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Abdomen quite bare.

Abdomen five or six-segmented, flat, wings broad and

large-triangular; Phasine. Abdomen four-segmented, globular, wings of normal shape,

rather small: Gymnosomina. Abdomen pubescent, large spines nearly always present. Abdomen five-segmented, long-genitalia very prominent.

Fourth longitudinal vein meeting third some distance

from edge of wing, fifth meeting fourth much beyond

middle of first post. cell: Ocypterina. Fourth longitudinal vein meeting third nearly at edge

of wing, fifth meeting fourth before centre of first

post. cell: Phanina. Abdomen four-segmented, conical,: genitalia not pro

minent: Tachininæ.

Exorista vulgaris, Fin., is a tessellated black and grey fly, subject to much variation ; wings clear ; face silvery-grey, with a central broad brown band; antennæ large, long, black ; legs black; alulae large, white; long 7-8 mm. Most of the genera are represented by two or three species only.

Nemoræa occurs chiefly in woods.

Gymnosoma, Mg., and Clytia, Desv., frequent the carrot plant.

In Myobia, Desv., and Metopia, Mg., the lays her eggs on the dead insects brought into Hymenopterous nests as food,

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The principal genera are Echinomyia, Dumer, Nemorea, Desv., Exorista, Mg., Tachina, Mg., and

Fig. 135.-Syrphus, F.

Fig. 139.- Xylota, Mg.

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Phorocera, Desv., but the state of our knowledge of the group is at present highly unsatisfactory.

Echinomyia grossa, L., is one of the largest British flies, and is a large black bee-like ily covered with soft black hair ; face, front and back of the head yellow, with short bright golden pubescence ; antenna tawny, tips black; legs black; wings pale grey, tawny at base and on the fore-border ; long 12-15 mm.

Olivieria lateralis, F., abdomen tawny, with a central dorsal black stripe enlarged towards the tip, and covering the whole of the last segment; thorax black with indistinct grey stripes ; face and front silvery grey; antenna and legs black; wings pale grey, brownish on fore-border ; long 7-8. Common in long grass.

Tachina, Nasicera, Exorista, Nemoræa, Echinomyia, and others are known to be parasitic on Lepidoptera, Serville thinking that Nemorea is also parasitic on Lepidopterous pupæ.

Gonia, Mg., is represented by five species, none common; the face is very broad.

Trixa, Mg., somewhat resembles Sarcophaga ; three species, larva unknown.

Alophora hemiptera, F. Pauz. lxxiv. Echinomyia ferox, Pz., Pauz. civ. Trira variegata, Mg., Wlk. ii. Pl. xii. 3. Gymnosoma rotundatum, L., Wlk. ii. Pl. xi. 6. Ocyptera brassicaria, F., Curt. 629.

(2.) Dexina. This small group is closely allied to the Tachinina, and calls for no special mention ; about twenty

Species non-metallic.
Middle ribia spined along its length: Calliphora,

Des.

Middle tibia spined only at tip: Musca, L. Species metallic green : Lucilia, Des.

species are British, nearly all representing a different genus each ; of Dexia we have five species. The larva of the Dexina are chiefly parasitic on Lepido. ptera ; the flies frequent flowers and dry, warm spots, and are often found in woods.

In Desvoidy's splendid work on the “Myodaires," he gives a lengthy list of the species of Tachinina and Dexina that are known to be parasitic, with the species of insect infested.

As a rule the abdomen is longer and more pointed in this group than in the Tachinina, and as in that group the legs are brittle and easily become detached from the body.

Prosena siberita, F., Curt. 665. Thelaira leucozona, Pz., Pauz. civ.

66

(3.) Sarcophagina. Dr. Meade, a few years ago monographed the British species of this group, which number about twenty, all (with one or two exceptions) being closely allied and exceedingly difficult to identify.

They breed in decaying animal matter, occasionally in dung. The imagos usually have tesselated black and grey abdomens—with strong spines towards the tip. The thorax is usually longer than it is broad.

