Upon those portions of the North Coast, which were chiefly surveyed during the Mermaid's first voyage, at a period immediately subsequent to the season of the rains, I had very favourable opportunities of increasing my collections upon the Goulburn Islands, Ports Essington and Raffles, Croker's Island, Mount-Norris Bay, and on the shores of Van Diemen's Gulf; and among many described species, discovered formerly in the great Gulf of Carpentaria, there were several most interesting new plants. With a view towards an entire completion of the survey of the several coasts of the continent, that part of New South Wales within the tropic, north of Cape Bedford, which was not seen by Captain Cook, entered into the plans of the Mermaid's second voyage; and it was highly gratifying to my feelings to reflect that it was reserved for me to complete several specimens discovered formerly in imperfect states by those eminent naturalists who accompanied the above great circumnavigator, in 1770, desiderata, that have been wanting ever since this period of their discovery; no mediums of communication with those particular parts of the coast having presented themselves. The aggregate of the several collections that have been formed during the progress of the four voyages under the general circumstances above briefly referred to, and which, as constituting a small Herbarium, will be thus collectively spoken of in the following remarks, does not exceed one thousand three hundred species of Phaenogamous plants; of these five hundred and twenty are already described by authors, the other portion being in part unpublished species, previously discovered on other coasts of Terra Australis, and in part absolutely new, referable, however, mostly to well defined genera. Of Cryptogamous plants, there are but few species, and of these, or parasitical Orchideae, none have been detected in these voyages in addition to those already described: a circumstance, that with respect to the North-west Coast can reasonably be accounted for, from the non-existence of primary mountains, or land above very moderate elevation; by the absence of lofty dense forests (points of character necessary to that permanency of atmospheric moisture, which constitutes an essential requisite to the existence of almost the whole of these tribes): and the consequent general exposure to the sun of those arid shores.