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repairs done have effectually barred their exit from the woodwork of the floor. The Micrographic Dictionary says, "This active little insect, which runs, but does not jump, is found (in the country) upon the shelves of cupboards, where sweets and other eatables are kept, in window cracks, &c. Its habits are nocturnal."

A relative of the Lepisma saccharina, frequenting the rocks at the sea-side, and very like it in appearance, gives a very different scale.

The Podura scale still holds its ground as a genuine test for penetration in a good or object glass. The insect from which it is obtained is about the size of a flea, and is to be found in cellars. There are many species inhabiting various localities. I have found one sort under damp stones and flowerpots at various times, which gives tests of extreme difficulty. This species glows with iridescent colours, and is very small. Another kind, and perhaps the most suitable for the purpose of display or trial, inhabits drier places, and often, in the summer time, makes its appearance in the house, under unexpected circumstances; such as hopping on the book you are reading. It is either silvery-white

or dark-grey. Dr. Carpenter says, "Its scales are of different sizes, and of different degrees of strength of marking, and are by no means of uniform value as tests. The general appearance of their surface under a power not sufficient to resolve their markings is that of watered silk, light and dark bands passing across with wavy irregularity; but a well-corrected lens of very moderate angular aperture now suf. fices to resolve every dark band into a row of short lines, each of them being thick at one end and coming to a point at the other, so that the impression conveyed is that of a set of spines projecting obliquely from the surface of the scale like the teeth of a 'hackle.' A more careful examination of the scales, however, of which the superficial layers have been removed, serves to show that these dark lines are but the

Fig. 63. Scale of Podura x 450.

spaces between the minute wedge-like particles arranged side by side, and end to end, of which those layers are made up." The directions copied from one book into another about catching these insects with oatmeal or flour, I fear, are not of much value; at least, I never succeeded myself in that manner. I believe they may be found in every cellar or damp cupboard, and I have never experienced any difficulty in finding them.

When obtained, they must not be touched by the hand, or the scales will be rubbed off. Having induced them to enter a pill-box, the insertion into it of a little piece of blotting-paper saturated with chloroform will effectually kill them. If chloroform be not at hand, the sulphurous vapour from a lighted lucifer-match will do as well.

The writer's humble opinion with respect to the scales of insects, as tests, is, that they are invaluable, inasmuch as they show the penetrative power of the object-glass while the markings on the more difficult Diatomaceæ test its definition. In highpower object-glasses of inferior quality one or other of these requisites fails.

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Fig. 64. Scales of Curculio of the Beech x 350.

The elytra of many Curculios, British as well as foreign, are worthy of being mounted. I, like many others, have endeavoured to discover the cause of their splendour, but am unable to throw much light on the subject. The scales of both British and foreign beetles were examined, first in the dry state, both by transmitted and reflected light, and also by dark-ground illumination. With the two former modes of display the colours were strongly marked. Under a objective by Ross, and with transmitted light, rainbow tints were present in each scale, rendering it very beautiful; something like the phenomena of polarized light. This was particularly the case with the scales from the Diamond Beetle of Brazil, which resembled a piece of selenite of varied thickness under the polariscope; the different colours being quite as bright, and bounded apparently by either cracks in the surface or breaks in the lamina composing the scale, just like that mineral, or like the pieces of stained glass in a church window. When dark-ground illumination was adopted by means of the parabolic

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Fig. 65. Scales of Diamond Beetle x 450. possible cause of the resplendent glories adorning the insects in question.

I have tried the new illuminator for opaque objects under high powers (Smith & Beck's pattern) on the wings and scales of insects, and find the results are important. Surface-markings

Fig. 67. Scales of Pieris Brassica objective, with same illuminator.

made more complex, the price, which is now so reasonable, will be greatly increased.

Surely, none can contemplate the minute specimens of Divine handiwork, referred to in this paper, without a feeling of awe at the infinite skill of the Creator. The elaborate ornamentation of the scales on a butterfly's wing, which are numbered by hundreds of thousands, and in some even by millions, on a single insect, cannot be adequately copied by the pencil, and we have to be content with a general approximation.

Compared with the richness of the dress worn by these humble creatures in the scale of life, what are the tawdry gewgaws with which human beings delight to deck themselves? Look at one scale from the Diamond Beetle, and say to what jewel it can be likened; so many colours of brightest hue does it transmit to the eye.

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S. J. M'INTIRE.