Cynomyia mortuorum, L., is a large, bright blue fly which breeds in the putrid corpses of animals, generally dogs ; appearing in April and May. The face is bright golden yellow; the legs black; wings nearly clear. It is not common here, but is frequently met with on the Continent ; long 8-12 mm.

Sarcophaga, Mg., is a genus of Aies, in which the thorax and abdomen are divided into tessellated squares, the wings are pale grey, the legs black ;

and the thorax, abdomen, and legs covered more or less with spines, the number, length and position of these spines being important specific characteristics.

S. carnaria, L., the commonest species, is known as the “flesh-fly.”

In some species the extreme tip of the abdomen is bright red. The in this genus is viviparous, 20,000 larvæ having been found in a single specimen.

Lucilia, Desv., is a genus of bright metallic green flies, the face being usually black or green, the wings nearly clear.

At least six species are British, all more or less pubescent, and all very closely allied ; long 5-10 mm.

L. Cæsar, L., and L. cornicina, F., are the two most common species, appearing everywhere; the latter being easily known by its bright green face. These flies are sometimes known as

“green-bottles.” Calliphora erythrocephala, Mg., is the common meat-fly or “ blue-bottle ; a closely allied species, C. vomitoria, L., has a red beard. The progeny of this fly is said to amount to 500,000,000 in twelve months; and Mr. B. Lowne, who has made this species a study for many years, asserts that in the imago not one structure exists as it exists in the maggot.”

Musca domestica, L., is the common house-fly. Black and grey, with rather tawny sides to the abdomen; antennæ, legs, and eyes black; wings clear; thorax black, with grey stripes ; face silvery ; long 5-7 mm.

Mesembrina meridiana, L., is a rather large black hairy fly, with black snout and golden yellow cheeks; black mouth and eyes, black legs, grey wings, tawny at the base and along the fore-border; not uncommon; local ; long 10-11 mm.

Stomoxys calcitrans, L., is easily recognised by its strong, prominent proboscis. About the size of M. domestica, the abdomen being greyish with black markings ; usually found on sunny days on leaves and wooden posts ; it follows horses in numbers, and causes much irritation by its bite; long 6 mm.

Cyrtoneura stabulans, Fin., greyish, with pale brown reflections, larger tham M. domestica, common everywhere, especially in houses.

It has been bred from shallot, but the species in all probability breeds in a variety of substances.

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The flies of this group are the greatest scavengers of the order, the larvæ living in decomposing animal matter and devouring nearly all the fleshy part of the carcase. Sometimes they breed in dung.

About thirty species are British, many very

common.

The principal genera may be separated thus :

Of this extensive group of closely allied species, we have over 200 species. In many species it is impossible to identify the q, the specific characters being confined to the .

The larvæ of many species are leaf-miners, others live in the stalks of plants, in fungi, decomposing vegetable matter, &c., and damage the crops to no inconsiderable extent.

Dr. Meade published in the “ Ent. Month. Mag.," vol. xviii. (1881), a series of articles on this group, and in the number for Oct. 1883, gives an analytical table of the higher genera of Anthomyina.

This group is eminently a very difficult one to classify

Proboscis horny, projecting horizontally, prominent: Stomoxys,

Geoff.
Proboscis soft, vertical, not pro

nent.
Fourth longitudinal vein at its bend upwards not forming
a sharp angle.
Middle tibia spined along its length : Mesembrina,

Mg.

Middle tibia spined only at tip: Cyrtoneura, Mcg. Fourth longitudinal vein at its bend upwards forming a

sharp angle.

One or

12.

satisfactorily as many of the generic characteristics Homalomyia canicularis, L., is very common in are sexual, and such weak characters as the colour of houses ; ó blackish-grey ; abdomen tawny, divided the legs has been fallen back upon as distinguishing by a dorsal and two transverse lines into six squares, points.

tip blackish ; face silvery white, with a central black two well-marked groups may be dis- stripe ; wings pale grey; legs blackish ; variable ; tinguished, (as Hydrotæa, Homalomyia, &c.,) and long 4-5 mm. The males of this genus hover the principal genera may be recognised as follows :- together in the air in a group, sometimes for hours

together, and are often seen in rooms in early morning Alulæ of moderate size, scales of unequal size. Front femora in o too:hed, third and fourth longitudinal

hovering below the centre of the ceiling or near the veins convergent: Hydrotæa, Des.

windows. Front femora normal, third and fourth longitudinal veins parallel or diverging.

