In 1913, when his work had become of Dominion importance, he removed to Newtown, Wellington, afterwards residing in the pretty little hill suburb of Ngaio, where he lived till the time of his death. His later years were shadowed by almost total blindness. He died on July 8, 1934.

Honours were showered upon him during his career, and particularly towards the end, to an extent unprecedented for a New Zealand scientific worker. A few of these may be mentioned here. In 1903 he was made a Ph.D. of Munich, in 1910 he became an F.L.S., in 1912 an F.R.S., and in 1930 a C.M.G., a rare distinction for a scientist. In 1928 he received the Darwin medal of the Royal Society, the most precious prize a biologist can win, and in the same year the Mueller Memorial Medal. Naturally, he also won all the available local distinctions, e.g., in 1912 the first Hector Medal, in 1914 the Hutton Medal. He was an original Fellow of the Royal Society of New Zealand, and was President of it in 1918–19, a corresponding member of many foreign societies, and had various doctorates bestowed upon him.

These honours he appreciated highly, but his abiding love was for the flowers of the garden and of the wild. Wherever he went, he cultivated them, both introduced and native, in endless procession. Thus it was fit that he should be laid to rest amongst them. His grave is in the Otari Open Air Museum, a botanical reserve for native plants, not far from his old home at Ngaio. This garden was a pet project of his own, and to him are due its inception, arrangement, and many of its actual plants. Thus he had built a memorial for himself there.

Now let us turn to his achievements in the botanical field. When he commenced his work, the older botanists of the ‘nineties of last century, in spite of theories of evolution, had a strong belief in the general fixity of plant species, partly due to the fact that they relied largely upon dried herbarium specimens in drawing up their descriptions. Cockayne, as we have seen, however, was in the first place a horticulturist, and in the garden found that plants responded by change of form to change of environment. He was secondly a field botanist, who went to the wilds not merely to collect specimens for his herbarium, as others did, but to observe closely the living changing organism in its natural and varied habitats.

As a gardener he collected seeds for cultivation; but up to this time the orthodox botanists had paid little or no attention to seedling or juvenile forms. It was the mature flowering or seeding form on which they concentrated their attention. Certainly in a few cases (e.g., Pseudopanax, Sophora, etc.) they had been compelled to distinguish the juvenile forms; but Cockayne early came to the conclusion that a large number of our species exhibited strikingly different leaf and growth forms at different stages of the plant's development. Indeed, he definitely states that in “no flora in the world is this phenomenon of such a common occurrence as in the flora of New Zealand.” (Trans. N.Z. Inst., 1899, vol. 31, p. 356.) Further stimulated by Lubbock's work, he commenced his study of

seedling forms, and showed that they were of immense importance for tracing the plants' ancestry (l.c., pp. 354–398); but the subject that fascinated him more than any other was the response of the plant to changed environment. The thoughtful old botanist and shoemaker R. Brown, had pointed out to him how in a moist, warm environment the whipcord Veronicas (Hebes) developed true leaves in place of leaf scales; and from that time on Cockayne was launched on the fertile study of the relationship of plant-form to habitat, a study he maintained and developed until the last.

His first paper was “On the Freezing of N.Z. Alpine Plants,” and as it was not followed up, need not concern us here. His second was on “Seedling Forms,” and his third on the “Burning and Reproduction of Subalpine Scrub and its Associated Plants” (Trans. N.Z. Inst., 1899, vol. 31, p. 398), his fourth “A Sketch of the Plant Geography of the Waimakariri River Basin, Considered Chiefly from an Oecological Point of View” (Trans. N.Z. Inst., 1900, vol. 32, p. 95).

Thus, by the end of the century he had introduced to New Zealand botanists at least three new branches of botany up to that time almost unknown to them:—

• (1) The changing forms of the plant from the seedling onwards. This work was continuously followed up by Cockayne, and is being pursued by other New Zealand botanists (Hetero-blasty in the sense of Goebel).

• (2) Plant Succession, by his paper on the reproduction of scrub in the neighbourhood of Arthur's Pass. The investigation of that district, thus initiated, is still going on. In the Journal of Ecology, August, 1932, appeared a paper by L. Cockayne and J. W. Calder “On the Present Vegetation of Arthur's Pass as Compared with that of Thirty-four Years Ago.”

• (3) The response of the species to environment-epharmony. His fourth paper on the Plant Geography of the Waimakariri basin contained numerous references to this subject. This is still one of the richest fields of exploration for the New Zealand botanist. All Cockayne's work was abundantly fertile, but these new fields of work were looked upon somewhat askance by the more conservative botanists of the day. Cheeseman, however, to his credit, later gave Cockayne a due meed of praise.

Actually all these studies threw a new and unexpected light on taxonomy, and in many cases altered our conceptions as to the limits of a given species. Cockayne himself described many new species that he had found in his wanderings over the length and breadth of New Zealand, and his descriptions were such that few of them have been challenged, though later his own views on hybridism led him to abandon some of them.

