So far as Great Britain is concerned, and it may be taken as a criterion of Europe generally, the most comprehensive record of sources and dates of the introduction of South American plants is Loudon’s _Hortus Britannicus_, first published in 1830. It enumerates something like thirty thousand species, exotic and otherwise. As the importation of South American plants was only in its infancy at that time many hundreds of flowers, now familiar in gardens and hothouses, are not recorded, but the book is reasonably complete up to the time of publication. Most of the more important introduced aliens, before and after the date of Loudon’s great work, may be found described and illustrated in the _Botanical Magazine of London_ (issued monthly from 1787 to the present time), while others are dealt with in Loddiges’ _Botanical Cabinet_, 1818–24, and in many other of the quantity of horticultural publications appearing in Europe during the first half of the nineteenth century— notably in Nicholson’s _Dictionary of Gardening_ and in the revised edition of Johnson’s _Gardener’s Dictionary_, bringing the record to the end of the nineteenth century. Whilst many European botanists, such as Langsdorff, Burchell, Lhotsky and others had, during the earlier decades of the nineteenth century, explored certain parts of Brazil, nothing was of more importance to general knowledge of the plant-treasures of the country than the work accomplished by a Scotch botanist, Dr. George Gardner, afterwards Superintendent of the Botanical Gardens of Ceylon. His _Travels in the Interior of Brazil_ during 1836–41 is a record of high merit, not only on account of its contribution to Brazilian botany and natural history, but because it is a faithful and genial picture of life and conditions in the interior of Brazil three-quarters of a century ago. The amazing richness and beauty of Brazilian flora had never before been revealed to Europeans as through Gardner’s book and his collections of thousands of specimens; it is extraordinary that these fascinating _Travels_ should have remained out of print.