across them they have made no effort to escape from my open hand-even when placed upon the earth have made no haste to seek cover. The pretty dormouse (Muscardinus avellanarius) finds many a snug retreat in the woods hereabout, and of course

Fig. 72.-Nuthatch (Sitta Europaa).

the domestic mouse (Mus muscules) abounds. Our lane, too, can boast of more than its complement of toads, frogs, and slow-worms, and not long since we found a large adder that had been recently killed on the sunny open at the top of the lane *-whilst the grass-snake is common.

MR.

(To be continued.)

THE VOICES OF ANIMALS.

R. J. G. HODGSON, President of the Manchester Elocutionists' Society, recently gave an address on the above interesting subject. In the mammalia the general structure of the larynx was like that of man; the power and character of the sound depending on the different degrees of development of the vocal cords, and the peculiarity of structure of the vocal organs. All animals had their characteristic voices and calls, in more or less distinct intervals and varied degrees of compass. The timbre or quality of voice was remarkably distinct in the different classes of animals, so that a mistake could not well be made. It also varied in

These snakes are particularly abundant in certain unfrequented spots.

those of the same class; the lamb could distinguish the call of its dam by the timbre of her bleat from that of the rest of the flock. Here the president showed the larynx of a sheep which he had dissected the day before. He explained the cartilages, epiglottis, and vocal cords, and noted that in this instance these cords did not meet the whole of their length, for there was an elliptical orifice in the centre. Lions and tigers with their magnitude of chest made a roar that filled the human ear with a sense of horror, as no doubt it did the ear of their prey. The depth of voice gave to the mind the idea of

an

enormous being which made children try to frighten each other with imitating the sound. The horse neighed in a descent on the chromatic scale without even omitting a semitone. It was one of the most musically-voiced of mammals; and the imitation was very difficult. The ass brayed in a perfect octave, beginning with a modest whistle, and, as the poet said, "sings in sonorous octaves loud and clear." Haydn had copied one of its ejaculations in his seventy-sixth quartette with great success. The bark of a dog was an instance of an acquired voice by domestication, much in the same way as the trotting of the horse was an acquired movement. In a state of nature the dog whined, howled, or growled. Columbus found that the dogs he had previously carried to America had lost their bark. As with many animals, the dog was capable of showing difference of feeling-the shepherd's dog gave the sound of command to the flock, while a horse knew from the bark whether the dog would bite his heels or not. Humboldt said the howling or preacher monkey of South America could be heard two miles, which was due to certain pouches connected with the larynx and to a drum-like develop. ment of the hyoid bone. An ape, one of the Gibbons, produced an exact octave of musical sounds, ascending and descending the scale by half-tones, so that perhaps it alone of brute animals might be said to sing. In the elephant house at Belle Vue Gardens there were several small monkeys with pleasing singing voices. It seemed a pity that the meek-looking and beautifully marked giraffe, that reached in one case that he had seen a height of 17 feet, should be voiceless, yet it and the armadillo had no vocal cords. The chirp of the long-eared bat was said to be the most acute sound produced by any animal. Only five out of six people could hear it. In reptiles the larynx was in a rudimentary condition, and the vocal organs showed considerable divergence. The

crocodiles and caymen made a feeble roaring sound. One kind of frog had a sound bag at each side of its mouth that acted as a resonance chamber. This must have been the case with an African frog he had heard at the distance of about 100 yards. It made a noise like a loud barking. The tortoise gave a mere snuffling sound. Snakes had no vocal cords; they only produced a hissing sound by driving air through the narrow opening of the glottis. Most fishes were mute, yet it was said the mackerel was an exception, for when taken out of the water it made a moaning sound, caused by the friction of the bones of the larynx. Insects, such as crickets, grasshoppers, and bees, were considered by the French naturalist, Goureau, to be more musicians than singers. Most of their sounds were caused by the friction of their wings together, or their legs against their bodies, or by the rapid vibrations of their wings in flying; and in bees and wasps the sound might be increased by the air passing rapidly through the thoracic air holes. Dr. Carpenter said that "in Brazil there was a grasshopper that could be heard at the distance of half a mile, which was as if a man with a big voice could be heard all over the world."

