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not the acidity of the

sap that ripens the leaf, but rather the ripening of the leaf that acidifies the sap. If this be so, the cutting off of the supply can have no effect one way or the other, except it be to precipitate the death of that part of the leaf, which would scarcely be to the advantage of the insect. I have thought much over the matter, I have furbished up my rusty physiology, I have looked at hundreds of leaves, hoping for a ray of inspiration, I have even made a mild experiment or two, and the only conclusion I can come to is, that it depends on one or other of two things, or to speak more correctly on two forms of one and the same thing. This I believe to be irritation; either mechanical, that is, due to the simple presence of the larva, or chemical, owing to some special product or secretion emanating from him. And I further think that both forms may occur-in one case the mechanical may prevail, in another the chemical.

The Nepticula are not the only insects that have this power. It is possessed, I am inclined to think, in a greater or less degree by every creature that lives within the tissues of a leaf. Should you, in passing under a beech grove late in the year, pick up some of the dead brown leaves, you will probably find projecting from their surface certain little round swellings; these are galls, and if you look carefully, you will see that each is surrounded with a narrow zone of living green tissue. This I should consider an example of purely mechanical irritation. Again, there is a group of small moths, the Lithocolletis, that make very curious mines, quite different to those of the Nepticulæ, for they mark out at starting the exact quantity of the leaf they will require. Up to this boundary the ripening process advances from all sides, and there abruptly stops. This too, I think, is mechanical irritation. In the case of the Nepticula the patch preserved is never mapped out in this definite fashion, but the margins, except where they happen to be bounded by a rib, fade out gradually into the brown parts, and it is almost impossible to escape the conviction that it is produced by the spreading of some liquid that gets more and more diluted the farther it extends. This is what I mean by chemical irritation, for I am of opinion that there is some stimulating material, either poured out of the mouth of the larva or perhaps contained in its frass, which being taken up by the sap soaks through from cell to cell, stimulating them in its progress and getting more diluted and attenuated the farther it travels. I only regret that the backward autumn does not allow me to show you specimens. Could I have brought you aspen leaves holding the larvæ of apicella, they could not have failed to excite your admiration. You would have seen a large fan-shaped splash of bright green running right across the leaf from stalk to margin, whilst all the rest was yellow; and you can imagine how striking the effect must be, when, as I have more than once known it, almost every leaf on the tree was in this condition. The rare species intimella, in the same way, will keep one lateral half of a leaf of the Bedford Willow green long after the other half has changed first to yellow and then to brown. Both live at first in the leaf stalks of their respective plants, and it is only late in life that they enter upon that still living portion of the blade they have so cunningly provided for themselves. Even should the larva die whilst in the stalk, the green splash will occur just the same. Again, you will often see the little green patches of subbimaculella in the brown

oak leaves, lying on the ground in October and November. The larva is a blotch miner, but he first runs a very fine gallery choked with frass close alongside the mid rib, to catch as it were the sap just as it leaves the vascular bundles, and impregnate it, as I suppose, with the stimulating agent; the whole virtue of the process too seems to lie in this preliminary gallery, for should the larva die at this early stage, the green patch is still there, as green and fresh as if nothing were amiss. It was a consideration of facts like these, that made me conclude that there must be some peculiar substance, either secreted for the purpose by the larva, or else existing, and this seems to fit the condition best, as one of the natural constituents of its frass.

Without this adaptation between the insect and the plant, without this benificent provision that I have feebly tried to represent to you, many of these little creatures would cease to exist. Shall we say that this is all blind chance and not Infinite Design.

I seem quite to have forgotten that the heading of my paper is "The Nepticula of the Woolhope District." Suffice it to say that in one small corner of that district, with a radius of about one and a half miles, no less than 50 out of the 70 British species occur, besides which there are three or four species that I have only met with in the larval state, and from their extreme scarcity have hitherto failed to rear-but I must succeed some day, and perhaps one or two of them may want a name.

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ruficapitella.

pygmaella.

pomella.

oxyacanthella.

pyri. I first found this in 1889. It had not been found in Britain before, and is still, so far as I know, confined to Herefordshire. It feeds on pear, and is sparingly distributed in our orchards. viscerella.

anomalella.

aucupariella. Confined in this neighbourhood to Haugh Wood, where only its food-plant, Pyrus aucuparia, grows in any quantity and in a truly wild state.

desperatella. Added to the British Lists from specimens taken here in 1886. Has since been met with in the North of England. Feeds on wild apple, and is plentiful but local in Woolhope District. More gregarious in its habits than Nepticulæ generally one bush being full of its mines, and an adjacent one empty.

catharticella.

basiguttella. Reckoned a scarce species, and occurring chiefly in the Eastern Counties. Widely, but sparingly, distributed here.

septembrella.

14. Nepticula intimella. A rare species in most places. Occasionally abundant in the larval state here. Feeds on both Salix caprœa and Salix russelliana; its habits being somewhat different in the two plants. subbimaculella. apicella.

