In 1843 the New Carnivora Terrace was constructed. This formed part of the plan of Decimus Burton, but was not then adopted by the Council from a fear lest the animals should suffer from exposure.
The walk was extended for about 150 feet from the bear pit over the roof of the dens, of which there were originally six on each side. Each cage was 24 ft. long, capable of division into two or four compartments, with an inner sleeping den two yards square for every 12-ft. cage, properly ventilated, but at the same time carefully contrived to exclude cold and retain the natural heat. The only protection at first was an awning to shield the animals from the direct rays of the sun or from storms or rain in winter. In September the animals were removed to their new quarters; and, according to the Council's Report presented at the Anniversary Meeting in 1844, the effect of more air and greater exercise became visible almost immediately.
From the Guide published in 1844 it appears that the cost of the terrace extension and the new dens was £3,000. The tenants of the new quarters were: a young lion from the Cape; lionesses, one of which was deposited by the Queen; two tigers; pumas, which had bred; African and Asiatic leopards; a spotted hyena; striped hyenas (male and female); a Cape hunting dog; a Malayan sun-bear, a Polar bear, and a Syrian bear.
In 1848 a shed was built, with a paddock attached, just west of the giraffe house, for the European bison. The area was well drained, and an artificial raised surface constructed of brick-rubbish and gravel which gave no lodgment to water in unfavourable weather. The wants of the gardener were considered, and for his benefit a small stove house for propagating plants was erected.
The abandoned carnivora house in the North Garden was converted into a room for reptiles in 1849, and this was the first instance of a special building being devoted to animals of the order; the west wing of the giraffe house was built, and the east wing begun, though it was not finished till the following year. This last work was undertaken in anticipation of the arrival of the hippopotamus.
A new series, with coloured plates, was commenced in 1848; Joseph Wolf furnished many of the illustrations, and this was his first connection with the Society. A cheap edition, consisting only of the text, was also issued. In the first volume there were twenty-three plates, each illustrative of a new species.
(Partial text:) The Zoological Society of London. This Edition is limited to 1,000 copies, of which this is No.377. 1905. Henry Scherren, F.Z.S., Member of the British Ornithologists; Union.