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from London, was, so far as the inhabitants were concerned, ten times that distance, I became fully initiated into all the popular superstitions arising from various natural phenomena, so prevalent in agricultural districts, and among them was duly impressed with the belief that the ticking noise heard in the house, in the still evening, was a portent of some domestic calamity ; and further, that the said ticking was produced by the little creature to which the fates (and Leach) have applied the name of Atropos. We all know how difficult it is to shake off an impression deeply rooted in childhood, and it was not until I came to reflect upon the structure of the creature, that I for a moment doubted the power of Atropos to send the country folk sighing at the trouble which its supposed ticking was sure to foretell. Mature consideration has forced me to the conviction that it is not in the power of Atropos to produce any sensible sound. The integuments of the creature are so soft that the fine wetted point of a camel's hair brush is sufficient to rupture them, and nowhere, not even in the thickened femora, is there a surface which, being sharply applied to a sonorous opposing one, coudl occasion an audible sound; even Anobium, encased as it is almost in a coat of mail, can only cause a little more than perceptible noise. I cannot imagine, therefore, how Atropos can possibly be the culprit. In the house in which I am now writing, I have far too many of Atropos in my insectroom; yet during ten years I have never heard the death-watch" there, whereas in my bed-room it is sometimes so loud and constant as to become a positive nuisance, its frequence in the latter room being pointed to significantly by the numerous drillings of Anobium in an old-fashioned bedstead. My credulity in astonishing freaks of Nature is pretty considerable; even, on ocular evidence, I will believe in the protracted existence of ancient toads in blocks of compact stone; but, as before said, until I see Atropos making certain movements, and a sound proceeding from the spot, and keeping time with the movements, I elect to discard what I now consider a deeply-rooted superstition. It seems to me possible that in the case of both Mr. Derham's and Mr. Chaney's observations an Anobium has been concealed in the same spot with the Atropos, but was not discovered. I ask your readers to take any substance of the same consistence as the head of Atropos, and try if by any means they can produce a ticking as loud as that of a watch, or any ticking at all, by striking it against a sonorous surface.

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IF you, Mr. Editor, or your readers, care to pursue

the subject of the Dodo further, the subjoined quaint description of this extinct bird, from a copy in my possession of the "Travels into divers parts of Africa and Asia the Great," of Sir Thomas Herbert, Bart., may be acceptable. The passage is taken verbatim from the earliest edition, published in 1638.

"Here [Mauritius] and in Dygarrois (and no where else that ever I could see or heare of) is generated the Dodo (a Portuguize name it is, and has reference to her simpleness) a Bird which for shape and rareness might be call'd a Phoenix (wer't in Arabia :) her body is round and extrame fat, her slow pace begets that corpulencie; few of them weigh lesse than fifty pound: better to the eye than stomack greasie appetites may perhaps commend them, but to the indifferently curious nourishment, but prove offensive. Let's take her picture: her visage darts forth melancholy, as sensible of Natures injurie in framing so great and massie a body to be directed by such small and complementall wings, as are unable to hoise her from the ground, serving only to prove her a Bird, which otherwise might be doubted of: her head is variously drest, the one half hooded with downy blackish feathers; the other perfectly naked; of a whitish hue, as if a transparent Lawne had covered it: her bill is very howked and bends downwards, the thrill or breathing place is in the midst of it; from which part to the end the colour is a light greene mixt with a pale yellow; her eyes be round and small, and bright as Diamonds; her cloathing is of finest Downe, such as you see in Goslins: her trayne is (like a China beard) of three or foure short feathers; her legs thick and black, and strong; her tallons or pounces sharp, her stomack fiery hot, so as stones are easily digested in it; in that and shape not a little resembling the Africk Estriches: but so much, as for their more certain difference I "dare to give thee (with two others) her representation."-Folio. London, 1638. P. 347.

As a later edition contains some emendations, the following extract is given from the "Fourth Im

because a glance at his description of Termes pul-pression," to which " are added (by the Author now

living) as well many additions throughout the whole work, as also several Sculptures, never before printed." Folio. London, 1677.

"This noble Isle [Mauritius] as it is prodigal in her water and wood, so she corresponds in what else a fruitful Parent labours in: not only boasting in that variety, but in feathered creatures also; yea, in the rareness of that variety: I will name but some, and first, the Dodo; a Bird the Dutch call Walghvogel or Dod Ersen: her body is round and fat which occasions the slow pace or that her corpulencie; and so great as few of them weigh less than fifty pound: meat it is with some, but better to the eye than stomach; such as only a strong appetite can vanquish: but otherwise, through its oyliness it cannot chuse but quickly cloy and nauseate the stomach; being indeed more pleasurable to look than feed upon. It is of a melancholy visage, as sensible of Natures injury in framing so massie a body to be directed by complemental wings, such indeed as are unable to hoise her from the ground, serving only to rank her amongst Birds: her head is variously drest; for one half is hooded with down of a dark colour; the other half, naked and of a white hue, as if Lawn were drawn over it; her bill hooks and bends downwards, the thrill or breathing place is in the midst, from which part to the end, the colour is of a light green mixt with a pale yellow; her eyes are round and bright, and instead of feathers has a most fine down; her train (like to a Chyna beard) is no more than three or four short feathers: her leggs are thick and black; her tallons great; her stomach firey, so as she can easily digest stones; in that and shape not a little resembling the Ostrich: The Dodo, Cacato or Parrat and one of the Hens take so well as in my Tablebook I could draw them."