NOTES ON NEW BOOKS.

INTRODUCTION TO THE STUDY

AN OF BOTANY, by E. Aveling (London:

Swan Sonneschein & Co.). Although students of plants need not fear for lack of good manuals, there was some room for such a work as Dr. Aveling has produced. It is laid on new and original lines of treatment, and is a capital introduction to the study both of plants and plant-life. Dr. Aveling here proves himself a thorough teacher-a rôle which requires something more than mere technical knowledge, however full and thorough. His style and manner of treatment of his subject are as simple as it is possible to be. The illustrations are numerous, and mostly original. We cordially recommend Dr. Aveling's manual to all those who are anxious to familiarise themselves with the fascinating science of Botany.

Botany, A concise Manual for Students of Medicine and Science, by Alex. Johnstone (Edinburgh and London: Young I. Pentland). This is another new work on the same subject, treated, however, in a somewhat different manner-that is, in the shape of concise notes and summaries of the chief subjects of botanical science. Mr. Johnstone's book is a kind of "illustrated digest," and is therefore very useful for reference or memoriter suggestions. It contains one hundred and sixty-four illustrations, besides a numerous series of floral designs. Students will find Mr. Johnstone's little work of great use to them.

The Medical Annual, 1891 (Bristol: John Wright). The present is the ninth issue of this increasingly useful book. It includes among its contributors the

best medical writers of the day. The articles deal with the latest discoveries and subjects relating to every department of surgery and medical science. This year's Annual contains thirty-six original papers, on as many subjects, by various authors. There is also a medical, hospital, and asylum directory, and a large miscellany of information useful to medical men.

The Fishes of North America (New York: Westermann & Co.). We have received the first part of this work, dealing only with fishes "caught on hook and line." The two full-sized coloured plates are fine examples of oleographic art. The wood engravings, letterpress, and paper are superior, and altogether this work (which is to consist of forty parts) will be about the finest yet published on the subject. The two coloured plates represent the redspotted Mascalonge (Lucius masquinongy), and the Rocky Mountain Trout (Salmo mykiss). We will duly apprise our readers of the further issues of the parts of this magnificent work.

AN INTRODUCTION TO THE STUDY OF BRITISH DIPTERA.

THE

By E. BRUNETTI. [Continued from p. 55.]

BRACHYCERA.

HE Brachycera are more stoutly built than the Nemocera; the legs are shorter and thicker; the antennæ apparently of only three joints, never flexible (except in Xylophagida); the veins in the wing are less numerous and more reducible than those in the Nematocera to a type form; the alulæ are large; the palpi one or two jointed; the anal cell in wing closed.

The larvæ are aquatic or terrestrial, some feeding on animal matter, some on vegetable, principally when either is in a decaying state; a few species are parasitic. The flies inhabit almost every nature of habitat, and live on the juices of animals or plants.

Mr. Pasco (1880) recognises the Tabanida as the most highly developed family, in having nearly all the parts of a mandibulate mouth, placing the ŒEstridæ, in which that organ is more or less obsolete, as the lowest.

Macquart's Brachycera (agreeing with mine) is divided into three divisions (on the number of pieces composing the haustellum), named respectively Hexachata (Tabanida only-the haustellum composed of six pieces); Tetrachata (the majority of the remaining families-haustellum of four pieces); and Dichata (Louchopterida to Phorida, and the Syrphida-haustellum of two pieces).

In the short analytical tables of genera under each family, it is of course understood that only the principal ones are given.

1. Third antennal joint ringed, style or bristle, when present, always terminal; third longitudinal vein always forked.

2. Costal vein diminishing and not attaining tip of wing; scutellum generally spined: Stratiomyida.

2.2. Costal vein extended round tip of wing in nearly uniform width; scutellum rarely spined.

3. Alulæ large and distinct: Tabanida..

3.3. Alulæ very small: Xylophagida.

1.1. Third antennal joint unringed; style or bristle, when present, dorsal or terminal; third longitudinal vein forked or simple.

