointing results, as the parallax comes out with a very small negative quantity. It is obvious, therefore, that this star has no sensible parallax. It would really seem worth ascertaining whether its binary neighbour, 50 Persei, also gave a similar result. NEW SERIES, VOL. V. NO. XVIII. N 178 POPULAR SCIENCE REVIEW. BOTANY. The Markings of Diatoms. — M. W. Pring has sent us a copy of a paper communicated by him to the Societe Beige de Microseopie {Mem. tome vii.), containing descriptions of some sections of Diatoms. He obtained his sec- tions by mating thin slices of a diatomaceous rock from Nykjobing, in Jutland, and his observations relate chiefly to three species, namely, Coscino- discus ocvdus-iridis , C. excentricus , and Trinacna regina. In the first and third of these he finds that the markings of the valves are true alveoli tra- versing the thickness of the outer layer, and terminating against the inner layer, which is also perforated by smaller apertures. Diongated Spiral Cells in the Leaves of Crinum. — M. Trecul finds that in the leaves of some forms of Crinum , especially C. americanum, there are large spiral cells with the aspect of spiral vessels, either isolated in the parenchyma, or collected into more or less numerous groups. The blade of the leaf shows numerous parallel fibrovascular bundles, which become thicker in the direction of the thickness of the leaf towards the middle of the blade ; between them are vacant spaces formed by the destruction of the parenchyma, but interrupted by transverse dissepiments of parenchyma uniting the neigh- bouring bundles. The spiral or tracheiform cells described by M. Trecul, occur in all parts of the parenchyma of the leaf, but nowhere else in the plant. They attain a considerable length, but in this respect vary greatly. M. Trecul indicates a range of length of from 0*50 to 13-40 millim., in the same species. Two of them were observed to be forked. The number of spiral cells is much greater in Crinum americanum than in C. taitense ; in fact, these two species may be distinguished by the characters furnished by these cells. C. africanum comes nearer to the American species. M. Tre- cul suggests the question whether the plants presenting the above-mentioned anatomical character, which is not shown by the other Crina , are to be regarded as having the same specific origin. If they had a common origin they have undergone considerable modifications ; the Tahitian plant, espe- cially, differing very widely from the American. On the other hand, C. taitense being identified by Herbert and Kunth with Rob. Brown’s C. pedunculatum , which they regard as the first variety of C. australe, and therefore allied to C. nibricaule, exaltatum, and canaliculatum, the three other varieties of C. australe , it would be interesting to ascertain if all these forms possess the same character of the presence of spiral cells in the parenchyma of the leaves. — Comptes Rendus , 4 February and 7 March , 1881. GEOLOGY AND PALAEONTOLOGY. South African Triassic Reptiles. — In a paper read before the Geological Society in April last, and since published in the Quarterly Journal of the Society (Yol. xxxvi. p. 414), Prof. Owen described the remains of a reptile of his order Anomodontia, from the trias of Graaf Reinet, in South Africa, which he considered to show strong resemblances to the lower forms of the Mammalia. The fossils consisted of some thoracic vertebrae, with portions SCIENTIFIC SUMMARY. 179' of ribs, a sternal bone, a scapula, and a right humerus, found imbedded in one mass of rock, and of a femur and phalanges, and a pelvis in another mass. With the exception of the pelvis, Prof. Owen described these bones in detail. The vertebrae agree most nearly with those of Dicynodon , and Oudenodon. The supposed sternal bone is of a rounded hexagonal form, and is regarded by Prof. Owen as the anterior bone of the sternum proper, which is usually unossified in recent lizards, but well ossified in Ornithorhynchus. The scapula also presents resemblances to that bone in Ornithorhynchus. The humerus in its general proportions, and especially in the great develop- ment of its ridges, was also shown to> resemble the same bone in the Mono- tremes. The ungual phalanges were described as broad and obtuse, probably constructed to bear claws adapted' for- digging, as in Echidna; the femur also resembles that of the last-named animal. Prof. Owen remarked upon these approximations to the Monotrematous Mammalia, in allusion to which he proposed the name of Platypodosaurus robustm for this animal, the humerus of which was 10| inches long and nearly 6 inches broad at the distal end. He also alluded to the interesting problems- opened up by the study of these South- African reptiles in connexion with their possible relationships to the low implacental’ Mammalia of New Guinea, Australia, and Tasmania. Subsequently the pelvis was freed from-, the -matrix, and Prof. Owen com- municated a description of this part of the skeleton to the Geological Society (9th March, 1881). The fossil includes the sacrum, the right ‘ os innominatum/ and a great part of the left ilium. There are five sacral ver- tebrae) which Prof. Owen believes to be the total number in Platypodosaurus. The neural canal of the last lumbar vertebra is eight lines in diameter, and of the first sacral nine lines, diminishing to six lines in the fifth, and indi- cating an expansion of the myelon in the sacral region, which is in accordance with the great development of the hind limbs. The sacral vertebrae in- crease in width to the third; the fourth has the widest centrum. The coalescence of the vertebrae justifies the consideration of the mass, as in Mammalia, as one bone or 1 sacrum/ which may be regarded as approaching in shape that of the Megatherioid Mammals, although including fewer ver- tebrae. Its length is 7\ inches ; its greatest breadth, at the third vertebra, inches. The ilium forms the anterior and dorsal wall's- of the acetabulum, the posterior and postero-ventral walls of which are formed by the ischium and pubis. The diameter of its outlet is 3 inches,, the depth of the cavity 1| inch, and at its bottom is a fossa inch broad.. The foramen is sub- circular, 1 inch in diameter. The ventral wall of the pelvic outlet is chiefly formed by the pubis,; it is a plate of bone 6 inches broad,, concave externally, convex towards the pelvic cavity. The subacetabular border is 7-8 lines thick ; it shows no indication of a pectineal process, or of a prominence for the support of a marsupial bone. Prof. Owen remarks that of all examples of pelvic structure in extinct Reptilia this departs furthest from any modi- fication known in existing types, and makes the nearest approach to the Mammalian pelvis. This is shown especially by the number of sacral ver- tebrae and their breadth, by the breadth of the iliac bones, and by the extent of confluence of the expanded ischia and pubes. At the same meeting Prof. Owen described another new South African 180 POPULAR SCIENCE REVIEW. reptile from the Trias of Gough, in the Karoo District of South Africa, which he also considered to show strong tendencies towards the Mammalia ; hut this species he refers to the Theriodont Reptiles, and hence its approximation to the Mammalia would seem to lead in the direction of the Carnivorous Marsupials. This new type, described by Prof. Owen under the name of JElurosaurus felinus, is represented by the skull with the lower jaw, but with the post- orbital part broken away. There is a single nasal opening (mononarial) ; the alveolar border of the upper jaw is slightly sinuous, concave above the in- cisors, convex above the canines and molars, and then straight to beneath the orbits. The alveolar border of the mandible is concealed by the over- lapping teeth of the upper jaw ; its symphysis is deep, slanting backward, and destitute of any trace of suture ; the length of the mandible is inches, which was probably the length of the skull. The incisors are - — -, and the g 5 g g ® 5 molars probably — - or all more or less laniariform. The length of the exserted crown of the upper canine is 12 millims. ; the root of the left upper canine was found to be twice this length, extending upwards and backwards, slightly expanded, and then a little narrowed to the open end of the pulp- cavity. There is no trace of a successional canine ; but the condition of the pulp-cavity and petrified pulp would seem to indicate renewal of the working- part of the canine by continuous growth. The author infers that the animal was monophyodont. JElurosaurus was said to be most nearly allied to Lyco- saurus, but its incisor formula is Dasyurine. With regard to the characters of the Theriodontia, the author remarked that we may now add to those given in his 1 Catalogue of South African fossil Reptiles,’ that the humerus is perforated by an entepicondylar foramen and the dentition monophyodont. Some of the opinions expressed by Prof. Owen with regard to these Reptiles, especially as to their Mammalian tendency, and the distinctive characters of the order Theriodontia, met with some objections from Mr. Hulke and Prof. Seeley, but the facts adduced are certainly of much interest. Batrachians and Reptiles. — Prof. Cope has some remarks ( Amer . Nat., August, 1880) upon his genus Cricotus, founded upon specimens obtained from a shale of Triassic or Permian age in Illinois, and distinguished from the rest of the Stegocephali (Labyrinthodonts) by the complete develop- ment of the centra and intercentra of the vertebrae, both of which form vertebral bodies, and, in pairs, support single neural arches. No such cha- racter has been detected in the recognized divisions of the Stegocephali ; and further knowledge of the structure of the genus shows that it is the type of a distinct division of that group, which Prof. Cope defines as follows : — 1 Centra and intercentra subequally developed as vertebral bodies, a single neural arch supported by one of each, forming a double body. Chevron bones supported only by intercentra. Basioccipital vertebral articulation cuplike, con- nected with the first vertebra by an undivided discoid intercentrum.’ Thus the peculiarity of the vertebral column in general is continued into the articu- lation of the head ; and, instead of the complex atlas of the Ganocephali, there is a single body connecting occipital condyle and first vertebra. In all SCIENTIFIC SUMMARY. 181 probability, this single body represents the single occipital condyle of the Reptilian skull , a part which remains cartilaginous in the Lizard long after the basioccipital is ossified, and is a distinct element. The structure of Cricotus shows that it is a connate intercentrum. Prof. Cope says : — ( We have now removed the last difficulty in the way of the proposition that the Reptilia are derivations of the Batrachia, viz., the difference in the cranio-vertebral articulation. But the former have not been derived from the Labyrinthodontia, as has been suggested, nor from the Ganocephala, but from the Embolomera, as I call the new order or sub-order. The order of Reptiles, which stands next to it, is, of course, the Theromorpha, which pre- sents so many Batrachian characters, including intercentra.’ The genus Diplovertobron , described by Fritsch from the Permian gas-coal of Bohemia, is believed by Cope to belong to the same group as Cricotus. Geology of the Cape Verde Islands. — Dr. C. Dolter gives a general account of the geology of the Cape Verde Islands in a letter to Prof. Von Hauer ( Verhandl. k. k. geol. Reichsanst. 