6 volumes bound into three books: I-II, III-IV, V-VI. Half-leather bindings with marbled boards. Leather a little dry and worn, and gilt title of second volume is quite rubbed. Couple of spots to the upper page edges, and corners are rubbed, and volume 3 has some loss to the upper corner of the front endpaper. Endpapers, page edges, contents pages and some of the early/late pages in each volume are quite heavily foxed, but most pages (after the first 15-20) are on the whole very clean and bright for their age with the occasional small spot and only very light yellowing throughout - there is the occasional patch of heavier foxing, but at an estimate, more than 90% of all the pages are clean and good. Absolutely packed with fabulous in-text illustrations of animals which are extraordinarily detailed: you can see every hair, feather and scale, even of a tiny snake in the grass...it is really wonderful to study. Also quite a few full-page plates. Very comprehensive text also, but it is the marvellous illustrations which really bring this book to vivid life.