4. Antennal style or bristle absent, or, when present, always terminal.

5. Alulæ very large: Cyrtida.

5.5. Alulæ moderately large or small.

6. Front and crown deeply indented; eyes very prominent: Asilida.

6.6. Front and crown smooth, often elevated; eyes not prominent.

7. Third longitudinal vein forked.

8. From the discoidal cell, or from this and the posterior basal cell together, at most three veins emerge and reach the border; therefore, never more than four posterior cells present.

9. Third antennal joint without style or bristle: Scenopinida.

9.9. Third antennal joint with a style or bristle.

10. Anal cell always attaining the border, and there, either open or closed: Bombylida.

10.10. Anal cell never attaining the border, generally short and closed: Empida (part).

8.8. From the discoidal cell, or from this and the posterior basal cell together, at least four veins emerge and reach the border; therefore, at least five posterior cells present.

11. Three onychia to tarsus: third antennal joint with terminal bristle: Leptide.

11.11. Two onychia only; third antennal joint with terminal style: Therevida.

7-7. Third longitudinal vein simple.

12. Wings lanceolate: Lonchopterida. 12.12. Wings always rounded at the tip.

13. Anal lobe of wing distinct.

14. Antennæ with terminal bristle: Platypezida.

14.14. Antennæ with terminal style (Conopina): Conopida (part).

13.13. Anal lobe of wing rudimentary or absent.

15. Anterior basal cell short; posterior united with discoidal cell: Dolichopida (part).

15.15. Anterior basal cell long, reaching middle of wing; posterior separated from discoidal by a transverse vein: Empida (part).

4.4. Antennal style or bristle always present and always terminal.

16. Anal cell long.

17. Proboscis horny, long, simple, or geniculated (Myopina): Conopida (part). 17.17. Proboscis soft.

18. A spurious vein generally present, running along the third longitudinal vein; eyes moderately large: Syrphide.

18.18. Spurious vein absent; eyes very large: Pipunculidæ. 16.16. Anal cell short.

19. Posterior basal cell united to the discoidal: Dolichopida (part).

19.19. Posterior basal cell separated from discoidal by a transverse vein.

20. Proboscis and palpi always distinctly present: Muscida. 20.20. Proboscis rudimentary; palpi rudimentary or absent: Estrida.

12. Stratiomyidæ.

In the "Ent. Month. Mag." for April, 1889, I gave a list of the British species of this family, with analytical tables of genera and species.

The venation of all the twelve genera is very similar, and easily recognised.

The flies chiefly inhabit damp grass, marshes, aquatic plants, and more or less humid localities, the larvæ feeding on rotten fungi and decaying vegetable

matter.

The life-histories of some of the commoner species have been fully worked out.

There are five sub-families, divided as follows :— Abdomen of five or six segments; scutellum two-spined or bare. Discoidal cell emitting three veins: Pachygastrinæ.

Discoidal cell (or together with posterior basal cell) emitting four veins.

Species never metallic in colour; always black or green, with yellow spots or bands.

Scutellum spined (except Nemotelus).

Antennal style thin, long: Clitellarinæ. Antennal style short, blunted: Stratiomyinæ. Species always metallic; Scutellum unspined: Sargina. Abdomen of seven segments or more; scutellum two, four, or six-spined: Berina.

The Clitellarina are represented by Ephippium, Latr., and Oxycera, Mg.; the Stratromyine by Stratiomyia, Geoff., Odontomyia, Mg., and Nemotelus, Geoff.

Pachygastrina.-Pachygaster, Mg., three species; none very common. P. ater, Pz., is easily identified by the blackish basal half of the wing, whilst in P. Leachii, Curt., it is nearly all whitish; long 3 mm.

Clitellarina.-Ephippium thoracicum, Latr., is a large black fly, with long brownish-black wings, thick red pubescence on the dorsum, and a strong large spine on each side of the thorax; very rare ; Coombe Wood. It is supposed to take two years to reach maturity; long 12 mm.