15 February, 1881). He says the group of of islands, consisting of two separate clusters, is of volcanic origin ; but in places there are also sedimentary rocks, especially limestone, as on the islands of Mayo and Bravao, which, with Santiago and the still active volcano Fogo, form the southern cluster. The unfossiliferous, dense, reddish limestones of Mayo, greatly remind one of the marbles of Trent. It would be difficult to determine their age, and for this purpose a study of the formations on the African continent would be necessary. The island of Santiago, the largest of the Archipelago, represents the remains of a very large volcano, of which the crater is still partially preserved in the Pico d’ Antonio, a peak of 2450 metres in height. The great crater of the Pico d’Antonio has formed the whole island, and furnished an enormous number of lava - streams, separated by strata of tuff and rapilli. Veins are rare, and of subordinate importance. In the vicinity of the centre of eruption tuffs and breccias pre- dominate. Besides this great volcano, there are on the margins a dozen of smaller, secondary ones, from 200 to 400 metres in height. The products of the volcano are rocks which maybe characterized as andesites, olivine-basalts, and phonoliths, although, of course, their precise composition can only be ascertained by careful examination. As inclusions in the volcanic rocks, there are lumps of limestone converted into marble, and containing materials like serpentime and chlorite, and also phyllite, mica-schist, diorite, diabase, &c. The marbles are the most interesting of these, as such contact formations have hitherto rarely been observed in recent volcanoes. Of the northern group Dr. Dolter has only examined the volcano of San Vicenti, a great volcano the former crater of which forms the harbour of the island. It consists chiefly of lava-streams, which fall towards the sea uniformly at a gentle inclination. Between them are masses of tuff of sub- ordinate importance, with numerous veins. The margin of the crater has an elevation of about 1200 metres. In the midst of the crater Dr. Dolter found, to his great surprise, masses of dioritic and diabase-like rocks from two to three kilometres in length and breadth, some of them resembling hypersthe- nite; they were penetrated by veins of basalt and andesite, the rocks forming the volcano, and overtopped by lava-streams. Dr. Dolter thinks it probable that in these we have masses of the ancient continent, the existence 182 POPULAR SCIENCE REVIEW. of which seems to he proved by the occurrence of masses of schist in the limestone. Ancient Eruptive Rocks of the Ruy-de-Dome. — M. A. Julien has communi- cated to the French Academy ( Comptes Rendus 28th March, 1881) some observations on the ancient eruptive rocks of the great plateau which bears the more modern volcanic formations of the Puy-de-Dome. His statement will probably be interesting to travellers in the Auvergne who pay atten- tion to geology. The rocks found are as follows : — Porphyroid granite, ordinary granite with grains of moderate size, leptynite (granulite of M. L6vy), pegmatite with tourmaline and garnets, amphibolic rocks, diorite, amphibolite, and amphibolic petrosilex. The porphyroid granite forms vast expansions, but all the other rocks are in the form of veins, which are very numerous and distinctly marked. The veins of leptynite and pegmatite have a general north and south direction, with slight deviations to the east and west. The veins of amphibolic rocks, on the contrary, generally run W.N.W. The order of appearance of these rocks was as follows: — First came outflows of porphyroid granite, which is the most ancient granite of the region ; then granite with modemte-sized grains in strong veins in the porphyroid granite ; then the veins of diorite. During the emission of the latter, amphibolic granites were injected between Aydat and Phialeix, and these again were traversed by veins of rose-coloured and green amphi- bolic petrosilex. Innumerable veins of leptynite afterwards appeared, and the pegmatites concluded the series of eruptive phenomena. The last two rocks are always quite distinct. The author states that all these relations are recognizable with the greatest clearness in many parts of this magnificent plateau; but he indicates certain points which he thinks of the most interest. 1. At the Cotes de Ceyrat, along the road which ascends the flanks of the granite cliff to Berzet, the porphyroid granite contains enormous blocks of Cambrian schists. Very distinct veins of ordinary granite, some of them several metres thick, traverse the porphyroid granite. One of them in its course traverses one of the enclosed blocks. Veins of leptynite traverse both granites, and one of them also cuts through the same block of schist already traversed by the ordinary granite. 2. In the quadrilateral included between Theddes, Chadrat, Saint-Genes, Champanelle, and Berzet, the porphyroid granite encloses hundreds of "Cambrian fragments, into which it is also injected in branching and anasto- mosing threads and veins penetrating the fissures of the blocks. The granite rmust therefore have been extremely fluid at the time of its production. 'There is no trace of metamorphism ; innumerable N. and S. veins of leptynite and pegmatite traverse the whole system. 3. Near Recolene, at 100 metres in front of the village, a magnificent wein of diorite enclosed in Cambrian quartzite, is distinctly cut through by a vein of leptynite 20 centimetres thick. 4. Between Santeyras and Aydat, on the margin of the lake, there is on the road, 100 metres from Santeyras, a thick vein of diorite running N. 50° W. traversing the porphyroid granite and a large included mass of schist. This is in its turn cut by a vein of tourmaliniferous pegmatite 20 centi- metres in thickness. SCIENTIFIC SUMMARY. 183 5. Near the last house in the village of Theddes a vein of leptynite, 80 centimetres thick, is cut nearly at right angles by a vein of pegmatite with tourmaline of about equal size. The formation of all these rocks is considered by the author to have, taken place during the Silurian epoch. PHYSICS. A Note on the Determination of the Magnetic Inclination in the Azores is communicated to the Proceedings of the Royal Society by Dr. Thorpe. He notes that except a series of similar observations made by the officers of the Challenger in 1873, none have been made since Captain Vidal’s survey in 1843. Magnetic observing is difficult in these islands, from the intensely vol- canic nature of the strata. The dip-circle used was lent from Owens College, Manchester. In the island of St. Michael the mean dip was 62° 4CP2 N., against 63° 56'*8 N. of the Challenger. In Terceira it was 64° 10r,3, and in Faya! 63° 38'*5. The Thermo-electric behaviour of Aqueous Solutions, with Platinum Electrodes, has been further studied by Dr. Gore, in continuation of his memoir, already abstracted in this Summary. To prevent suspicion of error from chemical action upon the mercury electrodes therein used, coiled ribbons of sheet platinum were substituted for mercury, all other parts of the apparatus remaining exactly similar to those employed in the former experiments. They were heated to redness and thoroughly washed. Pre- cisely similar liquids were used as in the first researches, none of them acting chemically on platinum. These were boiled for half-an-hour to expel dis- solved air. At 180° Fahr. cyanide of potassium made hot platinum IPO positive ; whereas the same couple, with sulphuric acid 1 in 40, rendered it 4’25 negative. Between these extremes is a list of thirty-four other sub- stances. This is compared with the former series, and the differences between the results are only in one or two cases important. The chief conclusion arrived at is that the currents previously obtained with mercury are really due to heat, and not to minute amounts of chemical action. The same observer also contributes memoirs on the Influence of Voltaic Currents on the Diffusion of Liquids and on Electric Osmose. In the former case the phenomena are very complex, consisting of a mixture of physical and chemical effects, chiqfly due to electrolytic changes, to differences of specific gravity, to ordinary liquid diffusion, to electrolytic transfer, and to heat of conduction-resistance. In the latter instance the experiments were similar to that made by Porrett. A vessel of thick glass divided vertically into two equal parts, had a diaphragm of biscuit porcelain about P5 millim. thick between its two cavities. The cell was held together by screw clamps. The electrodes were of sheet platinum, the current from several Grove’s pint-cells in single series, al ways in the same direction. In sixty-eight experi- ments osmose occurred in all but one — a saturated solution of potassic cyanide. It was in the same direction as the electric current, with one exception, that, namely, of bromide of barium in absolute alcohol. This single fact quite 184 POPULAR SCIENCE REVIEW. invalidates the conclusion that the direction of flow is independent of chemical composition and molecular structure of the liquid. It would appear, however, that this direction depends ‘ much more frequently upon the direction of the electric current than upon the internal architecture of the liquid.’ » A paper complementary to this, by the same distinguished physicist, con- siders the Electric currents caused by liquid diffusion and Osmose. It states that other observers have already obtained electric currents by the contact of two liquids — Nobili the first. His arrangements consisted of a series of four glass cups, each containing an electrolyte, the liquids in the two ter- minal vessels being similar, with platinum electrodes ; a second and third hind of liquid being in the two intermediate cups. The solutions were con- nected by liquids similar to those in the cups contained in glass syphons, with turned-up capillary ends. Fechner, Wild, L. Schmidt, and Wullrer, all attacked the same problem in various ways. To ascertain whether difference of facility in diffusion, caused by the action of gravity upon two portions of of solution of different degrees of concentration and of specific gravity would produce a current, twenty-five small glass tumblers were taken, each alter- nate one containing liquid of a different degree of concentration. Pctassic nitrate was the salt employed. Platinum wire electrodes completed the circuit. The liquids in the vessels were connected by means of inverted bent tubes half an inch in diameter, alternately filled with the two solutions. Where the liquids came in contact at the end of each of the tubes a wet septum of parchment paper was secured. On interposing a galvanometer a feeble current was obtained, not due to differences in the electrodes. Its direction was downwards, through the septa and surfaces of contact. With sulphate of copper and sulphuric acid, a stronger current of similar direction was obtained. Four other experiments, somewhat varied in their conditions, produced a much stronger current, in a reverse direction, from the strong solution upwards through the diaphragm into the weak one. The difference of osmose, through a porous partition, was opposite in direction to that pro- duced by difference of diffusion. The phenomenon of Regelation , originally discovered by Faraday in 1850, and extended in its physical bearings to explain glacier motion by Tyndall, has been recently made the subject of a memoir in the Annales de Chemie et de Physique, by Mons. W. Spring, Professor of the University of Liege. He adverts to the more recent researches of Helmholtz, Bottomley, and es- pecially of Tresca, on the viscosity of solid bodies, but is of opinion that we have not yet attained a satisfactory solution of the question. James Thomson and Clausius have given mathematical expression to the physical laws involved in the phenomenon, the general cases of which have been verified experimentally by Bunsen. But two substances still form excep- tions to the rule — water and bismuth. Their specific volume being greater in the solid than in the liquid state, pressure lowers, instead of raising their point of fusion. That of ice lowers 0°*0075 for each additional atmosphere of pressure. Mousson was able to melt ice completely, without the addition of any external heat, by a pressure of 13,000 atmospheres. Mons. Spring considers that the binding together of solid bodies under pressure is a much more general phenomenon, comparable to the liquefaction of gases. He has SCIENTIFIC SUMMARY. 