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opposed to any method that wets them, as it mats the pubescence and frequently prevents indentification.

For mounting, I recommend the long Carlsbad pins, of which Nos. 0 to 4 are the most useful; the very minute species being pinned with the "minutien Nadeln," German pins, which are then stuck at one end of a small oblong piece of white pith, a Carlsbad No. 4 pin being put through the other end, and the pith pushed half way up the long pin. (See diagrams.)

The larger specimens should be placed above the middle of the pin, which should pierce the centre of the thorax.

I adopt the long pins for the following reasons: 1. The specimens are exchangeable with conti

Fig. 13.-Methods of mounting Diptera.

nental correspondents, all of whom adopt this method of pinning.

2. They are easier to handle and therefore less liable to accident.

3. They allow a higher magnifying power to be brought to bear on them when in the cabinet by being nearer the glass.

A second important point to be observed in mounting is not to set the flies. They are as useful for scientific purposes unset as set, they are easier to handle, less liable to accidents, exchangeable abroad, and by not setting them a vast amount of time is saved.

I am aware that, on this point my opinion is directly opposite to that of our leading dipterologist, but still see no reason to change it, as it is only in exceptional instances that unset specimens cannot be identified, provided the directions given below are followed.

So long as the wings are extended vertically (and not allowed to cling together) and the legs kept from folding up close under the thorax, there is no difficulty in naming them, which is the chief objection raised by those who insist on the necessity of setting.

Their second plea-lack of uniformity in unset specimens appears unsupportable, as a collection of Diptera pinned in the continental style seems to me as uniform and elegant as one in which the legs and wings are extended after the fashion of setting Lepidoptera. Moreover much cabinet space is saved by not setting them.

Every specimen should be dated and localised with a ticket attached to the pin below the insect. Specimens may be relaxed by placing them in

laurel, and for preservation against mites when in the cabinet, naphthaline is most frequently used by continental authorities, it being almost unnecessary to add that the cabinet should be kept in a warm dry

room.

4. CLASSIFICATION.

Hardly any author's classification can be considered a standard one, the order having undergone such important revision during the last twenty years.

Several of the older authors, owing to their incomplete knowledge of the order, added altogether to our lists some hundreds of species that have no right to a place there.

Moses Harris was the first to write on the British diptera, and relied chiefly on the neuration as a basis of classification.

Curtis' work (1823-40) gives 112 really excellent coloured plates, and notices many species that he does not illustrate; his generic descriptions also being complete, and, in the main, trustworthy; but no attempt is made at analytical tables of genera or species, and many of the introduced species are now repudiated.

In Walker's work (1851-56), about 2000 species are described, though scores (I might almost say hundreds) of these descriptions are worthless. His work, however, is a most useful one to have, as a good general knowledge of the order can undoubtedly be obtained from it.

His analytical tables are not always good. He divides the order into three great groups, as follows:

Antennæ lying flat in cavities in the head: Suctoridea (Pulicida).

Antennæ seated on the front of the head.

Legs at juncture with thorax close together: Proboscidea.

Legs at juncture with thorax wide apart: Eproboscidea.

His table of families is unsatisfactory, inasmuch as two families (Empida and Muscida) are split up and fall in both his subdivisions of Brachycera.

He divides the Proboscidea as follows :

Antenna with distinct joints, at least six, usually more than 10: Nemocera.

Antennæ, three to ten jointed, after the third closely jointed.

Posterior veins branched or interlacing: Brachycera. Posterior veins simple, detached, faint: Hypocera (Phorida).

He gives nine families of Nemocera, seventeen of Brachycera, and two of Eproboscidea.

Books on this order are few and costly, the following being the principal ones relating to British Diptera :-Moses Harris, "Exposition of British Insects," 1776-1782. Curtis, "British Entomology," 1823-1840. F. Walker, "Insecta Britannica: Diptera," 1851-1856. Rev. F. O. Morris, "Catalogue of British Diptera," 1865. G. H. Verrall, "List of British Diptera," 1888.

No student should be without Mr. Verrall's list.

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Diagram showing classificatory structure of Wings of Diptera:-Fig. 14. Cecidomyia; Fig. 15, Hormomyia; Fig. 16, Sciaria; Fig. 17, Mycetophila; Fig. 18, Scatopse; Fig. 19, Bibio; Fig. 20, Diplosis; Fig. 21, Simulium; Fig. 22, Glaphyroptera; Fig. 23, Chinonomus; Fig. 24, Psychoda; Fig. 25, Pericoma; Fig. 26, Rhyphus. Note.-All these wings are, of course, magnified, as shown by comparative measurements thus.