This species and another of this genus have been
Eyes pubescent: Hyetodesia, Rond.

bred from the human body.
Eyes bare.
Abdomen spotted.

Hylemyia coarctata, Fin., in the larval state does
Arista feathered : Spilogaster, Mcq.
Arista pubescent or bare: Limnophora, Des.

considerable damage to the wheat crop.
Abdomen unspotted.
Anal vein nearly reaching border of wing.

The larva of Cænosia, Mg. (allied to Caricea),
Arista teathered : Hydrophoria, Des. lives in cow-dung.
Arista pubescent or bare: Anthomgia,
Mg.

Over a dozen genera are represented by only one
Anal vein very short, curved towards the

or two species each. In several of the less developed axillary vein: Homalomyia, Bouché. Aluiæ small; scales of equal size.

genera the eyes are widely separated in both sexes, Arista feathered : Hylemyia, Des. Arista pubescent or bare: Chortophila, Mcq.

thus approaching the acalypterate Muscida, from

which they are scarcely structurally distinct. Limnophora, Des., comes chiefly from Scotland. Plates are not of much value in this group, except Hydrotæa dentipes, F., is a dark grey fly, with

to illustrate genera or very characteristic species. greyish reflections ; pale brown wings; black legs Hydrotæa ciliata, F., Curt. 768. Lispe tentaculata, and silvery cheeks, and is common in most parts; Deg., Walk. ii. Pl. xii. I. Anthomyia pluvialis, L., variable ; long 9 mm.

Walk. ii. Pl. xii. 2. Polietes lardaria, F., Walk. ii. Drymeia hamata, Fall., may be easily recognised Pl. xii. 9. Drymeia hamata, Fln., Walk. ii. Pl. xii. by its strong hooked proboscis. Hylemyia strigosa, F., is a bristly grey fly, the

(To be continued.) dorsum of the thorax being pale brown, distinctly marked off from the lower part of the thorax ; abdomen grey, with a dorsal and three transverse

A NEW SPECIES OF DASYDYTES-ORDER black stripes ; face silvery seen from above, black

GASTROTRICHA. viewed from below ; mouth and antennæ black; eyes reddish brown ; wings pale grey ; legs blackish, "HIS Order of the mighty worm-alliance seems tibiæ more or less dark tawny; common, especially

to have attracted very little, if any, careful in woods; variable ; long 6 mm. One species (H.

observation in this country of late years, although coarctata, Fall.) damages the wheat crop whilst in

both on the Continent and in the United States a the larval state, attacking the stalk.

great amount of attention has been devoted thereto. Anthomyia radicum, L., /, is a small black fly, Quite recently, in 1887-8, Mr. A. C. Stokes added breeding in cabbage and other like plants; abdomen greatly to our knowledge of the American forms, dark grey, with a dorsal and four transverse black describing in his papers in the “Journal de Microstripes; face and legs black; wings pale grey ; eyes

graphie,” numerous new species of Chætonotus and often with a silvery border ; very common on low other genera; while in 1889, Dr. Carl Zelinka pub. herbage and in London gardens ; long 4 mm.

lished an exhaustive monograph of the group (“Die A. sulciventris, Zett., is also common everywhere, Gastrotrichen,” in “ Zeitschr. f. wiss. Zool.,” xlix., the o is a nearly black fly, with unmarked abdomen. Part 2), in which all Stokes' recent species are The is greyish-black, with unmarked abdomen. included, and to which admirable work I can con

Caricea tigrina, F., common in long grass; bristly, fidently refer British microscopists desirous of exgrey with rows of black spots on the thorax, each tending their acquaintance with these creatures. giving forth a bristle, and with four brown spots on In our own country, Mr. T. Spencer described, in the abdomen ; legs black with tawny tibiæ ; face "Journ. Quekett Micro. Club,” January 1890, under grey with a broad central stripe ; eyes and antenna the name of Polyarthra fusiformis, an animal black; wings pale grey ; variable ; long 5-6 mm, which, however, is not a rotiferon, but (as pointed

Chortophila, Mcq., an extensive genus of small out by me in the same Journal, January 1891) clearly Alies allied to Anthomyia, many being tolerably referable to the genus Dasydytes of the Gastrotricha. common ; some of the species being parasitic on This must evidently be known in future as Dasydytes wild bees, Dr. Meade having taken them in the nests fusiformis, Spencer ; it is a pretty and curious little of the latter.

creature, very distinct from any previously described.

THI

In all probability, many or most of the species the skin are more or less visible, crossing the neck. recorded from the above countries, are also common The head is large and wide, three-lobed in dorsal to Britain, if observers would but search systemati- aspect, the lateral lobes prominent like puffed cheeks ; cally for them, and place on record such forms as the width of the head is nearly twice that of the neck, they may chance to meet with. It is for this purpose and about three-fourths that of the body at its widest of awakening interest, and so helping to increase our part. Both head and neck are usually considerably knowledge of our indigenous Gastrotricha, that this flattened, excepting the lateral head-lobes, which are communication is written.

somewhat globose and thicker than the central region In November, 1890, whilst searching for Rotifera, of the head. The trunk is not at all flattened, I came across, in water from a pond near Leylon- appearing circular in optical cross-section. stone, Essex, some specimens of a Dasydytes which The head is covered on all its surfaces, dorsal,

lateral," and ventral, with numerous long vibratile cilia, directed backwards.

The body is furnished, on its lateral surfaces, with a few rather short, very thin and delicate, somewhat appressed bristles, apparently arranged in about three longitudinal rows on each side, though this is a point difficult to determine. I do not think any bristles occur on the dorsal surface proper. These setä occur also on the sides of the neck, and, in side view of

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Fig. 143.-Dasydytes bisetosum.

does not appear to be identical with any member of this genus included in Dr. Zelinka's recent monograph, above referred to. Some half-dozen indivi: duals were seen in all, and afforded me opportunity of making the following observations, and of securing a fairly accurate sketch of the animal. I propose to call this Dasydytes bisetosum.

The body is plump and of oval outline when seen dorsally, rounded posteriorly, and of course without any caudal fork; 'anteriorly, the trunk narrows to the neck, which latter is very distinctly marked off from the head. A ccuple of transverse wrinkles in

the animal, are seen to be directed dorsally and posteriorly ; none are nearly so long as the terminal caudal bristles to be described. The animal's ventral surface is longitudinally furred with active cilia, like all the members of the Order. The body is rounded behind, and has a terminal projection, convexly truncate, from which are given off two long, thin and delicate setæ, quite one-third the total length of the animal's body and head, set wide apart at their base, and carried parallel or with their tips in contact. It is on account of these two conspicuous tail-bristles, which serve by their great length to distinguish this new form from its allies, that I have selected the specific title " bisetosum” for the creature.

The mouth is a permanently projecting tube, surrounded by a ring, at the extreme front of the head. It is continued into a long esophagus, about one-third the total length of the animal, having a narrow but distinct, straight lumen, and very thick walls, on which I could detect no cross-striation. The gullet terminates, at the point where the neck Metschn. These records, insignificant by themselves, passes into the trunk, in a long straight stomach, serve to indicate the probability of much more extenrunning along the ventral side of the body-cavity, sive results, if microscopic workers direct more sysand crowded with colourless food in pellets ; this is tematic attention to the study of this small and obscure continued, without any visible constriction, into the group of animals. intestine, and ends in the anus just in front of the

PERCY G. THOMPSON. rounded posterior extremity of the trunk. I could

Bow, E. not determine the presence of the water-vascular canals and contractile vesicle ; almost; certainly these exist, but are exceedingly difficult to observe.

