DOWN IN the meadows by the stream there is a fair scattering of what I take to be shaggy ink-caps - elegant, tall, slender mushrooms which come up beautifully white but in a day or two turn black in the gills, and then sink down to become puddles of slimy liquid dark as pitch.

I say 'what I take to be', because there is a chance that these are not shaggy, but common ink-caps - and between the two there is a savage difference. Whereas the shaggy kind are harmless, the common variety produce a violent reaction if eaten in conjunction with alcohol: palpitations, hot flushes and nausea (they apparently contain a chemical akin to that used in alcohol-aversion therapy).

Tempting though the ink- caps look, I am therefore leaving them alone - and to forego what could be a memorable gastronomic experience is disappointing in an autumn that has all the signs of being a poor wild-mushroom season. Last month in Scotland we searched in vain for chanterelles, in birch and pine woods whose moist, mossy banks should by then have been carpeted with little butter-yellow trumpet shapes. Finding only one or two, we concluded that the weather had been too dry. That part of Inverness-shire is usually the wettest area in Britain, with (in one glen) an annual rainfall of 220ins a year. Yet during the month preceding our visit not a drop had fallen.

That is almost always the way with mushrooms: it is too hot, too cold, too dry, too wet. Down here in the South, by contrast, we have had deluges of rain, but even those great thugs among fungi, giant puffballs, seem to have failed. Normally, by now, I can see several simply by looking out of the windows: they come up in favourite sites on the hillsides and sit there like shining white beacons, visible from a range of half a mile.

Why are there none this year? The answer seems to be that conditions were never quite right. What fungi like is very hot weather in summer, which enables their mycelium, or root-system, to develop fully, followed by a sharp drop in temperature and heavy rain. We have had the rain, but we missed the heat, the only consistent spell of good weather, in May and June, having come too early to do the trick.

In times of scarcity, one should take advantage of every edible fungus which does grow - and here I curse my ignorance. The excrescence in the spinney looks like wood blewit, described by Antonio Carluccio, the fungivore, as 'the most exquisite edible wild mushroom in Britain'; but could it not also be a woolly milk-cap or a bitter boletus, both of which he strongly recommends one to leave alone, as they are poisonous?

Regarding the blewit/milk- cap/boletus with suspicion as I set out on a walk the other afternoon, I went up through the woods with my mind focused on an upland meadow which is generally the best bet for ordinary field mushrooms. There they grow mainly along either side of, and sometimes on, a path trodden bare by sheep and cattle; and as I climbed I wondered why they persistently appear in some places but not others, when, to a human eye, a whole field appears equally favourable.

The permanent pasture in our valley is never ploughed up. Many fields, ours among them, are never contaminated by chemical sprays or fertilisers - yet very few of them produce mushrooms. Does animal manure promote the growth of fungi? And is there any truth in the ancient belief that stallion droppings are particularly beneficial?

Reaching the edge of my target field, I was glad to see that the cattle which grazed there earlier had been taken away: at least, if there were any mushrooms, they would not have been trampled. I need not have worried. A couple of long passes, out and back, revealed no trace, and I turned for home disappointed yet again.

My route took me along some steep grass banks at the top of the escarpment. In summer the owner had not bothered to cut the thistles, and now, having done their deadly work of scattering down to the four winds, their skeletons stood brown and shrivelled, giving the fields a rough and ragged look.

Suddenly, through the dry stems ahead, I saw something white. I advanced on it incredulously. It could not be . . . it was: an immense horse mushroom - a larger cousin of the ordinary field mushroom - fully 10ins wide. The sight of it sent my mind flying back to Old Bill, a gamekeeper friend of yesteryear, in another county, who at this time of autumn, would make regular pilgrimages to a field in which phenomenal horse-mushrooms used to grow. 'Big as dinner-plates,' he would announce triumphantly, after his first successful reconnaissance. 'Need a bloody wheelbarrer to fetch 'em out.'

Well, this fellow was on its own, but it was fully the size of a dinner-plate. Alas: closer inspection revealed that slugs had found it first. When I turned it over, I discovered that half a dozen of them had eaten their way into the pink gills, among which they lay snugly embedded.

In theory it would have been possible to cut out contaminated areas and salvage some part of this monarch of the meadow; but I decided to leave it to the slugs, and was preparing to come away when another patch of white caught my eye. Once again incredulity struggled with the visible evidence: there, a hundred yards away, was not one horse mushroom but a whole patch of them.

None had grown to the proportions of the first monster - but equally, none was old enough to have been invaded by slugs. The largest had opened out and was about five inches across; the rest were still closed, ranging in size from squash to cricket balls, and mercifully free of maggots, which, given half a chance, eat their way up the stalks and invade the crowns.

Any mushroom hunter with the slightest sense equips himself with a couple of plastic bags in his pocket; yet so demoralised was I by fruitless earlier expeditions that I had come without any container. The only remedy was to take off my sweater, tie one wrist in a knot, and use the sleeve as a bag.

Even though I left the smallest buttons, in the hope that they would grow on, my makeshift carrier was soon full - and an awkward burden it made: a long, fat sausage that dangled nearly to the ground, and had to be carefully nursed over fences on the two-mile journey home.

In the kitchen, the mushrooms filled a large bowl. I did not bother to put them on the scales, but they must have weighed at least 3lbs.

Do not tell me that, for a modest expenditure and a very great deal less effort, I could have bought the equivalent in a supermarket. For one thing, no cultivated fungi could have matched the taste of mine, which went into the oven with some dry-cured bacon and came out divine; and for another, no shopping expedition could ever appease the instinct of the hunter-gatherer, whose delight it is to bring home the wild fruits of the season from the remotest corners of the hills.

Antonio Carluccio's 'A Passion for Mushrooms' is published by Pavilion (pounds 9.99).