Meade, "Ent. Month. Mag." 1881. "List of British Tipulida" (with tables and notes), Verrall, "Ent. Month Mag." 1886. "List of British

Stratiomyida" (with tables and notes), Brunetti, "Entomologist," 1889,

The best works on European Diptera are the

following:- Mergen's "Systematische Beschreibung," 5 vols. 1818-1838, Germany, Macquart, "Diptères,” 2 vols. 1834–1835, France. Zetterstedt, 'Diptera Scandinavia,” 14 vols. 1842-1860, Scandinavia. Rondani, "Diptera Italicæ," 7 vols. 18561871, Italy. Schiner, "Fauna Austriaca," 2 vols. 1862-1864, Austria. Desvoidy, "Diptères des Environs de Paris," 2 vols. 1863, France.

The only catalogue of European Diptera is that by Schiner, published in 1864, giving about 670 genera, and 8600 species as European.

Schiner and Loew are, perhaps, the best recent Continental writers, and as no linear arrangement of families (entirely consistent with the structural characteristics of the various families) is possible, I shall adopt the sequence of Mr. Verrall in his lately published list as being the best and most recent authority on British Diptera.

Schiner (1862) gave a large quantity of introductory matter relating to the structure of the Diptera, but in his table of Brachycera families he, as Walker did, makes some families (Empida, Dolichopida, and Conopida) fall in both his primary divisions-which appears to me very undesirable; though I must add that I cannot myself suggest any table of families which shall be flawless in this respect.

In 1864 Schiner proposed dividing the Diptera into two great divisions—Orthorhapha, in which the pupa is sometimes coarctate, but in all cases the larva skin is slit longitudinally in the dorsal portion, to give exit to the pupa or perfect insect; and Cyclorhapha, in which the pupa is always coarctate, the perfect insect escaping by throwing off a sort of lid at one end of the dried larva skin which forms the cocoon.

In the same year Lioy submitted another classifi cation.

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families of Brachycera and Nematocera, given in this paper).

2. Cyclorhapha.-Syrphida, Conopida, Platypezida, Pipunculida, Oestrida, Muscida (he raises all my six sub-families of Muscide, and all the groups of Acalypterata, to the rank of families), Phorida.

3. Pupipara.-Hippoboscida, Nycteribiida.

I have not adopted either Schiner's or Brauer's latest systems; as, in a paper intended specially for beginners (as this is), it appears to me the tables should be based on characters of the perfect insect, not on those of the larva or pupa, with which the student probably would not be familiar. At the same time, I fully recognise that the structure of the pupa case is of the highest importance in classifying the Diptera.

5. DESCRIPTIONS AND TABLES.

In the Diptera the mouth is suctorial, the proboscis usually being rather long; there are two maxillary palpi; the thorax is compact, the pro-thorax and meta-thorax being very short, and the meso-thorax

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Fig. 27-AA, costal vein. 1, first longitudinal vein (often double); 2, second ditto: 3, third ditto; 4, fourth ditto; 5, fifth ditto; 6, sixth ditto, or anal vein; 7, axillary vein; w, internal transverse vein; L, external ditto; aa, costal cells; b, marginal cell; c, submarginal cell; d, first posterior cell; e, second ditto; f, third ditto; g, discoidal cell; hhh, basal cells; x, costal spine (often absent).

much enlarged; forming the greater part of the thorax; the scutellum is rather large; the abdomen is usually formed of from five to seven segments; the wings are two in number, the posterior pair being replaced by alulæ, and a pair of filimentary appendages, clubbed at the tip, known as halteres; the legs vary greatly in size and length, the tarsi being pentamerous.

The Pulicida (fleas) do not appear to me to be true Diptera; so, although Mr. Verrall includes them in his list, I have eliminated them, as does Schiner in his "Fauna Austriaca." I may observe, however, that three genera and thirteen species are British.

The wing of one of the Anthomyida is given, with the terminology adopted by Dr. Meade and other British authorities (after Loew). It is exceedingly unfortunate that there exists such a diversity of opinion in the matter of terminology.

It is manifestly quite impossible, in the limited space at my disposal, to give more than a bare outline of the characteristics of each family, and a brief de

scription of a few of the commonest species. Analy. tical tables of all the genera are out of the question: but I shall insert as many as possible, and these, with the plates of wings, will be found quite sufficient to enable the student, after a little study, to recognise all the families, and the greater number of the principal genera. In the small crosses, representing the natural size of wings given' in the plates, allowance must be made for slight variation in the size in the different species.

