SUBSCRIPTIONS FOR VOL. VI. See IMPORTANT NOTICE AREY NOW DUE. : ‘ v on page 160. F Wie |Zfa ey er ‘ New Series Vol. VI., No. OcT., 1899. vied ay ¥ SCIENCE: GOSSIP oy hy AN ILLUSTRATED MONTHLY RECOR Nature, Country Lore & Applied Science. EDITED BY JOHN T. CARRINGTON, ASSISTED BY F. WINSTONE. 3 LONDON; ae E-G Ir’ O Sere a W.C., AND PKIN Mans HALI AMILTON, KEN BERLIN: R. = PRICE SIXPENCE. ce ys eee SCIENCE-GOSSIP. WATSON & SONS’ NEW MICROSCOPES & APPARATUS. NEW EYE-PIECES. WATSON’S HOLOSCOPIC & s. d. For use with either Achromatic or Apochromatic Objectives, an adjustment being provided which enables them to be made either over or under cor- rected at once. Very finest performance. In four powers. Student’s pattern. Each .. = =e Ob 3 WATSON’S New Parachromatic Oil Immersion Con- denser, 1°30 N.A., aplanatic Aperture, 1°25 N.A., undoubtedly the best condenser yet produced for high-power work. Complete with Iris mount -- 610 0 Optical part only .. ea il seg es - 500 WES''S Table Stage, as described in ‘* Microscopy” column, Scrence-GossiP, June, 1899 .- ce ee ONL7/0G WATSON’S Van Heurck Microscope .. ce WATSON'S Edinburgh Student's Microscope -. WATSON'S ‘‘ Fram” Microscope Be Ac oe WATSON’S MICROSCOPES and other Scientific Instruments supplied on the PROGRESSIVE PAYMENT SYSTEM. Micro: Objects: & s. d, Anatomy of a Leaf (9 pieces), arranged on one slide .. 0 2 6 Section through entire Bud of Lily, showing ovary, anthers, petals, pollen grains, &c. .. 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A HERONRY “THE Cara Balkam is a shallow lake, varying in size, according to the season, from four to six miles long and two to four broad. It is overgrown with reeds and rushes, and is a hideous, pestilential place, reeking with malaria, alive with mosquitoes, swarming with leeches, unattractive in the extreme to any but a lover of birds. To him, if he escape an attack of fever, it is well-nigh a paradise, for wild fowl in immense numbers resort to it at all times of the year, its dense cover rendering them safe from \ Batkam. with incomplet Car of plain and tit General vier disturbance, and its surroundings suiting their varied requirements. On one side it is bounded by a vast plain, on another by salt marshes leading to the sea, while on the third and fourth sides, itis close to the mountains anda deep lake of considerable size. It was during the winter of 1875, I first visited this place in search of some birds ‘‘as big assheep,” which the natives told me were to be found there. These proved to be pelicans (Pe/ecanus onocrotalus), and [ still remember my excitement when I got within range ofa large flock of them, also my pride, as I waded through the black vile-smelling mud dragging the great creature out, for I was then young and new to the country. Later visits to the Cara Balkam gave me cranes, herons, egrets, swans, and spoonbills, as well as many species of ducks. In these excursions, how- ever, I never penetrated more than a hundred yards or so into the lake, but in spring of this year, being n the neighbourhood, I determined to reach its Oct., 1899.—No. 65. Vol. VI. IN F and leaves of bulrushes, [29 ASIA MINOR. PER.M.S centre, the real home of the birds. Starting early one morning in the last week of May, my wife and I, with a friend, reached the lake side before the forenoon was far advanced, and embarked in a couple of boats provided by some fishermen livelihood These men waded alongside, who gain a_ precarious from the river near by. dragging and pushing the boats, and we were soon ina dense growth of reeds and bulrushes, which to a height of rose The water lilies, of which there were two species, were beautiful. The eight or ten feet above our heads. numerous dragon flies, grey, steel blue, and bright scarlet, were flitting about in all directions, giving animation to the scene. In half-an-hour we reached a piece of open water about an acre in extent, and emerging from the cover of the reeds, we beheld such a sight as would delight the eyes of any naturalist. From the further side rose clouds of birds, hundreds round us, as though enquiring circling why we intruded on their domestic privacy. MMundreds more which circled round their nests, were so numerous ITeRONRY IN CARA BALKAM WitH NESTS OF SMALL EGRET and close together that we could proceed no further without destroying them, which we particularly wished to avoid. Nests were found which we believe belong to the large egret, they were composed of stalks fitted into a reeds, about a foot above water level, the clump of epgs bei of a bluish-green colour. The small egret (4rdea x zet/a), with eggs and nests similar to the last-named, but smaller. The squacco heron (1. va//ordes), eggs 130 SCIENCE-GOS STP. rather darker in colour and smaller than the small egrets. The night heron. A cormorant was very numerous, but the species could not be identified. The eggs were bluish-white, with encrustations of white lime. The glossy ibis (Aadcinellus zgneus) nests were like the egrets, composed of bulrushes, and placed at the same height above the water; their. eggs are bright blue. There were other species I could not identify whilst on the wing, and being the breeding season we did not wish to shoot any. Towards the borders of the lake we saw several species of ducks, many reedwarblers, the pied king- fisher, and on a low tree near to where we disembarked were a pair of white tailed eagles (Halzaetus allicella), which -flew off on our approach. Immediately beneath the branch on which they rested we found the neat nest of one of the Paridae, on the construction of which the two tits were busily at work, taking little notice of our presence. Its framework was composed of long grasses, filled in with the down of bulrushes. When complete these nests are of the shape of a chemist’s retort, and are generally found suspended to the outermost branches of willows overhanging a river. The eggs, five or six in number, are pure white, and usually laid early in May. The odours of the decaying vegetation under the hot sun were sickening, and interesting as our visit to this swamp-like lake had been, we were not sorry to leave the boats, and mounting our horses proceed on our journey to the more healthful lake hidden in the mountains of the east. Smyrna, oth June, 1S9Q- TRISH RIcANG INeAVinss: By JoHN EH. Barsour. ie popular magazines and papers one constantly sees references made to plants possessing names other than the usual English appellations. These names might be described as national, for they are only used locally, in one of the four sections of 3ritain. Many Welsh names of plants are so well- known as to be used continually, but generally in cases having reference to plants with some special interest in relation to Ireland, the Irish name is omitted, while the Welsh is given. Whether this is due to want of knowledge or access to works on the subject, I cannot say, but such a collection of names might prove useful, if published in a widely circulated magazine like ScreNcE-Gossip. I have therefore prepared a list of some of these, collected so far as. I have been able up to the present time. They are entirely belonging to the Phanerogams, and the majority of the names are’ from old sources, and I believe correct. Some plants haye one, others two or more Irish names, some include under one name more than one Species of the same family, and in a very few cases, I have not been able to identify the Irish name and that corresponding in English, with any family or species, as will be seen by the occasional notes made in the list. Clanabhar mona, Siodamona. Zy7ophorum vagi- natum. cotton grass. Biorrach Lachan. Spargantum simplex. reed grass. 