This search for plants was no mere hobby, to be taken up for a time and then dropped, but it developed into the serious business of life, ceasing only for about a year before his lamented death. In short, for some fifty years Petrie carried on this essential preliminary work, so that there is not one of the botanical districts of the main Islands of New Zealand where his footsteps cannot be traced; indeed, he was fairly familiar with the distribution of the flora from the north of Auckland to the south of Stewart Island; and the results of his many excursions—long or short—are stored, well preserved and accurately labelled, in his splendid herbarium—the supreme work of his life. Besides being a skilled collector, an accurate observer, and the patient maker of an herbarium, Petrie contributed some sixty papers to the Transactions of the New Zealand Institute and other journals. The greater part are descriptions of unknown plants—in all about 180 species or varieties. Two papers stand out as of special value—the one a list of all the species of spermophytes of Otago, and the other dealing with the flora of Stewart Island, which was almost unknown until he and G. M. Thomson made a special excursion thereto in a cutter they hired for the purpose. In the former of the above two papers a list is given of all the species, together with details regarding their distribution, in Otago. Within the last few years it has been my good fortune to follow in Petrie's footsteps, so to speak, in Central Otago, ascending many of those mountains whose florulas he made his own, yet not one plant have I found which he had not previously seen or recorded. This speaks volumes for his thoroughness. And those who, like myself, have been with him in the field in his prime must have been amazed at his eye for plants, an eye which missed none. During one long summer's day on Kelly's Hill, Westland, I well remember he looked neither to right nor left, but steadily gazed at the carpet of plants hour by hour, pausing only to collect those which were new to him or which he wished to examine; and this was my daily experience during a rather extensive excursion he and I made about thirty-one years ago. The Stewart Island investigation was confined to the areas—mostly low-lying—in the neighbourhood of Paterson Inlet and Port Pegasus, but from the head of the former beautiful lake-like arm of the sea the explorers managed to negotiate the swampy ground leading to Mason Bay. No less than 201 species were collected or noted, a remarkable record for a comparatively small area, the country difficult to traverse, and the time at their disposal severely limited. Various important facts were made known, especially the discovery of the Australian genera Liparophyllum and Actinotus, the occurrence of certain alpine plants at sea-level, and the virtual absence of grassland, this being represented by Cyperaceae and Restionaceae. Certainly, in this expedition G. M. Thomson played a notable part, and Petrie suitably emphasized this in Microlaena Thomson—a small grass of unusual form, now known to extend to north-west Nelson. Had Petrie been asked what was the main result or chief object of his botanical work, he would have unhesitatating replied that it was the putting-together of an herbarium which would represent all that was known taxonomically regarding the species of New Zealand vascular plants (for with their ecology or other matters he had no concern) and their distribution. To this end, his explorations, his correspondence, and, in fact, all his botanical energies, were devoted. And so far as his conception of an herbarium went—and unfortunately it is the usual conception—he succeeded to the full. Not only is his own painstaking work of some fifty years represented, but he enlisted the assistance of pretty well every one who