When the hot weather came, we left Messina for Riva, a delicious summer resort on the shores of the Lake of Garda. There, Metchnikoff wrote his first memoir on the reaction of inflammation and on the digestion of microbes by the mesodermic cells of lower invertebrates. On the way back to Russia through Vienna, he went to see the Professor of Zoology, Claus; he found other colleagues with him and expounded his theory to them. They were much interested, and he asked them for a Greek translation of the words "devouring cells," and that is how they were given the name of _phagocytes_. Claus asked him for his memoir for the Review which he edited and in which it appeared soon afterwards, in 1883.[16] The new-born "phagocyte theory" was thus very well received by naturalists and by Virchow, the father of cellular pathology. [16] _Arbeiten des zool. Inst. zu Wien_, Bd. v. Heft ii. p. 141. "Untersuchung über die intracelluläre Verdauung bei wirbellosen Tieren," E. Metchnikoff. Having returned to Russia, we went to the country, where Elie had to attend to family business; nevertheless, he continued his researches in every leisure moment. He had observed in Echinoderma that, during the transformation of their larvæ, the parts becoming atrophied were englobed by mesodermic mobile cells. In those observations he was delighted to have found an example of _physiological inflammation_, _i.e._ one which presented itself in normal and non-morbid conditions. He thought he might observe it also during the metamorphosis of the tadpole into a frog, whilst the tail was being atrophied. But he found that, instead of the leucocytes of the blood, certain cells from the muscular tissue were those which devoured the enfeebled elements of the tail; he thus learnt that phagocytes might be, not only the white blood corpuscles, but other cells of mesodermic origin.[17] [17] It was only in 1892 that he completed and developed his observations. He found that the cells of the sarcoplasma of the muscular tissue devoured its contractile part, the myoplasma. In autumn 1883 he read his first paper on phagocytosis to a congress of physicians and naturalists at Odessa.[18] He compared the phagocytes to an army hurling itself upon the enemy and looked upon the phagocytic reaction as a defensive force of the organism. [18] This paper was entitled "Forces curatives de l'organisme." In that paper itself and from that moment onwards, the trend of his ideas towards optimism becomes visible. By discovering the phagocytic reaction of the organism, he made a first breach in his philosophy of human nature, hitherto so pessimistic; he discovered within it a salutary element which could be utilised by science to combat its discords. He began to have some faith in the power of knowledge, not only for this struggle, but also for the establishment of a rational conception of life in general. Thus he said in his paper to the Odessa Congress: