Piophila casei, L., is the common "cheesehopper," living in old cheese. The imago is shining black, with the lower part of the face yellow; clear wings; hyaline black legs with the base of the femora and tarsi yellowish; long 3-3 mm.

The other British species, P. luteata, Hal., is closely allied, the larvæ living in old bacon. Kirby and Spence have described its life history.

The Ephydrina are a group of closely-allied,

sombre-coloured small flies, of which the British species have been worked out by Haliday. They are tolerably abundant in Ireland, but also occur all over England in grass, fungi, and ditches; some on aquatic plants, and a fen on the sea coast, and in salt-marshes.

Hydrellia griseola, Fln., probably the commonest species, is blackish grey, with clear wings, reddish eyes and black face, which, when seen from below, shows a wide whitish stripe in the centre; long 3 mm.

Drosophila, Fln., is found on Crucifera, the larvæ feeding an oak-apples. Their movements are slow; at least one species (D. funebris, F.) occurs in houses, collecting round beer and wine casks. Reaumur described the larva of one species.

Meromyza, Mg., is a genus of limited extent, of small black and yellow flies, inhabiting herbage. Two species are common; the peculiar venation affords an easy means of recognition.

Chlorops, Mg., is an extensive genus, of which Verrall gives eight species as indigenous, though probably several more will be found in Britain, most of them common, living in the larval state on wheat and barley, one species thus destroying the sexual organs of the barley.

Sometimes they occur in swarms. The species are closely allied; generally yellow in colour, marked with black; but some of them are tolerably easy to recognise. They inhabit sunny fields and banks, chiefly occurring during July and August.

Oseinis, Latr., infests wheat, their habits being similar to those of Chlorops.

Agromyza, Fln., supplies us with eleven species, found in fields and woods; small darkly-coloured flies; closely allied.

Phytomyza, Fln., has a venation of its own, and is allied to Agromyza. The European species of this genus, as in Agromyza, are very numerous. They occur on plants from April till the end of summer. Walker speaks of a species infesting the cornfeverfew.

Borborus, Mg., is a genus of well-built, sombrecoloured flies, several species being common, especially B. equinus, Fln., which is a small brown fly, the abdominal segments being sharply marked off; the face yellowish; the legs brown, with lighter tibiæ; the wings nearly clear; very variable, especially in colouration of legs; long 3-4 mm. Haliday has monographed the British species of

Borborus. The larvæ live in decaying animal and vegetable matter.

In Limosina, Mcq., the venation is again peculiar to itself, about twenty species being British. Haliday has monographed them.

xiii. 2.

Orygma Dryomyza

Asteia, Mg., is found on haystacks. Cordylura pubera, L., Wlk. ii. Pl. Scatophaga scybalaria, L., Curt. 405. luctuosum, Mg., Wlk. ii. Pl. xiii. 5. flaveola, F., Wlk. ii. Pl. xiv. 1. Sciomyza albocostata, Fln., Wlk. ii. Pl. xiii 7. Tetanocera ferruginea, Fln., Wlk. ii., Pl. xiv. 2. Psila fimetaria, L., Pauz. XX. 22. Ortalis guttata, Mg. Curt. 649. Ulidia demandata, F. Wlk. ii. Pl. xv. 4. Tephritis corniculata, Wlk. ii. Pl. xv. 6. Sepsis annulipes, Mg. Curt. 245. Chlorops taniopus, Mg., Curt. Farm. Ins. Pl. H. Fig. 2. Agromyza denticornis, Pauz., Wlk. ii. Pl. xviii. 3. Limosina sylvatica, Mg. Wlk. ii. Pl. xiv. 9.

30. Phorida.

Over twenty species of this family are British, the larvæ feeding on animal and vegetable substances. Bouche thinks some species are parasitic on larvæ.

Phora rufipes, Mg., lives on nearly everything, a correspondent of mine once bred it from a beetle (Rhizostrogus solstitialis, Latr.), one of the scarabaeida. It is a blackish-brown fly, with pale yellowishbrown legs and clear wings; long 2 mm.

