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One of the Paludina vivipara was the largest I ever took, and didn't my eyes glisten when I saw the giant crawling up the muddy sides of the stream; it was a well-marked specimen with a longitudinal measurement of 38.5 mill. and a transverse diameter of the aperture of 19 mill. Bythinia tentaculata was there in plenty.

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Valvata piscinalis was in tolerable abundance in the weeds on the bottom of the river, and also some little specimens which closely simulate it on first look, and of which I must warn the young collector, viz. baby P. vivipara; but by an old hand they can be at once distinguished, for where is the umbilicus, the peculiar twist on the last whorl as you look at it from the side of the aperture, and the old operculum? Valvata piscinalis is umbilicated distinctly, the operculum looks old and brownish, and it has a peculiar twist on its last whorl; the young P. vivipara has no, or if present, it is extremely slightly marked, umbilicus, the operculum is so thin that it can scarcely be distinguished on the body of the animal, and there is none of that peculiar twist on the last whorl. The young P. vivipara with the animals in them look very pretty things indeed, and they would make very pretty things too for the collection, because they appear to be marked with three black bands which come out well in relief; but on extracting the animal only a transparent horn-coloured and extremely fragile shell is left without the banding, for that has disappeared with the animal, it being present on that portion of the animal which is known as the mantle. As the shell becomes older, this colour is laid down in it by the free edge of the mantle from which it is secreted, and thus the characteristic markings of the adult shell is typified in the markings on the mantle of the embryo.

Several purple-mouthed Limnæa palustris were also taken, and plenty of Limnæa peregra and Limnaa auricularia with "intermediate forms " between these last two species. Limnaa peregra, vars. labiosa and succinaformis, were the most plentiful, and some specimens which cannot be told whether they are peregras or auricularias, and which is best to designate as "intermediate forms" for Limnaa auricularia seems to have been evolved from Limnæa peregra, not only because of the presence of these “intermediate forms," or mesostates, as they may be termed, but on account of the great resemblance the two species bear to one another in their internal structure, especially in the reproductive organs, where, if anywhere, the greatest differentiation would be expected. All the Limnæa have been seen floating; Mr. Wallis Kew first observed L. truncatula doing this in Lincolnshire; and I have lately had the pleasure of completing the list by observing L. auricularia doing the like.

The pretty and delicately formed Physa fontinalis was also taken; and also specimens of a small narrow and thin L. stagnalis which to me does not seem

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HE aftergrowth of Hardwood and Coniferous tree stumps is a subject of much interest to

the scientific and practical student, inasmuch as it affords us a pleasing and instructive study to master the details and explain the cause of this curious and interesting freak of nature.

That some trees of the hardwood species do grow after being cut down is well known; the roots draw sap from the soil which circulates through the root and stimulates those latent and hidden buds contained in the bark into growth, becoming shoots, and finally increasing to copse, ultimately reaching a tree none the less inferior to its parent, which may be again cut down and the same process repeated over and over again.

Now, if we were to destroy the bark, this physiological property would be entirely destroyed, hence, in regenerating copse woods, the great care of protecting and saving from injury is apparent.

Now, in the case of coniferous trees which have not this physiological property of pushing out young shoots and leaves from the felled stumps, how can they grow as formerly, is the main inquiry?

In some works, for instance, arboricultural work, the authors have fallen into the error of saying they have the power of growing after being cut down: and recently, at a society's meeting at Edinburgh, some authors positively asserted they had known several instances of isolated and other stumps continue growing for very many years after being cut down. Such assertions are entirely misleading, and have been given before the writers made themselves in the least acquainted with the life and various functions of plant-life. We have observed that hardwoods produce leaves and shoots which elaborate, the sap returning again by the bark to be converted into woody tissue, hence, no leaves, no growth, unless by a system inarching or engrafting.

Since, then, conifers are not capable of sending out shoots and leaves, they have no elaborating organs of their own; in other words, they have no lungs, for the leaves are compared to the lungs; they are the breathing organs of the plant. Then these coniferous stumps cannot possibly grow after being cut down, unless they have been previously engrafted

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nurse-tree will circulate into and through the root of the felled tree, and consequently not only keep it alive, but will live and make wood just the same as if it had been in full connection of all its parts, leaves, branches, and stem. Certainly, when the nurse-tree is removed, the stump will die.