3reallan, Raidhleadh. Lolium perenne. rye grass. Onnakes. Hordeum pratense. meadow-barley. Briumseau fiothran. 772¢¢cwm repens. couch grass. Leadan. Dipsacus sylvestris. teazle. Wrachalach. Greima diabhail. Scabzosa succisa. devil’s-bit scabious. Caba desan. Scabzosa arvensts. corn scabious. Cruach phadruig. Plantago major. greater plantain. Slan luo. Yantago lanceolata. rib-wort. Balath Enis, Cuchullon. Gadi verum. lady's. bed straw. Luso Garabh, = cannot be fully described in a short advertisement, All persons 7 7 adverts . YE 7 PU } interested in the classification of scientific data, especially those MODE OF PUBLICATION. commencing a research, are invited to send for a prospectus and Ist. In 36 Numbers—Published every Wednesday. Price fuller particulars to UOnwe Shilling net per Number, or post free ls. 2d. é A. RAMSAY, : ne SET in Weekly Numbers, £1 1G.. net. 4, Cowper Road, Acton, London, W : 2 a : ; - (a een errr a 2nd. In Four Volumes, handsomely bound in green cloth, THE STUDENT'S gilt top (each containing Seventy-Nine Coloured Plates), HANDBOOK of BRITISH MOSSES, CS ee ane Evatt By H. N. Dixon, M.A., F.L.S. The SET in Cloth Volumes, £2 8s. net. ith illustrations and keys to the Ge € Specie 3 By LG ys to-the Genera and Species, Srd. In Four Volumes, elegantly bound in halt morocco, > A EL a eae. as gilt top (each containing Seventy-Nine Coloured Plates), Author o, Mckee Guiae to British Mosses. P Fift Shilling Vol 609 pages, with Introductory Chapters, ctc., and 60 plates, See een Shillings net per Volume, or post free 8vo., cloth, Price, 18s. 6d. a : - 7 . JOHN WHELDON & c0., 38, Creat Queen Street, W.C. The SET in Half Morocco Volumes, £8 net. N.B.—Books on all Glasses of Natural History kept in stock. —_—— NOTE. er tn ce on the day ¢ Just Published. on pl INSECTS: ee 2) THEIR STRUCTURE AND LIFE. Subscriptions are received at all Booksellers’, or direct by A PRIMER OF ENTOMOLOCY. By GEORGE H. CARPENTER, B.Sc. (Lond.) FREDERICK WARNE mS (AO), Cloth Gilt, 4s. 6d. net. J.M. ENT &CO., Aldine House, Bedford Street, London, W.C. BEDFORD STREET, STRAND, W.C. ” iv SCIEN CE- GOSSIP. | STEVENS’ AUCTION ROOMS. SALE ANNOUNCEMENTS. Tuesday, Oct. 24.—A Collection of Natural History Specimens. SCIENTIFIC INSTRUMENTS INCLUDING ALL KINDS OF Photographic and Optical Apparatus, Electricals, Mathematical, Surgical, and Musical Instruments, and Miscellaneous Property of every description. _ EVERY RY FRIDAY. NATURAL HISTORY SPECIMENS ONCE_AND TWICE A MONTH. Mr. J. C. STEVENS Begs to call attention to the above Sales at his Great Rooms, 38, King Street, Covent Garden. Goods Received at any Time, and Included in these Sales. TANGENT GALVANOMETER, £1 10s. T, TAMBLYN-WATTS, Scientific Apparatus Maker, Goldielands, Settle, Yorks. Catalogue of Electrical Apparatus and Materials, 6d. post free. Catalogue of Balances and Weights, Apparatus. for the study of Mechanics, etc., 6d. post free. MISS FF. M. HELE, Warwick Lopcr, Uprer KNow Le, BRIsToL. Invites offers for her valuable collection of MINERALS, FOSSILS, SHELLS, &c., &c., As under, which she is prepared to dispose of to col- lectors or Public Museums, divided to-suit purchasers. Three Cabinets containing — Minerals, Fluors, Quartz, Agates and Precious Stones (including a valuable collection of Bristol Quartz on Iron and Quartz on Agate), Two Cabinets containing Devonian and Bristol— Madrepores (polished). A collection of— Foreign Marbles (polished). A large collection of— Paris Basin Fossils and Miocene. Three Cabinets of — Corals and Fossils, from every Formation. A complete collection of the following Shelis— Unionidz, European Helicidz, Do. Paludinidz, Do. Melanidz. Also a collection of— , Tropical Land Shells, and of Mediterranean Marine Shells. A fine collection of Polished Foreign Woods, Detailed particulars on Application. X-RAY APPARATUS. Of the Highest Quality and Finish only. As supplied by us to H.M. 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Climate: Bavic Condition. To be completed in 16 Numbers. Conpuctep By ALEXANDER RAMSAY. Prospectuses and Subscription Forms free by post on applica- tion to the Publishers. A few of Nos. 1 to 12 still in print, price 1s. each. The Geological Time Papers and Charts. No. 1. The “R™ Geological Time Scale, price 1d. Nos. 0 to 3 Charts, 3d. each. Post free, rd. e Now Ready. O'DRISCOLL, LENNOX & CO., Printers and Publishers, 10 & 12, Elephant Road, Elephant & Castle. Now Ready. London: SCIENCE-GOS STP. constitution as will cause percolating water to deposit any material that it holds in solution. I may safely state that in no case where it is in the remotest con- tingency possible to refer the manganese to ‘* Primary Viltration,” do we find this essential condition present. Indeed, the only cases in which we find an impervious bed beneath the seams, are those in which such seams oceur at the base of the gravel and the underlying deposit is clay. Such seanis of considerable thickness as a rule, and’ moreover extend over a considerable area. For instance, I recently traced one at the base of the High Terrace gravel of Acton for a distance of 250 yards. Such examples as this, clearly owe their position to ‘* Secondary Filtration.” (2.) Contemporaneous Fluviatile Deposition. Let us suppose that we havea river flowing through an area in which ores of manganese, preferably di-oxide, occur in some abundance. During the denudation of such an area, the manganese, as successive deposits of it are attacked, will be carried down in suspension or chemical solution by the river. As the manganese from the various deposits will have approximately the same specific gravity, it will have a tendency to collect in certain places. If the water becomes super- charged with the soluble mineral, or if chemical change takes place either through some alteration in the constitution of the bed of the river, or through some influx of other matter; then the manganese will be precipitated and will encrust the sedimentary material forming on the bottom. There are three reasons why precipitated manganese will not penetrate the sediment to any great extent. In the first place if the bottom is argillaceous, then such non-penetra- tion must obviously occur. When, however, the bed of the river is gravel or of similar porous material, some other reasons have to be found for the non- penetration. The chief, in such cases is that encrustation goes on almcst simultaneously with precipitation; and secondly, the mineral now rendered insoluble meets with the resistance of the water that saturates the gravel which forms the bottom. Adopting this theory we find that the field- evidence supports it in every respect. By it we can explain the occurrence of continuous seams in stiff impervious loams and clays, in gravels in which no impervious material underlies the manganese, and in which the seams of gravel so stained are not different from the other beds in their constitution or porosity, or if they are more impervious, essentially owe this character to the presence of the manganese. Furthermore, we can explain by it how the overlying and underlying beds are entirely unaffected by these seams, which would not be the case in the majority of instances, if filtration produced them. There is one more point to which it is necessary to refer. Where is the source from which the manganese was derived? We, have in the Thames valley no manganese bearing strata other than the drift, or, at least, no deposit capable of supplying the quantity found in the drift. In the discussion following my are I 137 paper, before alluded to, Mr. A. E. Salter, I.G.S., said that it was just