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the pitchstone and porphyry coulées of the Scùr flowed. Vast, therefore, as the period must be which is chronicled in the huge piles of volcanic beds forming our dolerite plateaux, we must add to it the time needed for the excavation of parts of those plateaux into river-valleys, and the concluding period of volcanic activity during which the rocks of the Scùr of Eigg were poured out. 5. Lastly, from the geology of this interesting island we learn, what can be nowhere in Britain more eloquently impressed upon us, that, geologically recent as that portion of the Tertiary periods may be during which the volcanic rocks of Eigg were produced, it is yet separated from our own day by an interval sufficient for the removal of mountains, the obliteration of valleys, and the excavation of new valleys and glens where the hills then stood. The amount of denudation which has taken place in the Western Islands since Miocene times will be hardly credible to those who have not adequately realised the potency and activity of the powers of geological waste. Subterranean movements may be called in to account for narrow gorges, or deep glens, or profound sea-lochs; but no subterranean movement will ever explain the history of the Scùr of Eigg, which will remain as striking a memorial of denudation as it is a landmark amid the scenery of our wild western shores. Prof. Haughton inquired

whether Mr. Geikie's attention had been called to the Morne Mountains in Ireland, which seemed to present some analagous phenomena to those described in the paper. In the Morne district were dykes of dolerite, pitchstone, and other volcanic rocks of the same constitution as those of Antrim. He believed that a chemical examination of these rocks in different districts would prove their common origin. The evidence in Antrim was conclusive as to their Tertiary age in Ireland, and he was glad to find that the view of their belonging to a different age in Eigg was erroneous. Prof. Ramsay had hitherto believed in the Oolitic age of these trap-rocks in Eigg, but accepted the author's views. The interbedding of volcanic beds among the Lower Silurian beds in Wales was somewhat analogous. He was glad to find the history of these igneous rocks treated of in so geological a manner, instead of their being regarded from too purely a lithological and mineralogical point of view. The great antiquity of these Middle Tertiary Beds had, he thought, been most admirably brought forward in the paper, as well as the enormous amount of denudation; and he would recommend it to the notice of those who had not a due appreciation of geological time. Mr. Forbes hoped that the geologist would remember that his father was a mineralogist. It was refreshing to find a paper of this kind brought before the Society, as it was to be regretted that the details of mineralogy were so little studied in this country when compared with the Continent; and this he attributed to the backward state of petrology (admitted by Mr. Geikie) in this country. He quite agreed in the view of the Tertiary age of these rocks. With regard to the terminology employed by the author, he objected to the use of the word dolerite, as distinct from basalt; basalt properly comprised, not only dolerite, the coarse-grained variety, and anamezite, the finelygrained variety, and the true basalt, but also trachylite, which was frequently confounded with pitchstone. All four names merely referred to structure, and not to composition. Mr. Geikie, in reply, stated that he had not examined the Morne Mountains. He had not in any way wished to disparage mineralogy, but, on the contrary, had attempted to classify the different rocks according to their petrological character. He used the term dolerite in the same sense as the German mineralogists, both as the generic name for the whole series, and also for the coarser variety of basalt. 3. "On the formation of Cirques,' and their bearing upon theories attributing the excavation of Alpine Valleys mainly to the action of Glaciers," by the Rev. T. G. Bonney, M.A., F.G. S. The paper described a number of these remarkable recesses, which, though not restricted to the limestone districts of the Alps, are best exhibited in them. The author gave reasons why he could not suppose them to have been formed either as craters of upheaval, or by the action of the sea, or by glacial erosion. With regard to the last he showed that, even if glaciers had been the principal agents in excavating valleys, there were some cirques which could not have been excavated by them; and then went on to argue from the fact that glaciers had occupied cirques, and from the relation between them and the valleys, that they could not be attributed to different agents. He also showed that commonly the upper part of the valley, where the erosive action is perhaps least, is very much the steepest, and urged other objections to the great excavatory powers often attributed to glaciers. He then described