The venation of this family is easily recognised, being unlike that of any other group.

Phora rufipes, Mg., Wlk. ii. Pl. xix. 6. abdominalis, Curt. 437.

III. EPROBOSCIdea.

P.

In this group the larvæ and pupæ are developed in the abdomen of the female. In the imago the head is retracted, and the antennæ placed in a cavity in the head. Wings rudimentary or abnormal; parasitic.

31. Hippoboscida.

All the species of this family are more or less uncommon; the antennæ are stylate, the prothorax distinct.

Hippobosca equina, L., known as the forest-fly, is parasitic on horses and cattle, and occurs in the New Forest and other parts of Britain. It is brown, the dorsum of thorax darker, with a pale yellow triangular spot in the centre; scutellum yellow; wings, abdomen, and legs pale brown; long 7 mm.

Melophagus ovinus, L., is the sheep-tick. The head is distinct from the thorax, the antennæ are in the form of tubercles; no ocelli.

Stenopteryx hirundinis, L., lives on the swallow, and is not unfrequently found in their nests; head placed in a cavity of the thorax ; antennæ ciliated; ocelli present.

Ornithomya avicularia is parasitic on birds, usually the plover, partridge, and lark.

Curtis gives good plates of three species:H. equina, L., Curt. 421. S. hirundinis, L., Cuit. 122. M. ovinus, L., Curt. 142.

32. Braulida.

The one British species of this family, Braula caca, Nitzsch, is a small, horny, shining red-brown apterous fly with black spines and hair; proboscis prominent, horny, yellow; antennæ three-jointed; scutellum and hæteres absent; legs short, all of equal length; tarsi five-jointed; last joint with large broad claws. Parasitic on bees; very rare.

33. Nycteribida.

In this family the body is crustaceous, the head small, the legs thick, long and bristly, the abdomen being composed of five or six segments in the d, and only two in the 9. The coxæ are remarkably large.

Two species of Nycteribia are British, N. Hermanni, Leach, and N. Latreillii, Leach, the latter being rather smaller than the former; both species are rare, and infest the common bat.

Nycteribia Latreillii, Curt. 277.

In conclusion I should like to reiterate that this paper is only intended as a groundwork on which beginners can build up a more extensive knowledge of this order, and is written more for the purpose of gaining this neglected group additional students than to represent even an approach to a handbook of British Diptera.

The descriptions, though short, are, I trust, concise, and may enable beginners to obtain a fair acquaintance with the general appearance and structural characteristics of the majority of families and sub-families; and I am in hopes that the diagrams of wings, though only roughly delineated, may supply the student with the means of identifying many a genus.

I may add that, whenever my limited hours of leisure permit, it always affords me the greatest pleasure to render any assistance I can-in the way either of naming specimens or supplying further information on any particular group.

E. BRUNETTI. 129, Grosvenor Park, Camberwell, S.E.

popular theology. The greatest populariser of the latter was Christ himself. Knowledge, to be useful, must be democratic. Hence we have no sympathy with the few prigs who would keep what little they know to their own select circle; and, whenever they have anything to say, say it in the least understandable and most technical phraseology their limited knowledge of language permits. All knowledge belongs to humanity, and the man who undertakes the responsible position of interpreter of science to the people, occupies a most important place. It is given to but few men to be real teachers and genuine popular writers. There have been thousands of schoolmasters, but only one Dr. Arnold; hosts of naturalists, but only one Gilbert White and one Richard Jeffreys. The genuine populariser of science possesses a distinct and rare gift. You can train thousands of specialists to any department of work, if they only possess industry enough; but all the training in the world would not make popular instructors of them, like Charles Kingsley, Richard Proctor, and Andrew Wilson. Therefore we welcome this charmingly got-up book, with whose contents many of our readers have doubtless already made themselves partly acquainted in the pages of the "Illustrated London News," where there may have been suggested to them the desire to see these clever papers collected in an available and consultable form. The numerous illustrations, which accompany the text now for the first time, render the descriptions all the more intelligible.