possible that Wales was the parent source, The recent physiographical researches of Prof. Davis and Messrs. Buckman and White, have tended to show that the Thames once flowed from Wales across what is now the Severn valley. If this be the case, then we have a source for our manganese, and at present [ can only adopt Mr. Salter’s view. At all events, in the light of our present knowledge, it is impossible to offer a better one. In conclusion, our difficulties in this respect are enhanced because of the fact that we cannot base too much reliance, if any at all, on the manganese being in the position in which it was first deposited, after its derivation from the parent strata. clo J. C. Graham, 2, Garden Court, Temple, London, E.C. CROMWELL ROAD MUSEUM. “THE collections in the Natural History Museum at South Kensington have lately been enriched by specimens obtained by various exploring expe- ditions. The zoological branch benefited greatly by the expedition to Sokotra, which was organised by Mr. W. KR. Ogilvie-Grant, representing the British Museum, and Dr. H. O. Forbes, director of the Liverpool Museum, under the auspices of the Royal Geographical Societies and the British Association. The lepidoptera obtained are specially numerous some of the species being hitherto unrecorded. Kight new species of reptiles, twenty species of marine fish, large collection of shells and insects, and many other fauna were obtained. Another expedition that has yielded results of considerable interest to the geological and zoological sections is the one from which Dr. J. W. Gregory, of the geological Department, has just returned. His object was to examine the geology of Antigua. Some acquisitions of particular interest were obtained by means of the expedition sent out by the Hon. Walter Rothschild to the Galapagos Archipelago off the Coast of Ecuador. Amongst others was a fine example of the rapidly diminishing gigantic land tortoises, also a series of five hundred birds, anda large collection of reptiles. Mr. Welt Blundell and Lord Lovat have presented to the trustees the fine series of birds made by them during their recent adventurous journey in Abyssinia. The collection, consisting of 530 specimens of 234 species, has not yet been thoroughly examined, but the ornithologists of the Museum are convinced it is of the greatest interest. Since the departure of the mission dispatched to Sierra Leone by the Liverpool School of Tropical Diseases, for the investigation of malaria, hundreds of mosquitoes have been sent to the British Museum from every part of the British Empire, and it seems probable the museum will soon be in possession of an unique collection of the genus Cuv/er. Mr. E. Austen, the dipterologist of the Museum, is a member of Major Ross’ party, and will endeavour as far as possible to make collections of other groups. 3 = Oo (e) SCIENCE-GOS STP. BRITISH FRESHWATER MITES. By CHARLES D. Soar, F.R.M.S. (Continued from page 103.) 2. Hygrobates reticulatus Kramer, 1879. [EP PAEALE, —Biadhy : Amateurs. Photography PATENTED. A combined Cinematograph and Snap- THE BIOKAM PRQJ ECTOR, , Printer, Projector For Projecting, Reversing and Enlarging, fitted with sar Camera, P ; J ; ; One VOICTLANDER Wide Angle LENS and adapted to screw into Lens Flange of ANY EXISTING LANTERN. Reverser and Enlarger, fitted with two SPECIAL VOIGTLANDER LENSES. HIGHLY FINISHED IN POLISHED EBONY. PRICE £6 6s. Finished in Polished Mahogany. Size 2 x 3 x 5}. Weight 16 oz PRICE £4 4s. Positive and Negative Films, perforated (length 25 ft.), Size 3 X 54 X Oo}. Weight 2} Ibs. price 3s. 6d. each. : - Biokam Film Subjects (length 25 ft.) price 10s. each. 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Set CC. 41.—Collection of 13 Common Rock-forming 4 Minerals in box, forelementaryclasses 0 7 6 Set CC. 42.—16 Specimens to show Rock Structure, &c., in box .. Z 010 6 Set CC. 43.—20 various Types eG Camamen Rocks : Igneous, Metamorphic and pares, for elementary classes : po ak) ol’ 0) Set CC. 44,—20 Supplementary Rocks .. 1 10 20 Supplementary Minerals 015 0 Set CC. 45.—60 Typical Fossils in box .. : aoe OMO Set CC. 46.—12 Microscopic Slides, illustrating Physiographic Geology, for ele- ; mentary classes 012 6 Set CC. 47.—12 Microscopic Slides of Typical Rocks, for elementary classes 018 0 Set CC. 48.—Coal Mining.—zo specimens. —Wrsaies of Coal, of Rocks and of Fossils found in the Coal Measures 016 0 Set CC. 49.—MVetalliferous Mining.—z0 specimens of the commoner ores of metals, and of the minerals associated with them.. 1 1 O k= See Editorial Notice, January No. of *‘ SciENCE-GossIP,” and WAC SO Sade Cosehagee post free. COX & Co., 99 & 101, NEW OXFORD ST., LONDON (And through all Educational Houses). MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM. THE LABORATORY, PLYMOUTH. The following Animals can always be supplied either living or preserved by the best methods :— Sycon ; Clava, Obelia, Sertularia ; Actinia, Tealia, Caryophyllia, Alcyonium; Hormiphoria (preserved); Leptoplana; Lineus, Amphiporus; Nereis Aphrodite, Arenicola, Lanice, Terebella; Lepas, Balanus, Gammarus, Ligia, Mysis, Nebalia, Carcinus ; Patella, Buccinum, Eledone, Pecten ; Bugula, Crisia, Perdicellina ; Holothuria, Asterias, Echinus ; Ascidia, Salpa (preserved), Scyllium, Raia, etc., etc. For Prices and more detailed Lists apply to The Director, Biological Laboratory, Plymouth. W. LONGLEY, EIN IHO SOONG CABINET and APPARATUS MAKER, 12, WHITE HART STREET, Catherine Street, Strand, London, W.C. 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(2 series). 24 Scales and Skins of Reptiles and Fishes. 5 Series of 24 Miscellaneous Non-botanical Objects, 2s.each. 12 Series of 24 Miscellaneous Botanical Objects, &c., &c. CLEANED UNMOUNTED SECTIONS OF HORNS, DIATOMS. HOOFS, &c. Series Xxvi.—qs. per 12 tubes. Series xlvi.—18 Objects, 2s. Pleurosigma acuminatum. Horn of Goat. Pensacola Bay. By) Buffalo. Navicula veneta. o Ox. Abashiri (Japan). ” Rhinoceros. Hanover. Hoof of Horse. Port de Nice (France), &c. i“ Bison, &c. W. WEST, 26, Woodville Terrace, BRADFORD. Send Stamp for List of 76 different Series. THE MARINE DIATOMACEA DE FRANCE. Including all the British Species and those of Countries in Europe. By MM. H. & M. PERAGALLO. The first part (RAPHIDIEAY) is just out. 50 Plates with 1,124 species and vars. described, and 240 pages of Text. Price £2 (post free). N.B.—The subscription to the complete work is 4 up to the end of 1899, after which date it will be raised to £5 until completion. Send Remittance and orders to J. TEMPERE, Micrographe et Publisher, 168, Rue St-Antoine, PARIS. MICROSCOPICAL. For the benefit of avzatezrs who find difficulty in obtain- ing good objects at a moderate rate, I offer first-class slides, including insects, rare _ crystals, foraminifera, &c., at cost price (3d. each). Material, lists, and information free. Dealers 7zo¢ supplied. Frauk P. Smith, 15, Cloudesley Place, Islington, London, N. TO EGG COLLECTORS. blanks and complete series Gentlemen wishing to fill should write to— W. F. H. ROSENBERG, F.Z.S., 48a, Charing Cross Road, London, W.C. ILLUSTRATED CATALOGUE OF APPARATUS, Post FREE. The ‘‘Desideratum” combination Price and Label List of British Birds’ Eggs, in handy book form, price 3d., gummed qd., refunded on subsequent purchases. A large selection of British and Exotic Birds’ Eggs kept in stock. BIRKBECK BANK SOUTHAMPTON BUILDINGS, CHANCERY LANE, W.C. TWO-AND-A-HALF per Cent. INTEREST allowed on Deposits, repayable ondemand. ‘1 WO per Cent.on CURRENT ACCOUNTS on the minimum monthly balances, when not drawn below £100. STOCKS and SHARES purchased and sold. SAVINGS DEPARTMENT. For the encouragement of Thrift the Bank receives small sums on deposit, and allows Interest monthly on each completed £1. BIRKBECK BUILDING SOCIETY. How to PURCHASE A HOUSE for Two Guineas per Month. BIRKBECK FREEHOLD LAND SOCIETY. How to Purchase a PLOT OF LAND for 5s, per Month. The BIRKBECK ALMANACK, with full particulars, post free. ESTABLISHED 1851. FRANCIS RAVENSCROFT, Wanager. SCIENCE-GOSSTP. bears some superficial resemblance in the imago state. The palpi, however, are shorter than in Z/a? , and the antennae longer. The expanse of the wings is somewhat greater, the fw. more triangular in shape, and with an extra nervule not foundin 7#ars. Hew. more «listinctly caudate. ? with an abdominal pouch as in /arnassius. 