WANTED, specimens of British bees; will give in exchange Lepidoptera, Coleoptera or Diptera (the latter well set on cards, but unnamed).-A. E. J. Carter, 9 Argyle Crescent, Portobello, N.B.

WANTED, birds' nests and eggs from all parts of the world; British specimens offered in exchange.-J. T. T. Reed, Ryhope, Sunderland.

SCIENCE-GOSSIP for Sept. 1881 to March 1882: ditto for June 1885 to Dec. 1885; "Out of Doors," by Rev. J. G. Wood; "Manual of Injurious Insects," by Miss Ormerod; and "Practical Biology," by Huxley, in exchange for Shuckard's "British Bees," Darwin's "Cross- and Self-fertilization of Plants," or specimens of Coleoptera and Hymenoptera.A. E. J. Carter, 9 Argyle Crescent, Portobello, N.B.

WANTED, Rocking, Roy's or other good microtomes; will give large quantity of first-class slides for them.-Fred. Lee Carter, Gosforth.

WANTED, mounted or unmounted parasites; will give others in exchange-160 to select from. Send lists.-Fred. Lee Carter, 25 Lansdowne Terrace, Gosforth, Newcastle-on-Tyne.

WANTED, a good microscope and accessories, in exchange for a collection, in album, of about 1200 foreign stamps in perfect condition; catalogue value, 11.-P., 80 Leathwaite Road, Clapham Cominon, London, S. W.

GooD object for the polariscope-horn, bone, whalebone, chemical crystals, &c., also micro photographs; good exchange in slides. Write first.-J. Boggush, Alton, Hants.

WANTED, good dissecting microscope; offered, well-mounted slides of rare objects, collection of echinoderms or other zoological objects.-Charlotte Sinel, Peel Villas, Jersey.

MICRO SLI ES.-A series of fern slides and others in exchange for first-class micro and magic lantern slides.-Walter Henshall, The Hollies, Bredbury, near Stockport.

FOR exchange:-SCIENCE GOSSIP for 1884, with eleven coloured plates; what offers ?-John T. Foster, Little Driffield, East Yorkshire.

WANTED, live or dead specimens of Vitrina pellucida and varieties; exchange given in freshwater shells.-W. E. Collinge, Springfield Place, Leeds.

IN exchange for well-mounted micro slides, bound or unbound vols. of SCIENCE-GOSSIP, a polished mahogany box to hold 104 microscopic slides.-Herbert Spencer, Masboro' House, Balham, S.W.

A QUANTITY of well-mounted and interesting slides, and land and freshwater shells, Desiderata, Newman's "British Moths and Butterflies," Cooke's "Ponds and Ditches," and books on Coleoptera, pond life and micro natural history.James C. Blackshaw, 4 Ranelagh Road, Wolverhampton.

WANTED, foreign shells and corals, in exchange for fossils, books or cash.-J. W. E., 145 Milnrow Road, Rochdale.

BRITISH and Australian marine zoophytes wanted.-J. W. E., 145 Milnrow Road, Rochdale.

SCIENCE-GOSSIP complete for first twenty years, bound in double volumes, nearly new; also large number of good microscopical slides, animal and vegetable-what offers ?-Micro, 10 Belmont, Bath.

MOUILLEFARINE, 46 rue Sainte-Annes, Paris, wishes to do extensive changes with a botanist of the New World; offers references.-Ch. Copineau, juge, Tribunal civil de Doullens (Somme).

"TOMLINSON'S Cyclopædia of useful Arts, &c." (Virtue), 9 vols., cloth, numerous fine steel plates, &c.; also "Knowledge," Nos. 1-56, in thirteen monthly parts, as published, both clean and good, exchanged; -plate photo lens or magic lantern preferred.-Hughes, Assistant Overseer, Bangor, N. Wales.

WANTED, named and localised English land, marine and freshwater shells, or foreign ditto; exchange fossils, coins, &c. -F. Stanley, Margate.

WANTED, named British or foreign birds' eggs, or preserved skins; exchange coins, meda's, fossils or shells.-F. Stanley, Margate.

Rotifera.-Wanted, a few correspondents for occasional exchanges. David Bryce, 37 Brooke Road, Stoke Newington Common, N.

WANTED, Continental, American and foreign plants and micro-fungi, in exchange for indigenous (British) species. Correspondence with students of foreign micro-fungi invited.-Rev. Hilderic Friend, F.L.S., Carlisle.

