have hitherto been referring. By this memoir, entitled 'Contributions to an Insect Fauna, of the Amazon Valley,' Mr. Bates has established for himself a high rank among original investigators, and has shown powers of observation of which he may justly feel proud. For although the subject of recurrent form, or analogical resemblance, or homomorphism, or by whatever title it may be called, has attracted the attention of many naturalists, the manner in which it is here illustrated in the Heliconine group of butterflies, is equally original and acute.

Mr. Bates found that certain butterflies, so closely mocked certain others belonging to distinct groups, that though always on the watch, it required all his caution to distinguish them.* He believes that these resemblances are intended as a protection to otherwise defenceless insects, by deceiving insectivorous animals, and presumes that, seeing the excessive abundance of one species and the fewness of the individuals of the other, that the Heliconide is free from the persecution to which the Leptalis is subjected; and he seems inclined to attribute less to community of habit than we should be disposed to do, though it cannot be denied that such community is a constant concomitant of mimetism.

The bearing of this subject, upon the origin of species, is plainly

The Heliconidae appeared to him to be the objects mocked, because they all have the same family facies, whilst the analogous species are dissimilar to their nearest allies,-permitted, as it were, to produce the resemblance from the normal facies of the genus or family to which they severally belong. So close were the resemblances that Mr. Bates was never able to distinguish the Leptalides (Pieridae) from the species they imitated, without close examination after capture. And yet the Leptalides belong to a family totally different in structure and metamorphosis from the Heliconidæ, which they imitate. Moreover, they fly in the same part of the forest, and generally in company with the species they mimic. Species of Ithomia (Heliconida) concerned in these imitations have all the character of true species, being distinct and constant. They are all excessively numerous in individuals, swarms of each kind being found in the districts they inhabit. The Leptalides are extremely rare; they cannot be more than as one in a thousand of the Ithomiæ. Moreover, none of these Leptalides have been found in any other district or country than those inhabited by the Ithomiæ, which they counterfeit. A species very closely allied to L. Lysinoë has been received from Mexico; but an Ithomia of nearly the same colours (I. Nero) also inhabits Mexico. Some other Leptalides exist which do not mimic Ithomie, but some other genera of the same family, as Methona and Mechanitis. "A similar series of mimetic analogies occurs in the Old World, between the Asiatic and African Danaida (or representatives of the Heliconida) and species of other families of butterflies and moths; but no instance is known in these families of a tropical species of one hemisphere counterfeiting a form belonging to the other." So, also, on the banks of the Amazons parasitic, bees and two-winged flies mimic the dress of industrious and nestbuilding bees peculiar to this country, at whose expense they live, in the manner of the cuckoo.

An examination of the beautiful coloured plates in the Linnæan Society's memoir shows that the mimetic resemblances exhibit a minute and palpably intentional likeness, which, as Mr. Bates expresses it, is perfectly staggering; and no wonder, indeed, that he was constantly being deceived by them. Comparing Leptalis Theonoë with Ithomia Flora, or the Ega variety with Ithomia Illinissa, Leptalis Amphione with Mechanitis Polymnia (both var. Egaensis), and, again, Leptalis Orise with Methona Psidii, we cannot fail to be astonished at the closeness of the resemblance, particularly when taken in connection with the normal form of Leptalis Nehemia.

stated by Mr. Bates, as a most beautiful proof of the theory of natural selection, by showing that a new adaptation, or the formation of a new species is not effected by a great and sudden change, but by numerous small steps of natural variation and selection. Local conditions favour the increase of one or more varieties in a district at the expense of the others, the selected ones being different in different districts, in the case of the varieties of Mechanitis. "With the mimetic species Leptalis Theonoe the case is different. We see here a segregation of local forms similar to that of Mechanitis Polymnia; but we believe we know the conditions of life of the species, and find that they vary from one locality to another. The existence of the species, in each locality, is seen to depend on its form and colours, or dress being assimilated to those of Ithomia of the same district, such assimilation being apparently its only means of escaping extermination by insectivorous animals." And indeed the abundance of the mocked species seems to show that it possesses some such immunity, and at all events lives under conditions very favourable to its increase and preservation. To exist in a certain locality, a Leptalis must wear a certain dress, and those of its varieties which do not come up to the mark are rigidly sacrificed.

