The latter years of his life fell within that stimulating period which followed the publication of Darwin's Origin of Species. But in the battle of giants which ensued he took no part. His attitude, indeed, was rather that of an amused spectator; and in the letters which are available, his references to the great controversy of the day, and allied topics, are mostly in a playful vein. "I do not know how cats purr," he writes to his friend Mrs Gatty, "and am glad you asked.... Have you never felt a something stop your own windpipe when pleased or grieved, when suddenly affected either way? 'Tis the first gurgle of a purr; you were a cat once, away in the ages, and this is a part of the remains." Almost his only contribution to the literature of natural selection was a "serio-comic squib," which was read before the Dublin University Zoological and Botanical Association on 17 February, 1860 and subsequently printed for private circulation, entitled "A Guess as to the Probable Origin of the Human Animal considered by the light of Mr Darwin's Theory of Natural Selection, and in opposition to Lamarck's notion of a Monkey Parentage." Darwin thought this production a little unworthy of the author. "I am not sorry for a natural opportunity of writing to Harvey," he says, "just to show that I was not piqued at his turning me and my book into ridicule, not that I think it was a proceeding that I deserved, or worthy of him[115]."
Similarly, Harvey rejoices over Charles Kingsley's Water Babies, and especially over the sly fun which is poked at Darwinism, and also at certain types of men of science.
Only once did he enter the lists with a serious criticism, when, in the Gardeners' Chronicle[116], he cites the case of a monstrous Begonia in objection to Darwin's views. Harvey, indeed, did not like the new theory. "I am fully disposed to admit natural selection as a vera causa of much change," he writes, "but not as the vera causa of species." Further than this he could not go, though much impressed with the arguments drawn from geographical distribution. "I heartily wish we were nearer in accord," writes Darwin at the end of a long letter to Harvey, "but we must remain content to be as wide asunder as the poles, but without, thank God, any malice or other ill-feeling[117]."
Thus it will be seen that Harvey took but little part in influencing the thought of his time; the materials for his work were gathered not from his own creative brain, nor from the thoughts of other men, but direct from Nature's storehouses; his study was the far-stretching shore, his companions
"The toiling surges,
Laden with sea-weed from the rocks,"
his duty the describing with pen and pencil the harvest of the sea. In his works, he rises above mere technical description of the species with which he is dealing. His mind is filled with the beauty and wonder of plants; and he strives to impress the reader with the deep interest of the study of botany. He endeavours always to popularize his favourite pursuit by means of pleasant general introductions, and to promote a better knowledge of seaweeds or of flowering plants by appealing to his readers to collect, and by giving instructions for the gathering and preserving of specimens.
He derived a peculiar satisfaction from the thought that, at his post at Trinity College, Dublin, he was building up a great permanent collection that would be useful to future generations of botanists. "Here," he writes, "I sit like a turnspit roasting the meat, and when I am gone I suppose another dog will be put in my place. The Herbarium will not be broken up. I am content, for I seem to be working for some little purpose. I should just like to leave it in better order—to get through the arrears—and to return borrowed specimens." It was the same thought that prompted him to the publication of the great descriptive works which his rapidity and skill with pen and pencil enabled him to complete despite frequent intervals of illness. He devoted himself to his task with intense application. "Twenty minutes," he writes from South Africa in the middle of the stifling summer, "is my fair allowance for a drawing, with all its microscopical analysis."
From his letters, and from the reminiscences of persons who remember him, one gathers that Harvey was a very lovable sort of man. Shy and retiring, and diffident as to his own powers, with a deeply affectionate nature, he was equally prone to singing the praises of his friends, and to disparaging himself. "If I lean to glorify any one," he writes to William Thompson of Belfast, "it is Mrs Griffiths, to whom I owe much of the little acquaintance I have with the variations to which these plants [the seaweeds] are subject, and who is always ready to supply me with fruits of plants which every one else finds barren. She is worth ten thousand other collectors." Writing of Harveya, a genus of South African Scrophularineae which Hooker had just named in his honour, he comments, "'Tis apropos to give me a genus of Parasites, as I am one of those weak characters that draw their pleasures from others, and their support and sustenance too, seeing I quickly pine, if I have not some one to torment." He in his turn loved to commemorate his friends, or others in whom he felt an interest, by naming after them new genera of plants—Apjohnia, Areschougia, Ballia, Backhousia, Bellotia, Bowerbankia, Drummondita, Curdiea, Greyia, Mackaya, and many others. The names of some of his favourite authors are similarly enshrined, as Crabbea, Evelyna. Indeed, when at Niagara he saw an inscription to a young lady who fell over the cliff when gathering flowers—
Miss Ruggs at the age of twenty-three
Was launched into eternity,