For both readers and critics, the nature of MacNeice's poetic work as a whole is a matter of importance, and the second posthumous ''Collected Poems'', entirely re-edited by Peter McDonald, attempts, for the first time, to print MacNeice's poetry in groupings corresponding closely to the collections published by Faber between 1935 and 1963. This makes it easier to read the poet in the published forms in which he was read by his contemporaries. In choosing to re-create the environments of MacNeice's individual volumes of poetry, moreover, this new ''Collected Poems'' reflects the opinion that MacNeice works best in and through those separate volumes, particularly so in the brilliant return to form - and unique kinds of return on lyric form itself - of the last three collections. The texts of the poems in the new edition are based on a comparison of all printed versions, as revised in the light of the poet's later thoughts. This has resulted in a large number of changes. It is hoped that the present edition presents MacNeice's poetry more accurately, as well as more fully, than all previous collections.The new ''Collected Poems'' also includes, as appendices, ''The Last Ditch'' - the short book of poems which MacNeice published with the Cuala Press in 1940 - and ''The Revenant'', a cycle of songs written for MacNeice's wife, the singer Hedli Anderson, a selection of uncollected early poems, and from ''Blind Fireworks'', MacNeice's first published book of verse.