LEPIDOPTERA.-Duplicates: Sambucata, Tiliaria, Comitata, Megacephala, Ruberata, Rhomboidaria, Phragmitidis, Iota, Umbratica, S. Ligustri (1). Desiderata: numerous.-George Balding, Ruby Street, Wisbech.

FOR exchange, Planorbis glaber, etc., for other shells.-John Clegg, 5 Derby Street, Millwood, Todmorden.

FOR exchange, Plan. dilatatus and glaber exchanged for other land and freshwater shells.-S. Clough, 20 Abingdon Street, Blackpool.

GOOD carboniferous fossils offered for other fossils, micro slides, or electrical apparatus.-J. A. Hargreaves, Charlestown, Shipley, Yorkshire.

Morpho cypris, Morpho menelaus, Morpho aga, the most dazzlingly beautiful of exotic lepidoptera; what offers ?Joseph Anderson, jun., Alre Villa, Chichester.

"Knowledge," in parts, 4 vols.; what offers ?-Joseph Anderson, jun., Alre Vilia, Chichester.

OFFERED, first-rate slides of marine algæ, illustrating structure and reproductive organs; many species. Wanted, Kützing's "Species Algarum," and other works on algæ.-T. H. Buffham, Comely Bank Road, Walthamstow.

FOR exchange, Helix sericea, Helix hortensis, var. olivacea. Wanted, Limnea glutinosa, Limnea involuta, Helix lamellata, Helix pomatia, all vars. of Helix aspersa, except minor; all vars. of Helix caperata, Bulimus acutus and its vars., and vars. albina of Pupa umbilicata and Pupa marginata, and many others.-A. Hartley, 15 Croft Street, Idle, near Bradford.

WHAT offers for the following?-6 vols. of Lardner's "Science and Art:" 2 vols. "Handbook of British Fungi," by M. C. Cooke, M.A.; 2 vols. “Food and its Adulteration," by Hassall; I vol. "Materia Medica;" "How to Work with the Microscope," by Beale; 'Mounting Microscopic Object," by Davis; a microscope preferred.-J. H. Morgan, St. Arvans, Chepstow, Mon.

FOSSILS from all formations desired in exchange for other fossils from li s, magnesian limestone, &c.-John Hawell, M.A., Ingleby-Greenhow Vicarage, Northallerton.

AMMONITES and belemnites desired in exchange for fossils, minerals, shells, &c.-John Hawell, M.A., Ingleby-Greenhow Vicarage, Northallerton.

BERG-MEAL, or mountain-meal, from Norway, slides, and a small quantity of material, both prepared and unprepared, in exchange; good diatoms preferred. Send lists.-Rev. A. C. Smith, 3 Park Crescent, Brighton.

OFFERED, complete clutches, with full data, of dipper, magpie, long-eared owl, tawny owl, black grouse, re grouse, snipe, curlew, kittiwake and others. Wanted, over a hundred species of British eggs, in clutches, many of them not uncominon.-B. A., Clifton House, Uxbridge.

A LOT of land, freshwater, and marine shells to name; would any of your readers name these for me (true name required), and in return would send two of each species, if possible, for their trouble?-John Jos. Holstead, 19 Millholme Terrace, Upperby Road, Carlisle.

WANTED, Isocardia cor and other British shells; exchange Cardium aculeatum and a variety of other kinds of marine and freshwater shells.-Mrs. Heitland, The Priory, Shrewsbury.

BOOKS, ETC., RECEIVED.

"A Flora of Hertfordshire," by the late A. R. Pryor (London: Gurney & Jackson). "Mineralogy," by Frank Rutley, third ed. (London: Thos. Murby).-" Elementary Text-book of Physiography," by W. Mawer (London: J. Marshall & Co.). "Report of the U. S. Commission of Fish and Fisheries for 1885" (Washington: Government Printing Offices)." British Frogs and Toads," by Linnæus Greening." Botanical Record Club, Rept. for 1884, 1885, 1886."-" Trans. Royal Soc. U. S. Wales."-" Journal of Conchology."-" Book Chat."-" Scribner's Monthly."-"The Amateur Photographer."-"The Garner."-"The Naturalist."-"The Botanical Gazette."Journal of the New York Microscopical Society."-" Belgravia."-" The Gentleman's Magazine."-" American Monthly Microscopical Journal."-" The Essex Naturalist."-"The Midland Naturalist."-"Feuilles des Jeunes Naturalistes.""The American Naturalist."-" Journal of Microscopy and Nat. Sci"-"Scientific News.""Wesley Naturalist. "Naturalists' Monthly."-" La Science Illustrée."-"Junior Review, Science, Lit. & Art."