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trimaculella.

assimilella. Very rare. First recorded as British in 1885 from

specimens bred in Sussex.
uncommon at Haugh Wood.

Confined to aspen, and is not
Elsewhere, as at Ashperton Park,

though its food-plant may be plentiful, it is absent, or nearly so.

salicis.
diversa.

Little known as a British insect. Its larva occurred here in some plenty four or five years ago, in the leaves of Salix capræa, but has scarcely been seen since. This irregularity of appearance is a strong feature among many of the Nepticulo. myrtillella. At Haugh Wood, in the bilberry leaves, but not plentiful. A remnant probably of a former moorland fauna. floslactella.

sorbiella. Confined like aucupariella to Haugh Wood, and for the

same reason.

lapponica.

luteella. "9

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arcuatella.

angulifasciella. On various roses, specially fond of Rosa arvensis, I have also found it on Poterium sanguisorba, a most unusual food, and strongly suggestive of its being a distinct species; but there is no appreciable difference between these larvæ or the moths bred from them and ordinary angulifasciella. atricollis.

microtheriella.

argentipedella.

Woolhopiella. Discovered in 1887. Has since been found commonly in the North of England.

betulicolella.

distinguenda. A little known insect. Taken in the North of England, and at one time not uncommon here, especially at Ashperton Park on the "Old Red," but not seen for the last two years. Feeds on birch.

plagicolella.

malella.

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tityrella.

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fulgens. A new species described by Mr. Stainton in 1888 from North of England specimens. It feeds on beech, and is not uncommon here.

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prunetorum. Very common on the sloe bushes along the limestone
ridges of the district, but almost absent from the valleys.

regiella.
torminalis. Discovered in this district, and described as a species
new to science in 1890. Food plant Pyrus torminalis. Rare,
and extremely local; confined to a small corner of one wood,
although the Pyrus is distributed universally.

continuella.

alnetella.

marginicolella.

ulmivorella. The scarcest and most uncertain of the elm species.

At the present moment it has almost disappeared.

æneofasciella. Specimens bred from Potentilla tormentilla are much smaller and less richly coloured than the type, bred from Agrimonia eupatoria.

splendidissimella. Probably a variety of aurella.

gei. Also no doubt a variety of aurella.

aurella.

dulcella.

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AN INCIDENT IN THE HISTORY OF THE EIFFEL

TOWER.

By the Rev. J. O. BEVAN, M.A., F.G.S., Assoc. Inst. C.E., Vicar of Vowchurch.

CHANCING to be in Paris in the year 1889 at the time of the holding of the International Exhibition, I witnessed a phenomenon of a remarkable character, which was noticed cursorily in the French papers at the time; but, so far as I know, has not found a permanent record in the pages of any English scientific journal. I therefore venture to hope that a brief description of it may not be unsuitable to the pages of the Transactions of the Woolhope Club. The occurrence to which I refer was nothing less than the striking of the Eiffel Tower by lightning. It took place on Sunday, August 25th. After dining at my hotel, I wandered out for a stroll in the Champs Elysées. About eight o'clock a thunderstorm unexpectedly broke out accompanied by torrents of rain. Being unprovided with wraps, I ventured to seek shelter under the archway of a public building bordering the main drive. I remained there for the hour during which the downpour lasted. The position I had taken up commanded a full view of the Tower. It was impossible to regard this object without a peculiar feeling of fascination. Its novelty, its graceful outline, its giant frame towering above the multitudinous Exhibition buildings, the powerful electric light at its summit enabling a newspaper to be read by its aid at a distance of some miles-all conspired to render it of singular interest. Furthermore, I had a presentiment that its majestic form could not remain altogether unaffected by the warring elements. I had been watching it for at least a quarter of an hour, when the heavens above opened, a stream of fire issued, and (taking a slanting and somewhat irregular direction) smote immediately upon the apex of the Tower. The appearance presented was as if a reel had been suffered to drop-one end of its fiery band being fixed at a point in the heavens-the reel descending (unwinding as it fell) until at last it struck the summit. This reached to a height of 300 metres (about 984 English feet), and terminated in a pointed rod or lightning conductor. The Tower received a shock, the extremity of the conductor was fused, the iron hail falling upon the engineer who chanced to be beneath. There were about two hundred persons on the various stages when the occurrence happened. They were more frightened than hurt. To keep up appearances, two or three ladies fainted-that was all. The Tower, being formed of iron, permitted the electricity to pass freely to the ground. The foundation covered a space of four acres. The structure terminated in four legs, and was firmly connected with the sub-structure and the soil by long iron bolts. Thus there was no impediment to the free passage of the electric fluid, and all risk of damage to the structure itself was effectually removed. One singular circumstance remains to be recorded. Immediately the Tower was struck it was hidden from view by a thick haze. The density of this may be imagined when it is stated that the glow of the powerful electric light was completely obscured. At first I

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