LIXNEAN SOCIETY OF LO]SrDOJSr. 53 



throughout the animal kingdom from the Protozoa to man; and 

 in a later work on Iininuiiity (1901) he gave a complete exposi- 

 tion of his theories of the means of defence of animals against 

 infective agents, reviewing all the modern work on nafural and 

 acquired immunity and on toxins and antitoxins. It was not 

 without a struggle that Metchnikoff established his views ; but 

 they ai'e now generally accepted, and form the basis of most of 

 the new develo|)ments iu the pathology of intVctious diseases. 



Metchnikoif's first wife died early, and in 1875 he married Olga 

 Belocagitoff, a highly gifted lady, not only an accomplished linguist 

 and artist, but also a zoologist of distinction. To the last Metch- 

 nikoff pursued his studies with untiring energy at the Pasteur 

 Institute in Paris, of which he had become Professor and Sub- 

 director. In his later days he turned his attention to the 

 prolongation of human life by the control of the putrefactive 

 processes in the intestine. Though he cannot be said to have 

 successfully solved the difficult problems he then attacked, yet the 

 new light he threw on the subject may enable others to advance 

 further along the path he so boldly opened out. [E. S. G.] 



The practical retirement of Professor Daniel Oliver, LL.D., 

 P.R.S., from active botanic work at the age of sixty, has restricted 

 the number in this Society to whom the news of his death, at the 

 advanced age of 8(3, has come with a pang of regret, though this 

 diminished band will ever recall the late professor as an example 

 of strenuous and accurate work, and as adding greatly to the 

 influence of Kew under the directorship of the Hookers. 



Daniel Oliver was born at Newcastle-on-Tyne, on the 6th 

 February, 1830, and his father and grandfather bearing the same 

 christian name, he was styled " tertius " in his earlier papers. He 

 was educated at the Friends' School, Wigton, and there showed a 

 marked interest in field natural history, and a wider scope was 

 aiforded him on his joining the Tyneside Naturalists' Field Club 

 (now the Natural History Society of Northumberland and Durham), 

 where he came into contact with the naturalists Albany & John 

 Hancock, J. Alder, Sir W. C. Trevelyan, and H. Tuke Mennell. 

 Later he lectured on Botany at the Medical School of the 

 University of Durham, an early initiation into his after-life work. 

 His first printed paper came out in the ' Phytologist ' under the 

 editorship of Edward Newman, a modest contribution of less than 

 a page, "List of a few plants found in liouldersdale and Teesdale, 

 together with the Formations on which they were found," op. 

 cit. ii. (1847) p. 986, which gives an early intimation of ecology, a 

 department which has so greatly developed in our days. Three 

 successive short articles followed in the same medium, " Note on 

 Serratula tinctoria, Alsine stricta, and a species of Woodsia," iii. 

 (1850) p. 775, and "Notes of a botanical ramble in Ireland last 

 autuu]n," iv. (1851 ) pp. 125-128. He says i]i the last paper, "I 

 have already recorded Spen/ula suhtdata, JSfaiasfle.vilis, and one or 

 two [other plants]. It is very likely that the Kaias may be found 