COMMUNICATIONS RECEIVED UP TO THE 13TH ULT. FROM: A. G. T.-W. B. G.-W. R. W.-P. B.-C. R.-I. S.J. T. T. R.-T. H.-J. G.-G. K. G.-F. H. A.-A. H.T. H. B.-J. A., jun.-J. A. H.-W. T. P.-J. C.-G. B.— J. H.-J. H.-A. C. S.-Rev. H. F.-B. A. C.-J. J. H.-H. -S. C.-H. B.-F. S.-D. B.-H. O. H.-W. W.-J. H. G. J. W. E.-G. E. E., jun.-J. E. B.-J. W.-B.-F. L. C.— W. H.-W. E. C.-R. T.-C. R.-W. J.-J. T. F.-P. K.C. D.-F. L.-W. E. W.-C. L.-I. B.-R. F. G.-W. E. W. -C. J. W.-M. A. B.-F. R. F.-Z. W.-A. G. H.— G. E. E., jun.-E. W.-N. L.-&c.

S regards the avifauna of the Colorado region, the Mexican and American element is much more in the ascendant, and up to the present I have only observed four which are specifically identical with those in the British list, and of these Agelaus phaniceus and Ceryle alcyon, are only occasional and certainly not native in Britain, while Pica rustica is represented by the variety Hudsonica only, and Anas boscas alone is quite identical with a native British bird.

At present I have only two Colorado crustacea on record, and of these Gammarus robustus is allied to our English G. pulex.

The Arachnida have not yet been worked out, but they have a decidedly European stamp, and most belong to English genera; the same may be said of the Myriapoda, the genera Julus, Lithobius and Geophilus having abundant species closely allied to their British representatives.

The Coleoptera, with certain conspicuous exceptions, are very like the British species, such genera as Amara, Bembidium, Cicindela, Pterostichus, Coccinella, Aphodius, &c., being well represented, while a Poderus, very like littoralis, is common in certain districts, and I have found European-looking species of Meloë and Quedius.

Many of the Hymenoptera are peculiar, yet there No. 279.-MARCH 1888.

are species of Bombus, Vespa, Odynerus, Chrysis, &c., resembling British forms.

The Neuroptera are to a great extent European in general character.

The Lepidoptera are also many of them of European type, an Alucita resembling polydactyla (hexadactyla) is frequent on windows, and many other European genera abound. Of the sixty Rhopalocera I have on record, as inhabiting Colorado, only two, Vanessa antiopa and Danaïs plexippus, have been taken in England, and we know the last to be a recent introduction, but forty-nine belong to British genera, and Pieris oleracea represents P. napi, modified by changed conditions, as does Vanessa milbertii, V. urtica, and several others are closely allied to European species.

The Diptera are similarly for the most part of British genera, Tabanus, Tipula, Lucilia, and Muxa being abundant, and among the Hemiptera we find representatives of such genera as Leptocoris, Lygous, Miris, Calocoris, Notonecta, Corixa, Cimex, Cicada (5 species) and Jassus.

The only two leeches I have note of belong to the genera Aulostomum and Clepsine; earthworms (Lumbricus) are rare, I am told that a few exist in Wet Mountain Valley, but I have not been able to secure an example.

The flowering plants of Colorado have been ably described by Dr. J. M. Coulter, and present many features of interest.

In the Ranunculaceae al! the genera are British, as well as the following species:-Myosurus minimus, Ranunculus flammula (represented by var. reptans), R. sceleratus, and R. trichophyllus. The only species of Papaver is P. nudicaule. Among the Cruciferæ are Draba incana, var. confusa, Cardamine hirsuta, Erysimum cheiranthoides, Nasturtium palustre, N. officinale (but this is an introduction, it has been found near Denver, and I found it on Saguache Creek, above Rock Cliff), Camelina sativa, and Lepidium

D

sativum. The seven species of Viola include V. palustris and I. canina, var. sylvestris. Cerastium alpinum (var. behringianum) and C. arvense occur, as well as Arenaria verna. Hypericum, so prominent in England, is represented by only a single species, II. scouleri. Astragalus is a huge genus, with fortysix species, including alpinus and hypoglottis. Fragaria vesca is abundant. Six species of Saxifraga, hirculus, cæspitosa, cernua, rivularis, stellaris (var. comosa), and nivalis are also British (Saxifraga is an essentially boreal genus. Lieut. Greely found S. rivularis (var. hyperborea), S. cernua, S. oppositifolia, S. nivalis, and S. caspitosa in the Arctic region of Grinnel Land). The six species of Epilobium include angustifolium, alpinum, and palustre (var. lineare). E. angustifolium is excessively abundant; on Sept. 5th, I passed through a burnt-up spruce-forest on Pottery Pass, between Wheeler and Red Cliff, and the charred trunks no longer shading the ground, a dense growth of this species had sprung up, together with species of Aster, &c., completely covering the soil. Adoxa moschatellina is found, and Linnæa borealis and Galium boreale (this last I found on the Grand Mesa, at an elevation of about 8900 feet). Erigeron is a large genus, and includes E. acris.

*

Senecio has 16 species, but none are British; the genus is probably boreal, but the species are unstable, and soon vary under new conditions. Hieracium, a large English genus, has only three species and a variety in Colorado; but H. umbellatum is given as "from Lake Superior to the Rocky Mountains.” Taraxacum officinale has the varieties alpinum and scopulorum, and I found an ordinary-looking dandelion by Swift Creek, Custer Co. The three species of Primula are farinosa, parryi, and angustifolia. Parryi I found abundant on the Sangre de Cristo Range. Gentiana is represented by ten species-as might be expected of such a typically Alpine genus. Polemonium has four species, including cæruleum. Myosotis sylvatica appears as the var. alpestris, a forget-me-not of the most vivid blue, which I found growing in little compact bunches on the top of the Sangre de Cristo Range on August 4th, right above timber line, with Parnassius (near to Apollo) and an Alpine Colias to keep it company. Chenopodium hybridum, glaucum and rubrum are found-I picked the last near Surface Creek, Delta Co. Polygonum has several species, but the only two British ones, P. aviculare (Pikeview, El Paso Co., July 13th) and P. convolvulus (Salida, Chaffee Co., Oct. 19th), are probably not indigenous. Humulus lupulus is common. The only species of Orchid common to Britain are Corallorhiza innata and Spiranthes romanzoviana (this last an example of the migration of boreal species into Ireland). The Juncaceae include Luzula campestris and spicata, and Juncus filiformis,

*This pass has no name on the map; we named it so, because we found some fragments of ancient pottery and a stone arrow-head there.

triglumis, castaneus, and tenuis var. congestus. The three Naiadaceæ are Zannichellia palustris, Potamogeton rufescens (a Middlesex and Surrey 'plant) and P. marinus var. occidentalis. The representatives of Scirpus are caspitosus, lacustris var. occidentalis, and sylvaticus var. digynus. Carex has forty-nine species, mostly European, or allied thereto, and includes C. pyrenaica, rupestris, capillaris, ampullacea, vulgaris, atrata, alpina, muricata, fætida, vulpinoïdea, disticha, echinata, &c. The Gramineæ are to some extent peculiar, but the list includes Alopecurus alpinus, Calamagrostis stricta, Festuca ovina, &c. The twentytwo Pteridophyta have the following common to Britain :-Isoětes lacustris (var. paupercula), Lycopo dium annotinum, Botrychium lunaria (and also the doubtfully British B. lanceolatum), Asplenium septentrionale, Phegopteris dryopteris, Lastræa filix-mas (var. incisa, Mett.) Equisetum pratense and E. variegatum. The fungi have not yet been worked out, but there is no doubt that most of the species are also European. I have myself found Agaricus (Psaliota) campestris in more than one locality. Cases of poisoning, supposed to be due to Ergot (Claviceps purpurea) are reported by Professor Wm. Trelease.