one or two cirques in detail, and showed that they were worked out by the joint action of many small streams, and of the usual mete ric agents working upon strata whose configuration was favourable to the formation of cliffs. Mr. Whitaker suggested an analogy between the cirques and the combes in our own limestone countries. Mr. Geikie regarded the cirques as analogous with the combes of Wales and the corries of Scotland. They were not, however, confined to limestone districts, but occurred also in gneiss and granite rocks. He thought that the shape was much influenced by the bedding and jointing of the rocks, as there was an evident connection between these and the shape of the combes. He could not, however, see his way to account for the vertical cliffs surrounding the cirques. The Rev. T. G. Bonney, in reply, observed that though cirques were not confined to limestones, the finest instances occurred in such rocks. When cirques occurred in crystalline rocks, the talus was usually much larger than in limestone.-The following specimens were exhibited: Specimens of Fossil Fish-remains from the Lias of Lyme Regis; exhibited by Sir P. de Malpas Grey Egerton, in illustration of his paper.

Royal Society of Literature, April 26.—Mr. Hyde Clarke read a paper on the "Classic Names of Rivers," more particularly in Greece, Asia Minor, and Italy. After referring to the discoveries in the stone period by Mr. Finlay and others, and to the megalithic and cyclopean structures, he proceeded to consider what evidence was afforded by topographical nomenclature of the populations which preceded the Hellenic. He showed that the river-names in the classic regions conformed with each other, and that this was not attributable, as supposed, to Hellenic colonisation. These names also conform to those of India, and of the ancient world generally; but the explanation was not to be found in Aryan etymologies, but that it was to be sought in earlier forms. These are represented in the languages of the Caucasus, of which the Georgian, Suan, Latian, and Lesghian afford examples now. With these the Thracian and the languages of Asia Minor corresponded. The local facts gave colouring to the legends of the occupation and invasion of Attica by the Amazons, and of the existence in Europe of a Thracian population allied to that of Asia. The eastern connection of the Etruscan and Italian populations, too, was to be accounted for as with the Caucasus, and not with America. He referred likewise to the influence of the river-names on classic mythology, and particularly on the nomenclature of Tartarus.

Linnean Society, April 20.-Notes on Mr. Murray's paper on the Geographical Relations of the chief Coleopterous Faunæ, by Dr. Roland Trimen. The author considered that the argu ment of a continuity of land at a previous epoch is too often resorted to to explain the occurrence of the same species of He entered in considerable insects in widely remote countries. detail into the chief features of the distribution of the genera and species of Coleoptera, especially at the Cape; laying much stress on the difficulty which introduced species find in establishing themselves in soil already well stocked.

Society of Biblical Archæology, April 4.-Dr. S. Birch, F.S.A., president, in the chair.-Mr. Henry Theodore Bagster, Mr. Richard Bosanquet, Mr. A. W. Franks, M. A., V.P.S.A., &c., and Mr. Burnett Tabrum were duly elected members of the society. The Secretary read a paper communicated by Mr. Henry Fox Talbot, F. R.S., &c., "On an Eclipse mentioned on an Assyrian Tablet." The tablet in question is preserved in the British Museum, and is marked 154 and 1226. The translation runs thus: "To the King of the World -My Lord, Thy servant, Kukuru, sends this:-May Assur, the Sun, and Marduk be propitious to my Lord the King in his journey from his kingdom to the land of Egypt! I inform his Majesty that in the month of Su there was an Eclipse. Five portions of the full orb were obscured. Let the King be of tranquil mind, since the eclipse of the month of Su portends good fortune to the King." The translator proceeded to identify this eclipse thus recorded with one which took place in the seventh warlike expedition of Assurbanissal against Tiumman, King of Elam. The next meeting was then announced to take place on Tuesday, 2nd proximo, to which date the meeting was then adjourned.

DUBLIN

Royal Irish Academy, April 10.-Rev. T. H. Jellett, president, in the chair. Prof. Hennessy, F.R.S., read a paper On the Floatation of Sand by the incoming tide at the Mouth of a Tidal River. During the course of a tour along our

western coast, in the summer of 1868, the following incident came under my notice; and, although I made a note of the facts at the time, I have never hitherto made them the subject of a scientific communication: On July 26, when approaching the strand at the river below the village of Newport, County Mayo, I noticed what appeared to be extensive streaks of scum floating on the surface of the water. As it was my intention to bathe, I was somewhat dissatisfied with the appearance of the water, until I stood on the edge of the strand, and I then perceived that what was apparently scum, seen from a distance, consisted of innumerable particles of sand, flat flakes of broken shells, and the other small débris which formed the surface of the gently-sloping shore of the river. The sand varied from the smallest size visible to the eye up to little pebbles, nearly as broad and a little thicker than a fourpenny piece. Hundreds of such little pebbles were afloat around me, and it is probable that the flakes of floating matter seen farther off contained also a considerable proportion. The air during the whole morning was perfectly calm, and the sky cloudless, so that, although it was only half-past nine, the sun had been shining brightly for some hours on the exposed beach. The upper surface of each of the little pebbles was perfectly dry, and the groups which they formed were slightly depressed in curved hollows of the liquid. The tide was rapidly rising, and, owing to the narrowness of the channel at the point where I made my observations, the sheets of floating sand were swiftly drifting farther up the river into brackish and fresh water. On closely watching the rising tide at the edge of the strand, I noticed that the particles of sand, shells, and small flat pebbles, which had become perfectly dry and sensibly warm under the rays of the sun, were gently uplifted by the calm, steadily-rising water, and then floated as readily as chips or straws. I collected a few specimens of these little objects, but I regret that they have been since mislaid. This phenomenon, it is scarcely necessary to say, is due to molecular action, such as accompanies the familiar experiment of floating needles on the surface of a basin of water. Although the specific gravity of the floating objects exceeds that of the fluid on which they rest, the principle of Archimedes still holds good, because the displacement of liquid produced by the body is considerably greater than the volume of the body itself. In the case of a floating needle, the repulsion of the liquid from the polished surface of the metal presents a groove, whose magnitude is obviously many times greater than the needle; but in the case of the floating pebbles this was not so manifest. The attraction of the molecules of water for one another produces, as is well established, a tension at the surface of the liquid, which, although extremely feeble, and generally noticed only in connection with capillary phenomena, yet interposes some resistance to the intrusion of foreign substances. I have floated small flat pebbles, similar in size and appearance to the largest of those observed floating on Newport river, for more than six days, while fragments of shells, and thin pieces of slate as broad as a sixpenny-piece, have continued to float much longer. These little bodies occasionally sank from the gradual absorption of water, but much more frequently from some accidental motion of the vessel containing the liquid. It is manifest that the floatation of sand in a tidal estuary, as in the instance I have seen, can occur only under favourable conditions. The shores must be very gently inclined, the air perfectly calm, and the weather dry and warm. Under these circumstances thin cakes or sheets of sand may not only be uplifted by the water, but if the tide flows rapidly they may continue to float sufficiently long to allow many of them to be drifted far from their original place up to the higher limit of the brackish water. In this way fragments of marine shells and exuviæ might become mingled with those belonging to fresh water. The conditions favourable for sand floatation must exist during calm weather in a very high degree of perfection on the sandy shores of tidal rivers in tropical and subtropical districts of the earth. As this phenomenon can take place only with the rising tide, and never with the falling tide, the result must generally be favourable to the transport of sand and marine débris in the direction of the flow of flood tide; and this may sometimes hold good along a coast as well as on the shores of a tidal estuary. Geologists, as far as I am aware, have not hitherto noticed this phenomenon in connection with the formation of stratified deposits by the agency of tides and rivers, although they have paid great attention to the influence of the molecular resistance of water to the sinking of very minute solid substances, with the view of explaining the wide surface over which matter held in suspension by wa'er may be spread when ultimately deposited over the sea

bottom.-Prof. W. King read a paper, by himself and Prof. Rowney, "On the Mineral Origin of the so-called Eozoon Canadense." It was resolved to purchase the Bell and Bell-Shrine of St. Patrick, from Dr. C. Todd, for the sum of 500/.

BOOKS RECEIVED

ENGLISH.-Travels in the Air: J. Glaisher, 2nd edition (R. Bentley).The Natural History of Plants: H Baillon, vol. 1, translated by N. Hartog (L. Reeve and Co.).-Primitive Culture, 2 vols. : E. B. Tylor (J. Murray). -On Aphaxia, or Loss of Speech: Dr. F. Bateman (Churchill).

FOREIGN-(Through Williams and Norgate)-Archiv für Anthropologie, vol. iv.-Zeitschrift der oesterreichischen Gesellschaft für Meteorologie, vol. v.-Compendium der chirurgischen Pathologie u. Therapie: Dr. C. Heitz

mann.

DIARY

THURSDAY, MAY 4.

ROYAL SOCIETY, at 8.30.-On the Structure and Affinities of the Gwynia Annulata (Dunc.), with Remarks upon the Persistence of Paleozoic Types of Madreporaria: Prof. Duncan, F.R.S.--On Molybdates and Vanadates of Lead, and on a new Mineral from Leadhills: Dr. A. Schrauf. SOCIETY OF ANTIQUARIES, at 8.30.-Roman Villa at Beddington: J. Addy. -Antiquities from Cyprus: J. B. Sandwith.

LINNEAN SOCIETY, at 8-The phenomena of Protective Mimicry, and its
bearing on the Theory of Natural Selection as illustrated by the Lepidop-
tera of the British Islands: Raphael Meldola, F. C.S.-On the Ascala-
phida: R. McLachlan.
CHEMICAL SOCIETY, at 8.- On the Productive Powers of Soils in relation to
the Loss of Plant Food by Drainage: Dr. Voelcker, F.R.S.
ROYAL INSTITUTION, at 3.-On Sound: Prof. Tyndall.
LONDON INSTITUTION, at 7.30.-On Economic Botany: Prof. Bentley.
FRIDAY, MAY 5.

GEOLOGISTS' ASSOCIATION, at 8.-On the Fauna of the Carboniferous Epoch:
H. Woodward, F.G.S.
ROYAL INSTITUTION. at 9.-On Russian Folk-Lore: W. R. S. Ralston.

SATURDAY, MAY 6.

ROYAL SCHOOL OF MINES, at 8.-Geology: Dr. Cobbold, ROYAL INSTITUTION, at 3.-On the Instruments Used in Modern Astronomy: J. N. Lockyer, F.R.S.

MONDAY, MAY 8. ROYAL GEOGRAPHICAL SOCIETY, at 8.30. ROYAL INSTITUTION, at 2.-General Monthly Meeting. LONDON INSTITUTION, at 4.-On Astronomy: R. A. Proctor, F.RA S. (Educational Course.)

TUESDAY, MAY 9.

PHOTOGRAPHIC SOCIETY, at 8.
ROYAL INSTITUTION, at 3.-On Force and Energy: Charles Brooke, F.R.S.
WEDNESDAY, MAY 10.

SOCIETY OF ARTS, at 8.-On the Application of Steam to Canals: Geo. Edward Harding, C. E.

GEOLOGICAL SOCIETY, at 8.-On the Ancient Rocks of the St. David's Promontory, South Wales, and their Fossil Contents: Prof. R. Harkness. F.R.S., and Henry Hicks.-On the Age of the Nubian Sandstone: Ralph Tate, F.G.S.-On the Discovery of the Glutton (Gulo luscus) in Britain: W. Boyd Dawkins, F.R.S.

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THURSDAY, MAY 11, 1871

THE PROPOSED COLLEGE OF PHYSICAL

A

SCIENCE AT NEWCASTLE-UPON-TYNE FEW weeks ago * we gave some account of the initiation of a movement in the North of England, having for its object the establishment of a College of Physical Science in Newcastle-upon-Tyne. As the Executive Committee appointed at the public meeting had only then begun its work, the details entered upon were given as mere indications of the general form the institution might be expected to take. A letter from the Master of University College, Durham, which appeared in our columns more recently, added somewhat to our information, and a circular which has been issued, with commendable promptitude, by the Executive, is now before us, representing the views of the promoters as modified in committee.