Again, the root of the felled stump may, and in many cases will extract sap from the soil and send the same through to the nurse-tree, although the roots performed no function whatever. For instance,

the aftergrowth; they are only partly covered over, while the heart wood of the former tree has entirely disappeared and quite rotten, having a hole quite through. Numerous instances of these growths in all stages have come under my notice when thinning woods; many instances where close planting produced an aftergrowth which in after years I found nearly enclosed in the future layers of some of the larger roots.

These stumps were at one time all trees, having been cut down when about fifteen years old, and were

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living a few years ago, while the parent was over seventy years of age, and will continue growing as long as the nurse-tree lives.

A remarkably perfect specimen of this aftergrowth was exhibited by me at the S. A. B. Society, in Edinburgh, a few years ago, and obtained the society's silver medal. The same specimens were exhibited at The Forestry Exhibition in Edinburgh.

I may here mention, careless observers in going over old woodlands, where larch, spruce, silver, &c., are left, might have observed an effort on the part of the stump to produce an aftergrowth. But there being no nurse-tree to feed them, their existence is only until the elaborated sap is used which will be the first year after being cut down.

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Silver, Douglasii, nobilis, Albertania, spruce larch will produce aftergrowths quite freely also some other pines. But it seems the pine tribe have not the same property of freely growing over, although on examining any suspected specimen it will be found they are growing and making wood a little under the surface.

Again, to illustrate this more clearly, as I am anxious these growths should be thoroughly understood, suppose, for instance, that a man receives an injury, having lost so much blood thereby that it is found he has not enough to nurse the various organs of his body until more blood could be made to make up what was lost: suppose, then, all the bodily functions are quite healthy; if an opening is made in his arm, whereby more blood could be passed into his body from the arm of another man beside him, the man would recover. Now this admirably illustrates the present case before us. The tree has been deprived of its elaborating organs; it has no way of manufacturing blood (sap), but the nurse-tree performs that function for it, and supplies it with elaborated sap (blood), which not only keeps it alive, but forms wood yearly, the same as if it had been in full connection of all its functions. Nor does this exhaust my observations. Not far removed from the tree given in the illustration, I found another remarkable instance of aftergrowth. A leader from one tree had become engrafted into the leader of another tree about four feet from the stem. In this case the roots were both running in the same direction. After the tree had been cut down many years, and all the wood rotted away, I discovered that the shell of the main root, practically known as the "tapins," was alive, being fed by a nurse-tree, and had been making faint layers of wood almost unrecognisable for many years. This specimen was also exhibited.

Again, I have found numerous instances of natural engrafting among stems and branches. This might form the subject of another paper.

Now, in the first place, it is observed that, in order to produce an aftergrowth, the trees must become engrafted during life, when connected they will live on as long as the nurse-tree lives.

A slight difference takes place among hardwoods which become engrafted. They grow on as long as they are fed by the nurses the same as the Conifers. But should these hardwoods throw out leaves and shoots, as is sometimes the case, they might then continue to live, although deprived of the connection and the nurse, because then they would have lungs of their own (leaves). If they had not these, then if severed from the nurse they would die the same as would Conifers.

Ashford Castle, Galway.

ASTRONOMY AND METEOROLOGY.

By JOHN BROWNING, F. R.A.S.

ANOTHER American observatory is to be pro

vided with a very large refracting telescope; this fortunate observatory is Denver University, Colorado, which is to have a new refractor 20 inches in diameter. The expense of this is to be defrayed by Mr. H. B. Chamberlin, of Denver. The instrument will be mounted 5000 feet above sea level, that is 800 feet higher than the great Lick refractor.

It is a strange thing that none of our great capitalists should present such a telescope to one of our observatories. England is now behind every country in Europe, and, of course, immeasurably behind America, in optical means of research in astronomy.

Such great apertures should be of enormous value in photographing the heavenly bodies, and it is now evident that the future of astronomy lies entirely in this direction.

At the meeting of the Astronomical Society of France, held on July 6th, Mr. Trouvelot presented the society with a set of photographs of celestial objects made at the observatory of Harvard College, U.S., and forwarded by Mr. Pickering.