On these lines his work extended, and in 1912 he summed up his theories in a paper still significant for New Zealand workers, “Ecological Studies in Evolution” (Trans N.Z. Inst., 1912, vol. 44,

pp. 1–50). It should, however, be remembered in reading this that Cockayne's conceptions were continually altering and developing, and that some of the generalisations in that paper were afterwards changed by him or modified in expression. Here, for example, he discusses the meaning of the term “variation.” Later the word itself became to him “anathema,” and if a fellow-botanist used it, he was deluged with a torrent of invectives. But in this paper he was chiefly concerned with the relationship of epharmonic adaptations to the theory of evolution. By his classic experiment on Discaria toumatou (The New Phytologist, 1905, vol. 4, No. 4, p. 79) he had shown how a rigid spiny leafless xerophyte by cultivation in a moist greenhouse could be converted into a more or less meso-phytic plant without spines, but bearing leaves on long pliant branches. In doing this it returns to its juvenile form. The problem was, and still is, how far the various forms are selective and hereditary. Cockayne, dealing with such and similar cases, stated “that in the hereditary epharmonic variations cited below there is much greater likelihood of their having been brought about by the directive action of various ecological factors than by the continuous accumulative selection of fluctuating varieties”; that is to say, he denies the method of selection as enunciated by Darwin. In order to do this, he brings a wide range of evidence to show the effects of wind, moist culture, altitude, dry climate, and so forth on the vegetative characteristics of the plant, and argues that the trend of the evidence is to show that those effects are heritable.

He had, however, already become acquainted with the mutation theories of de Vries, and was, further, even beginning to suspect that hybridisation was an important factor in producing some unexplained forms, e.g., “In short, hybridisation may account for some of the variation in Celmisia” (l.c., 1912, p. 31), and it is to his study of wild hybrids in his later years that much of his European fame is due. At this time he could say, “Hardly anything is known as to the occurrence of wild hybrids in New Zealand” (l.c., 1912, p. 30). Now there is probably no country in the world where they have been so fully studied, and that owing to the work of Dr Cockayne and his pupils. In 1923 he wrote an article in the New Phytologist (vol. 22, No. 3, p. 105) “On Hybridism in the N.Z. Flora” in support of Lotsy's “Evolution by the Means of Hybridisation.” Henceforth he abandoned the term “variable” and replaced it by “polymorphic,” and employed the terms “micro-species” and “biotype” for what he was later, following Lotsy, to call a “jordanon.”

All this discussion of the significance of the term “species” and the effects of environment led to intensive work in taxonomy of a much more critical character than had before been attempted by New Zealand botanists. The climax of his work in systematic botany may well be represented by his paper with Dr H. H. Allan “On the Present Taxonomic Status of the N.Z. Species of Hebe” (Trans. N.Z. Inst., 1927, vol. 57, pp. 11–47). In this he adopts the terms “jordanon” and “linneon” of Lotsy and accepts the fact that hybrids between closely related species occurring together are

likely to be abundant. This paper sets a standard for subsequent workers in New Zealand taxonomic botany that few of them are likely to attain.

In 1927 there appeared in the Journal of Ecology (vol. xv, No. 2, p. 234) a paper entitled “The Bearing of Ecological Studies. in New Zealand on Botanical Taxonomic Conceptions and Procedure,” by L. Cockayne and H. H. Allan. This paper is of fundamental importance for all students of the taxonomy of New Zealand phanerogams. In it Cockayne and Allan explain fully and cautiously the terms they use, and illustrate them by numerous examples. The isolation of New Zealand, the high percentage of endemism here, its virgin vegetation and varied climate make New Zealand unique for the study of the problems at issue. This analysis is also of the highest importance for students elsewhere. It is clearly shown here that species of the earlier botanists were of a very heterogeneous character, and too often based not only on insufficient material, but lacked the backing of sufficient field and experimental observations. Polymorphy is fully considered and defined, heteroblasty in the sense of Goebel is discussed, the term “epharmony” is explained, and the best methods of work in the field expounded, all with a great wealth of illustration. Finally the word “epharmone” is coined. “Hybrid swarms” are described and their significance discussed, and the hope is expressed “that new workers,” free from the thraldom of the dangerous herbarium artificial method, would come forth.” Probably no paper of greater significance for the definition of species of flowering plants has anywhere appeared in recent years.

Meantime, Cockayne, in addition to his purely scientific work, had prepared many valuable reports of economic value for government departments and other bodies. For the Department of Lands he made a botanic survey of Kapiti Island in 1907. Later surveys were made of the Waipoua kauri forest, the vegetation of Stewart Island, and the dune areas of New Zealand. The last-mentioned was a particularly fine piece of work. For the Flaxmillers' Association a report was prepared on the flax disease. For the Forestry Department he prepared a monograph on the N.Z. beech forests, and entered into extensive investigations of the montane tussock grasslands of Central Otago. Only a few of these reports are here mentioned.

An intensive search for wild hybrids was now in full swing. The discovery of hybrids in the beech forests increased his interest in the problems raised. This work culminated with the publication in the Annals of Botany (1934, vol. 48, pp. 1–55) of an “Annotated List of Groups of Wild Hybrids in the N.Z. Flora,” by L. Cockayne and H. H. Allan, in which no less than 491 hybrid groups are enumerated.