We shall probably best further the intentions of the Committee, whom we are anxious to aid, and at the same time give our readers the most reliable information, if we reprint this document verbatim :

"It is proposed to found at Newcastle-upon-Tyne, in connection with the University of Durham, a College for the teaching of Physical Science, especially as applied to Engineering, Mining, Manufactures, and Agriculture.

"The want of such an Institution has long been felt in the North of England, and it is believed that while it would be useful in all the above pursuits, it would be of especial value to all persons intended for the professions of Mining and Engineering.

2.

"Such an Institution (which it appears desirable to limit at its commencement to purely scientific objects) would offer instruction in the following branches of scientific knowledge. 1. Pure and Applied Mathematics. Chemistry. 3. Experimental Philosophy. 4. Geology, Mineralogy, and Biology. Professorships and Lectureships will be founded on these subjects. It is proposed that the course of study shall last for two years, that it shall consist partly in attending lectures and partly in the work of the laboratories, that there shall be examinations at the end of each year, conducted mainly by Examiners from the Universities, and that at the final examination the successful students shall receive the title of Bachelor or Associate of Science of the University of Durham, or, upon certain further conditions, the degree of B.A. It is hoped that classes of evening lectures for those who are unable to attend during the day may soon be formed.

"The Government of the Institution will be entrusted to a Council, of which one-third will be nominated by the University of Durham. The University has offered the sum of 1,000l. annually towards the establishment of Professorships and of ten Scholarships of 201. each to assist students. It is believed that 2,000l. a-year is the lowest estimate at which it is possible to place the expenses of such a College, even at its commencement, and it is proposed to appeal to the public for a subscription to create a capital fund of at least 30,000/. If this amount be collected, the endowment from the University of Durham will be made a permanent one. When it is remembered that such an Institution will benefit a very large portion of the population of the Northern Counties, and be directly useful to nearly all branches of Manufacturing and Agricultural, as well as of Mining and Engineering pursuits, it is believed that no difficulty will be found in ultimately raising this sum, which, according to the experience of all similar institutions, will probably be increased by private donations both for Scholarships and Professor* See NATURE, vol. iii. p. 461. VOL. IV.

ships. It is proposed to offer Subscribers the option either of paying their whole subscription at once or of extending it over a period of five or six years. Small as well as large subscriptions are invited towards the abovementioned fund. Upwards of 100,000/. has been recently collected in a similar case, or is in the course of collection, in subscriptions ranging from 2,000l. to the very smallest sums."

The last paragraph pleases us most. Six years is perhaps long enough to look forward in arrangements of many sorts, but not in matters pertaining to finance. The adoption of a scheme such as that originally suggested, based on a preliminary terminable endowment, would have crippled the energies of the whole staff, by suggesting the possibility of the early demolition of the structure they were labouring to build. It can scarcely be known, until the trial is made, how much may have to be done in the way of creating the demand for scientific education in the locality. We do not for a moment doubt its existence to

a considerable extent, but we cannot suppose that the present case will form any exception to the general rule, that educational facilities are only slowly and by degrees taken advantage of by the classes for whose benefit they have been primarily designed. If the proposed college begins to find an appreciative public, and to promise eventual success within the six years, we should regard it as a subject of congratulation, and a proof alike of energy and judgment in its management, rather than as a matter of course. Happily, for this reason, the guarantee principle is to be put upon its best basis-funded property. Instead of 1,000l. per annum for a term of six years, as at first proposed, the public is asked for 30,000/. in one sum. This, with the consequent permanent endowment from Durham University, which may be regarded as equal to another 30,000l. capitalised, will provide a substantial foundation to commence upon. Nor can we doubt the wealthy men of the North. that the amount required will be easily raised amongst

We may perhaps say one word more about the selection of subjects for professorships, as our former remarks are alluded to in the Rev. Mr. Waite's letter.