Our Country's Flowers, by W. J. Gordon (London: Day & Son). A beginner in English botany could not do better than procure this book. It is illustrated by upwards of 500 chromo-lithographs, which, if a trifle over-coloured, can easily be allowed for, and will doubtless tone down. Besides these, the chapter headed "Index to the Genera" has a clear and easily understood woodcut of the generic characters of each kind. The chapter "Index to Species" gives a clear account of each species of wild-flower. There are also chapters on "Local Names," "Classification," "Tabular Scheme," "Natural Orders,' 'Examples of Identification" (a very useful chapter to a beginner), "Derivation of Generic Names," &c., as well as a copious glossary. As it is bound in limp cloth, it can easily be carried in the pocket. For the purpose of merely identifying common British plants, it is one of the best and cheapest works we have.

Handbook of the London Geological Field Class (London: George Philip & Son). A neat, handy, and much required manual for the happily increasing tribe of amateur London geologists. Five years ago Professor Seeley, F.R.S., started a London field class for geology, and took the members to all the best sections and fossil collecting-grounds round the metropolis. Professor Seeley is a born teacher, and delights in his work. You have only to interrogate

any of the students of his field-class to find with what affectionate enthusiasm they regard him. The present volume is in reality the notes made by the students themselves, and is a sample of their notebooks and records of observations. It is a capital digest of Professor Seeley's lectures on these occasions. The book is illustrated by capital sections drawn by Mr. Nicol Brown. It is a record of honest work earnestly done, and is therefore both a vade-mecum and a stimulant to all those who desire to explore the interesting geology of the London district for themselves.

Outlines of Field Geology, by Professor A. Geikie (London: Macmillan). This is the fourth edition of Professor (now Sir Alexander) Geikie's wellknown and popular little book. We have no hesitation in saying it is the best of its kind ever issued. No other authority is so capable of teaching field-work, considering his position as the Chief of the Geological Survey, and none other is more ready to teach. The present fourth edition has been thoroughly revised and considerably enlarged, and there is much in it which is new, especially that part giving an account of the schistose rocks. New illustrations have also been added where necessary.

Among the Butterflies, by B. G. Johns (London: Isbister & Co.). We are pleased to see Mr. Johns so capably following his father's footsteps as a good naturalist. The present little volume is handsomely got up, and the twelve plates, which contain sixtyseven figures of our English butterflies, are excellent specimens of natural history wood-cutting. Mr. Johns is possessed of much literary ability, and tells his story pleasantly and gracefully. This ought to be a very popular little book.

The Human Epic. Cantos I.-V., by J. F. Rowbotham (London: Kegan Paul & Co.). The author of this suggestive poem is an old contributor to SCIENCE-GOSSIP. He has already won his spurs as an acknowledged poet; and this, his latest book, affords fresh evidence of the natural insight which all genuine poetry possesses. Tyndall somewhere says that the rhythmical movements of the molecules of a drop of water, and their relations to the mysterious and unknown forces governing them, if even baldly told, transcend in dramatic interest a book in "Paradise Lost." Mr. Rowbotham is one of the first of the younger school of poets to see the vast advantages which science holds out of subjects for poetic treatment. Tennyson made the discovery half a century ago. Mr. Rowbotham heads the five cantos of his "Human Epic" as follows: "The Earth's Beginning," ," "The Origin of Life," "The Silurian Sea," "The Old Red Sandstone," "The Age of Trees." Geology is full of natural poetry, and the author is a good geologist, as well as "Scholar of Balliol College, Oxford." We cordially commend Mr. Rowbotham's charming cantos to all nature-lovers.

THE

ROSSENDALE RHIZOPODS.

No. 4.