The tables are intended to apply to the British genera only, and are compiled with a view to render the determination of sub-families and genera as easy as possible; and they may not always be the best from a strictly scientific point of view. The descriptions are purposely abbreviated as much as possible to save space.

(To be continued.)

DUCKING: A LINCOLNSHIRE SKETCH. By GREGORY O. BENONI. [Continued from p. 18.]

ΑΝ

N amusing sight it is to the naturalist to see the bright-eyed speckled breast at his work, his legs straddling wide apart with exertion, and his whole being bent on the business in hand. He runs his beak into the soft body of the snail, and begins to hammer, rap-a-tap-tap, till it escapes from his hold. Then he hops round a while in reflection, wags his tail, and takes his rest with his head cocked to one side, and his gaze fixed on the dainty morsel enclosed in the protecting shell. When he has quite recovered his breath be "goes for it " again, this time with his "nib" thrust through a crack in the shell, which soon flies to fragments under repeated blows, and discloses the coveted treasure.

But this is not ducking, though we are almost within sight of the decoy, and the master-ducker is hastening down the path to meet us, with a "God bless you, squire, I'm right glad to see you and your friends; 22 an assertion fully in harmony with the beaming expression of his weather-beaten countenance, and the eagerness of his movements. To our inquiries whether we might see the ducks taken, and what kind of day might be expected, he answered with a wink of extreme satisfaction, as he swung his left arm towards the pond; "First rate, squire, first rate ducking-day, five thousan' i' th' 'coy if there's a score, I'll awarṛan'."

After a few more words relative to the splendid weather we were having for what he maintained to be the finest of sports-certainly it does require great caution and intentness-our entertainer conducted us through a young plantation of birch and ash, bidding us speak in undertones lest the ducks should hear us, and finally commanded us to observe perfect silence. He then vanished into a shed, and returned with a basket of hemp-seed, and some

morsels of bread for the decoy-dog who now appeared following its master. It was a dog of the ordinary north of England shepherd type, half colley and half bob-tail, but worth a "fo'tin" to its owner notwithstanding its unassuming exterior.

66

Accompanied by this new addition to our party, we soon found ourselves close to the decoy, a circular sheet of water, four acres in extent, which had been made by deeping the natural hollow between two 'hoes" or sand-hills, heaping up the soil thus gained round the edge of the pool, and supplying it with water from a drain connected with the Trent. A pipe, or gradually narrowing canal a hundred yards long runs out from the pond towards each of the cardinal points, curving to the right as it recedes, so that the birds on the main-water, or at the entrance of the pipe itself, cannot see more than

Over the entire length

half-way along its channel. of each pipe is a semi-circular iron frame supporting a net with a mesh of two inches, high in proportion where the ditch is wide, and contracting by degrees till it ends in a tunnel-net kept open by iron rings, and removable at pleasure. On the left side of each pipe runs a high fence, formed of a series of reed screens, so placed that the head of one is somewhat behind the end of the next, and only connected with it by a low stile or dog-leap, over which the observer can look straight up the pipe.

Wild fowl are so continually on the alert, and have such exquisite senses of sight and smell, that they can only be approached under cover from the leeward; woe betide the sportsman in the open fens, who believes himself to be getting within range of his game after hours of wary stalking, if the wind veer but a few points and blow from him to his would-be quarry in the twinkling of an eye the birds take wing, and he is left to console himself with the thoughts of what might have been, if his fortune had proved equal to his endeavours.

The pipes of the decoymen, are purposely so arranged that two can always be used at a time when the wind will blow steadily from one quarter. But the breeze must be constantly watched for fear that a sudden change should inform the ducks of their danger, and cause a sudden "rising," when mallard, teal, shoveller and pintail will disappear, leaving the common enemy to duckless and luckless lamentation.