We adverted to the absence of any mention of Biology as a part of the scheme of education in the report of the speech of the Dean of Durham at the preliminary meeting. In the revised programme, above reprinted, biology is not omitted, but that is all that can be said. The subject is tacked on to geology and mineralogy, and the result is a complete anomaly. To teach mineralogy in any modern sense, a man must be more than an average chemisthence no one who is not an expert in geology, mineralogy, chemistry, zoology, and botany, will have the requisite qualifications for the chair which it is now proposed to constitute. We trust that the Committee are prepared to pay pretty smartly for so handsome an instalment of omniscience. Our fear that biology of itself might be thought too large a subject for a single professorship, was at any rate groundless, but we doubt whether entire exclusion would be worse than the grant of a third of a chair.

The geological knowledge of first importance in a mining district is essentially "stratigraphical," in other words, that attained by practical field work. Just so much paleontology is necessary as will enable the student to recognise the more common characteristic fossils, and sufficient acquaintance with minerals to render him fami

C

The

liar with ordinary rock specimens. It would be better author of this work in a very creditable manner. that Geology of this sort should be associated with a sub-introductory chapters are condensed and clear, just giving ject like mining, instead of being placed in the position enough information on the general structure and economy it at present occupies. of insects to interest the uninitiated reader, and lead him on to the more detailed account of each order given in the succeeding chapters.

Mineralogy, in any right sense, is only applied chemistry, and would be more in place as a recognised portion of the chemical curriculum in such an Institution than as a part of geology. Few geologists pretend to mineralogy beyond a sufficient knowledge of the general external characters of rocks for the recognition of the commoner varieties. Palæontology, on the other hand, as a subject of systematic study, is but a phase of biology, and cannot without violence be linked with subjects arising out of the laws which govern the inorganic world.

In thus enlarging upon our former remarks, we are actuated solely by a desire for the success of an undertaking which has our entire sympathy.

Just as we are going to press we learn that it has been determined to push forward the arrangements so as to enable the College to open its doors in October. This is a wise decision on many grounds. The first week in October has become the recognised time for the commencement of winter courses of lectures, and delay beyond that might easily entail the loss of a whole year. Of the 30,000l. required, upwards of 17,000l. has already been subscribed, without any systematic canvass, and we can scarcely doubt that the remainder will be forthcoming. On public grounds we would venture earnestly to second the appeal made by the Committee, and to express the hope that the liberality of the coal-owners, manufacturers, and merchants of the district will enable them to open the Institution free from pecuniary embarrassment, and clear of the manifold difficulties that beset an undertaking burdened at the outset with debt. We also hear at the same moment that the Committee has again debated the question of a biological professorship. That body seems to be undecided as to whether it would be less ridiculous to ignore biology entirely, or to include it with a number of quite distinct branches of science in a sort of miscellaneous professorship, and the prevailing view now seems to be that, on the whole, the former alternative is the least conspicuously absurd. Surely there is a third course open to the Committee. We trust wiser counsels will prevail, and that we may never have to record that in Newcastle-the home of Bewick and Selby, Fryer and Alder, Winch and Robertson, not to name a host of living biologists—in the focus of the Tyneside Naturalists' Field Club-a College of Natural Science has been established in which Natural History in its higher aspects is excluded as a subject of study.

STAVELEY'S BRITISH INSECTS British Insects. A familiar Description of the Form, Structure, Habits, and Transformations of Insects. By E. F. Staveley, Author of " British Spiders." (London: L. Reeve and Co., 1871.)

To compose a work on so extensive and difficult a

subject as "British Insects," which shall convey a large amount of useful and interesting information without being too much overloaded with bare facts,-which shall be accurate without being dry, and amusing without being flippant,-is no easy task, yet it is accomplished by the

An excellent feature of the work is the clearness of the type, and the well-executed woodcuts which somewhat too sparingly illustrate the text, while sixteen coloured plates by Mr. Robinson contain admirably life-like portraits of nearly a hundred of our most conspicuous or most interesting insects. A few extracts will best illustrate the author's style. In the chapter on the larvæ of Lepidoptera it is remarked, that there is neither time nor place in which we may not find the traces of these creatures or the creatures themselves.

