That it's Henry Moore should hardly be surprising

One might expect the elephant to be of interest to a sculptor: its mass and bulk, the wrinkled skin over the primeval frame, the roundedness of its form. That the sculptor in this case is Henry Moore should hardly be surprising.

His ''Elephant'' and ''Zebra'' are not, however, sculptures, or sketches for sculpture, but self-sufficient etchings. They are two from a series of zoo animals he observed and etched in 1981-82. Although prints, their character is essentially that of drawings - and, in a special way, of sculptor's drawings.

In 1953, Moore wrote: ''There is a general idea that sculptor's drawings should be diagrammatic studies, without any sense of a background behind the object or any atmosphere around it. ... And yet the sculptor is as much concerned with space as the painter. He must make the object he draws capable of having a far side to it, that is, make it an object in space. ... It is necessary to give it the possibility of an existence beyond the surface of the paper.''

These etchings of animals have just this quality of ''object in space,'' as do a number of strong drawings and prints he has made in recent years with such subjects as sheep, tree trunks and roots, and his own hands. They are realized with an uncompromising, three-dimensional factuality. Except for the suggestion of a wall in front of the elephant, which helps to locate the creature and to build its scale, these animals seem to boldly establish their own space in the ''air'' of the flat white sheet of paper.

''In sculpture,'' this English artist once said, comparing the solid ''reality'' of his chosen means of expression with the frequent spatial ambiguities of painting or drawing, ''the form actually does whatever you have intended it to do. And so you can be satisfied that you have made what you intended to make.''

Drawn with a spiky, sharp line and not a fluid or texturally suggestive one, Moore's ''Elephant'' and ''Zebra'' might be carved in wood or stone. They are definite, substantial. Their forms are like a charted landscape that hints its understructure by the configuration of its surfaces. The almost scratchy workings of his etching needle define the elephant's rounded body as if it were chiseled out of a block, or modeled. You forget that he started with a blank two-dimensional sheet of paper.

The zebra seems to walk out of its sheet: It has the immediate presence and palpability of - the donkey in the field that thrusts its muzzle suddenly toward you asking for sugar lumps. Using the gift of the animal's camouflage for ends quite contrary to its natural purpose, Moore exploits the zebra's stripes to make it super-visible, to define and describe its contours unmistakably, to feel the construction and boniness of its head, to circle the plump curve of its belly.

Moore has loved drawing from childhood. He has practiced it throughout a long and productive career as a sculptor. It has been by turns a means of spontaneous observation; of preparation for specific sculptures; of lifting fresh ideas from his memory bank; a means of, simply, enjoyment.

In his animal etchings he has made his drawings subserve intentions as nearly sculptural as drawing could be made to do. In these, he has drawn, with vivid solidity, very much what he ''intended'' to draw.