Fig. 66. Damaged Scale of Morpho Menelaus, objective, with Smith & Beck's patent illuminator.

are rendered much more distinct, and appearances are presented which are quite novel. The best light is a narrow flame, obtainable by turning the lamp round, a small condenser at the proper distance between it and the aperture in the side of the illuminator, being interposed, to modify it. The objects should be mounted on dead-black paper and uncovered, and the object-glass accurately adjusted to suit this condition. The performance of the objectives is not at all impaired, but there is a certain amount of flare, due perhaps to superabundance of light, or reflections, which it would be desirable

AT

SIMPLE OBJECT S.-X I.

SPHERIA HERBARUM.

T this season of the year, and for two or three months to come, the dead stems of herbaceous plants, and small twigs from trees, will be found sprinkled with little pustules, or black dots, in many cases not so large as a pin's head, and which are exceedingly interesting microscopic objects. The majority of these little dots are minute fungi, belonging to the group known as the Sphæriacei, the structure of which we can best illustrate by a definite species, and have, therefore, selected one which is very common on herbaceous stems; whence it is named Sphæria herbarum.

First of all let us examine our object with an inch objective in situ. The little black spot is perhaps covered still by the epidermis. Later in the season the cuticle will be thrown off; now it may be necessary to remove it. The black body is nearly spherical, slightly flattened at the base, and sur

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a. Perithecium. b. Section of ditto, magnified slightly. c. Ascus, with uniseriate spores. d. Ascus, with biseriate spores and paraphyses x 320.

be made of this little black bottle (fig. 68, b), or the top sliced off with a sharp knife, the interior will be found occupied by a minute drop of jelly-this is the nucleus. Dig it out with a needle, or a sharppointed penknife, and place it in a drop of water on your glass-slide, cover it with thin glass, then press gently, at the same time moving the cover a little, so as to separate the nucleus sufficiently for the light to pass through it. Now examine your little drop of jelly with a quarter-inch power, and you will find that it is not the mere gelatine which you may have supposed. There will be seen cylindrical transparent bags, or asci, each containing eight beautiful amber-coloured spores (figs. c, d). Earlier stages of the asci will show merely a granular mass. Beside these bodies long hyaline threads will accompany the asci, which are the paraphyses (fig. d.) The asci are themselves delicate and easily ruptured, when the spores will appear scattered over the field, mixed, probably, with some perfect asci. The arrangement of spores is very variable in this species, as well as the form. In most instances they are oblong, a little narrowed in the middle, with the endochrome, or internal substance, curiously divided in a muriform manner. At first they are colourless, but, as they approach to maturity, assume a bright

amber-colour, and escape from the ascus and the perithecium, or little black bottle, through the minute orifice at its apex, in order to fulfil their mission to "increase and multiply, and replenish the earth."

Having examined this object, and being desirous of preserving the little stick with its remaining spots for examination, five or ten years hence, if need be, let it become quite dry, and put it in a drawer till you require it. When about to examine a specimen which has thus been preserved for an indefinite period, all that is requisite is to soak it in water for an hour or two (all night will do it no harm). This will render the nucleus, which had dried up, as gelatinous as ever; or, if not, then remove one of the perithecia entire, but without any adherent tissue, place it in your drop of water, break it with the point of your knife, cover, and examine as before. To mount such a specimen is easy enough. Let the water be replaced by a drop of spirit; when this has evaporated, add your drop of diluted glycerine, or balsam, dissolved in chloroform, and cover. No cells are requisite. Generally the balsam renders the asci too transparent. Glycerine, or Deane's gelatine, though not used with equal facility, is preferable in the majority of instances.

We have two hundred species of this group in Great Britain, some with exceedingly beautiful spores; and they have the advantage of being found everywhere during the dullest season in the year, and may be picked up and put in the pocket with no other apparatus than an earnest mind and a willing hand. M. C. C.

N.B. Specimen of the above will be forwarded on receipt of stamped and directed envelope, to be sent during the current month, to the office of this Journal.

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CORRECT WRITTEN DESCRIPTIONS EQUALLING PICTORIAL REPRESENTATIONS.-" Sir Walter Scott tells us, that Nature having denied Mr. Croftangry a pencil, he endeavoured to make words answer the purpose of delineation. I almost think, though fancy may be equally expansive in both cases, that if one has any general knowledge of the subject, a particular description of any of the variously-formed objects of nature would ensure as good a distinctive resemblance as if drawn pictorially from life. The only exception is the human race, in which nature, having arrived at the extreme limits of animal composition, illustrated by there being absolutely the same number and quality of the external organs in every tribe, the chef-d'œuvre of her works may, perhaps, be better expressed by portrait than by description; but all the other objects of animated nature, even in the same division, differ so exceedingly from each other-for example, in the present case, the Mollusca,-that descriptive notes may possibly be preferable to artistical representation."Clark's" British Marine Testaceous Mollusca."