185 subjected 83 substances, of which 8 were metals, 6 metalloids, 10 oxydes and sulphides, 32 salts, and 19 carbonaceous bodies, with 8 mechanical mixtures, to compression, either under ordinary or elevated temperatures, with the following among other results. Lead in a vacuum, under pressure equal to that of 2000 atmospheres, becomes as solid as when melted ; under 5000 it flows like a liquid. Bismuth welds easily under a pressure of 6000 atmospheres, breaking afterwards with a crystalline fracture. Pewter behaves like lead. Zinc requires 5000 atm. Aluminium and copper unite at 6000 atm. Antimony in grey powder recovers solidity and metallic lustre at 5000. Platina welds imperfectly with pressure alone. Of the three allotropic forms of sulphur, the transparent prismatic form at 5000 atm. became harder than that obtained by fusion, and probably octahedral, a form which the plastic variety also took at 6000 atm. The octahedral form itself welds easily at 3000 atm. Amorphous carbon refuses to solidify under any pressure whatever, and exhibits the most perfect elasticity. Graphite, on the contrary, as is well known, agglome- rates to a solidity equal to the native material. Peroxyde of manganese took the exact appearance of crystalline pyrolusite. Alumina became translucent, like the mineral known as Halloysite, flowing like a liquid, but showing no tendency to assume the form of corundum. Sulphide of lead became galena. Many chlorides, bromides, and iodides welded and became transparent. Mercuric iodide took a violet colour. Nitrate of potash became plastic like wax at 3000 atm., as did hyposulphite of sodium. Glass resisted at every pressure. Turf became practically coal, losing all trace of organic structure, and coking in a close vessel just like coal, a result of some geological importance. Pressure was also found to influence chemical combination. For instance, under a pressure of 5000 atms. sulphur and metallic copper com- bine perfectly. Mercuric chloride and the same metal change places, metallic mercury and cuprous chloride, free from cupric chloride, being left. M. Spring points out (1) that under compression, the attraction of particles follows the direction of the crystalline axes ; (2) that crystalloids coalesce better than amorphous bodies ; (3) that after welding, many bodies reputed solid flow like liquids. The compressing apparatus is described as consisting either of screws or powerful levers weighted at their end. Hydraulic compression is not alluded to. Musical pitch and its determination formed the subject of a recent lecture at the Royal Institution by Dr. W. H. Stone. He pointed out that absolute pitch does not exist in nature, the exceptional power of recog- nizing a note, or hearing it, being really an acquirement connected with the ‘ muscular sense’ in singers, and musical memory highly developed in organists and instrumentalists generally. After defining pitch as rapidity of vibration, he considered (1) the causes and amount of variation in different sound-producers ; (2) scientific methods of measuring pitch ; (3) the musical application of such methods. 1. Heat variations were illustrated by metallic strings, organ-pipes, har- monium-reeds, and tuning-forks. 2. The mechanical, optical, photographic, electrical, and computative methods of determining pitch, were exhibited and explained. These included 186 POPULAR SCIENCE REVIEW. an exact copy of Colonel Perronet Thompson’s Monochord , hearing a weight of 240 lbs. to produce Tenor C, and Professor McLeod’s ingenious modifica- tion of Lissajous’s figures in the cycloscope. He laid much stress on the computative method, on account of its extreme simplicity and accuracy. By it absolute was first obtained from relative pitch. Scheibler’s Tonmesser and Appunn’s reed-tonometer were exhibited, as well as a photograph of Koenig’s tuning-fork clock. 3. The problem of absolute pitch having now been satisfactorily deter- mined, its application only needed time and patience, the present state of the matter being discreditable to England. Since Handel’s time, pitch had risen about a semitone. This was attributed to (1) the excess of true fifths, as tuned to by violins, over the corresponding octaves ; (2) the rise with heat of the wind instruments ; (3) the difficulty of appreciating slow beats ; (4) the predominant effect on the ear of a sharp over a flatter note. The voice — God’s instrument — should be consulted in preference to man’s less perfect instruments. The difference, however, between the present high orchestral pitch and the French normal diapason which, as a standard, had been proved to be both accurate and convenient, is less great melodically than is often supposed. Indeed the ear, unassisted by beats, was all but unable to detect the difference. The main need of modern music was a greater familiarity with the physical principles upon which it rests. ZOOLOGY. Abyssal Crustacea of the West Indies. — Prof. A. Milne-Edwards has laid before the French Academy of Sciences a general statement of the results of his investigation of the Decapod Crustacea dredged up from great depths in the West Indian seas, by the U. S. exploring- ship Blake (Comptes Bendus, 21 February, 1831). The family Galatheidae has always been regarded as wanting in American waters ; among these collections there are forty-one species, mostly consti- tuting new genera, although thirteen of them belong to the widely distributed genera Galathea (2) and Munida (11). True Crabs do not occur at very great depths ; numerous small species are found down to about 250 fathoms, and at about 400 fathoms a new form allied to the well-known European genus, Gonoplax, was obtained. This animal, deecribed by Prof. Milne- Edwards under the name of Bathyplax, is blind, its eyes being atrophied and destitute of facets, and its orbits rudimentary. The Anomurous and Ma- crurous Decapods, on the contrary, swarm at great depths. Down to about 1800 fathoms the curious genus Willemoesia was represented ; its species are apparently most nearly related to the well-known Eryons of the Jurassic rocks, but the deep-sea forms examined by M. Milne-Edwards were blind. The Galatheidae already mentioned occurred at still greater depths, down to more than 2000 fathoms, from which depth came species of a new genus ( Galathodes ) having the eyes greatly reduced and imperfectly facetted. The most interesting types are those belonging to the family Paguridae, represented hitherto by the well-known Hermit Crabs, which, SCIENTIFIC SUMMARY. 187 although numerous in species, are all very similar and show no indi- cations of an alliance with the Macrura, such as the Shrimps and Lobsters. Among the West Indian dredgings, however, such intermediate forms seem to abound. Thus Pylocheles Agassizii is described as connecting the Hermit Crabs with the Thalassinidae ; the abdomen, instead of being soft and unsym- metrical as in the former, is composed of firm, regular rings, and terminated by a symmetrical fin. This animal lives in holes, the entrance to which it closes with its claws. In Mixtopagurus , the abdomen is more developed on the right than on the left side, and divided into seven joints, of which the first five are imperfectly calcified, and the last two large and hard. In Ostraconotus the carapace is coriaceous, and the abdomen so small that the female uses the legs of the fourth pair to hold her eggs ; the last joint but one in these limbs is widened into a palette forming a floor on which the eggs rest. Spiropagurus and Catapagurus have a very small, twisted abdomen which the animals lodge in small spiral shells, contrasting curiously with the much larger carapace and legs which remain exposed. Eupagurus discoidolis inhabits the tubular shells of Dentalium, the orifice of which it closes with its claws. Xylopagurus inhabits holes in fragments of wood and the cavities of reeds, rushes, &c. ; the cavities are open at both ends, and the Crustacean does not go into its dwelling tail foremost after the fashion of the Hermit Crabs, but crawls in and closes one aperture with its claws and the other with the end of the abdomen which is converted into an opercular shield. Among the Dromiidse there are numerous forms leading towards Homola and its allies, and the genus Homola itself is represented by two species, one of which appears to be identical with the Mediterranean II. spinifrons, thus furnishing a striking example of the wide distribution of animals inhabiting the great depths of the sea. The genus Cymopolia, of which one species in- habits the Mediterranean, possesses eight in the Caribbean Sea. The genus Ethusa, supposed to be peculiar to the Mediterranean, is also found in the American seas ; M. Milne-Edwards has described a species from the Florida reefs under the name of E. americana, but states that it differs from the Mediterranean E. mascarone only by characters of little importance. It is impossible to overrate the value of such results as the above, and M. Milne-Edwards is quite justified in commenting with some pride upon the important bearing which such investigations must have upon our conceptions of the system of Nature. As one instance of this, he indicates that the results of the Travailleur’s expedition of last year in the Bay of Biscay showed the existence, in close proximity on the Spanish coast and in the neighbouring deep water, of two distinct faunas belonging neither to the same time (geologically speaking) nor to the same climate ; and he specially calls the attention of geologists to this fact as showing that at the present day and in the same seas, there must be in course of for- mation deposits absolutely contemporaneous, but which will contain the remains of perfectly dissimilar animals. The littoral deposits will contain the types of higher organizations ; the deposits formed at great depths will contain creatures of a more ancient character, some of them presenting un- mistakable affinities with fossils of the secondary epoch, while others re- semble the larval forms of existing species. We are glad to learn that the success of last year’s expedition will induce 188 POPULAR SCIENCE REVIEW. the French Government to send out the Travailleur again this summer on a dredging expedition ; this year the scene of her labours will be the Medi- terranean. The Crustaceans referred to above are described by Prof. Milne-Edwards in the Bulletin of the Museum of Comparative Zoology in Harvard College, Vol. viii., No. 1. Terrestrial progression of CaUichthys. — According to Mr. Joseph Mawson of Bahia ( Science , December 25, 1880), the Brazilian Siluroid fish, CaUichthys asper , is very active on dry land. Mr. Mawson says : — ‘ During the rainy season the fish live in fresh-water pools. When the pools dry up in the dry season, they bury themselves in the mud, and remain there until the rains return the following year. They are noted for overland excursions. It is said that they are often met with going from one