SCIENCE-GOSSIP. Dorsally to the stomach is situated a fairly large, colourless body, exhibiting a central nuclear vesicle ; We are pleased to observe that an old and valued this body was formerly thought to be the ovary, but correspondent of Science-Gossip, and an ardent Dr. Zelinka has shown that the true ovaries in the

naturalist and botanist, Mr. T. D. A. Cockerell, Gastrotricha are paired organs placed near the venter, has been appointed Curator to the Museum, Institute one on each side of the intestine, (thus corresponding

of Jamaica, Kingston (which will henceforth be his in position with the paired ovaries of the family address). The institute is to be congratulated on Philodinadæ of the Rotifera). The large dorsal body having selected such an efficient curator. is a developing ovum ; whether this is contained within an oviduct having extremely delicate mem- The great engineer, Sir John Hawkshaw, died in branous walls, or simply lies freely in the perivisceral his eighty-first year on June 2nd. cavity, is doubtsul ; as also is its mode of exit from

PROFESSOR ROBERTS-AUSTEN has discovered the the body. The creature swims actively with an even gliding

most brilliant-coloured alloy yet known. It is of a

rich purple colour, and has bright ruby tints when motion through the water ; in no case did I observe

ligh is reflected from one surface to another. It any jerking or springing, the weak body-spines being

consists of 78 per cent. of gold, and the rest aluprobably useless for such a mode of progression.

minium. The head is often freely moved up and down upon the neck, but has not the constant drooping appear- The science of geology has received royal recog. ance (in side aspect) noticeable in D. fusiformis. nition. The Director of the Geological Survey of The lateral lobes seem capable, to some extent at the United Kingdom has been made a Birthday least, of being protruded or retracted at the creature's

Knight, and is now Sir A. Geikie. will; at certain times, the outline of the head appeared quite conical, or very faintly five-lobed (cf. the PROFESSOR LEIDY, the well-known American figures), while at others, the same animal presented

naturalist, author of the “Rhizopods of North the distinctly three-lobed outline of the head already

America,” is dead. described.

At a recent meeting of the Linnæan Society, Mr. The present species approaches in its general

Robert Deane exhibited specimens of the rayless outline D. longisetosum (Metschn.), but is at once separated from the latter by the relative lengths of

daisy, said to grow abundantly near Cardiff. Will

some reader there send us a specimen ? the body and caudal bristles. The latter are, in longisetosum, shown much less than half the We have received the “Report of the Felsted length of the lateral body-setæ (which are described School Nat. Hist. Society for 1890." It displays a as “very long and stout,”) and altogether lack the

healthy, active, and intelligent love of natural science, conspicuousness they attain in bisetosum. The pre- and indicates a state of things the author endeavoured sent form is also nearly twice the size of Metschni- to realise in “The Playtime Naturalist.” koff's species, and other differences exist which I think fully justify me in regarding bisetosum as

The latest Bulletins issued by the U.S. Dept. of specifically distinct.

Agriculture are Nos. 7 and 8 of “Insect Life," and The entire animal is quite colourless ; length,

No. 24 “The Ball. Worm of Cotton," by F. W. excluding caudal setæ, about to inch.

Neally. In conclusion, the same pond has furnished me, on

Bishop MITCHINSON'S papers in “Nature Notes,” other occasions, with specimens of Dasydytes fusi

on “The Distribution of Rare Plants in Britain," formis, Spencer, and Lepidoderma rhomboides, Stokes,

are very suggestive. (the latter only recorded, hitherto, from Trenton, New Jersey), while at Chingford I have met with We are pleased to call attention to a highly Dasydytes goniathrix, Gosse, and D. fusiformis, important brochure by the Rev. H. A. Soames, Spencer. Within the last few weeks, at Oakley, in F.L.S. (London: L. Upcott Gill), on ** The ScienBedfordshire, I have taken Chætonotus Schultzei, tific Measurement of Children." The author rightly

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