1. L. puziloi Ersch. 54 § Bright ochreous yellow, ¢ 60, mm. lighter. F.w. with long and short bands of deep black starting from the costa, h.w. with a sub-marginal row of black lunules with blue centres, with basal and costal black dashes, and a bright carmine blotch near an. ang. U.s. paler, especially h.w. which have the cent. area nearly white, the outer third of wings is occupied by a triple band f red, blue and yellow, at an. ang. a blue spot. Luchdorfia pusilof, upper and under sides. Antennae black, and head, thorax and abdomen black with yellowish hairs longer than in 7%aés. The pattern of thef. w. recalls that of Pzpiliv alexanoz and /.. That of the like the podalirius. h.w. is pattern of 7azs ; in fact, its external appearance is an index to the composite character of this interesting and beautiful species. ITAg., Amur (Wlad., Ask., Baran., Suif.) IV. V. LARVA on -1sa7 = um (R. and H.), ? rst THALS ¥. s having the head and eyes of GENUS 4. Middle-sized butterflie moderate size, palpi straight, passing beyond the head Clubs of antennae curved. Wings opaque but some- times with a small transparent patch on fore wings. All the known species have black spots on costa of H.w. and sometimes caudate at ou. marg. generally with a sub-marginal row of red and black Spots. The ground fw. dentated and often subcaudate, colour of the wings is yellow, varying trom whitist deep orange ochre. The larvae are cylindrical, rather short with spines, which *t at the extremity Y-shaped proce They feed on we se tubercular elevations. \ small posterior to the head. Various spe ol 1 WSL lo hia. This small but beautiful generic group is confined, except in the case of one species, to the immediate neighbourhood of the Mediterranean, on the I uropean, Asiatic, and African sides. There are erisyl, Hh y the forms that three distinctly marked types, and 7. formerly accounted varieties LV Xena, runina, some of were of these, seem to deserve specific rank, which will be here accorded. The species that collectors are 7. of France, and in Canton Tessin in Switzerland, also 7. medesicaste, S.W. and Species, occurring in Minor. 7. & e? is found in the neighbourhood of the Sea of Marmora, and 7. Western Caucasus and Armenia. The well-marked are most easily found by British folyxena, which occurs in the South which is common in many places in S.E. France. 7. cerisyt is an eastern Bulgaria, Greece, and Asia aucasica in the and very beautiful aberration of 7. medesicaste named honoratit is absolutely confined to the neighbourhood of Digne in the Basses Alpes. It is strange that its area should be so limited, and I cannot help thinking that it may some day be found in other localities in the same part. of France. Up to the time of my now wniting, how- ever, it has only been taken in the locality abov indicated where a few Specimens are found eve season, chiefly by the native collectors, who send them to the dealers, by whom they are offered for sale at about £2 each. It is to be obtained by collecting large numbers of the larvae of 7. medesicaste and rearing them on the chance of obtaining var. onoratt?, but I do not think that this wholesale method is to be commended, as it is likely to lead to the extermination of the species in the particular locality in which honoratii therto occurred. For my own part, during tw visits to Digne I found 72 medesi far fr n comm and only saw one specimen of Aonoratit. Fi great numbers of the larvae must feed in inaccess > places, yet it should bear minated by is very desirable that entum in mind that Aoxoratiz might over collecting. 146 SCIENCE-GOS STP. The species of this genus must be looked for in the early part of the year, nowhere later than June. 7 rujina appears as early as January in Algeria, and a few stragglers of 7. medestcaste may be seen at the end of June in S. France, though April and May are the most usual months. 1. T.cerisyi, B. Lg. B. E., p. 9, pl. IL, fig. 2. 58—62 mm. é wings very pale yellow, black at base. The fore wings with 5 black costal spots, apex with a blackish band, internal to this a short interrupted band of same colour. H.w. with one red costal spot anda sub-marginal row of the same colour, external to these some black spots, vezy rarely, with indistinct blue centres ; ou. marg. strongly dentate, with one tail. ? generally somewhat larger than ¢. Ground colour more ochreous yellow, pattern more strongly marked, central area of h.w. with two rows of black dashes, the lower ones extending to inner marg. Iiead, antennae and thorax black, abdomen black with reddish orange lateral stripes. U.s. lighter, especially h.w., which are white with central spots marked with greenish. Has., rocky places and mountain passes in Bulgaria, Greece, Turkey, Asia Minor, and Palestine. I., II., and VI. Larva, greyish black, with yellow dorsal and lateral spots. On __—— > - SCIENCE-GOSSIP. 157 MICROSCOPY FOR BEGINNERS. water immersion of 97° and an oil immersion of 52° By F. Sninuincron Scares, P.R.M.S, ( Continued from page 125.) Iv will have been noticed that the stands we have mentioned are quoted with an inch and a } inch or } inch objective. It generally pays to make the whole purchase at once, as the makers charge a little less in such cases than if the items are bought separately. Tt may be as well to state that the terms 1 inch, finch, etc., do not represent the distance between the under side of the lens and the object. The tendency of the day is to increase the aperture, bringing the lenses closer and closer to the object, and the designations ’ referred to may be taken practically as representing approximate magnifying power. Taking the inch as a standard, we may say that without any eyepiece it gives in a 10 inch tube a magnifying power of approximately 10 diameters. A + inch gives 40 ‘diameters, a } inch 60 diameters, a 2 inch 5 diameters, and soon. To get the actual magnifica- tion one must know the magnifying power also of the eyepiece, and the length of tube. If the eyepiece magnifies 6 times, then an inch objective with this eyepiece and a 10 inch tube, will give a total magnification of 60 diameters ; a } inch will magnify 240 diameters, and soon. With a 6 inch tube the magnification will be only jy of the foregoing, and this must be borne in mind. Opticians have a tendency, however, to give rather larger magnifi- cations than those we have mentioned, owing to the difficulty of making low power objectives of as wide aperture as the taste of the day demands, and this should be noted when purchasing. The higher the aperture the better should be the definition, but the higher also is the price, and there is the additional disadvantage to many workers, that anything out of the exact plane in focus is practically invisible. Most workers use objectives of both high and low aperture and each have their advantages. Theoretically objectives should have .26 N.A. for each 100 diameters of combined magnification, but in practice very much less than this suffices. Messrs. Beck for instance make most of their objectives of comparatively low aperture, not only because they are less expensive, but because they give more of what is known as ‘‘penetration,” or the power of seeing more than lies in the one actual plane. Moreover a high aperture reduces the working distance. The tendency of the day, however, is to insist on high apertures, and each maker tries to outdo his competitors in this respect. Our advice to beginners is to be content with moderate apertures, at any rate at first, but, above all, to get objectives made by first-rate houses only. If of other than English make see that the screw is of the “* society ” gauge. We had perhaps better say a word or two here on the subject of Numerical Aperture, or, as it is generally written, N.A. For a full discussion of the Abbé theory of microscopic vision and the use of immersion lenses we must refer the reader to the standard text-books, such as ‘‘ Carpenter on the Microscope.” If the reader will, how- ever, bear in mind the well-known law of physical optics, 7.2., that rays of light passing, from a denser medium into a rarer one are refracted /rom the perpendicular and ace versd, he will understand that terms representing ‘‘ angular aperture,” or the cone of light embraced by the objective in am, could not be used to represent the aperture of lenses that had a drop of liquid of high refractive index, stich as water or oil, between them and the coverglass. In fact a are each equivalent to an air lens of 180°. Accord- ingly a formula has been universally adopted by which 1 N.A. represents an angle of 180° in air, which is rather higher than any air lens can grasp in practice, and in estimating the numerical aperture of Bite cognizance is taken not only of the angle of aperture of the objective but also of the refractive index of the medium in which it is designed to work, whether air, oil, or water. The formula is, multiply the sine of half the angle of aperture by the refractive index of the medium. Therefore, according to this formula, 1 N.A. will represent a corresponding angle of 97° in water and 82° in oil. The maximum theoretical angle for water is 1.33 N.A. For oil of the same refractive index as a crown glass cover it is 1.52. With special immersion medium and glass, Messrs. Zeiss have made a lens with an aperture of no less than 1.6 N.A., but it is of course proportionately costly and ean only be used for special work. Before leaving the subject of objectives we must touch briefly on what are called their ‘* corrections.” An objective at the present time is a very complicated _ affair. It is composed of two or more lenses of certain carefully calculated.and definite curves, set at equally definite distances. Most of the individual single lenses that go to make up the combination are made of two different glasses, such as crown glass and flint glass, joined together, in which the curves of the one correct certain aberrations in the other. These aberrations are of two sorts, ‘‘ spherical aberration,” or the non-coincidence of the marginal and central light rays in the objective, causing a curved field, and *“chromatic aberration,” or the non-coincidence of the colours that the lens, acting as the prism of a spectroscope acts, has fanned out and failed accurately to re-focus and combine again. This leads to outstanding colour, and though no achromatics are quite free from this fault it should be only perceptible on critical tests. A portion of the outstanding colour is got rid of by means of the diaphragm, which cuts off the ill-corrected marginal rays. Now, we need scarcely say that an objective that has been corrected for air cannot satisfactorily be used as an immersion lens, and zce versa, but it may be necessary to point out that an objective is likewise corrected for a certain length of tube and can- not be used critically for any other length of tube. This, whilst showing the advantage of having a draw-tube that will enable either short or long tube objectives to be used at will, shows also the limitations of variation of magnification by the simple device of drawing out or closing up the draw-tube. There seems to be an increasing tendency amongst English opticians of repute to correct their objectives for the short or continental tube length. This we regret for many reasons, one of which is that an objective corrected for the 1o inch tube performs better on a 6 inch tube, if necessary, than in the reverse case. And we especially protest against the practice of certain makers of quoting their objectives as giving certain magnificationswith a roinch wube, but refraining from adding the necessary qualification, that the said objectives are in reality corrected for the 6 inch tube only. Further, objectives are corrected for a certain uniform thickness of coverglass, though there is, wn- fortunately, no uniformity amongst opticians in this respect, and any alteration in either tube-length or coverglass thickness upsets these corrections. Of course, this is only noticeable with what is called a “critical image,” which the eye needs educating to perceive. (To be continued ). 1 ! Ts SCIENCE-GOSSTP. | OLOGY (GZS le Ne CONDUCTED BY EDWARD A. MARTIN, IF.G.S. SECTIONS ON THE BRIGHTON LINE.—A_ geo- logical section well worth visiting just now, is that which has been exposed in cutting the new line from Croydon to Red Hill, through the North Downs. Where the line emerges from the new tunnel at Merstham, the deep cutting that has been made can be viewed from the bridge which carries the road from Merstham Church over the railway. At the side of the road, running east and west, impure sandstone layers may be observed resting horizontally. These as seen down the cutting, north and south, dip at a considerable angle, and finally pass beneath the chalk at the mouth of the tunnel. The material quarried from the cutting has been carried south to form the embankment between Metstham and Red Hill. In some places masses of Gault Clay, in others Chalk have been thrown down, and on exposure to weathering, have split up into thin laminae. By this means, blocks of tough chalk can be opened with but little assistance from the hammer, and occasional fossils found. Nearer Red Hill, the Lower Greensand series has been cut into, and the rise in the ground which usually betokens the outcrop of these strata, is here visible. .The new rails will apparently be-=* carried through this formation in a short tunnel. CuRRENT BeDbING.—There is much that can be learnt in elucidation of geological problems by watching the action of the sea as it eddies around piles of piers or the ends of breakwaters at the sea- side. The way in which the sand is carried down by little streams, emerging from pools that have been left by the retiring tide, is pregnant with lessons to the physical geologist. I remember watching such action going on by the side of a groyne at Kemptown, Brighton. The tide had retired, and the water, which was still issuing from beneath the gravel on to the wide stretch of sand, made a miniature river, and hurried along the side of the groyne. At a certain point it reached a huge boss of wood, that was imbedded in the sand, and whose upper end was fixed in the wooden groyne by way of support thereto. In passing round this huge trunk, the velocity of the stream appeared to have been checked, perhaps in the first place by the fact that the trunk projected above the sand, and caused the energy of the stream to be lost in carving a new and more sinuous passage around it. The result showed itself by 2 deposition of the sand which had heen held in suspension by the stream, and the stream then passing on, fell over the miniature fall made by the projecting. boss. Another result then showed itself. The ferce of the fall caused a pit to be excavated at its base, which gradually deepened, and increased the amount of the fall. As fresh material was brought down by the stream, it was pushed over the shallow edge of the trunk of wood, and then slid down, at an angle of about 30 degrees, a declivity formed of ever-thickening strata. Here, then, was an example of the manner in which “current-bedding” is formed. All the little stratula of sand were pointing the same way, that is, away from the source of the current. They would all be wedge-shaped, the points of the wedges being deter- mined down the declivity at the furthest point to which the sand travelled at each fall. The sand was. prevented from accumulating in the hollowed-out pit, by the fall of the water.—Zdward A. Martin. SPRIAE AS EVIDENCE OF IcE-ACTION.—The old theory that striae upon rocks show, without any other support, evidence of ice-action, has received various shocks during recent years, and it is not now safe to rely too much .upon such markings as proof of glacier action. I have recently noticed similar mark- ings on loose, wet sand, alter it has just been left by the receding tide. Standing on the rocks facing a sea-wall. and between two breakwaters, I noticed that the sand stood very much higher against the eastern groyne than against that to the west of me. Each powerful wave that came in and ascended the sand swept over and across the shelving bank, and returned to the sea in a direction almost at right angles to that of its incoming. The result was a series of fine groovings, like striae, and under certain circumstances it can be imagined that these might be rendered permanent.— Zaward A. Martin. A PLEA FoR PiecEs.—It is not given to every collector to obtain the best specimens. These, as a rule, fall only to the hammer of the professional geologist. Those who can only devote their Saturday afternoons to study in the field, or are otherwise limited in the time they can spend on the subject, have frequently to be content with incomplete speci- mens. Many practised geologists look scornfully upon such as these, but there is really a good deal to be said on their behalf. When one considers the building-up of reptiles and mammals which has resulted from a few fragmentary bones, jaws and teeth, or incomplete casts artificially obtained in the case of the pliocene Lenham Beds ; the leaf fragments that have served in the cases of the Boyey Tracey and the Bournemouth Beds, it is unwise to cast aside the unsymmetrical and fragmentary, because at first sight they may appear to be valueless. There is, besides, the advantage in testing the knowledge and acumen of the student by these, when complete specimens would present no difficulty. a ee > —_ DucKWEEDS IN Essex.--A friend and I were botanising at Danbury in Essex last August, and on examining a pond we found that it contained three species of duckweed, viz., Lemna minor L, L. polyrrhisa L., and 1. gibsa L. This last is a rare and local species, but easily recognised by its tumid cells underneath the leaves. —Adwin £. Turner, Cogyeshall, Essex. FAscIareED Oreutb.-- As Mr. Cooper states (an/e, p- 91) that he found what was to him the first fasciated specimen of an orchid. I presume that he means a British species. It may interest him to know that I found a specimen of £frpacé?s having a bifurcated spike forming a fork some halfway up the inflore- scence, both stems being clothed with flowers in the usual manner. It was growing by the side of a road adjoining the undergrowth of a wood, and had made its way through a heap of road-scrapings.—Zdwix E. Turner, Coggeshall, Essex. LEERSIA ARYZOIDES, UNUSUAL ForM.—I send you a specimen of European cut-grass, that appears to have developed an unusual growth. In various botanical manuals the British form of this plant is said to have the panicle included partially within the sheath of the last leaf. This is, I am aware, the form generally found in Britain. The example enclosed is one of some gathered within the last few days at Amberley Wildbrooks, West Sussex. You will note that the panicle has grown more than two inches clear of the last leaf. Possibly this is due to the recent hot weather. —7/omas Hilton, 16, Kensington Place, Brighton, 25th August, 1899. BLAck-VEINED WHITE BUTTERFLY. —Although many of the present generation of lepidopterologists are inclined to imagine that fora crataegé is prac- tically extinct in Britain; such is byno means the case. I have it on excellent authority that this interesting butterfly is common in a limited district in East Kent, where last summer, hundreds might have heen taken, Several specimens were submitted in confirmation, out of a couple of dozen that were taken and set. They occur in fruit orchards and gardens. We have an inyitation to visit the locality next season, when we hope to report further on this butterfly. —/ohn 7. Carringion. TWISTING oF LeEprporpTreROUS Pupa.—I have been watching the curious twisting habit of some pupae of butterflies belong ng to the genus / avessa, and note that they do not appear to be capable of effecting this motion until about thirty-six hours after becoming pupae. They seem to lose the power again about forty-eight hours before emergence. I presume they possess the twisting motion to dislodve insects, especially ichneumon flies, and various predatory enemies. I have seen a caterpillar which had crawled on toa J azessa pupa not only dislodged but actually thrown some distance by the vigour of this twisting motion. Many lepicdopterous larvae possess this habit, but few to the same extent as some of the Vanessidae which, hanging head downwards by the apex of the last segment, twist round and round with remarkable rapidity.—A’. /. Hughes, Norman Court, Southsea, September 17, 189¢. SCIENCE-GOSSIP. 159 AN EARLY MEAL.—A cutious, to me unexplain- able incident came under my notice a year or two since, when clearing a bush infested by gooseberry caterpillars. Suddenly in the warm sunshine I found a specimen of green sawfly, which had, apparently, but just isstied from its chrysalis case,.as it was ina most soft and pulpy condition, almost transparent. and with its wings still unexpanded and crumpled. Yet, upon preparing this seemingly helpless creature for the microscope, I was surprised to find that its stomach and intestines were filled with the remains of an insect or insects, the chitinous portions being as hard and as sharp in outline as they would have been in a living state. The softer portions nearest the exit were, however, fully digested, those about midway partly so, the remainder, as already mentioned, filling up the space between the partially digested and the oesophagus. How did a creature apparently so help- less and unprotected contrive to capture and devour the fly or beetle, which had evidently been invested ina chitinous integument? It is highly improbable that the fly had gnawn its way out of its case and swallowed a portion of the cocoon, indeed the con- tents of the stomach clearly indicate that they belonged to an insect, and not 1o a mere structureless case. Perhaps some keen observer of these hymenopterous flies, may be able to afford mean explanation of the curious circumstance. The ehject I consider one of the most remarkable in my cabinet.—Zdward H. Robertson, Wooduille, Greenhouse Lane, Painswick, Glos’. : Habits oF COMMON Mantis.—In a work by Miss L. N. Badenoch recently published, she describes the habits of the common mantis. I should like to mention two points in which the Australian species seems to differ from that described by Miss L. N. Badenoch. I have watched large numbers of these insects, for long periods. In all instances when a mantis saw a fly within easy distance, it would commence to sway itself gently from side to side, and so swaying would gradually move to within striking distance. Then stop perfectly stilland remains so for a few seconds. Having carefully measured the distance, it rapidly darts out both forelegs, grasping the fiy round the head with one leg and over the wings with the other. Miss Badenoch says that it only darts out one leg, and that the fly is crushed between shank and thigh My observations do not confirm her observation by any means. I have never seen a fly crushed when caught by a mantis. As to the mode of eating the fly, I have always seen them commence to feed on the body at the junction of the head with the thorax. The head is quickly severed and the mantis eats down into the centre of the body. Miss Badenoch says that the body is torn into pieces and devoured ina moment. This has never happened in any I have observed. —/yank MW. Littler, Launcesten Tasmania, June 18¢9. VIPER AND GRASS SNAKE FRATERNIZING.—Some time ago, while gathering vioiets on a hill near Bath, I observed a curious association of snakes, which I should hardly have believed had I not myself made the observation. A common grass snake and a viper were lying together intertwined, the coils looking as one snake, excepting for their difference in pattern. They were basking in the sun, and I watched them for some time, but on being disturbed they uncoiled and disappeared among some bushes. —A. 2. Burr, Bath. ALBINISM IN FLOWERS.—I can add another rare plant to the list of white varieties of inflorescence. In a wood about five miles north of Bath, I found a fine plant of Daphne Mezereum with white flowers which, I believe, is a rare form.--41. 2. Burr, Bath. 160 CORRESPONDENCE, Ar the suggestion of several correspondents we open with this volume a department in which our readers may address the Editor in letter form. We have pleasure in inviting any who desire to raise discussions on scientific subjects, to address their letters to the Editor, at 110, Strand, London, W.C. Our only restriction will be, in case the correspondence exceeds the bounds of courtesy; which we trust is a matter of great improbability. These letters may be anonymous. In that case they must be accompanied by the full name and address of the writer, not for publication, but as an earnest of good faith. The Editor does not hold himself responsible for the opinions of the correspondents.—Zd. S.-G. SciENCE APPOINTMENTS. To the Editor of SCTENCE-GOSSTP. S1r,—-In answer to the question raised under this heading in your correspondence column, I may say that the smallness of the number of openings alluded to in your July number, is ever before the younger biologists. In some notes which I put together, I went so far as to discuss the prospects before one of these enthusiasts and with the exception of additional work in connection with the Science and Art Department, and a few schools, which I have included, my list differs but little from that given by your correspondent, I think however that there is rather too much fetish worship about the way in which the B.Sc. degree is looked upon. It simply shows that its possessor, having the necessary ability and luck, has been able to sacrifice a considerable amount of time upon the altar of an unknown god, while others have not reached the shrine. Experience is still lacking and a London B.Sc. certificate is no proof of originality or culture. There is no influence of the past or present behind it that may be looked for in the case of a degree, taken at a teaching university like Oxford. Nobody should know better the need for adaptation to circumstances in the struggle for existence than the naturalist, and although your second correspondent has found it necessary to fall back upon other know- ledge for a time, yet, considering how the various brandes of the broad subject, of biology may be turned to advantage, it may be possible for a man to stick to the science of his choice, and earna living at the same time. If there are more appointments on the other subjects, there are also more candidates. That itis harder work than reading for examinations, is the experience of, Yours faithfully, BIOLOGIST. TRANSACTIONS OF SocreTIES.—In consequence of pressure en our space, notices of transactions of Societies have been lately omitted, these will again appear next month, and Hon. Secretaries are invited to send them as usual, but only to include notes of general interest. [Ep. S.-G.] NOTICES OF SOCIETIES. Ordinary meetings are marked +, excursions persons following excursions are of Conductors. Illustrations. Nortu Lonpon Naturat History Society. Oct. 5.—+tPocket Box, Microscope and Lantern Ex- hibition. , 7.-—*Kew Gardens. L. B. Prout. 19.—+tNotes and Echoes. F. W. Frost. 00 21.—*Cycle run to Coopersale, Essex. YorKSHIRE NATuRALISTS’ UNION. Oct. —t+Annual Meeting at Harrogate. NorrinGHAamM NarurRAL ScreENCE RAMBLING CLUB. Oct. ; james of ¢ Lantern Norru Kenr 4.—t+Breathing Organs. 0 7.—"Field Ramble. 18.—}Microscopic Wonders trom Ponds and Ditches. W. Brown. HTon. Sec., Rosemount, 80, Church Lane, Old Charlton. C. Dy SCIENCE-GOSSTP. IMPORTANT NOTICE, The Proprietor of ScrENCE-GossiP having decided to manage the business department from indepen- dent offices at 110, Strand, London, W.C., all subscriptions, advertisements and payment for ad- verlisements must in future be sent to that address, and no longer to the Nassau Press, which latterly managed the commercial department for the pro- prietor. SUBSCRIPTIONS (6s. 6d.) for Vol. VI. are now due. The postage of SCIENCE-GossIP is really one penny, but only half that rate is charged to subscribers. NOTICES TO CORRESPONDENTS. To CORRESPONDENTS AND EXCHANGERS.—SCIENCE-GossIP is published on the 25th of each month. All notes or other communications should reach us not later than the 18th of the month for insertion in the following number. No com- munications can be inserted or noticed without full name and address of writer. Notices of changes of address admitted free. 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Tue Editor will be pleased to answer questions and name specimens through the Correspondence column of the maga- zine. Specimens, in good condition, of not more than three species to be sent at one time, cav7vage paid. Duplicates only to be sent, which will not be returned, unless accom- panied by return postage, and then at owner's risk. The specimens must have identifying numbers attached, together with locality, date, and particulars of capture. Tue Editor is not responsible for, unused MSS., neither can he undertake to return them, unless accompanied with stamps for return postage. EXCHANGES. Norice.—Exchanges extending to thirty words (including name and address) admitted free, but additional words must be prepaid at the rate of threepence for every seven words or less. British Dracon Fries. Wanted all species of British Dragon flies, state name if possible, and condition. Name requirements.—H. D. Gower, 55, Benson Road, Croydon. Four Cornish Chough’s eggs offered for books.—T. Stock, Frome Hill, Radstock, Bath. Vertico Mouliasiana (British) Borus popelaisianus, Strophocheilus sangod, and Str. bitaniatus from Pem, for rare foreign Helicidae.—J. W. Horsley, S. Peter's Rectory, Walworth, S.E. “Wantep living foreign spiders, larvae of Eumeta moddermansia, and locusts in exchange for macro-lepidoptera, fossils. ete.’