pool to another. I have had six of the fish in a narrow-necked tin of water, with some sand and mandioca meal at the bottom, for five days, and they continue active and vigorous, especially the smaller ones. These examples measure from 5 to 10 cm. in length, and I have seen them much larger. I have had them out in the garden several times. I find that they move best on smooth damp ground, and are embarrassed by sticks or other inequalities. They can jump a little vertically, but their progress on land is effected entirely by a quick wriggling motion of the body, which is nearly flat upon the ground. The paired fins (pectorals and ventrals) are extended laterally, and seem to bear little if any weight ; but they move slightly, and appear to serve to steady the body. Last night I heard a peculiar sound, and on looking around, I saw one of the fish travelling about the room. He had escaped from the tin which was in my bed-room, had fallen from the table to the floor, and j; travelled along the corridor, about 12 metres (about 40 feet), to the sola. I watched him travelling for two hours, during which time I estimate that he moved at least 90 metres. Toward the end of the two hours he seemed to flag a little, but in the earlier part his method and speed were fairly seen. He seemed to start with a sudden movement of the head or the barbels, then wriggled briskly for 5 to 10 seconds, advancing about a metre. Then he would rest for about 10 seconds, and start as before. This was kept up during the whole two hours, and I left him still moving. This morning, five hours later, I found him dead. While he was moving I spilled some water on the floor, but he crossed it ; hence I concluded that it was mud rather 1 than water of which he was in search.’ Trichinosis. — The spread of Trichinosis in American pigs is producing jl very serious consequences, not only in North America, but also in Europe, owing to the great importation of pork, hams, &c., from the United States. In France considerable alarm prevails, and the most opposite opinions seem to be held — some writers maintaining that ordinary salting is sufficient to destroy the Trichina ?, whilst others declare that salting, smoking, and even ordinary cooking, will not give the requisite safeguard. M. J. Chatin ( Comptes Rendus, 28th February, 1881), declares that the examination of the encysted Trichinae in salted provisions seems to show that these parasites are in a state of absolute functional integrity, for he says, * We know that their passage from latent life to death is regularly manifested by important modifications in the nature of the cyst ; fatty matter accumulates rapidly, V SCIENTIFIC SUMMARY. 189 then calcareous granules appear and multiply quickly, effacing all traces of the original constitution.’ None of these phenomena were presented by the Trichince observed by him. The ordinary course of experiment to decide whether the Trichince are really alive consists in heating the trichinized meat to 40° or 45° C. (104° or 113° F.), and then examining whether the encysted larvae show any signs of movement. If not, the meat is regarded as ^innocuous ; but M. Chatin holds that this conclusion must be accepted with reserve, seeing that the action of heat only reproduces one of the con- ditions necessary for the ulterior development of the parasites. His own test consisted in the administration of small quantities of trichinized salt pork to two guinea-pigs. On the fourth day diarrhoea set in, and rapidly increased; on the eighth day one of the animals died, and the other on the fifteenth day. Examination showed all the signs of acute enteritis ; and further, the intestine contained numerous adult, sexually mature Trichince. The females showed normally developed embryos, which were also met with free in the contents of the intestine. In the guinea-pig that survived till the fifteenth day, young Trichince had already got into the muscles, but had not yet become encysted. M. Bouley ( Comptes Rendus,7\h March, 1881) seems to think that there is little danger of the spread of trichinosis in France, and accounts for this supposed immunity by the fact that such provisions as might communicate the parasite are thoroughly cooked in that country, the Trichince not being able to survive exposure to a temperature of 70° C. (158° F.). In spite of such encouraging statements, the French public appear to prefer having their pork untrichinized, and M. Bouley himself has been appointed by the Government to organize a system of inspection at Havre. A Gigantic Japanese Cuttlefish. — M. Hilgendorf describes ( Sitzungsber . Gesellsch. Naturf. Freunde zu Berlin , 1880) a gigantic Cuttlefish, which was captured in the Japanese sea in 1873, and exhibited in Yedo for money as a curiosity. It did not attain the size of the specimens obtained some years ago off the coast of Newfoundland, some of which were estimated to exceed 50 feet in total length, including the long tentacular arms, while indis- putable measurements of one specimen give the length of the body as 9^ feet, and that of the long arms at 30 feet, making nearly 40 feet in all.* The Japanese Cuttlefish was, however, a sufficiently formidable animal; the length of its body (the head estimated) was about 7^ feet, and that of the longest arm preserved, 6J feet. The long tentacles had been cut off, but M. Hilgendorf estimates that when they were perfect, the total length of the animal must have been at least 20 feet. He was at first inclined to refer this Cuttlefish to the genus Ommastrephes, but, on further consideration, makes it the type of a new genus, and names it Megateutliis Martensii. The generic name is already preoccupied by Mr. Savill Kent’s Megcdoteuthis, proposed for one of the Newfoundland specimens, and it is a question whether the characters indicated by M. Hilgendorf are sufficient to separate the Japanese species generically from Architeuthis, Steenstr. Nevertheless the record of the occurrence of a gigantic squid in the Japanese seas is of interest. The Organs of Taste in Fishes. — M.E. Jourdan has presented some remarks upon this subject to the French Academy {Comptes Rendus, 21st March, 1831). — Schulze nearly twenty years ago described certain cyathiform bodies * See some observations of Prof. Terrill’s, p. 190. 190 POPULAR SCIENCE REVIEW. in the Barbel and in the tadpoles of Pelobates fuscus, which he found to agree in structure with similar bodies in the tongues of Mammalia, and was led to believe that the two sets of bodies possess the same functions. M. Jourdan has investigated several fishes, and especially the Malarmat ( Peristedion cata- phractum) at the Marine Zoological Laboratory of Marseilles, and his obser- vations confirm Schulze’s conclusions. The Malarmat (a member of the Gurnard family) possesses barbels like those of the Red Mullet ( Mullus bar- batus ), and free fine rays identical with those of the Gurnards. The barbels, which may be either tufted or isolated, are attached, to the number of ten or twelve, to the lower jaw ; two of them are always large, and present secondary ramifications. They are always furnished with small cyathiform bodies containing two kinds of cells; some, grouped in the centre, and slightly projecting at the surface of the barbel, resemble fibres with a volu- minous nucleus ; the others, arranged at the periphery, are cylindrical. These organs exist also in considerable number in the mucous membrane lining the cavity of the mouth : they are arranged serially in the pharynx, and the papillae of the rudimentary tongue have three or four of them. They are always in the epidermis. In the Mullet the cyathiform bodies are much larger. They are like those described by Schulze in the Barbel and Tench. Each corpuscle is placed at a point in the epidermis corresponding to a papilla of the dermis ; it is clearly distinguished from the cells which surround it by the dark colour it acquires by the action of osmic acid, and the aspect of the elements forming it. Each is formed of cells of two types, between which all transi- tional forms are observed ; namely, cylindrical, peripheral cells, and cells grouped in the centre of the ovoid body, which terminate in conical processes,, the points of which are not so distinct in the Malarmat. All possess a voluminous nucleus. At the base of each corpuscle is a small granular mass- formed by the varicose basal prolongations of the cells of the body ; in the' granular mass the cylinder-axes of the nervous fibres disappear, and the cells of the corpuscles originate. Identical bodies occur in the mucous membrane of the tongue and pharynx. The Gurnards have cyathiform corpuscles on the tongue ; and they pro- bably exist in the buccal mucous membrane of most fishes. If these cyathiform bodies are to be regarded as taste-organs, whether external or internal, the sense of taste appears to acquire an importance in fishes which may be justified by the nature of the medium in which the animals live. * The search for food,’ says the author, ‘ must be guided by sensitive terminations more particularly destined to the reception of gusta- tive emanations ; this explains the distribution of the cyathiform corpuscles upon external organs, exploratory apparatus, the situation of which has deceived observers, but which need no more surprise us than the existence of well-formed otoliths, far from the head, upon the last segments of Mysis .’ Giant Squids on the Newfoundland Banks. — Professor Yerrill has pub- lished ( Amer . Journ. Sci., March, 1881) an account of the occurrence of Giant Squids of the genus Arcliiteuthis in great abundance upon the Grand Banks in the year 1875. He states that he has been informed by Capt. J. W. Collins that in October of that year a great number of these animals were found floating at the surface over the Grand Banks, mostly quite dead, and more or less mutilated by birds and fishes. In a few cases they were not SCIENTIFIC SUMMARY. 