"If at one time of the year we tear a handful of moss from the trunk of a tree, out drop some little brown chrysalids; if at another we drag a tuft of grass up by the roots, there we find silken tubes, the homes of some small caterpillars. We find them in fungi, we find them in grain, we find them in teazle-heads, in fir-cones, in rosebuds, and in fruit; and the Hymenopterist, carefully watching the insect emerging from a gall, discovers that he has reared in it a moth! On the face of a lichencovered rock we see a moving fragment, and lo! a little caterpillar, neatly encased like a caddis-worm in a tent of lichen, is moving and feeding, safe even from the bird's sharp eye. We open our drawers, and there, oh, sight of horror! What is that streak of white silk upon the best garment-the garment laid by, too good for common wear? We look farther; what is that dusty little roll? It is a great-coat on a microscopic scale. It matches our best garment ominously. It moves-a head peeps out-some little legs, and away it walks !-tell not the housekeeper!— away it walks in safety from the admiring Entomologist.”

As an example of the woodcut illustrations we give the series showing the progressive stages in the transformations of the dragon-fly. The sluggish mud-coloured pupa ascends the stem of a grass or any other stalk of convenient size which rises above the surface of the water, after a time the skin cracks behind, between the wing cases, and the head and thorax of the enclosed fly are drawn out. The abdomen follows, the insect turning up and clinging to the pupa case, where it remains till the wings increase to the full size so rapidly that they can be seen to grow.

In the chapter on Diptera there are some good remarks on the many erroneous uses of the term "Fly."

name.

"Being a 'popular name' the people have a right to mean what they choose by it, and they avail themselves of the right-some meaning by it one thing, some another, some every flying insect for which they know no other Thus the 'fly' of the former is usually the little hopping turnip beetle; the 'fly' of the hop-grower is an aphis; the 'fly' of the herdsman a gad; while to the citizen almost anything to be seen with wings (except pigeons flies are flies, one fly the fly, the common well-known little and sparrows) is a fly. There are some, again, to whom black house-fly. Here at last is something definite. No, not even now; for these will, at least, claim their young housefly, and their full-grown house-fly, and expect you to believe that late in the year their house-fly takes to biting you, little dreaming that the little fly, and the big fly, and the fly which bites you, not only are different species but even belong to different genera; that the little fly never grows big, that the big fly never was little, and that their house-fly could not bite you if he would. What, then,

are we to understand by the name fly? It is clear that the popular sense has no sense at all, or too many senses, and yet the word cannot be spared from our vocabulary. In any Latin dictionary we shall find Musca (fly), and the entomologist pounces upon it and says it shall mean the tribe of two-winged insects. Linnæus so used it, and his genus Musca, now broken up into many new genera, represented the greater number of those insects which the entomologist now claims as flies."

In some parts of the work there is rather a tendency to jump at conclusions, and to give explanations of very doubtful value. It is attempted, for instance, to explain why the bee has four wings instead of two, by the fact that it is necessary for them to fold up and pack into a small compass to avoid injury and be out of the way during work, and this it is said is "the purpose of the division of the wing." This conveys the entirely erroneous

TRANSFORMATIONS OF THE DRAGON-FLY

impression that the wings of insects are normally two, and that the four are formed by the "division" of these two, an impression which we feel sure a person so well informed as the author could not have meant to convey. It also seems carrying hypothetical life-history a little too far to say of a bee emerging from the pupa that "into his mind rushed a full sense of his responsibilities," and on finding himself, say, a worker, "he, or rather she, be

came aware that the duties of house-builder, housekeeper, nurse, and even soldier and sentinel, devolved upon her;" and accordingly she forthwith "addressed herself to the task of repaying to futurity that debt which the cares of a former generation had laid upon her, and daily she toiled in its fulfilment." To make this exposition of the mental state of the newly-born bee complete, we should have been told whether it regulated its conduct in doubtful cases

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