The photograph of the Pleiades is peculiarly interesting, as it shows the same curious rectilinear trails of the nebulous matter which are so strikingly visible in the last photograph taken by M. M. Henry. Really valuable photographs of nebulæ cannot be taken except with telescopes of large aperture.

There will be no occultations, eclipses, or other celestial phenomena of interest during September. Mercury will be an evening star during the latter half of the month.

Venus will be an evening star throughout the month, and will be in Virgo near to Spica on the 22nd.

Mars will be an evening star, but will be too low for observation.

Jupiter will be an evening star, and will be near Mars on the 12th.

Saturn will be between Cancer and Leo. Meteorology. This subject is unfortunately so fertile of interest that to treat it adequately would require

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The unfavourable weather has militated greatly against astronomical observations being made, so that there is less to chronicle than otherwise would have been the case; but this exceptional weather has greatly increased the interest in meteorological results.

As I was unavoidably prevented from writing my paper on Astronomy and Meteorology last month, I have given here the meteorological results of the two months, as I believe they will be found exceptionally interesting.

At the Royal Observatory, Greenwich, the highest reading of the barometer for the week ending June 23rd, was 3004 in. on Monday evening, and the lowest 29.72 in. on Wednesday afternoon. The mean temperature of the air was 54°2 deg., and 6'3 below the average. The general direction of the wind was N.N.E. Rain fell on four days of the week, to the aggregate amount of o'27 of an inch. The duration of registered bright sunshine in the week was 17.7 hours, against 14'4 hours at Glynde Place, Lewes.

For the week ending June 30th, the highest reading

of the barometer was 29'91 in. at the beginning of the week, and the lowest 29.35 in. on Friday afternoon. The mean temperature of the air was 619 deg., agreeing with the average. The general direction of the wind was south-westerly. Rain fell on five days of the week, to the aggregate amount of 2.37 inches. The duration of registered bright sunshine in the week was 299 hours, against 34'1 hours at Glynde Place, Lewes.

For the week ending July 7th, the highest reading of the barometer was 29.88 in. on Sunday evening, and the lowest was 29.31 in. on Wednesday afternoon. The mean temperature of the air was 56'4 deg., and 5'2 deg. below the average. The general direction of the wind was south-westerly. Rain fell on six days of the week, to the aggregate amount of 0·90 inch. The duration of registered bright sunshine in the week was 18.8 hours, against 242 hours at Glynde Place, Lewes.

For the week ending July 14th, the lowest reading of the barometer was 29.50 in. on Wednesday morning, and the highest was 29 94 in. on Friday morning. The mean temperature of the air was 55'8 deg., and 70 deg. below the average. The general direction of the wind was north-west. four days of the week, to the aggregate amount of 0'44 of an inch. The duration of registered bright sunshine in the week was 23 2 hours, against 26.6 hours at Glynde Place, Lewes.

Rain fell on

For the week ending July 21st, the lowest reading of the barometer was 29′26 in. on Monday afternoon, and the highest was 29.76 in. at noon on Friday. The mean temperature of the air was 59'4 deg., and 40 deg. below the average. The direction of the wind was variable. Rain fell on six days of the week, to the aggregate amount of 161 inches. The duration of registered bright sunshine in the week was 118 hours, against 107 hours at Glynde Place, Lewes.

For the week ending July 28th, the highest reading of the barometer was 29'73 in. at the beginning of the week, and the lowest 29 29 in. on Saturday morning. The mean temperature of the air was 60.3 deg., and 2'4 deg. below the average. The general direction of the wind was south-west. fell on each day of the week, to the aggregate amount of III of an inch. The duration of registered bright sunshine in the week was 34'8 hours, against 22:2 hours at Glynde Place, Lewes.

Rain

For the week ending August 4th, the lowest reading of the barometer was 29.25 in. on Monday afternoon, and the highest 30°07 in. on Friday morning. The mean temperature of the air was 56'9 deg., and 5.8 deg. below the average. The direction of the wind was variable. Rain fell on five days of the week, to the aggregate amount of 429 in. The duration of registered bright sunshine in the week was 220 hours, against 231 hours at Glynde Place, Lewes.

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