this close approach to modern conceptions, he was not an evolutionist.  When, in public, he expressed deliberate convictions, these convictions were against the general idea of evolution, until very shortly before 1859.  In this opposition he was supported partly by the critical scepticism of his mind, which in all things made him singularly unwilling to accept any theories of any kind, but chiefly from the fact that the books of the two chief supporters of evolutionary conceptions impressed him very unfavourably.  Huxley writes: 

“I had studied Lamarck attentively, and I had read the Vestiges with due care; but neither of them afforded me any good ground for changing my negative and critical attitude.  As for the Vestiges, I confess that the book simply irritated me by the prodigious ignorance and thoroughly unscientific habit of mind manifested by the writer.  If it had any influence on me at all, it set me against evolution; and the only review I ever have qualms of conscience about, on the ground of needless savagery is one I wrote on the Vestiges while under that influence.  With respect to the Philosophie Zoologique, it is no reproach to Lamarck to say that the discussion of the species question in that work, whatever might be said for it in 1809, was miserably below the level of the knowledge of half a century later.  In that interval of time, the elucidation of the structure of the lower animals and plants had given rise to wholly new conceptions of their relations; histology and embryology, in the modern sense, had been created; physiology had been reconstituted; the facts of distribution, geological and geographical, had been prodigiously multiplied and reduced to order.  To any biologist whose studies had carried him beyond mere species-mongering, in 1850 one-half of Lamarck’s arguments were obsolete, and the other half erroneous or defective, in virtue of omitting to deal with the various classes of evidence which had been brought to light since his time.  Moreover his one suggestion as to the cause of the gradual modification of species—­effort excited by change of conditions—­was, on the face of it, inapplicable to the whole vegetable world.  I do not think that any impartial judge who reads the Philosophie Zoologique now, and who afterwards takes up Lyell’s trenchant and effective criticism (published as far back as 1830) will be disposed to allot to Lamarck a much higher place in the establishment of biological evolution than that which Bacon assigns to himself in relation to physical science generally—­buccinator tantum”.

On the other hand, Huxley’s friendship with Darwin and with Lyell began to make him less certain about the fixity of species.  He tells us that during his first interview with Darwin, which occurred soon after his return from the Rattlesnake, he