191 dead, but completely disabled. They were seen chiefly between 44° and 44° SO' N. lat., and between 49° 30' and 49° 50' W. Long. From twenty-five to thirty specimens were said to have been secured by the fleet from Gloucester, Mass., and as many more were probably obtained by the vessels from other places. They were cut up as bait for codfish. Capt. Collins himself was in command of the schooner Howard, which secured five squids to her own share. They were mostly from ten to fifteen feet long, exclusive of the arms, arid averaged eighteen inches in diameter. The arms were generally mutilated, the portions left being usually three or four feet long, and, at the base, almost as thick as a man’s thigh. One specimen, when cut up, was packed into a large hogshead-cask holding about 75 gallons, which it filled. This cask would hold 700 pounds of codfish, and as the specific gravity of the Architeuthis is almost equal to that of codfish, we may take this as an approximate indication of the weight of one of these gigantic Cephalopods. Allowing for the lost parts of the arms, this specimen would probably, when entire, have weighed about 1000 pounds ; previous estimates are too high. Professor Verrill refers to other vessels which secured portions of the valuable supply of bait furnished by these great squids, and states that the E. R. Nickerson, Capt. McDonald, obtained one which had its arms, and was not quite dead, so that it was harpooned. Its tentacular arms were thirty feet long. The schooner Tragabigzanda secured three in one afternoon ; they were from eight to twelve feet long, not including the arms. Other fishermen confirm these statements, and some of them add that the 1 big squids’ were common during the same season at the 1 Flemish Cap,’ a bank some distance north-west of the Grand Banks. With regard to the cause of this remarkable mortality among these great Cephalopods, Professor Verrill suggests that it may have been due to some disease epidemic among them, or to an unusual prevalence of deadly parasites or other enemies. He indicates, however, as a point worthy of notice, that they were observed at the same season of the year when most of the speci- mens have been found on the shores of Newfoundland. This season may, perhaps, be immediately subsequent to the period of reproduction, when the animals would probably be so much weakened as to succumb easily to para- sites, disease, or any other unfavourable conditions. Disappearance of the muscles of larvce in the pupce of Dipterous Insects. — It is well known that many of the internal organs of the larvae of insects melt away, as it were, when the insect passes into the pupa state, so that the pupa may not unaptly be likened to a second egg in which new organs are produced from a formative fluid. M. Viallanes has communicated to the French Academy ( Comptes Rendus, February 21) an interesting description of his observations on the disappearance of the larval muscles in the pupae of Diptera, founded upon the examination of more than 400 transverse sections of larvae and pupae. The primitive bundles enclosed in their sarcolemma exhibit nuclei, some of which are situated just within the sarcolemma, while others are in the midst of the contractile substances of the muscle. From the first day of pupal life the primitive bundles begin to disappear, and this disappearance takes place in two modes, — 1. By the excessive activity and proliferation of the nuclei; 2. By their degeneration and death. In the first mode the sarcolemma speedily vanishes, the contractile sub- 192 POPULAR SCIENCE REVIEW. stance becomes homogeneous, and the nuclei become spherical, and soon acquire the value of complete cells. They are surrounded by a layer of protoplasm, enveloped by a membrane. In this protoplasm four or five spherical granules make their appearance, and soon attain the size of the nucleus, producing a mulberry-like mass of five or six grains enclosed in a common envelope. The enveloping membrane disappears and the grains separate, and again multiply by a process analogous to that already described. As these embryonic cells increase in number the contractile substance is absorbed, and at a more advanced stage the place originally occupied by the muscular bundle shows only a mas3 of embryonic cells engaged in constant proliferation. In the second mode the sarcolemma also disappears, and the muscular nuclei show a very distinct envelope presenting a double contour. They still retain their original lenticular form, and their centre is occupied by a small spherule composed of fine granules. These granules become fewer and fewer ; they separate and finally disappear, when the nucleus is represented only by its empty envelope. While these changes are going on the con- tractile substance gradually disappears, by a sort of melting away, but without altering the general form of the bundle, finally producing a colour- less, very finely granular substance, containing the original nuclei in any stage of the degeneration just described. Habits of Callichthys faciatus. — M. Carbonnier records some curious par- ticulars of the habits of Callichthys faciatus — a Siluroid fish from the rivers of South America. His observations are made upon specimens from the Rio de la Plata, living in his aquarium, and relate chiefly to the reproduction of the fish. He states that when about to deposit her eggs the female brings together the ventral fins in such a manner as to form a sort of pouch, in which the fertilizing elements furnished by the male fish are received and retained. The ovarian orifice is at the bottom of this sac, and through it some five or six eggs are extruded into the sac, where they are of course surrounded by a fluid charged with spermatozoids. To secure impregnation the female retains the eggs in the pouch formed by the ventral fins for a short time before finally depositing them. For the latter purpose she selects a spot, usually well illuminated, which she cleans with her mouth from all adhering vegetation, or other inconvenient objects, and then applying her abdomen to the place, opens the sac and attaches the eggs, which adhere by means of the viscosity with which they are endued. The same process is repeated until all the eggs — numbering about 250 for each female — have been laid. The young fish are developed and able to swim about in from twelve to thirteen days; but their further development is comparatively slow, as they do not appear to become adults until two years after hatching. A singular fact mentioned by M. Carbonnier is the change that has taken place with his CaUichthyes in the season of oviposition since their transpor- tation to Europe. In the Kio de la Plata the eggs are laid in October and November. After being in Europe for a year the South American speci- mens bred in August and September, 1878, and the young fish thus pro- duced have their eggs in the month of June. This would seem to indicate an adaptation to the change of climate to which the fish have been sub- jected, the seasons in South America being the reverse of those in Europe ( Comptes Itendus, G December, 1880). Twelfth Thousand. Demy 4to. boards, price 5s. [ALF-HOURS WITH THE STARS A Plain and Easy Guide to the Knowledge of the Constellations. SOWING IN TWELVE MAPS THE POSITION OF THE PRINCIPAL STAR-GROUPS NIGHT AFTER NIGHT THROUGHOUT THE YEAR. MTH INTRODUCTION AND A SEPARATE EXPLANATION OF EACH MAP. By R. A. PROCTOR, B.A., F.R.A.S. Auihcr of 1 Half- -Hours with the Telescope .’ PECIMEN of MAPS (Size Reduced to One-Sixth). Dec. 14, at 84 o’clock. „ 17, „ 8} „ „ 21, „ 8 TRUE FOR EYERY YEAR. ov. 22, at 10 o’clock. » 25, „ 9f „ i.. 29, „ 94 „ | I xii. 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The Publisher will mail this Journal to any Address in the United States, for one year, on receipt of Post Office Order for 11s. No. 19. Series. July 1881. [2s. 6d. THE POPULAR acme Emm EDITED BY W. S. DALLAS, F.L.S. Assistant-Secretary of the Geological Society. CONTENTS. The Movement of Plants. By the Bev. George Henslow, M.A., F.L.S., F.G.S. (Illustrated). The Centenary of the Discovery of Uranus. By W. F. Denning, F.R.A.S. (Illustrated). The Eye-like Spots in Fishes. By Professor H. Jeffrey Bell, M.A. (Illustrated). The Blackheath Subsidences. By t. y. holmes. Scientific Teaching. By w. Stone, m.b., f.r.c.p. REVIEWS. The Cat — Muscles and Nerves — The Brain — The Spirit of Nature — Anthropology — Monticulipora — Systematic Mineralogy— Sight — A Geologist's Notebook — Tin. SCIENTIFIC SUMMARY. Chemistry— Geology and Palaeontology — Mineralogy — Physics — Zoology. ILLUSTRATED. LONDON : DAVID BOGUE, 3 ST. MARTIN’S PLACE, TRAFALGAR SQUARE. 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GEORGE GARDEN NICOL, » JOHN SANDERSON, Esq. W Baron J. H. W. SCHRODER. C GEORGE YOUNG, Esq. ■ P. DU PRE GRENFELL, Esq. QUINTIN HOGG, Esq. Hon. HUGH M'CULLOCH. J. S. MORGAN, Esq. CHARLES W. MILLS, Esq. Manager of Fire Department— G. H. BURNETT. Manager of the Life Department — HENRY COCKBUR Secretary— F. W. LANCE. Medical Officers— A. 1J. HASSALL, M.D. ; R. C. CREAM, M.D. ; HERMANN WEBER, M.D. Solicitor— Sir W. R. DRAKE. General Manager — DAVID SMITH, F.R.S.E. FIRE DEPARTMENT. Property of every description, at home and abroad, insured at the most favourable rates. The net premiums for 1878 amounted to £915,196. Prospectuses and every information can be obtained at the CHIEF OFFICE. LIFE DEPARTMENT. The principles on which this Company w’as founded, and on which it continues to act, combine the eyj of mutual assurance with the safety of a large protecting capital and accumulated funds, and thus affori the facilities and advantages which can prudently be offered by any life assurance office. Under if principles the business of the Company continues rapidly to increase. Ninety per cent, of the whole profits is divided among the assurers on the participating scale. The profits are divided every five years. Policies indisputable after five years. Annuities of all kinds are granted, and the rates fixed on the most favourable terms. LONDON— 61 THREADNEEDLE STREET, E.C. WEST END OFFICE— 8 WATERLOO PLACE, S.W. EDINBURGH— 64 PRINCES STREET. G Henalow.daletJith. ILLUSTRATIONS OF. PL ANT MOVEMENTS . 193 THE MOVEMENTS OF PLANTS. By THE Key. GEORGE HENSLOW, M.A., F.L.S., F.G.S. [Plate V.] THE old distinction between plants and animals, that the latter can move and the former cannot, has long since been abandoned as unscientific, and only lingers as a copy-book assertion ; but that all plants, even when permanently fixed to the soil, have their stems, leaves, flower-stalks, &c., in almost perpetual motion, is a discovery of quite recent times, and notably due to the investigations of Mr. Darwin. His latest work, which bears the title of this article,* is a treatise based on the most careful and elaborate experiments on the motions effected by the different organs of plants ; and it was thought that a brief exposition of the chief of these, as well as of some movements peculiar to the parts of flowers not alluded to by Mr. Darwin, might be interesting to the readers of the Popular Science Review. The majority of the movements can be embraced under the single term circumnutation and its modifications ; it signifies a ‘ bowing around.’ The stem, leaf, or other organ, when cir- cumnutating, bends to all points of the compass successively, with a sort of rolling motion, so that the side which is upper- most in any direction becomes lowermost when it points in the opposite one. The circles or ellipses thus described by the apex of the organ, are most perfectly seen in the circumnutation of the stems of climbing plants ; other organs for the most part move in ellipses, but with frequent interpolations of zig-zags, triangular loops, &c. The projections of such motions, when observed for some hours, exhibit most complicated and intricate lines ; a great number of these projections are given by Mr. Darwin. With regard to the cause of circumnutation, Mr. Darwin says that on the whole we may at present conclude * The Tower of Movement in Plants. By Charles Darwin, LL.D., F.R.S., assisted by Francis Darwin. 8vo. London : Murray. 