It is manifestly impossible in a review to enter fully into all the arguments of the work. All that can be done is to indicate the salient points, and abstract the conclusions; and much as these speculations of Mr. Bates have interested us, we must content ourselves with this imperfect résumé of them, and refer those who would know more upon the subject to the memoir itself. In taking leave of Mr. Bates, however, we cannot help expressing the gratification and rare pleasure we have felt in the perusal of his Naturalist on the Amazons,' in which a vast amount of truthful and original information is given, in an unobtrusive and unselfish style. The world of naturalists is under a heavy obligation to him for his toilsome and laborious collection of facts, and for the interesting, though probably not less laborious, work in which they are permanently embodied. Nor must we omit thanks to Mr. Darwin, for screwing Mr. Bates's courage to the sticking place, without which perhaps the work would never have been written, or at all events have been so deferred as to impair its value. The 'Contributions to Insect Fauna of the Amazons' are an important addition to Entomological science, and however averse some may be to the theory of natural selection, no one can fail to be instructed, as well as interested, by the ingenious remarks with which Mr. Bates preludes the systematic part of the subject. We hail Mr. Bates as a worthy naturalisttraveller, and willingly and gratefully accord to him a well-earned and high position amongst those who have advanced science by patient, earnest, and original investigation.

THE GREAT METEOR OF 1863.*

AMONGST the most startling of cosmical phenomena are the occasional appearances of Meteors of extraordinary size and luminosity. Coming without the forewarnings of gathering clouds and dropping rain, their sudden advent in a clear bright sky excites more astonishment in the common observer than the most vivid lightning, while the dull booming sound which follows their disappearance or explosion has more of mystery, and excites more terror than the pealing thunder which succeeds the electric flash.

Almost as transient as

"the borealis race

Which flit ere you can trace their place,"

the scientific observer is often as much at a loss to tell whence they come and whither they go as the ordinary witness of their brilliancy. He is generally but conscious of a momentary flash of light, and on looking to the heavens sees only the trail, something like a luminous scratch in the sky, left by the passing object. A debt of gratitude is therefore due to any philosopher who, like the author of the opuscule we notice, is at the pains to collect and compare the observations of any single example made at widely distant stations, and construct from the whole a connected narrative.

On the evening of the 4th of March, 1863, at about seven o'clock, Dr. Heis, Professor of Astronomy and Mathematics in the Royal Academy of Münster, was taking a walk in the open air. The sky was clear and bright, when suddenly the whole neighbourhood was for a moment lighted up as with Bengal fire, and looking upwards the Doctor saw passing majestically across the firmament a fire-ball which seemed to increase in size until it grew as large as the moon at full. Such an appearance of course excited astonishment in all who witnessed it, and as the author was known to take an especial interest in these phenomena,† a few days brought him numerous communications on the subject. From these, some contributed by astronomers and physicists of great repute, as Baumhauer of Amsterdam, Quetélét of Brussels, and Mr. Greg of Manchester, others from writers of no scientific repute, but as country clergymen telling no doubt truthfully what they believed they saw, and also from the results of his own inquiries among the most stupid of Belgian peasants, the author has drawn up this complete account of the form, apparent size, colour, brightness of the object, as well as the trail, and the manner in which it disappeared or exploded.

*Die grosse Feuerkugel, welche am Abende des 4 März, 1863, in Holland, Deutschland, Belgien, und England gesehen worden ist.' Von Dr. Ed. Heis, Professor der Mathematik und Astronomie an der Königl. Akademie zu Munster. Halle H.W. Schmidt. 1863.

The large fire-ball which was seen in Holland, Germany, Belgium, and England on the evening of the 4th of March, 1863, &c. &c.

† He had published an account of the large Fire Ball seen in Germany on the evening of the 4th December, 1861.

The Meteor appears to have been visible over a hexagonal area, the angles of which are formed by the following places:-Manchester, Brighton, Trêves, Erbach, Hanover, and the North-coast of the kingdom of Hanover. This space encloses more than 100,000 English square miles. The most distant opposite angles in the direction N.W. and S.E. are Manchester and Erbach, 553 miles apart; and from N.E. to S.W. Bremen and Brighton, 401 miles distant.

About the time of the appearance and its duration there is little room for difference of opinion. The author calculates the mean time for Münster at 7h. 6m., and the duration is variously stated to have been from 3 to 6 seconds.