It is impossible here, however, to do justice to the extent and variety of his work. In the course of it he travelled from one end of New Zealand to the other and visited most of the outlying islands, thus accomplishing many difficult and arduous journeys; but always he had in mind his one central aim, the elucidation of some of the problems of plant evolution as exemplified in the New Zealand flora.

Such solutions, if accomplished, would of course not only be true for New Zealand, but mutatis mutandis for the rest of the world.

Now as early as 1904 he was asked to write the volume on New Zealand in that encyclopaedic production Die Vegetation der Erde. The war intervened, and the first edition was not published till 1921. A second edition was called for, and appeared in 1928. This monumental volume he always regarded as the crown of his life's work. It is a comprehensive survey of the history of botanical research in New Zealand, with an elaborate account of the vegetation of Primitive and Semi-primitive New Zealand from the sea coast to the mountain tops, from the Kermadecs to the Bounties. Growth-forms are classified and plant formations and associations discussed with a vast and unequalled knowledge. The effect of settlement on the vegetation is described, the varying botanical provinces defined, and the origins of the different elements in flora investigated. It is a masterly and immense piece of work. One would not have been surprised to learn that a dozen men had collaborated to produce it; yet it is the work of one. It is a work of reference rather than a volume to be read and digested, one which must be constantly consulted in future by any student of the plant geography of New Zealand or by anyone who wishes to learn what is known of the life histories and habitats of individual species.

One may now sum up some of the chief contributions of Cockayne to botanical science in New Zealand. He showed, in some cases contrary to the beliefs of the old systematists:—

• (1) That plants were extremely plastic in their vegetative character in response to varied environments;

• (2) That even the individual plant frequently passed through many stages before reaching maturity;

• (3) That seedling and juvenile forms often bore witness to the conditions of the past;

• (4) That there was a tendency for plants growing in similar situations to adapt themselves to them by similar methods;

• (5) That the species of the older botanists were often more or less polymorphic aggregates;

• (6) That evolution in some cases arose from mutations and was not the product of the selection of repeated fluctuations;

• (7) That in New Zealand at least wild hybrids were abundant, their seeds in most cases viable, and that therefore these hybrids constituted an important factor in evolution.

It was in the plant as a living, changing organism, responsive to its environments and affecting it in turn that he was interested. not as a dead specimen in a herbarium. Its deeper characters were determined by heredity, but some of its external characters were the outcome of its circumstances. “Speaking of theories of evolution generally,” he says, “there seems good reason to consider that such, if not premature, are chiefly of value as a stimulus to biological research,” and in this doubtless he was correct. When, however, the

writer once suggested to him that there might be a hidden psychic factor in evolution, he scouted the idea, so he is not to be classed with such modern theorists as Driesch and Bergson. He belongs rather to another school.

Yet he regarded the organism as a whole, and not as a machine made up of separate parts. He was not a microscopist, and so far as I know took little interest in the minute microscope investigations of recent geneticists. “Our ignorance as to the minute structure, chemistry, and physiology of the protoplasm is profound,” he wrote in 1912, and probably would have re-echoed these words up to the day of his death. Neither was he a draughtsman, but he illustrated his writings by a splendid series of photographs, most of them the product of his own camera. Though he was one of the keenest of observers, it was as an experimentalist that he would particularly wish to be remembered. “The study of epharmony in its manifold phases is urgently required. Its vigorous prosecution should yield a rich harvest of observations to be examined in the light of experimental evolution.” These words sum up his methods.

A few words must now be said on Cockayne the man, and some attempt be made to show wherein lay his greatness. His was an open, challenging, enthusiastic spirit, consumed almost entirely by the desire to advance New Zealand's botanical knowledge. One of his most obvious characteristics was his refusal to accept the statements of previous workers in his own field without critical investigation. When he could disprove the generalisation of a predecessor he was delighted. Combined with this sceptical attitude was a remarkable fertility of imagination. One rarely met him without finding that he had some new ideas to unfold. Some of these were perhaps fantastic, and had to be cast aside on fuller investigation; but many of them led to fresh and fruitful fields of work.

He was early in touch with many of the greater foreign botanists, and frequently expressed his indebtedness to them. To Goebel, Diels, and de Vries he was especially grateful, and when Goebel, Lotsy, du Rietz, and Sir Arthur Hill came to New Zealand, their visits were a tremendous joy and stimulus to him. Naturally, he himself had pupils, who recognised him as their master, and a small school of younger botanists grew up in New Zealand, who followed his methods and adopted his outlook. One hopes that they will advance still further the methods of their master. Cockayne, though he did not suffer fools gladly, was a most generous and helpful friend. He despised somewhat the laboratory botanist, but was ready to help any worker, however humble, who was interested in experimental observational work. He himself was singularly happy, in that for some forty years he was able to pursue the work he loved without hindrance of any sort.

In speech he was fluent, forceful, and at times violent; but even when suffering under his denunciations, one knew that beneath there was a kindly heart. Yet those who did not know him well were apt to be disturbed by his vigorous invective.