This description is worthy of respect, inasmuch as it is from the pen of a well-known old traveller, who saw the ungainly bird in its native habitat; but as for the "sculpture" of the male and female of the species with which the garrulous baronet accompanies his text, one is compelled to add that, if his drawing of the pair of Dodos resembles the originals no more faithfully than that of the "Cacato [cockatoo] or Parrat" resembles that wellknown bird, his pictorial memoranda from his "Tablebook" are a "world too wide" from nature to serve any useful purpose. HENRY CAMPKIN. Reform Club.

WORK.-As in travelling so in thinking; he who has started must work with the means which he owns, however small the stock may be. There is a time for gathering such mental gear; when it is gone, the time comes for using engines or expedients. If grammar, logic, and mathematics be mysteries, the rule-of-thumb must serve their turn.-Frost and Fire.

I

PODURE.*

have often been asked by friends interested in microscopical pursuits where Podura were to be obtained, and I myself was puzzled over the problem once. Mr. Hogg's work on the Microscope, and Dr. Carpenter's more elaborate treatise, had sharpened my curiosity on the point, and I regretted I did not count among my acquaintances some one to whom I could apply for the entrée of a wine-cellar, there to put in practice the plan recommended for the capture of these insects by means of oatmeal and a basin-a plan which I was led to think would produce abundant results. Soon, at Smith and Beck's, I bought a slide of the scales, and to my great disappointment found I could not see them satisfactorily in my microscope. But there is no wonder in this, for beginners are not usually furnished at the outset with the best class of objectives, by means of which alone can the markings on this microscopic testobject be plainly seen.'

Fig. 37. Podura, without scales; common under stones.

However, though I had obtained a slide of the scales, I wanted to see a living Podura. "Surely," thought I, "if they are so common in cellars, there is a chance of their being found in the lower regions of the house in which I live." So I took a candle, and commenced a search on the outside of a beerbarrel. Peering into its seams, I soon discovered in these localities, and on the wall, tiny creatures of a leaden hue, with purplish reflections in those parts where the light chiefly played. "Can these be

* Read at the Quekett Microscopical Club, Nov. 23, 1866.

Poduræ ?" The question was soon settled in the affirmative after the examination had been made under the microscope of two or three captured specimens. The scales were, however, smaller and more transparent than those on my bought slide, and the markings far less distinct. Having paid some attention to these insects since then, I proceed to record my notes.

With regard to the habits of Poduræ, and the places where they may be successfully sought, I may say they all love damp situations. Some prefer an excessively moist condition, such as the surface of a puddle in the open country or by the roadside. These are destitute of scales, and sometimes occur of considerable size. (See figure in "The Micrographic Dictionary," page 554.) They may also be found under stones in damp places, and often are abundant at the edges of weedy ponds. Others are content with the humid atmosphere under the broad leaves of a dock, or at the roots of a dandelion; and others again show their aversion to daylight by taking up their abode under a stone, or amid the cobwebs and the darkness of a damp cellar. In these latter localities more particularly do the scale-bearing species delight.

They feed upon decaying animal and vegetable substances, such as a stale cooked potato, decaying leaves or vegetables, a rotten bone or an egg-shell. All these form capital baits. In addition I find oatmeal is moderately successful in a cellar, and an old shoe has been recommended to us as possessing special attractions. The easiest mode of capturing Poduræ, when found, is one told me by Mr. Powell, the eminent optician. A small glass tube a quarter of an inch in diameter, and about two inches long (a quill will do nearly as well), open at one end and corked at the other, is placed over the insect, which most probably takes a leap into it instantly. The open end can then be closed, and you have your prisoner safe. In order to obtain the scales I administer chloroform vapour, and then, with the side of a needle, press the Podura gently on the thin glass cover, which has been previously cleaned. I sometimes find they leap into the glass tube so violently as to die on the spot from their self-inflicted injuries.

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The Podura belongs to the order Thysanura, the characteristics of which, as extracted from the "Micrographic Dictionary," are as follows:"Wings absent; not undergoing metamorphosis; not parasitic; mouth furnished with mandibles and maxillæ; eyes simple, in two groups; abdomen mostly terminated by setæ or a bifid tail."

The Podura possesses about sixteen simple eyes, arranged in two groups, one on each side of the head. Each group, containing eight, looks like a cluster of beads.**

It would appear that some species have 14 or only 12 eyes: there is often much difficulty in counting them.