Farther north, the evidences of the boreal fauna and flora become even more apparent. I was much interested in examining the collection of the Entomological Society of Ontario, Canada,* and noticed therein specimens of the following British species from the immediate neighbourhood of London, Ontario-Syritta pipiens, Apis mellifica, Metrocampa margaritata, Ennomos alniaria, Euplexia lucipara, Noctua plecta, N. c-nigrum, Agrotis saucia, Chelonia caia (var.), Nomophila noctuella (this a migratory species), Galleria cereana, Eupithecia absynthiata, Vanessa antiopa, V. cardui (this species is said to have occurred in millions in some parts of Canada in 1885), Danaïs plexippus, Ptinus fur, and Chrysomela (Gastrophysa) polygoni. It is very probable that some of these species were introduced by human agency, but some are doubtless boreal. One feature in the collection was the presence of no less than twelve species of Plusia, none of them British. In the extreme north, where all the species are boreal, the proportion of species common to Europe becomes overwhelming. Greely gives a list of species found on the expedition to Grinnel Land; of the nine birds eight are British, and of the twenty-five floweringplants, sixteen belong to British species. His list of Cryptogamia also includes Equisetum variegatum, E. arvense, Barbula alpina and Cladonia rangiferina.

So much for the boreal fauna and flora of Britain. I will not now deal with the Eastern and Western groups, nor the Asiatic distribution of certain species. As regards Africa, it may be said that the portion south of the Sahara has no relation to the British fauna, and, perhaps with a few exceptions, all the

Exhibited at the Colonial Exhibition, South Kensington.

British species found in Africa, south of the Sahara, are either migratory or were imported by human agency. Certain European Lepidoptera are conspicuous in all African collections, and these I regard as belonging to the migratory group *-such are Acherontia atropos (from Natal to Gambia and Kilimanjaro), Sterrha sacraria (Kilimanjaro), Charocampa nerii (Natal and Gambia), and the following species in a collection from Gambia—Deiopeia pulchella, Heliothis peltigera, Plusia ni, Cherocampa celerio (a species wandering even to New Caledonia), Sphinx convolvuli, and Lycana Bætica.

T. D. A. CoCKERELL.

West Cliff, Custer Co., Colorado.

A CHAPTER ON BENZOYLSULPHONICIONIDE, OR SACCHARINE.

By DR. ALFRED CRESPI.

UCH is the somewhat uncouth and unfamiliar name that will soon be known to every one. It is the scientific designation of that singular sweetening agent which, though known to scientific men for some little time, came prominently before the public in the presidential address of Sir Henry Roscoe, at Manchester, six months ago. Such a name ought to cover properties quite out of the common run, and when we inform the reader that saccharine-the name it will popularly be known by -is 250, or, it may be, 300 times as sweetening as cane sugar, his curiosity will be aroused.

Unfortunately, the medical and scientific papers often contain reports, framed in all fairness and goodwill, of marvellous discoveries in electricity, chemistry, agriculture, and medicine, that it is confidently promised will revolutionise modern life; and while we remain on the qui vive, looking out for more information, and hoping soon to profit by the discovery proclaimed in such warm terms, we wait in vain, and the world goes on in its humdrum way much as usual, neither the better nor the worse for the march of scientific discovery.

It is reassuring to be told that saccharine will not drive cane and beetroot sugar from the field, for those familiar objects of daily use there will still continue some demand; but it will be useful in culinary operations, and as medicine, and as a flavouring agent, and perhaps in other ways.

Its sweetening properties are remarkable. One grain of the ammoniacal hypo-sulphite of silver will render 32,000 grains of water distinctly sweet; but one grain of saccharine, according to Professor Stutzer, of Bonn, will sweeten 70,000 grains of

water.

* Vide "Entomologist's Monthly Magazine," March, 1885,

p. 233.

Saccharine is one of the many derivatives of coaltar, and was very fairly described by Sir Henry Roscoe, in a lecture at the Royal Institution, as "the most remarkable of all the marvellous products of the coal-tar industry." Now when all is remembered that coal-tar has done for mankind in the shape of providing colours, essences, and flavours, in the past thirty years, this is strong praise.

Saccharine is a white amorphous powder, and when examined under the microscope, is found to have a crystalline appearance. It melts, or fuses, rather, at a temperature of 424° Fahr., and then undergoes partial decomposition, while it gives off a powerful and easily recognisable odour. Placed upon the tongue, in its pure state, it is rather disappointing, as its sweetness is less marked than one would expect. Two explanations offer themselves in the first place, it is not, in its pure state (nor will even the saliva thoroughly dissolve it) highly soluble in water; and in the second, its strength is so great that it deadens, by its very intensity, the nerves of taste, much in the same way as when we enter a brilliantly-lighted room, on a dark night, we are dazzled from the pupil being widely dilated, or, better still, much as a beam of electric light falling from a short distance upon the retina causes confusion of vision and dizziness.