HE genus Centropyxis is also a very common form here, and from the writings of others, appears to be widely distributed. I find it in almost all my collecting-places, the various wells, ponds, and ditches furnishing well-marked varieties. It is closely related to Difflugia; and indeed it is frequently impossible to determine to which of the two a particular specimen may belong. The shell is of various shades of brown, and is composed of chitinoid membrane, incorporated or covered with a variable proportion of quartz-sand or diatoms; the latter, however, I do not find so frequent a constituent of these shells as in the genus Difflugia. The greater number of those having a diatomaceous covering, I procure from several shaded wells where those algæ are plentiful. From Sphagnum, most of the forms of this genus have had the chitinoid membrane, either straw-coloured or a pale, smoky brown, sometimes with a few scattered sand-grains, more frequently entirely without. In my experience the shells of this variety are very shallow. The brown membranous base connects this genus with Arcilla. In the ordinary form, the test appears on the dorsal, on ventral aspects, sub-circular or ovoid; but on a side view, which is not quite so frequently presented, it will be seen to be deepest behind the mouth; in other words, the mouth and top of the shell are eccentric in opposite directions. In this particular it resembles Difflugia constructa, so much so indeed, as to be with difficulty distinguished from it. The chief points of differences between the two are that Centropyxis is more decidedly brown, is not so high from the mouth to the fundus, and the margin of the inverted mouth is prolonged into two or more appendages. The drawings will help to make clear the form and general appearance. It will be seen that on a side aspect it is somewhat cap-shaped, being highest behind the oval opening. The most common form has a variable number of spines, more or less divergent, from two to nine, placed laterally and dorsally. These are of the brown basal membrane only. The mouth is large, sub-circular, deeply inverted, and according to Professor Leidy, the margin is produced in one or more appendages. This is generally, from the opaqueness of the shell, impossible to make out, and I have myself never been able to demonstrate the peculiarity, though I have had hundreds under observation at various times. In no case can it be seen, except in the lateral aspect of the shell, and only then in specimens of clear chitine, free from sand-grain. Size from You too of an inch.

Fig. 152. A very common form here, of linear and navicular diatoms; with spines.

Fig. 153. Side view of large specimen, whose test is composed of large and small sand-grains.

Fig. 154. Same test, ventral aspect.

Figs. 155 and 156. Front and side aspects of a dark brown variety, test, sand and dirt.

Fig. 157. Test of smoky yellow chitine, incrusted, posteriorly with flocculent dirt, but no sand-grains or diatoms. From Sphagnum.

The genus Arcella disputes with the previous form the honour of being the commonest of the testaceous Rhizopods. They are generally found in association, and there are few microscopists who are not familiar

colour, though occasionally I have found colourless specimens. This membranous test has a minutely hexagonal, cancellated structure, something like the marine diatom Coccinodiscus, though this is not always demonstrable. Many of the varieties have really elegant shells, the dome of some having angular facets, or pits, which being thinner and lighter in colour than the connecting parts, have a charming effect. In A. dentata there are a variable number of recurved spines, arranged round the circumference of the shell, and I figure a form in the ventral aspect, somewhat approaching this, though not sufficiently so to justify its being placed in that species.

In A. vulgaris or communis, as it is indiscrimately

Fig. 155.-Centropyxis aculeata.

Fig. 156.-Centropyxis aculeata.

with their brown tests. Arcella is sometimes very numerous, not only in the light sediments of our ponds, but also among the Algae clothing the sides. It was discovered by the illustrious Danish naturalist Ehrenberg about sixty years ago. There are many varieties, some very striking ones, but the forms gradually merge into each other, so that many authorities consider them as one species. Leidy gives five specific names to the more widely separated forms, two of which, A. communis and A. discoides, are found in all the waters of this district. The shell is composed of chitine, light or dark brown in

Fig. 157.-From Sphagnum, above Balladen. Test of smoky yellow Chitine incrusted with dirt, but no sand-grains or diatoms.

called, the test as generally seen is a brown circular disc, with a central round opening for the emission of the pseudopods. On a side view, the outline is a low campanulate, with the basal border rounded, and the mouth inverted. The height is about half the breadth.

The sarcode is colourless and the mass rests on the base and around the inverted funnel of the mouth, and is connected with the fundus, or top of the shell, by threads of the ectosarc. There are two nuclei, one on each side, and several cont. vesicles. These details can only be made out in transparent speci

A DAY AMONG THE WILDFOWL.