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insect finds its legs cannot carry it into safe quarters quickly enough, it suddenly straightens out its tail horizontally, thus striking a smart blow with it on the ground. The force of the blow is sometimes so great as to cause the creature to rise into the air some twelve inches or so, and then it alights in an unexpected place, whence it crawls away in security. I think a curious organ (situated between the third pair of legs), which I also saw, on one occasion, used as a sucker, when the Podura was walking in an inverted position on the under-side of the cell-cover, assists the tail in the operation. The whole apparatus bears some resemblance to the ingeniously contrived wooden toy frog, which, by means of a string, a piece of wood, and a bit of cobbler's wax, can be made to leap for the amusement of children. The antennæ are four-jointed, and the whole body is covered with a series of scales arranged very much after the fashion of those on the wings of moths. The antennæ, as well as the legs, which terminate in two claws or toes, are clothed with fine hairs, and also in some cases with scales.

My experience refers especially to two kinds of scale-bearing Podure; one of them black or leadencoloured (P. plumbea ?), and another of a fawncolour, somewhat speckled. I shall speak of it as the Speckled Podura, for want of knowing its scientific name. I do not think it has been described; its scale certainly has not, and I shall allude to it presently. The former is of frequent occurrence under some boards at the back of our house, and also in similar situations in a cellar at Brixton; the latter occurs in the same cellar, but inhabits the woodwork and the whitewashed wall, rarely being

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seen on the floor, except during the winter months. I can catch a black Podura occasionally by means of oatmeal, but have to trust to my eyes and fingers alone in the case of the speckled. Both kinds will, however, eat oatmeal when kept in confinement. I have had numbers of them both enclosed in roomy, wooden cells, and have derived much pleasure while watching their habits. The floors of the cells were covered with moistened blotting-paper, in order that the humid atmosphere in which the insects live might be imitated.

Fig. 40. Black Podura, front view, x 40.

The Black Podura* is a most superb object under the microscope, because the scales decompose light strongly; hence brilliant colours, especially purple, play over the surface of the little creature when it is well illuminated. I do not succeed well in the preservation of dead specimens. One only has hitherto afforded me a somewhat satisfactory slide: it is mounted in the dry. If fluids are used, all the scales come off directly. The application of fluid, however, enables the examination of the mode of attachment of the scales to be performed very readily.

On one occasion a fine colony of this species was found on a rotten chip of wood, and deposited in a

The colour varies much: some specimens are dull grey, and others have bronze reflections. It has been suggested to me that possibly the correct scientific name of this species is Macrotoma nigra.

deep cell for observation. They disliked their position exceedingly, and made vain attempts to get away, but ultimately accommodated themselves to circumstances pretty well. I noticed that they often cast their skins. One was observed shortly previous to, and immediately after, the operation. During the process its colour became much paler, almost white, and large drops of fluid adhered to it in various places. In the course of a couple of hours I looked again, when lo! it had extricated itself from the old coat, and was busy turning round and round in a bran new one (which was many shades darker than the old), as if to try how it fitted. The exuvid (scales, antennæ, portions of the tracheæ, &c.) were all attached to the cell-cover, which I removed in order to identify the various parts under high powers. The full size of the insect is about one-eighth of an inch in length.

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*

This family produced, while in confinement, a brood of young ones. The eggs were not noticed because they were concealed under the rotten chip of wood, but on the 18th June about twenty tiny white Podura were seen, apparently just born. They were clothed with hairs and rudimentary scales, the head was large in proportion to the body, the eyes red, and the general resemblance to the parents great. They seemed to feed greedily on the fungoid growths which had arisen in the cell, owing to the conditions existent there, and were very active. Soon they betook themselves to an oatmeal diet, and in course of time grew, so that on the 3rd of July there was little except their size to distinguish between them and the old ones. They had then acquired iridescence, doubtless by casting off their skins several times, and behaved just like their parents, running hither and thither, meanwhile

*The process has been repeatedly witnessed since then. The tail is the last part drawn out of the exuviæ. I have some now (Feb. 1), which were confined at the close of last November, and they appear to be in perfect health.

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Fig. 42. Scale of Black Podura; objective, A eyepiece.

The scale of this Podura is very like that supplied to me as the real "test scale." The markings, though clear, are much finer, and I suspect that the test scales are only found on the oldest Poduræ, but I am open to correction. Accurate information about Poduræ seems at present difficult to obtain. The adult insect should be selected in preference to the young specimen, the tegumentary appendages of which appear to me to be imperfectly developed. I notice that the small ones are more iridescent than the full-grown insects.

The other species of Podura which has come particularly under my notice is rather larger than the black species. Its colour is very light brown, often speckled with black, and there is no symptom

Fig. 43. Scale of Speckled Podura; objective, A eyepiece.

the whitewashed door, or similarly treated wall of the cellar at Brixton); but I have unexpectedly caught stray ones in other places, chiefly indoors; hence I suspect it inhabits the decayed woodwork of houses. Under the microscope, this sort displays a speckled or banded appearance-the back and sides being clothed with scales, mostly dark brown or black, arranged in transverse rows. The individual scales are exceedingly beautiful and much more easily resolved than the standard test scales. They also possess faint transverse striæ on the elevated portions. Hitherto they have seldom, if

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