While we were still some two hundred yards away our ears had become aware of unusual sounds, but now we were within a few feet of the water, the cry, quack, whistle, and cough of strange and unknown birds became most exciting. Initiated by the sign language of the decoymen, we placed ourselves at squints, or peeping-holes, formed by thrusting short sticks through the reed fence, but not before our long-limbed cockney friend, whose curiosity got the better of his discretion necessary on such an occasion, made our worthy instructor forget himself and his betters, by an attempt to look over the screen into

the pond. When we were fairly settled in our places we beheld a sight never to be forgotten. There on the water close before us were thousands of lovely birds in their most perfect winter plumage, splashing, diving, musing, sleeping, or unconcernedly pruning their feathers, as if they were on some island of the Arctic Sea untrodden by the foot of man. Teal, pochard, widgeon, shoveller, gadwell, mallard, and I know not what-for time failed to observe the minute details of the wonderful scene-were sporting before us, the very embodiment of grace, or sunning themselves on the water's edge. One pair of mallards were performing the ingenious and pretty feat of swimming round one another, and making a circuit of the pond at the same time,—as astronomers tell us that some twin stars move through space. The air reverberated with constant cries, which apparently had their source in the jealousy of an unusual number of drakes; and the sound of many wings broke ceaselessly on the ear.

We had gazed for some time in wonder and admiration, when the old "ducker" joined us, delighted to observe what pleasure his unusual show was giving. For although we had often watched the fowl before, it had never been our lot to see such numbers of common wild-duck, or so many rare birds on the pool together.

"Now did ye ever see sich a sight o' ducks onywheare in your life? Why, I tell ye, ye wouldn't see it in England, nor in the world, I'm thinkin'," he whispered, as he mopped the perspiration from his forehead with heavy dabs from a heavy silk pockethandkerchief.

"Well, it is a splendid sight, and such a one as we have never seen before," we replied, in the same scarcely audible speech he himself used.

"A splendid sight," drawing back, and holding out his hand, as if our qualifying adjective had not been strong enough; then, nearing again, so as to allow his ghost-like voice to reach us, "I've had gentlemen in days gone by who would have come three hunded miles to see such a vast o' em in at once. My governor "-his old employer-" would ha' had all his fine friends here, if he'd been alive, he would." The work of capture now began. The boy donned a bright red flannel vest, and stationed himself behind the first "shooting or screen, lying flat on the ground, and hidden from any ducks which might enter the pipe by the low connecting stile. His grandfather then threw a piece of bread over it on to the strip of land between the "shooting" and the water's edge, and the dog immediately bounded after it and returned by the second stile, though not before the ever-observant ducks, on the near side of the pond, had noticed his presence.

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The whole decoy was on the alert for danger at once. The birds on the shore took refuge in the water, those which were swimming stopped for a time, and all eyes watched for the unknown apparition

to present itself again. The dog leaped several times over the first stile, returning by the second, then over the second and back by the third, and so on, retreating gradually, every fowl regarding the performance with fear, wonder, and curiosity combined. Yet as he made no attempt to injure them, but moved slowly away up the pipe, they presently fell back on their ordinary sense of security, and began to sleep, dive, and coquet again. The fatal desire to increase their stock of available knowledge-the bane of other than feathered victims-evidently over-mastered the prudence of a score or two of birds. They began to follow the mysterious object in its retreat, hesitating some time at the mouth of the pipe, swimming this way and that, straining their necks, and turning their bright eyes hither and thither, in a vain effort to learn the meaning of the overhanging net, or to watch the dog passing out of view round the bend in the pipe. The bolder ones entered when the dog disappeared, followed by their more cautious companions, though some few retired discreetly at the last moment. Under the net they sailed, unconscious of the meaning of the treacherous meshes above them, till, at a given signal from the decoy-man, the redvested lad leapt to his feet and showed himself over the stile in their rear.

The effect was magical. The shy explorers took wing together without a cry or warning to those left behind, and not daring to face the foe, fly forwards, catching sight of each of us in turn as they pass the stile of the screen through which we are watching. Dashing through the water in mad fear, or beating their wings against the imprisoning net, only to be thrown back to their native element again, they reached the end of the pipe and entered the circular net prepared for them, which the decoy-man removed as soon as the last of the "take" had passed into its jaws.

Now came the poor sport of the show-the killing. This was performed by the expert placing his fingers over the beak, the thumb over the first joint of the neck, and then giving the head a backward jerk to the right side of the neck, which caused the immediate dislocation. Painless enough as deaths go, but an inglorious ending for the freedom-loving mallard and teal.

The whole affair was a dumb-show of a few minutes' duration. Not a single word was uttered aloud till the decoy-man had killed and counted twenty-eight birds. Then, wiping his brow with the sleeve of his coat, he said, with a grin of satisfaction, "Fust-rate sport, Squire; your friends never saw owt like this before, nor never will again."

This mode of taking wild-fowl is called "working them" by professional duckers; but it is more commonly known on paper as the "dog-decoy." It is often productive of a fair take, especially of birds fresh from the north, but it is far surpassed by the "duck-decoy " now to be described.

(To be continued.)

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