Oxycera, Mg., is a genus of rather small black flies, with bright yellow spots and bands at the sides and tip of the abdomen, the first segment of which is much contracted.

They occur in the height of summer in long grass, and are most frequently met with in Dorsetshire; long 3-5 mm.

Stratiomyina.-Large flat-bodied flies, bred in stagnant water, and usually found in its proximity. Abdomen black, marked with large yellow side spots (Stratiomyia, Geoff.), or yellowish, with an angular dorsal stripe (Odontomyia, Mg.); S. furcata, F. (long 11-13 mm.), and O. viridula, F. (long 6-8 mm.), being the most common species.

Sargina.-Brilliant metallic-coloured flies, tolerably common. S. cuprarius, L., is blackish, thorax and abdomen metallic blue or green, or exhibiting both colours; wings with a brown suffusion below the stigma; legs thin, black; long 7-9 mm.

Microchrysa polita, L., is a small bright metallicgreen fly, with clear wings and black legs; common; often occurring in London; long 4 mm.

Berina.-Beris, Mg. They are smaller than Odontomyia; in two species the abdomen is reddish yellow, in the other three, blue-black; occurs chiefly in woods.

13. Xylophagida.

Two genera are British (five species), all very rare. Their flight is sluggish; the larva are wood feeders, and if more frequently searched for, the species might possibly be bred. Zetterstedt bred more than one species, I believe, in Scandinavia.

The antennæ are attenuated, and somewhat approach those of the Nemocera in appearance, Walker thinking the group a link between the two great divisions Nemocera and Brachycera.

Antennæ ten-jointed: Xylophagus, Mg.
Antenna twelve-jointed: Xylomyia, Rond.

Xylophagus ater, F., is illustrated in Walker's "Diptera," i. Pl. i., Fig. 10.

14. Tabanida.

These flies are the largest British diptera, about twenty species being indigenous; popularly known as gad-flies. The old Roman and Greek writers allude to flies which were evidently species of this group.

The attack cattle, and alighting on the back of the animal, draw blood by means of the long, powerful proboscis. The male is comparatively harmless, and feeds on the juices of flowers. They pair in the air, and frequent woods and pastures, their abundance often making certain roads impassable, as some species readily attack man. The Rev. J. G. Wood recommends smearing the face,

Fig. 73.-Stratiomyia, Geoff.

with darker bands; the wings are pale grey with tawny veins; legs tawny with black tarsi tips; long

20 mm.

T. bronius, L., a smaller species of a grey colour, with pale grey wings and blackish-grey legs, is also common; long 13 mm.

Pangonina.-Chrysops, Mg., is a black and yellow fly, with light wings, marked deeply with brown in the, those of the g being almost entirely brown; the sexes also differing in the form of the abdominal markings; long 9 mm. ; chiefly from the south coast.

Brauer in 1880 published a splendid monograph of the European species of Tabanus, his chief specific characteristics being the number, size, and direction of the bands on the eyes (coloured during life), the shape of the antennæ, and general form of the frontal stripe.

15. Leptida.

Six genera and about twenty species are British, though several others have been wrongly introduced as such. Long-bodied, large-winged, long-legged

Fig. 76.-Asilus, L.

neck, and hands with paraffin as a preventive against their attacks.

Their flight is very rapid, with a loud hum, and they occur most abundantly in the New Forest. Two sub-families are recognised, the venation being the same in both.

No ocelli; posterior tibiæ unarmed (Tabanina).
Antennæ seven-jointed.

Eyes bare: Tabanus, L.

Eyes pubescent.

Ocellar tubercle on vertex: Therioplectes, Zell.
No ocellar tubercle: Atylotus, Os. Sac.
Antennæ six-jointed: Hematopota, Mg.
Ocelli present, three (Pangoninæ).

Posterior tibia with small spine at the tip: Chrysops, Mg.

Tabanina.-Hæmatopota pluvialis, L., is a greyishblack fly marked with lighter bands; the wings are mottled grey, with light curved lines and circles; long 8 mm. ; often very troublesome to pedestrians.

Tabanus sudeticus, Zell. This species, the largest British fly, is usually mistaken for T. bovinus, L. (a much less common species in Britain). It is of a tawny brown colour, the abdomen being marked

Fig. 77.-Scenopinus, Latr.

flies of delicate structure, found in woods and shady localities, the larva living in decaying wood or in the earth.

Some species inhabit marshes and ditches. The metamorphoses of several species are known, Degeer saying they take three years to reach maturity. De Romand states that the larva has been known to fast for six months.

The venation of all the genera is similar, but the structure of the antennæ varies.

The three principal genera are thus separated :

Anal cell open: Leptis, F.
Anal cell closed.

Wings uniformly clear: Chrysopila, Meq.
Wings spotted with brown: Atherix, Mg.

Leptis tringaria, L., is a large, tawny, long-bodied fly, with long, tawny legs, and wings tinged with tawny brown; abdomen tawny, with a dorsal row of black spots; long 9-10 mm.

L. scolopacea, L., an allied species, differs in having wings marked extensively with brown; both common.

Chrysopila auratus, F., and aureus, Mg., are black flies, smaller than Leptis, with clear wings and dark brown stigma; common; long 7 mm.

Atherix Ibis, F., is a rare species, occasionally found in swarms, the clinging to one another at the end of a branch, depositing their eggs, and dying immediately afterwards; the mass gradually enlarging as fresh flies settle on it, and assuming a pear shape.

L. scolopacea, L., Wlk. i. Pl. ii. 6. L. notata, Mg., Curt. 705, (Heyschami). C. aureus, Mg., Curt. 713. A. Ibis, F., Curt. 26.

16. Asilida.

These flies are large, powerful, carnivorous insects, especially the g, forming an extensive, natural

Leptogastrina.-Leptogaster cylindrica, Deg. Easily recognised by its extremely attenuated abdomen, the short wings, and absence of onychia; long 9-10

mm.

Dasypogonina.-Dioctria rufipes, Deg., is a more stoutly-built black fly, and with pale grey wings, the two anterior pairs of legs being reddish; long 11 mm. The six British species of Dioctria are easily recognised, and appear to be most common in Sussex.

Laphrina.-Two species British; both uncommon, (I have taken L. marginata on nut in Kent.)

Asilina.-Asilus crabroniformis, L., is a large, pubescent, tawny-brown fly, with the apical half of

+

Fig. 80.-Pacrocera, Mik.

group, being very abundant in warm countries, the species there attaining very large size.

R. Desvoidy saw a species of Dasypogon with an Apis in its mouth.

Flight powerful, accompanied by a loud hum. They frequent woods, pastures, and dry, sandy situations, the larvæ living on plant roots.

The metamorphoses of most species are unknown. The venation is distinct.

Westwood figures larva and pupa of Asilus crabroniformis, L., in his Class. "Ins.," Vol. ii., Fig. 129.

Four sub-families, and 14 genera, representing about 20 species, are British.

Fig. 83.-Xylophagus, Mg.

the abdomen yellow; tawny-brown legs, spiny and hairy; yellow wings with brown border. Its flight is peculiar, settling on the ground every few yards. Linné says it attacks cattle; long 18-20 mm. Dysmachus trigonus, Mg., a smaller, greyish species, pubescent and spiny, and Machimus atricapillus, Fin., an allied species, with the legs prettily marked with tawny rings, are both tolerably common.

A. crabroniformis, L., Wlk. i. Pl. ii. 2. L. cylindrica, Deg., Mg., Sys. Bes. iii. Pl. xii. 16 (tipuloides). Laphria marginata, L., Curt. 94. Isopogon brevirostris, Mg., Curt. 153. Pamponerus germanicus, L., Curt. 46.

(To be continued.)

PROFESSOR WEISMANN'S THEORY OF HEREDITY.

ABOUT a year ago I began the first of a series of

papers on this subject, but was obliged to leave off owing to the pressure of other work. I had been struck by the fact that there had been only one or two casual references in the pages of SCIENCEGOSSIP to a subject which was more than any other