1880. NEW SERIES, VOL. V. NO. XIX. O 194 POPULAR SCIENCE REVIEW. that increased growth, first on one side and then on another, is a secondary effect ; and that the increased tnrgescence of the cells, together with the extensibility of their walls, is the primary cause of the movement of cir cumnutation. * It will be advisable to treat of the different organs in a definite order, so I will proceed to describe the motions of radicles, cotyledons, hypocotyls, and epicotyls of germinating seeds ; then will follow those of the stems and leaves of fully developed plants ; and finally, the movements effected by the different organs of the floral region. Radicles. — The tip of the radicle, as soon as it protrudes from the seed-coat, begins to circumnutate, and the whole growing part continues to do so, probably for as long as growth is maintained ; it presumably is aided by this motion in being guided along lines of least resistance. As soon as the radicle has protruded, geotropism at once acts upon it. If this force be identical with gravitation, it is gravitation acting in a peculiar way ; for although the radicles of germinating seeds, whether in England or at the Antipodes, point to the centre of the earth, yet the influence affects the tip only, for a length of no more than the *02 to *03 of an inch, at least, in the cabbage. This minute part, however, at once communicates some influence to a point further back, where the radicle bends downwards in response to it ; neither geotropism nor cir cum- nutation can enable the radicle to penetrate the soil. This is effected by the force due to growth both longitudinally and transversely. By means of ingenious contrivances, seeds were grown under resistance ; and Mr. Darwin found that transverse growth exerted a force, after six days, of more than 8 lbs., and vertical growth, after twenty-four hours, of at least a \ lb. The purchase for the due effect of these forces is gained partly by the seed being below the soil, aided by the root- hairs, which, in consequence of the cellulose passing into a gum-like substance, fix the radicle to the particles of the soil. The growing part, therefore, acts like a wedge of wood, which whilst slowly driven into a crevice, continually expands at the same time by the absorption of water ; and a wedge thus acting, Mr. Darwin observes, will split even a mass of rock. Another important property of radicles is their extreme sensitiveness to irritants, such as mechanical obstructions, caustic, and injuries by being cut, all of which induce the radicle to bend away from the exciting cause, as well as to the presence of moisture, which, on the contrary, induces the radicle to bend towards it. Any solid body which gives rise to * P. 2, 3. I have not here or elsewhere added inverted commas, for throughout this paper I have largely interwoven Mr. Darwin’s sentences with my own. THE MOVEMENTS OF PLANTS. 195 a permanent obstruction to a radicle, causes the latter to deviate from its path till it finds no great resistance ; and Mr. Darwin observes that this is the only-known instance of an organ turning away from an irritant. By fixing cards to one side of the tips of vertically growing radicles, they were caused to tend upwards, as if trying to escape from the cards, sometimes even forming complete circles, and in one case a radicle actually tied itself into a knot (Pl. Y. fig. 3*). The tip in the act of forming a loop, generally rubs against the upper part of the radicle and pushes off the attached card ; the loop then contracts or closes, but never disappears. The apex after- wards grows vertically downwards (fig. 2). This sensitiveness is confined to the tip for a length of from 1 mm. to 15 mm., while the upper adjoining part of the radicle, for a length of from 6 or 7 to even 12 mm., is excited to bend away from the side which has been irritated. After a time the radicle apparently becomes accustomed to the irritation, as occurs in the case of tendrils, and the irritant no longer affects its downward growth, which is resumed. After a radicle, which has been deflected by some stone or root from its natural downward course, reaches the edge of the obstacle, geotropism will direct it to grow again straight down- wards ; but geotropism is a weak force, and the radicle assists it by having its upper part, a little above the apex, sensitive to contact, but acting in a directly opposite manner to that of the tip, for it causes the radicle to hend like a tendril towards the touching object, so that as it rubs over the edge of an obstacle it will bend downwards. This downward bending coincides with that due to geotropism, and both will cause the root to resume its original course. Finally, Mr. Darwin observes,! the several co-ordinated movements by which radicles are enabled to perform their proper functions are admirably perfect. In whatever direction the primary radicle first protrudes from the seed, geotropism guides it perpendicularly downwards ; the radicles emitted from the primary are, however, only acted upon by geotropism in such a manner as to cause them to bend obliquely down- wards, unless the end of the primary radicle be cut away, then the secondary ones grow vertically downwards. The tertiary radicles are not influenced by geotropism ; hence all the rootlets grow in the most advantageous manner, and the whole soil is thus closely searched. Hypocotyls and Epicotyls. — The radicle having penetrated * The figure of the radish is not from Mr. Darwin’s work, but from a drawing made many years ago, and which would seem now to have received its explanation. t P. 196. 196 POPULAR SCIENCE REVIEW. the soil, the hypocotyl, as the axis below the cotyledons is called, begins to develope, at least in those seeds which elevate their cotyledons above ground ; but it is the plumule or epicotyl which alone does so of seeds which retain their cotyledons below the soil. In either case the organ com- mences its growth in the form of an arch, such being the result of an innate tendency in the case of the plumule to assume that form ; the inner concave surface then growing more rapidly than the outer and convex, tends to raise the summit of the arch out of the ground. The apex of the stem, being ultimately freed from the soil, soon straightens itself and becomes erect. In whatever position the seeds may lie, apogeotropism acts upon the arch, and the two legs become vertical; the entire arch circumnutates more or less the whole time as the nature of the soil permits. Mr. Darwin aptly compares the whole process of extrication of the arch from beneath the soil to a man thrown down on his hands and knees, at the same time to one side, by a load of hay falling upon him. He would first endeavour to get his arched back upright, wriggling at the same time in all directions to free himself a little from the surrounding pressure ; and this may represent the combined effects of apogeotropism and circumnutation. The man, still wriggling, would then raise his arched back as high as he could ; as soon as the man felt himself at all free, he would raise the upper part of his body, whilst still on his knees and still wriggling. This will represent the bowing backwards of the basal leg of the arch, which aids in the withdrawal of the cotyledons from the buried and ruptured seed-coats. Cotyledons. — Colytedons are in constant movement, chiefly in a vertical plane, and commonly rise up once and descend once in 24 hours ; some move much oftener, thus, those of Ipomcea coerulea moved thirteen times either upwards or down- wards in 16h 18m. As the motion when perfected gave ellipses, cotyledons maybe said to circumnutate. In a large majority of instances observed by Mr. Darwin, the cotyledons sank a little downwards in the forenoon, and rose a little in the afternoon or evening, thus exhibiting a certain periodicity in their movements, no doubt in connexion with the daily alternations of light and darkness. When the cotyledons rise or fall to such a degree as to be vertical, or at an angle of at least 60° above or below the horizon, they are said to be asleep ; the object gained being, as in leaves, to escape injury by radiation at night. Stems. — Several experiments with stems of plants of various orders, showed that they continually circumnutate ; and in the case of stem-climbers the circumnutation is of the most perfect THE MOVEMENTS OF PLANTS. 197 kind.* An interesting modification of tlie process occurs in stolons or runners, which consist of much elongated flexible branches, that run along the surface of the ground and form roots at a distance from the parent plant ; the circumnutation is so great in amplitude, that it may almost be compared with that of climbing plants. The stolons are thus aided in passing over obstacles, and in winding between the stems of surrounding plants. Peduncles. — Flower stems form no exception to axial struc- tures in the habit of circumnutating ; but the effect is curiously modified by geotropism in the case of Trifolium subterraneum, and by apheliotropism in that of Cyclamen Persicum , in both of which plants the object gained is the burying the unripe pods beneath the soil, leaves, &c. The flower-heads of Trifolium subterraneum produce but three or four perfect flowers at the base, all the other flowers above consisting only of cylindrical calyx-tubes with stiff spreading lobes, forming claw-like pro- jections (PL Y. figs. 4-6). As soon as the perfect flowers wither, they bend back upon the peduncles. This movement is due to epi nasty, a word coined to imply that the upper surface of an organ grows more quickly than the lower surface, and thus causes it to bend downwards. Whilst the perfect flowers are thus bending, the whole peduncle curves downwards and increases much in length, even from 6 to 9 inches if necessary, until the flower-head reaches the ground. At this period the younger, imperfect, central flowers are still pressed closely together, and form a rather rigid conical projection. The depth to which the flower-heads can penetrate varies from •25 to *06 inch. In the case of a plant kept in the house, a head partly buried itself in sand in 6 hours ; with plants grow- ing out-of-doors, Mr. Darwin believes that they bury themselves in a much shorter time. After the heads are buried, the central aborted flowers increase considerably in length and rigidity, and become bleached ; they gradually curve, one after the other, upwards or towards the peduncle (fig. 5). In thus moving, the long claws on their summits carry with them some earth ; hence a flower-head which has been buried for a sufficient time forms a rather large ball, the aborted flowers having caught up the earth with the claw-like sepal-lobes, act somewhat like the hands of a mole, which force the earth back- wards and the body forwards. The calyxes of all the flowers are clothed with simple and multicellular hairs (fig. 7), which, on absorbing carbonate of ammonia presented to them, exhibited protoplasmic aggrega- # For full description of twiners and other climbing plants, the reader is referred to Mr. Darwin’s work on The Movements and Habits of Climbing Plants. See also Pop. Soi. Rev. vol. v. p. 55. 198 POPULAR SCIENCE REVIEW. tion. As Mr. Darwin observes that only a few of the flower- heads, which from their position are not able to reach the ground and bury themselves, yield seeds, whereas the buried ones never failed to produce as many seeds as there had been perfect flowers, it may be reasonably conjectured that the object gained is to nourish the ripening seeds directly through their surfaces, and so to supplement root action. The capsules of Cyclamen and of the Wood Sorrel, Oxalis acetosella, are occasionally buried, but then only beneath dead leaves or moss. Leaves. — The movements of certain leaves which are said to sleep, have long been observed, but it would seem that probably all leaves and cotyledons circumnutate, and that the so-called sleep is only a remarkable modification or development of this general kind of movement, accompanied, however, by other and often complicated motions. The seat of the move- ment generally lies in the petiole, but sometimes both in the petiole and blade, or in the blade alone. The movement is chiefly in a vertical plane ; but as the ascending and descending lines never coincide, there is always some lateral movement, and thus irregular ellipses are formed. There is a periodicity in the movements of leaves, for they often or generally rise a little in the evening and early part of the night, and sink again on the following morning, this periodicity being determined by daily alternations of light and darkness, as already mentioned in the case of cotyledons. These periodic movements occur where there is no pulvinus, for where this is found, the movement is amplified into nyctitropic , or sleep- movements. Leaves, Mr. Darwin says, when they go to sleep, move either upwards or downwards ; or in the case of the leaflets of compound leaves, forwards, that is, towards the apex of the leaf, or backwards, that is, towards its base ; or again, they may rotate on their own axis without moving either upwards or downwards ; but in almost every case the plane of the blade is so placed as to stand nearly or quite vertically at night. Moreover, the upper surface of each leaf, and more especially of each leaflet, is often brought into close contact with that of the opposite one, as the upper surfaces appear to require more protection than the lower. The nyctitropic movements of leaves and cotyledons are effected in two ways, firstly, by means of pulvini, which become ultimately more turgescent on opposite sides ; and secondly, by increased growth along one side of the petiole or mid- rib, and then on the opposite side. This difference between the two means of movement consists chiefly in the turgescence of the cells of a fully-developed pulvinus not being followed by THE MOVEMENTS OF PLANTS. 