WE started early this morning from the old and

well-known village of Bosham on our weekly outing among the birds, and anticipation ran high, for our two old boatmen, Kit and Bill, told us that never since the "Rooshen War" had so many wildfowl been seen inside and out the harbour. A fresh wind blows from the north-west, and as the tide is just at low ebb, we can scud down the channel between the mudlands, and so in a great measure escape the ice, which is now here in all but Icelandic severity. A hasty look round to see if all is ready for action and nothing forgotten, and then up sail and off. Day has just commenced, and the birds are astir and by this time fully aware that all men here have guns, and all boats under weigh have men. Close to hand sits solemn and still the heron, apparently fast asleep; for once he is allowed to stay, but had he been old, and in good plumage, his time would have been short. As the light varies other forms come into view. Carrion crows, gulls of all kinds and sizes, and all eager for the smallest of things in the way of an early breakfast. Curlews by dozens, starting up with their weird whistling; whaups, or trants, as they are called, very like the curlew, only smaller; turnstones, dotterel, dunlin, in thousands-so many in fact that one gunner shot twenty-seven dozen and five at one shot-and last, but not least, the homely ever-present rook, driven from the fields and pastures to the muds and flats to pick up a strange living by the tide. On scuds the boat, her crew all alert for sport, and as strange birds do not visit here every winter, each is anxious to find at least one prize as a memento of this severe time. "Burds ahead," quickly says Kit, and with that from the bows he produces a long and well-worn old fowling-piece, which he said had done great work in his father's time. Not a movement on board, and as the boat comes up to them away they go, all over the place, giving us just the slightest chance to score, and out falls a mallard with a dull thud-dead. This is the commencement of a glorious day, and now that the guns have started the game, strings of birds are seen passing right and left, some going up and

some down, all in a hurry, and all out of shot. Our mallard retrieved, on we go, for our destination is some five miles lower down, to the mouth of Chichester Harbour, and as long before daylight we have heard guns there, we know good sport is going on, and want to be in the thick of it. Not very far down we fall in with three divers, which prove to be golden-eye ducks, and as we run down on them they rise against the wind all together, and the long gun brings them down in a pretty little heap, fortunately too lifeless to try to get away. Still on we go, and the farther we go the more the excitement grows, for there are birds everywhere in sight, and if this is so inside the harbour, what must it be outside? Soon we get near the old coastguard ship, and a short council of war is held to decide where to go. First we all land, and cross the shingle bank that divides the harbour waters from the outside sea, and what a sight meets our view! As far as the eye can reach are wildfowl, large and small, on the water; surely the whole Arctic supply is before us, so vast is the number. There are acres of brent geese-thousands and thousands of them. Here and there grey-hags, bean and white-fronted geese show up, and amongst them two fine specimens of the snow-goose. Ducks and widgeons in hundreds, a few teal, scamp and pochard, tufted duck, here and there a Black Sea duck (Scoter). Diving birds there are of many kinds popping up here and there, grebes of one or two sorts in sight at once, with razor-bills and guillemots, and coming along from Selsey Bill is a long string of wild swans. We wait to see no more, but rush to the boat and quickly get one gun on Hayling Beach, another on the Point of Wittering Beach, and the boat itself right in the fairway of the harbour's mouth, to intercept this party, should they come inside. But 'tis no good, they just sail majestically along over Hayling Island, then turn up the left wing, and round into the Emsworth Channel, and are safe for a time. Our time is fully occupied in shooting with more or less success at the different parties coming or going, and fine sport it proves. Now a duck, now a widgeon, and now a goose comes tumbling down, first from one gun and then another, and still the hungry ones come on, for the food in the harbour flats. While we have been at our sport, other people have been busy, at one time no less than thirteen punt-gunners are in sight at once, and every now and again the roar of a great gun adds to the general commotion.

The day now wears on apace, and as the shooting is for a time slack a stroll round to see what the other gunners have got is the order of the day. From one we get a pair of shieldrakes, another has some broad-billed scaup-ducks, another a red-breasted merganser, another a splendid goosander, a fine old male bird, and can tell of a puntsman who has shot the hen, which we were afterwards fortunate enough to procure, together with a very beautiful male