—Fredk. Bridgman, ‘ Kenmore,’ Avenue Road, Crouch End, N. Diatom slides in exchange for other objects, or books on Microscopy.—H. Platt, Priory Villa, Victoria Road North, Southsea. OFFERED, V. soulinsiana, etc. Wanted, I. minutissima, S. oblonga, H. revelata, L. involuta, and other rare shells.— Fred Taylor, 38, Landseer Street, Oldham. WanTeED in exchange for about Seventy Old English and Foreign Coins, a Modern Bee Hive and accessories or some foreign Postage Stamps.—J. Sugden, ** Ryarsh,” Kingston Crescent, Portsmouth. ‘ OrrereED. Duplicate Foreign Postage Stamps. Wanted Foreign Marine Shells or Stamps notin collection of 2,000.— Jas. S. Wood, Wood's Buildings, Waller Gate, Neweastle- on-Tyne. FossILes, minerals, shells, plants, ¢tc.. offered in exchange for others.—Monsieur P. Rousseau, La Mazurie, par Aizenay, Vendée, France. SCIENCE-GOSSIP, ix WATKINS & DONCASTER, Naturalists and Manufacturers of Entomological Apparatus and Cabinets, N.B.—For Excellence and Superiority of Cabinets and Apparatus, references are permitted to distinguished atrons and Colleges, &e. Plain Ring Nets, Wire or Cane, including stick, ts. 3d., a8., 28. 6d. Folding Nets, 3s. 6d. and 4s. Umbrella Nets (self-acting), 78. Pocket Boxes, 6d.; corked both sides, 9d., 18. and 1s, 6d. Zinc Relaxing Boxes, od., 18., 18. 6d., and as. Nested Chip Boxes, 4 dozen 8d., 18. od. gross. Entomological Pins, mixed, 1s. 6d. oz. Sugaring Lanterns, as. 6d. to 10s. 6d. Sugaring Tin, with brush, 15. 6d., 2s. Sugaring Mixture, ready for use, 1s. 9d. per tin. Mite Destroyer (not dangerous to use), 1s. 6d. per lb. Store Boxes, with Camphor Cells, as. 6d., 48., 58. and 6s. Ditto, Book Pattern, 8s. 6d., 9s, 6d., and ros. 6d. Setting Boards, flat or oval, 1 in., 6d.; 1} in., 8d.; rJin., 9d.; 2 in., rod. ; a}in., 1s.; gin., 1s. ad.; ghin., 1s. 4d.; 4in., 1s. 6d.; ghin., us. 8d.; 5in., 1s. rod. Complete set of 14 boards, 10s. 6d. Setting Houses, 9s. 6d. and 11s. 6d., with corked back, 14s. Zinc Larva Boxes, od., 15. Brass Chloroform Bottle, 2s. Breeding cage, as. 6d., 48., 58., and 7s. 6d. | Catalogue (66 pp. ) sent post free on application. Taxidermist’s Companion, #.¢., a pocket leather case, containiag most useful instruments for skinning, 108. 6d. Scalpels, 1s. 3d.; Label Lists of Birds’ Eggs, 3d., 4d., 6d. Scissors, per pair, 28. Setting Needles, 3d. and 6d. per box. Coleopterist’s Collecting Bottle, with tube, 1s. 6d., 18. 8d. Botanical Cases, japanned double tin, 1s. 6d., as. gd., 5. 6d., 48. 64. Botanical Paper, 1s. 1d., 15, 4d., 18. 9d., a8. ad. perquire. [7s. 6d. Insect Cases, imitation mahogany, as. 6d. to 115. Cement for replacing Antennz, 6d. per bottle. Forceps for removing insects, 1s. 6d., as., as. 6d. per pair. Cabinet Cork, 7 by 3}, best quality, 1s. 4d. per dozen sheets. Pupa Diggers, in leather sheath, 1s. 9d. Insect Lens, 1s. to 8s. Glass Top and Glass Bottomed Boxes, from 1s. 4d. per dozen. Label Lists of British Butterflies, 2d. Ditto Land and Fresh-Water Shells, ad. Egg Drills, 2d., 3d., 1s.,; Metal Blow Pipe, 4d. and 6d. Our new Label List of British Macro-Lepidoptera, with Latin and English Names, 1s. 6d. Our new Catalogue of British Lepidop- tera, every species numbered, rs. ; or on one side for Labels, 2s. All Articles enumerated are kept in stock and can be sent immediately on receipt of order. The ‘DIXON’? LAMP NET (invaluable for taking Moths of Street Lamps without climbing the lamp posts), 2s. 6d. CABINETS. Special Show Room. The following are the prices of a few of the smaller sizes ; for measurements and larger sizes see catalogue. Insect. Eggs. Plants, Fossils, &c. 4 Drawers 138. 6d. ta8.0d. .... 108. © Drawers .....- 178. 6d. 16s. 6d. 158. od, A LARGE STOCK Minerals and Dried OF INSECTS’ Minerals and Dried Insect. Eggs. Plants, Fossils, &c. Syrawerbledeaesss) GAGs. ms cease G08: saacede. 258. yo Drawers ..--..-. 458 ........ Res Antoctcs 453. AND BIRDS’ EGGS. d Birds, Mammals, &c., Preserved and Mounted by First-class Workmen. 36, STRAND, W.C. (Five Doors from Charing Cross). THe Automatic CyYcLosTYLe. THE LATEST IMPROVEMENT IN DUPLICATING APPARATUS. FURTHER IMPROVEMENTS JUST MADE. Editor of ** SCIENCE-GOSSIP,” says: MAY, ’98, No.) “We can well recommend this Machine to Secretaries of Scientific for preparing documents.” AA peter. and with 6, complete for Send for full (illustrated) Particulars post free. Societies and manifold copies of notices or other For printing Reports, Specifications, Price Lists, &c., it is invaluable and soon repays its cost. With Complete Outfit for Reproducing Bandwriting Octavo size, £3 10s. 5 Quarto size, £4 15s. 5 Foolscap size, 5. Extras for Reproducing Typewriting : Octavo size, lIOs. Gd. j Quarto size, IIs. Gd. 5 Foolscap size, I2s. Gd. 3 Fitted with Unmeltable Rollers for Hot Climates, £1 Is. extra, any size up to Foolscap. To those requiring a cheaper process, less easy of manipulation, the following is suitable :-— The ‘‘Neo-Cyclostyle Hand-Roller Process. Prices from 25s. Unmeltable Rollers for Hot Climates supplied at an extra cost. others POL DL LOLL LE LOL LPL THE CYGLOSTYLE 60., °2S%°% == oS —————a eS Fis Wie ak a oa a. = igs sctentceicosste JOHN J. GRIFFIN & SONS, - Chemical, Philosophical, and Phot ooraphic nAteete Makers. MAKERS TO THE ADMIRALTY, WAR DEPARTMENT, INDIA & COLONIAL GOVERNMENTS- PHYSICAL AND GHEMICAL APPARATUS OF EVERY DESCRIPTION. HOLLOWAY’S PATENT GAS FURNACE WITH GRIFFIN’S RADIAL BURNER. Most Powerful and Reliable. NO BELLOWS! NO GAUZES! NO SMOKE! CHEMICAL NEWS, , September 23, 1808, p. 157 >— ‘Suitable for all the ordinary work of a laboratory, 28 various improv ements in its construction also greatly facilitating the work done with it. This Furnace, in addition to its cheapness, possesses several advantages over other aevethasiiax abe gas furnaces, The body is separate from the base, which extends forward, and forms a convenient stand for hot crucibles, etc., and for the furnace doors. The material of which it is made is such that although, like all internally-fired gas HEIHEISSS: it will crack, the crack is usually a Sele one, which can be readily closed up if desired, with fireclay. Full particulars of above, or complete General Catalogue, on Faginennsn 20-26, SARDINIA STREET, Lincoln’s Inn Fields, LONDON, W.C. JAMES J: HICKS, 8,9, & 10, Hatton GaRDeN, LONDON, SCIENTIFIC INSTRUMENT MAKER TO THE WAR OFFICE, INDIA OFFICE, ADMIRALTY, ae IS SOLE-MAKER OF THE NEW PATENT “WATKIN 7? MOUNTAIN ANEROID BAROMETER. THE only Aneroid that can be thrown in and out of action as required, and which, when out of action, is absolutely impervious to the influence of variations in atmospheric pres- sure. Trayellers and Surveyors*will now be able to ascertain co77ec? altitudes owing to the marvellous accuracy of this Instrument, which is described atlength by Mr. Wi HYMPER, the distinguished Alpine climber, in the “ Times’ of December 17, 1 o ff} It is made in Aluminium fon lightness, in SOLE MAKER s/s} either 3-inch or 4}inch sizes, with Sling AMIENS V4g7 Leather Case. PRICES: Scale to Scale to 5,000 feet .. £5 5S. 15,000 feet .. £5: 15S. 10,000 ,, .. £5 10S. 20,000 ,, .. £6 OS. HICKS’S famous Student’s MICROSCOPE (Right-hand Illustration) With A Eyepiece, Double Mirror, Brass Slipping Stage, Sliding Draw Tube 2 in. long, 1 Objective dividing }, } and x inch, Coarse and Fine Adjustment, Live Cage, Forceps and Condenser, in neat Mahogany Cabinet, with lock and key. Price, £3 15s. Od. MAKER of all kinds of Standard Barometers and Thermometers. * Tttustrated Price Lists FREE on Application. Lonpon : Printed by the Borotpu Press, Lititep, Sweédiand Court, Bishopsgate Streét, and Middlesex Street, E.C. °-~