Kitaj's bitter farewell to the UK, in this year's RA Summer Exhibition, is just one part of a wide and colourful showcase

The Royal Academy's Summer Exhibition always causes a degree of fuss and critical fluster and this year's show, which opened to the public on Sunday, is no exception. Most of the attention thus far has been aimed at RB Kitaj's contribution Sandra Three, or at least at his theme (one man's continuing war against the critics) and at its deliberately provocative pounds 1m price tag, although, oddly, there has been very little written or said about the work itself.

It is a rather perplexing picture, or series of pictures, cuttings and photocopied pages spread along one wall of Gallery II. An assemblage, if you like, based around Kitaj's obsession that the critics killed his wife. It consists of three Kitaj originals: the centre section depicting the artist himself as a soldier from Manet's Execution of Maximilian, his rifle aimed at a bile-spewing critical monster which he suggested, in these pages last week, owes most to The Independent's Andrew Graham- Dixon. This is flanked by a portrait of Kitaj's son Max playing the violin; and a small panel titled My Second Abstract, Nietzsche's Moustache, a Hodgkinesque little painting in brown and orange.

Manet looms large in Kitaj's imagination: also included along the wall are a lithograph of his famous Execution picture, an etched portrait of him by Degas and a page with his words: "The attacks against me broke in me the mainspring of my life." This, says Kitaj, is the note on which he leaves this country after 30 years. It is a sad end to a distinguished career in Britain and one can only hope that the Californian sunshine will cheer him up.

Kitaj has also chosen the other pictures in Gallery II, by way of a more fond farewell or, as he puts it, "I have invited a few of the over-the- hill-gang to join me in a room because I believe in a geriatric avant- garde." It's a nice idea and good to see the likes of Freud and Auerbach on the Academy's walls, but it's a disappointing selection. Freud's drawing of Francis Bacon, for example, looking weirdly sexy with fly unbuttoned, is an intriguing document of the 1950s, but it's far from being Freud at his best, nor are Auerbach's painting of Sandra, or Hockney's Vittel Bottle really representative of their respective abilities.

This year's memorial display is to another artist who might have had cause to feel aggrieved at the nation's critics, although I doubt that any such feelings were in his nature. William Gear, who died earlier this year shortly after his 80th birthday, has always been more admired in Holland and Belgium than at home. There, he has a reputation and a following, here he has a wall of six paintings amid 1,200. These memorial displays always seem like rather slight tributes, but at least Gear's is a good selection, including his Academy Diploma work The Black Tree, from his fuzzy soft focus phase in the late 1950s, and the cool tonalities of pale blues, greys and browns at work in the more organised Structure Sept 1956.

Some of the Academy's surviving octogenarians also fare well in this year's exhibition, especially Leonard Rosoman, whose sprightly watercolours of Roxanne Swimming are as good as anything that he has done for years, and Morris Kestelman, whose subtle abstractions just manage to hold their own on a wall with John Hoyland's shocking pinks and acid greens and Adrian Berg's technicolour vegetations.

As ever, the Academy stalwarts are reliably recognisable: John Bellany, Mary Fedden, Albert Irvine and Craigie Aitchison all stand out from the crowded walls and Tom Phillips is in particularly inventive mode with needle and thread and prostitutes' calling cards. Whatever one makes of these artists' talents, and none of them should be judged by individual pictures or by the visual chaos into which they annually combine, the Summer Exhibition is a great English institution. It has its faults, but it also has its strengths, not least that it provides for hundreds of people to spend money on art without suffering what they perceive (wrongly) to be the intimidations of the dealer system.

I visited on the first day of the Friends' preview and an early favourite with the ladies in tweed was a tiny etching by the Academy's past president, Sir Hugh Casson - a flurried depiction of a man on a bicycle which had already gone 27 times at pounds 90 from an edition of 90. Still available, not surprisingly, but all bargains to my mind, were two untitled etchings by Heather Penney at pounds 295 each, Danny Markey's delightfully wonky Still Life at pounds 900 and Philip Reeves' sombre, but very satisfying Rural Interior at pounds 3,000. These are subtle pictures, too subtle perhaps to find buyers in such a hectic environment, but they are worth trying to find in the throng.

Royal Academy of Arts Summer Exhibition, London W1 (0171-439 7438). To 10 Aug