The galleries: Veterans with lots to say

Two veteran artists, in a sense our Old Masters, who still continue to change and grow, have exhibitions this week, a rare event.

At the Milford Galleries until April 8, Ross Ritchie's Trompe l'Oeuvre has one of his deeply thoughtful shows that reflect the local scene but also have much else to say. In the best post-modern fashion, his paintings reference many things but they also have impressive size, and qualities that make them rich images and profound meditations on the nature of paint and illusion.

At the simplest level this is apparent in a work called Skin, made up of 48 pieces. They are lessons on how to paint an onion. Half the panels have a dark background, half a light background. The whole is a remarkable tour de force of variations on a theme.

River Landscape is basically a magnificently painted river, plain and hills, but in the corners there is a hint of a grid. This has nothing to do with the structure of the hills but everything to do with the structure of the painting.

Two smaller canvases stand proud of the surface - they are not just details of the main painting but provide contrast and alternatives.

Then there are the tricks of perspective: the table in the foreground, the box, a shelf with all the paraphernalia of the studio. This is a painting about the decisions of painting as well as the instruments of the craft.

The nature of the process is revealed in The Studio, elsewhere called "the factory". Not only does the world go by across a viaduct with its implications of solid construction, but there is a tiled wall which is a beautiful surface that would make the name of a painter who concentrated only on surface. But there is more to painting than surface and a tiled panel that leans against the tiled wall shows this. How do we know it leans? Because it throws a shadow. It is a neat demonstration of the nature of representation. There is also a deftly painted still-life.

In the grandest of the works, Stoop, the image speaks of solutions for strength that have been found by other painters. The top of the canvas has the weight of McCahon, the symbols of the stooping figures are taken from rural labour by Millet, and it is given solemnity and strength by head-dresses which recall Piero della Francesca.

The solemnity of these works is emphasised by the prevailing grey tones and could make them seem dry if it were not for the variety of visual effects drawn from life and thought that make them extraordinarily stimulating.

Where Ross Ritchie does works of majestic size, Michael Shepherd (at 40 George St, Eden Tce in an exhibition that runs until April 15) is a miniaturist. Miniature might suggest something historical but these works are up-to-the-minute in their shape, framing and context. They also have a complex depth of historical reference.

Each painting shows a plant. There is nothing spectacular, just roadside plants - but these plants are painted with an extraordinary concern for the foliage. They are mostly bushes and the cloud of their foliage is conveyed by a mass of tiny touches in sepia. The earth is indicated by quick dashes of paint, except for the specimen in a plastic pot. The impact is muted but the precision fascinating.

As botanical drawings these would be splendid, but the ironic complexity comes in the way it is suggested that the nature and form of these plants is connected with the extinct moa. These plants are representative of the New Zealand plants that have a juvenile form which seems to change at about 3.3m, that is, the size of a large moa.

When New Zealand was much drier many plants defended themselves against the moa by shrinking, part of a process called divarication, which gives its name to the exhibition.

A further spin is added by a reference to Cockayne, a mythical land where everything was plentiful. Coincidentally, Dr Leonard Cockayne was one of our earliest conservationists. This is a quiet, lovely, profoundly thoughtful exhibition.