Featured artists: Susan Ryman, Vicki Hamilton and Joanna O'Toole

There were, I think, fragments of ancient mosaics, suggestive pears and marauding insects, all of which still figure in the present exhibition at Art Systems Wickham until September 15, though accompanied by an encyclopaedic collection of diverse figurative objects. Drawing skills are never in doubt.

There are many fish and faces, eyes, snakes, feathers, pearls, glass domes, nests, moths, roses and sprays of foliage. There are even two pork chops; all emanating from an apparently inexhaustible visual imagination, declaring its surrealist subversive messages from the deep layers of the unconscious.

This time there is a greater number of larger works, often surrounded by smaller pieces. Two notable works feature the classical memento mori motive of a ram's skull. One is placed as a Victoriana centrepiece. The other includes a sloughed snake skin, as well as fragments of antique mosaic. This blend of past and present is also suggested by a presiding raven. That epic harbinger of doom provides the original impulse for this body of work and makes an appearance in a small but crucial work.

It is impressive that the artist can still achieve such old master effects with multiple coats of varnish over coloured pencils. It is a technique she has honed over many exhibitions.

Vicki Hamilton's splendidly displayed exhibition of dogs at the University Gallery until September 14 extends her previous porcelain animal sculpture into a PhD project.

We may well remember her small, unglazed white creatures, often deeply poignant. Among them were noble hounds damaged by scientific experiments and honey bears milked for their bile to supply an ingredient in oriental medicaments. Her current work features dogs of many breeds at the mercy of vicious or thoughtless, even if well-meaning, human beings. What has been a powerfully supportive relationship can become another form of commodity exploitation.

On display are puppies bred for sale, greyhounds no longer suitable for racing, an ageing fighting dog, circus entertainers and an adorable lap dog wrapped in pink brocade and no longer able to behave or express itself as an animal. A grouping of the evolving paws of many breeds shows how successive interbreeding to produce characteristics desired by humans is incompatible with canine health or happiness.

Skilful modelling in stoneware and earthenware, along with the delicacy of porcelain, invokes the qualities of skin as well as the flickering muscles beneath. We are made to feel for these dogs, captive to our unthinking desires. But of course dogs can still lead useful doggy lives, often as essential members of human families. Dogs, and surprisingly elephants, are the earliest of our fellow animals to choose to share our lives. It is no wonder that over the course of millennia we have learned to read their minds and emotions, and they ours.

We may even have taught them to echo our responses.

Joanna O'Toole is a painter and sculptor who has won many prizes for monumental constructions, balancing the contrasting presence of old iron with the power and vivid colour of raw timber. But for the current exhibition at Curve Gallery, which closes today, she is showing a whole new body of work in conjunction with her husband Warwick.

He has long been a maker of fine timber furniture and brings well-honed craftsmanship to this joint project of giant wooden pencils as tall as tree trunks yet realistic in every detail. They tower above the viewer, as imposing as the monumental hand tools of Swedish-American Claes Oldenburg, that hero of the pop movement from 40 years ago.

Apart from the vertical monoliths, the exhibition includes hexagonal cross sections in a flowerbed of colours, an eraser as big as a bench and a pencil spectacularly shattered.

We are invited to question the significance of this basic mark-making tool. Scale lends importance to something we take for granted. These baulks of Douglas fir make us think of the vast forests cut down to provide this familiar writing implement and perhaps to reflect on the commercial empires founded on it.

I still can't work out how you get the graphite in.