199 growth. The movements effected by growth on the alternate sides are confined to young growing leaves, whilst those effected by means of a pulvinus last for a long time. The evil effects which result if sleeping leaflets be prevented from pressing their upper surfaces together, so as to protect them from radiation, were well seen in experiments of Mr. Darwin’s, in which he pressed down the leaflets of Oxalis, Marsilia, &c., so that they could not bring their upper surfaces into contact ; the result was that the leaves were killed. Thus of twenty-four leaves of Marsilia extended horizontally, exposed to the zenith and to unobstructed radiation, twenty were killed and one injured, whilst a relatively very small proportion of the leaves, which had been allowed to go to sleep with their leaflets vertically dependent, were killed or injured. Mr. Darwin noticed that the difference in the amount of dew on the pinned open leaflets and on those which had gone to sleep, was generally conspicuous, the latter being sometimes absolutely dry, whilst the leaflets which had been horizontal were coated with large beads of dew. Another fact observable was that when leaves were kept motionless, they are more liable to injury than when they were slightly waved about by the wind, and thus got a little warmed by the surrounding air. Cotyledons, as well as leaves, may sleep ; the former seem to do so more commonly than leaves. Of 153 genera observed by Mr. Darwin, one or more species of twenty-six of these genera placed their cotyledons at night so as to stand vertically, having generally moved through an angle of at least 60°. In a large majority of genera the movement is a rising one. In all the species of Oxalis observed by Mr. Darwin, the cotyledons are provided with a pulvinus ; and he adds that this organ has become more or less rudimentary in 0. corniculata , in which the amount of upward movement of the cotyledons at night is very variable, but never enough to be called sleep. Similarly, in the Leguminosse, all the cotyledons which sleep have pulvini. As this organ has been referred to several times, it will be as well to describe it. It constitutes a cushion or joint, and consists of a mass of small cells, usually of a pale colour in the case of that attached to cotyledons, from the absence of chlorophyll, and having a convex outline. The development of a pulvinus follows from the growth of the cells over a small defined space of the petiole being almost arrested at an early stage. As a pulvinus is formed by this arrestment of the growth of its cells, movements dependent on their action may be long continued without any increase in length of the part thus provided; and such long-continued movements seem to be one chief end gained by the development of a pulvinus. 200 POPULAR SCIENCE REVIEW. It will be desirable now to give a few illustrations of nye- titropic movements from Mr. Darwin’s observations. Averrhoa bilimbi (PL Y. fig. 8). — -The leaflets of tbis plant move spontaneously in a very marked manner during tbe day, are sensitive to touch, and sleep at nigbt, when the leaflets hang vertically down and motionless. Lupinus. — The digitate leaves of this genus sleep in three different ways. One of the simplest is that all the leaflets become steeply inclined downwards at night, having been horizontal during the day, as those of L. pilosus (PI. Y. figs. 9, 10), when asleep are often inclined at an angle of 50° beneath the horizon. In L. Hartwegii and L. luteus , the leaflets, instead of moving downwards, rise at night, forming a hollow cone with moderately steep sides. With several other species, the position is remarkable. On the same leaf the shorter leaflets, which generally face the centre of the plant, sink at night, whilst the longer ones on the opposite side rise, the intermediate and lateral ones merely twisting on their own axis ; the result is that all the leaflets on the same leaf stand at night more or less inclined, or even quite erect, forming a vertical star. Melilotus. — The species in this genus sleep in a curious fashion. The three leaflets of each leaf twist through an angle of 90°, so that their blades stand vertically at night, with an edge presented to the zenith ; the two lateral leaflets always twist so that their upper surfaces are directed towards the terminal leaflet. This latter leaflet moves in another and more remarkable manner, for whilst its blade is twisting and becom- ing vertical, the whole leaflet bends to one side, and invariably to the side towards which its upper surface is directed ; so that if this surface faces (say) the west, the whole leaflet bends to the west, until it comes into contact with the upper and vertical surface of the western lateral leaflet. Thus the upper surface of the terminal and of one of the two lateral leaflets is well protected. It may be added that the petioles and sub- petioles continuallv circumnutate during the whole twenty-four hours. (PI. Y. figs. 11, 12, 13.) Trifolium repens. — During the day, the leaflets of this plant are expanded horizontally (PL Y. fig. 14), but at night the two lateral leaflets twist and approach each other, until their upper surfaces come into contact ; at the same time they bend downwards in a plane at right angles to that of their former position, until their mid-ribs form an angle of about 45° with the upper part of the petiole, this change of position requiring a considerable amount of torsion in the pulvinus. The terminal leaflet merely rises up without any twisting, and THE MOVEMENTS OF PLANTS. 201 bends over until it rests on and forms a roof over the edges of tbe now vertical lateral leaflets (fig. 15). Coronilla rosea. — This plant affords an instance of leaflets rising at night from having been horizontal during the day. The leaflets at the same time bend backwards towards the base of the petiole, until their mid-ribs form with it angles of from 40° to 50° in a vertical plane (PI. Y. fig. 16). Cassia corymbosa, during the day ; and the same, asleep, at night. Cassia. — The nyctitropic movements of the leaves in many species of Cassia are highly complex. Mr. Darwin’s observa- tions were made chiefly on C. floribunda and corymbosa, and he furnishes the following description. The horizontally extended leaflets sink down vertically at night, but not simply, as in so many other genera, for each leaflet rotates on its own axis, so 202 POPULAR SCIENCE REVIEW. that its lower surface faces outwards. The upper surfaces of the opposite leaflets are thus brought into contact with one another beneath the petiole, and are well protected, as shown in the woodcut.* The rotation and other movements are effected by means of a well- developed pulvinus at the base of each leaflet, as could be plainly seen when a straight, narrow black line had been painted along it during the day. The two terminal leaflets in the daytime include rather less than a right angle, but their divergence increases greatly whilst they sink downwards and rotate, so that they stand laterally at night, as may be seen in the figure ; moreover, they move somewhat backwards, so as to point towards the base of the petiole. In one instance, Mr. Darwin found that the mid-rib of a terminal leaflet formed at night an angle of 36°, with a line dropped perpendicularly from the end of the petiole. The second pair of leaflets likewise moves a little backwards, but less than the terminal pair ; and the third pair moves vertically downwards, or even a little forwards. Thus all the leaflets in those species which bear only three or four pairs, tend to form a single packet, with their upper surfaces in contact and their lower surfaces turned outwards. Lastly, the main petiole rises at night, but with leaves of different ages to very different degrees ; thus some rose through an angle of only 12°, and others as much as 41°. The influence of light upon the movements of plants is various. Thus the so-called heliotropic movements are deter- mined by the direction of the light, whilst periodic movements are affected by changes in its intensity. On the other hand, apheliotropism implies that a plant bends from the light, a rare phenomenon, at least in a well-marked degree. Parts of plants under the influence of diaheliotropism place themselves more or less transversely to the direction whence the light proceeds, and are thus fully illuminated. Lastly, some leaves rise or sink or twist so as to avoid great intensity of light. Such a phenomenon, Mr. Darwin suggests, should be called paraheliotropic. All these movements consist of modified circumnutation. Space forbids a detailed description of these effects ; but one curious result of Mr. Darwin’s investigation is worth recording, and that is, the transmitted effects of light. When, for example, the cotyledon of Phalaris canariensis is exposed to light, the upper part bends first, and afterwards the bending gradually extends to the base, and even a little below the ground. By protecting the whole upper half of the cotyledon from light, the lower part, though, fully exposed to light, was prevented from becoming curved. Hence it is to be * I am indebted to the courtesy of Mr. Darwin for the loan of the blocks for these figures. THE MOVEMENTS OF PLANTS. i 203 concluded that when seedlings are freely exposed to a lateral light, some influence is transmitted from the upper to the lower part, causing the latter to bend. Flowers. — There are many instances of the various parts of flowers moving under the influence of stimuli ; hut the imme- diate causes in the different cases have not been so thoroughly investigated as by Mr. Darwin in the case of the vege- tative organs, and at present, therefore, but little can be said beyond the fact that they do move. Thus, commencing with bracts, it may easily be seen how the erect bracts of the involucre of the dandelion become reflexed as soon as the fruit is ripened, thus allowing the parachute-like achenes to escape easily. Moving corollas are very numerous. A large series of plants might be mentioned of which the corollas close up, either as soon as the sun is obscured, as Mesembryanthemum, Anagallis arvensis, Convolvulus , &c., or else at evening, such as many Compositse, including the Daisy and Dandelion, re-expanding on the return of light. Conversely, some night-flowering plants unfurl their petals only at night, coiling them up by day. As an illustration Silene nutans may be taken, concern- ing which Dr. Kerner tells us * that a flower lasts three days and three nights ; with the approach of dusk the bifid limbs of the petals spread out with a flat surface, and fall back upon the calyx. In this position they remain through the night ; curl- ing themselves up into an incurved spire and becoming longitudinally creased at the same time, on the return of sunlight and a warm temperature. Ho sooner does evening return, than the wrinkles disappear, the petals become smooth, uncurl themselves, and falling back against the calyx, the corolla is again expanded (PL Y. figs. 17, 18). In the Pea family, or Leguminosse, there are several instances of the corolla having a power to move when irritated. Thus in the genera Genista and Indigo , the claws of the petals act like springs kept in a state of tension ; for when the corolla is touched, as by an insect in search of honey, the claws sud- denly curl downwards, and the petals consequently drop vertically, while the stamens, previously concealed within the keel petals, are violently thrown upwards, showering* the bee with pollen, f The movement of stamens is perhaps more curious, and apparently intimately connected with the phenomenon of insect fertilization. As an example of slow movement, Parnassia palustris may be mentioned. In this flower, each stamen in succession rises up, places the anther on the stigma, and having shed its pollen, retires and falls back upon the petals. Each * Flowers and their Unbidden Guests, p. 132. t Journ. of Linn. Soc. vol. ix. p. 355, and vol. x, p. 468. 