THIS

Fig. 69. THE PIKE.

HIS well-known tyrant of our rippling waters needs no specific description. Not only in Great Britain, but also in most of the countries of Europe, it is far from uncommon; from Norway and Sweden in the North, to Spain and Italy in the South. It is said, moreover, to extend through the temperate regions of Asia, as far as China, and even to find a home in the rivers of North America.

Many stories have been told of its longevity and rapacity, but none more clearly indicates its ferocity when pressed by hunger, than that narrated by Mr. Cholmondeley Pennell:

"A young gentleman of fifteen years of age went with three other boys to bathe in Inglemere Pond, near Ascot, in June, 1856. He walked gently into the water to about the depth of four feet, when he spread out his hands to attempt to swim: instantly a large fish came up and took his hand into his mouth as far as the wrist, but finding he could not swallow it, relinquished his hold, and the boy, turning round, prepared for a hasty retreat out of the pond; his companions, who saw it, also scrambled out as fast as possible. He had scarcely turned himself round, when the fish came up behind him, and immediately seized his other hand crosswise, inflicting some very deep wounds on the back of it: the boy raised his first-bitten and still bleeding arm, and struck the monster a hard blow on the head, when the fish disappeared. Seven wounds were dressed on one hand, and so great was the pain the next day, that the lad fainted twice; the little finger was bitten through the nail, and it was more than six weeks before it was well. The nail came off, and the scar remains to this day. A few days after this occurrence, one of the woodmen was walking by the side of the pond, when he saw something white floating. It was found to be a large pike in a dying state, and he brought it to the shore, and the boy at once recognized his antagonist. The fish appeared to have been a long time in the agonies of death, and the body was very lean, and curved like a bow. It measured forty-one inches. There can be no doubt the fish was in a state of complete starvation. If well fed, it would probably have weighed from thirty to forty pounds."

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The maximum size and weight to which a pike will attain has not been satisfactorily determined. Mr. Pennell states that he can easily refer to many attested examples of pike having been taken in the British islands, up to the weight of 70, 80, and 90 lbs. Colonel Thornton refers to one taken from a sheet of water at Lochaber of 146 lbs. ; and Sir John Hawkins mentions one taken in 1765, which weighed 170 lbs. Block states that he once examined a portion of the skeleton of a specimen which measured 8 feet.

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What is the duration of the life of a pike, is still an open question." That it will attain a great age is certain, but whether it will live, as is narrated of the Kaiserwag pike, for 267 years, is not so readily assented to. It will most probably vie with man in the duration of its existence, for Pennant alludes to one which was 90 years old.

A curious little creature may be seen roaming at will over the body of a pike, even when confined in an aquarium; and if this parasite is only as troublesome as some which delight in the human body, then the life of a pike is not altogether one of unmixed serenity.

Argulus foliaceus, for so the parasite is named, is

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It has been found also on the stickleback, carp, roach, trout, perch, and even upon the tadpole of the common frog. Not having space to enter upon the description of this crustacean here, we must refer the curious to a very interesting account in Dr. Baird's "British Entomostraca," pages 242-256. The microscopical student will find good employment for his instrument, not only in the examination of the Argulus, but also in the scales of the pike, which, although not so attractive as those of the sole and the perch, are yet well worthy of being secured and mounted for the cabinet. The structure

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is entirely different in its character, and whether viewed by ordinary illumination or by means of polarized light, is far more beautiful than any simple woodcut, be it ever so truthful, can represent. We must now bid adieu to the august individual whose portrait surmounts this notice, hoping, that when next we meet, it may, for us, be under happier auspices; that, instead of the shadow, the substance, smoking and garnished, may appear on the table which now supports the record of his name.

AT

FALLS OF THE ZAMBESI.

T the meeting of the British Association, Dr. Kirk gave the following general account of these falls. Compared with Niagara, the falls are twice as deep, and, being a mile wide, are perhaps grander even than those falls, but the mass of water is much less. At the low season he had seen natives wade from the northern side to the first bank, but the remainder is always very deep. The river rose 16 feet in the rainy season; and seen at that time, the cataract must equal in volume the great Niagara falls, all the little rocks on the edge being then wholly submerged. As the length of the falling sheet of water in one place alone would be more than a quarter of a mile, tumbling in one unbroken mass, the sight must be of a most sublime character. In the central island Dr. Livingstone planted a garden; there were some peach and other trees; but he could not find any remains of them when he went to the spot, as the place had been visited by a hippopotamus. -Hardwicke's Report of British Association.

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