Saccharine must, therefore, be regarded as an essence, as par excellence the concentration of sweetness, and to get its full power needs free and intelligent dilution. Vanellin, another of the many wonderful products of coal-tar, which is rapidly displacing the older and better-known vegetable flavour vanilla, is also overpoweringly pungent, and far pleasanter in a less concentrated form. In cold water saccharine is hardly at all soluble, and although it is more soluble in warm water, it is not till it is mixed with boiling water that it becomes very soluble. The completeness of the solubility is greatly increased by neutralising the fluid in which it is placed, and this can be done most readily by adding carbonate of soda or carbonate of potash, two sufficiently familiar articles in most well-to-do households. Saccharine expels the carbonic acid present in the solution, and soda or potash salts of saccharine are formed that taste almost as sweet as pure saccharine itself. Probably for commercial and domestic purposes saccharine will soon come into common use in the form of an alkaline powder. Messrs. Burroughs, Wellcome & Co. sent us some tabloids containing half a grain of saccharine, and equivalent roughly to a large lump of loaf sugar. We find that it is better to put the tabloid in the cup, and then pour in hot tea, coffee, or cocoa, and after stirring a few times, adding the milk or cream. The flavour is in no way peculiar, but scarcely as agreeable as sugar, though use would soon remove that little objection.

cane

Alcohol, that powerful solvent of many alkaloids

and strong chemical agents, takes up saccharine freely. One gallon of a 40 per cent. mixture of alcohol and water will hold 1391.6 grains; a gallon of So per cent. alcohol takes up 2250 ̊5, while absolute alcohol-that is to say, alcohol perfectly free of any admixture of water-only takes up 21189 grains. This great solubility of saccharine in alcohol will be of much service to manufacturers of pure British wines, liqueurs, cordials, and essences. In practice, it is found more convenient to dissolve the sweetening agent in warm solutions of alcohol and water. Warm glycerine also dissolves it well, but the presence of glycerine would unfit the solution for domestic purposes.

Saccharine promises to have three great fields before it, if not more. Its culinary uses may not be very great-though opinions are divided on that pointexcept for the preparation of sweetmeats and confectionery; and as it has already been found possible to manufacture pure and wholesome sweets flavoured with it, and not containing cane sugar, it can hardly fail to give a decided impetus to the sweetmeat trade. Unfortunately it must not be forgotten that sugar is a valuable and cheap food, agreeing well enough with most people, and the substitution of minute quantities of saccharine for common sugar will diminish the nutritive properties of the foods to which it is added. Again, it can be used to cover the sickening taste of many strong drugs, at any rate, the medical papers promise, in their usual hopeful spirit, great things in that direction. Every practical physician soon learns, however, that tasteless and so-called palatable preparations of strong modern medicines are often, after two or three doses, most repulsive to the patient, and it may be found that after the first wonder is over, people will prefer the drug in its ordinary form to taking it mixed with saccharine. Time will show; and we .cordially wish the enterprising chemists who have taken up this part of the work all the success their good intentions merit.

Lastly, saccharine is not changed in its passage through the body, and does not ferment like canesagar. It is also said to have powerful antiseptic properties; in many cases, therefore, in which the aged sufferer craves for sweets, but cannot, without pain indulge in that, to him, dangerous luxury-canesugar-he will now, we must hope, be able to fall back upon saccharine, which, again, in many familiar, but not the less loathsome and destructive diseases, is found to be an invaluable help to the skilful physician.

We have, we think, said enough to show that, much though the world owes to chemistry and to coal-tar, it is not often that a discovery like that of saccharine gives promise of greater things to come in the days, not perhaps far distant, when the chemist will, in his laboratory, manufacture many of the -commoner and more useful foods.

Wimborne.

Fig. 21.-Mature female. (m) mouth; (ph) pharynx; (") position of nervous ganglion; (g) gizzard; () intestine; (7) lower portion of intestine; (a) rectum; () anus; (s) style.

one-tenth of an inch in length, the mature male, one-fifteenth. Both sexes seem to vary in size.

The body is long and filiform, of nearly uniform thickness, but tapering gently towards the head and less gradually towards the tail, which ends in a long, fine spine. The transparent body permits a close examination of the internal structure.