204 POPULAR SCIENCE REVIEW. stamen occupies about twenty-four hours in rising up and discharging its pollen, and takes about the same time to recede, the whole period being eight days, but varying accord- ing to circumstances of temperature, moisture, &c.* * * § Berberis furnishes an instance of rapid motion ; for if the stamens be touched at the base of the filament, they instantly spring forward and strike the stigma, having previously lain on the surface of the spreading petals. The effects of the irritation on the filament of Berberis has been observed and described by M. E. Heckel. j* It appears that the cells of the irritable part are arranged in a parallel manner (the back of the filament being insensible). Their contents are yellow and disseminated throughout the cavity. After irritation, they undergo aggregation and contract into the centre of the cell, and the cell- wall is striated transversely. The cells of the back of the filament are contracted in repose, but extended in irritation. The stamens of the common Lucerne, Medicago sativa , as also of other species of that genus, suddenly curve upwards and remain rigidly fixed in an arched condition, having been previously horizontal. + Mr. Darwin has described numerous instances in the family Orchidaceae, in which the pollinia, as of the common Orchis mascula and others, or of Catasetum, &c., have remarkable powers of movement ; in the former cases slow, but in the latter, rapid. In every case there is discernible some special adaptation to the fertilization of the flowers by insect aid.§ Styliclium affords another illustration of rapid motion. In this flower the stamens and style are consolidated into a column, which is curiously bent and hangs over one side of the flower. If it be touched near the base, it instantly flies over to the other side. A very similar motion occurs in the pistil of Maranta. Some flowers have the stamens in a certain position on first expanding, but they take up another position subsequently. This I found to be the case with AJisma Plantago. On first expanding, the stamens spread out, their anthers being extrorse, but afterwards they curl backwards over the stigmas, thereby in all probability effecting self-fertilization. In several flowers of different species, the filaments retire after the anthers have shed the pollen or fallen off, as in the lemon - scented and oak-leafed Pelargoniums, and in Teucrium Scorodonia, or wood-sage. In both of these, the anthers mature some time * Baxter’s British Flora, vol. i. (70). t Bull. Soc. Bot. Fr., 1874, vol. xxi. p. 208. t Journ. of Linn. Soc. vol. ix. p. 827. § See Fertilization of Orchids. THE MOVEMENTS OF PLANTS. 205 before the stigmas, and assume a position adapted to insects to transport their pollen. Subsequently the filaments bend away, and the styles now take up the same position that the filaments had previously held (Pl. Y. figs. 19-22). Space will not allow further descriptions ; but enough has now been said to show how extensive and varied are the movements effected by the different organs of plants, and the advantages accruing to them by possessing such powers of motion. EXPLANATION OF PLATE V. Figs. 1, 2, 8-16, after Darwin. Figs. 4-7, 1 9-22, ad nat. Figs. 17, 18, after Kerner. Figs. 1 and 2. Zea mags ; radicles excited to bend away from little squares of card attached to one side of their tips. In fig. 2, the card has been rubbed off. Fig. 3. A radish, of which the radicle had tied itself into a knot, probably in the same manner as in the case described and figured by Mr. Darwin, by the apex continually moving away from some obstruction, until it had passed through the loop, as seen in fig. 2. Reduced one-half. Fig. 4. Pendulous head of florets of Trifolium subterraneuin ; the fertile flowers reflexed, the abortive still erect, forming a vertical cone. Fig. 5. The same, with abortive florets, now developed and becoming reflexed. Fig. 6. A barren floret, enlarged. It consists of the rigid ‘ calyx-tube,’ supporting claw-like sepal lobes. Fig. 7. Multicellular hairs from the calyx, which exhibit aggregation under the process of absorption of nitrogenous matters. Figs. 4-7 enlarged. Fig. 8. Leaf of Averrhoa bilimbi, asleep, with its leaflets pendulous ; much reduced. Fig. 9. Leaf of Lupinus pilosus seen vertically from above, by day. Pig. 10. Leaf of the same seen laterally, at night. Figs. 9 and 10 reduced. Fig. 11. Leaf of Melilotus officinalis, during daytime. Fig. 12. Leaf of the same, asleep. Fig. 13. Leaf of same, asleep, seen vertically from above. Figs. 11-13 enlarged. Fig. 14. Leaf of Trifolium repens, during the day. Fig. 15. Leaf of same, asleep, at night. Fig. 16. Leaf of Coronilla rosea, asleep, with its leaflets thrown upwards. Fig. 17. Flower of Silene nutans, by night, the petals unrolled. Fig. 18. The same, by day, the petals being rolled up. 206 POPULAR SCIENCE REVIEW. Fig. 19. Flower of oak-leafed Pelargonium, to show the position of the stamens before fertilization. The style and stigmas immature. Fig. 20. The same, with filaments reflexed after fertilization ; the anthers have fallen. The stigmas are now in the position of the anthers. Fig. 21. Flower of Teucrium Scorodonia, to show the position of the stamens before fertilization. Fig. 22. Same, after fertilization, the stamens having retired, while the stigmas now occupy their position. 207 THE CENTENARY OF THE DISCOVERY OF URANUS. By W. F. DENNING, F.K.A.S. THE year 1781 was signalized by an astronomical discovery of great importance, and one which marked the epoch as memorable in the annals of science. A musician at Bath, William Herschel by name, who had been constructing some excellent telescopes, and making a systematic survey of the heavens, observed an object on the night of March 13 of that year, which ultimately proved to be a large planet revolving in an orbit exterior to that of Saturn. The discovery was as unique as it was significant. Only five planets, in addition to the Earth, had hitherto been known ; they were observed by the ancients, and by each succeeding generation ; but now a new light burst upon men. The genius of Herschel had singled out from the host of stars which his telescope revealed, an object, the true character of which had evaded human perception for thousands of years ! The centenary of this remarkable advance in knowledge naturally recalls to mind the circumstances of the discovery, and makes us inquisitive to know what new facts have been gleaned of Herschel’ s planet now that a hundred years have passed away and we are enabled to look back and review the vast amount of labour which has been accomplished in this wide and attractive field of astronomical research. We may learn what new fea- tures have been discerned of the new body, and what additional discoveries in connexion with other planets, unknown in Herschel’ s day, have been effected by aid of the powerful tele- scopes which have been devoted to the work. We do not, how- ever, intend dealing with the general question of planetary discovery, for at a glance we are impressed with its magnitude. While a century ago five planets only were known, we now have some 230 of these bodies, and the stream of discovery flows on without abatement through each succeeding year. 208 POPULAR SCIENCE REVIEW. The detection of Uranus seems, indeed, to have been tbe pre- lude to many similar discoveries, and to have offered the incen- tive to greater diligence and energy on the part of observers in various partg of the world. Many great discoveries have resulted from accident ; and the leading facts attending that of Uranus prove that in a large measure the result was brought about in a similar way. llerschel, as he unwearyingly swept the heavens night after night, was in quest of sidereal wonders — such as double stars and nebulae, and he happened to alight upon the new planet in a purely chance way. He had no expectation of finding such a remarkable object, and indeed, when he had found it, wholly mistook its character. There could be no doubt that it was a body wholly dissimilar to the fixed stars, and it was equally certain that it could not be a nebula. It had a perceptible disc, for when it had first come under the critical eye of its discoverer he had noticed immediately that its appearance differed widely from the multitude of objects which crossed the field of his telescope. He had been accustomed to see hosts of stars pass in review, and their aspect was in one respect similar, namely, they were invariably presented as points of light incapable of being sensibly magnified, even with the highest powers. True there was a great variety of apparent brightness in these objects, and a singular diversity of con- figuration, but there was no exception to the invariable feature referred to. The point of light was constant, and no striking exception was anticipated until one night — March 13, 1781 — llerschel being intently engaged in the examination of some small stars in the region of Gemini , brought an object under the range of his telescope, which his eye at once selected as one of anomalous character. Applying a higher power, he noticed that it exhibited a planetary disc, but his instrument failed to define it with sufficient distinctness, and hence he became doubtful as to its real nature. The object was found to be in motion, and subsequent observations led him to the assumption that it must be a comet of rather exceptional type. This appeared to be the best explanation of the strange body, for history contained many records of curious comets, some of which were observed as nearly circular patches of nebulous light, and probably of similar aspect to the object then visible ; and apart from this, it must be remembered that the idea of a large planet exterior to Saturn was a fact of such momentous import, that llerschel, with a due regard to that modesty which accompanies true genius, refrained from attaching such an inter- pretation to his observations. He was content to direct the notice of astronomers to it as a phenomenon requiring close attention, and- suggested that it might be a comet in conse- THE CENTENARY OF THE DISCOVERY OF URANUS. 209 quence of its motion and tlie faint, and somewhat ill- defined character of its appearance. From the earliest ages five planets only were known, and AURIGA *■ 0 Castor *0 * * Pollux ♦, 9 ■ * ' * GEMINI * X * A l racy on CANIS MINOR TAURUS Uranus * * * H r * *V- K * Bctelyeuse TBeliatrix ORION ;**v