The form and size of the fire-ball are naturally open to wider differences of opinion among the observers, but in this instance the differences are capable of reconciliation. One observer compared the head of the Meteor to the head of a fish, and remarked that it progressed with the movement of a swimming fish. Another compared it to a club, the length of which was three times that of the breadth. The majority observed that it was pear-shaped, egg-shaped, or figshaped; hence the author concludes that it was really ellipsoidal. But as most on the Belgian side described it as a "fiery cannon ball," the author infers that the longer axis was directed towards that side.

The apparent size was mostly compared with some terrestrial object. It was said to have been the size of a man's head, a child's head, a hen's egg, or a ball 4, 5, or 6 inches in diameter. Many said it was the size of the moon, others that its diameter was 1, 1⁄2, or that of the moon. One observer describes it as four times the size of the evening star, and another says that at its first appearance it was no larger than ordinary star dust (Šternschuppe).

The description of the colour, also, offers some differences. Some say it was of dazzling whiteness, others, a greenish blue, while another remarks that the light resembled that of the Electric spark.*

The colour, however, appears to have been changed by intervening media, so that at some stations it was said to be red, deep yellow, dark red, or violet. The author believes that the real colour of the Meteor was red, inasmuch as it appeared of that colour when at a great height, and in bright moonlight.

The most extraordinary brightness was remarked everywhere; it seemed like the sudden appearance of a full moon in the heavens. Near Boppard, an observer on a mountain saw for a moment the valley of the Rhine lighted up as by a very bright full moon. At one place, a clergyman could distinguish the letters in a newspaper lying on his table, and at Eupen a man could see to read in the street. The shadows of objects were thrown remarkably sharply and well defined; and the confused dance of the shadows of houses and trees, projected as

*The Reviewer, who was passing along Regent Street, London, on the evening in question, was much startled by the sudden appearance of an extraordinary light, which, to him, appeared exactly like the light of the electric spark. On looking to the sky, he saw nothing but a brilliant line of light which appeared to lie nearly East and West, and seemed three or four yards long.

the Meteor darted over the "Domplatz" of Münster, formed a most peculiar sight.

The Meteor was seen through the large western window of the Cathedral of Münster (as is shown in our illustration), by an observer within the building, and this appearance furnished the author, as we shall presently see, with the most important elements from which to determine its height and direction. So near to the earth did it appear at Münster, that people ran to the common before the Castle to find it, thinking it must have fallen on that spot. It was sought for by the peasantry in many places, and in one, as we shall see, by the author himself; and we are by no means astonished to read that at a village near Trêves, the peasants said that a fiery cross had fallen from heaven.

Appearance of the Meteor passing the west window of Münster Cathedral.

As is usually the case, the fire-ball of the 4th of March left behind it a line of light which showed for a few moments the direction it had taken. By some, this is described as a simple straight line of light, and by others, as a trail of sparks. One clergyman, however, denies that it left a trail, and the author accounts for the invisibility by showing that from the geographical position of the observer, the trail must have been covered by the object itself.

The disappearance is variously described by different observers. In most places they agree that the Meteor suddenly appeared and as suddenly disappeared, like lightning. But some assert, that it gave off sparks and burst like a rocket; others say that it burst into small pieces, which seemed to be entirely consumed, while one declares that it disappeared in blackish vapours, which the author does not appear to believe.

In general it has been remarked that the apparent extinction of an object such as that we are describing, has been attended by a noise resembling distant thunder. It has invariably been heard when meteoric stones have subsequently been found. No fragment of the fire-ball of the 4th of March has yet been traced, but it is certain that observers, far and near, say they heard a noise. It was not heard in large towns, even when they lay near to the spot at which the ball disappeared; but that can be easily accounted for. In some places the sound is said to have resembled the rushing noise made by a rocket in its flight, or a passing cannon-ball; in others, it is compared to the dull bump' which follows the fall of a heavy body on soft earth. We must remark, that the noise waa heard loudest in North Brabant, and appeared most distant at Hanover, from which important consequences follow.

Respecting the true path of the Meteor, the observations which reached the author left him in no doubt. All the observers in the east saw the object towards the west, going from right to left; while those in the west saw it towards the east, and going from left to right