128 



NATURE 



[December 7, 1893 



but whence do they themselves originate? And this 

 question still remains unsolved. The polyps are 

 observed to increase by budding, but they never form 

 clusters of more than four " persons." How do they 

 become distributed over the under surface of nearly 

 all the floating leaves in the tank? How do they get 

 carried to an outside reservoir? Is it not improbable 

 that they would continue year after year to propagate 

 t^emselves by budding as polyps, and in the summer to 

 throw off successive crops of ;;m/^ medusae ? It is possible 

 that this is the whoie history, but not quite probable. 



In any case, however, the existence of the minute 

 polyps attached to water-plants is sufficient to explain 

 the introduction of the jelly-fish to Sheffield. It also is 

 sufficient to explain the original introduction of the jelly- 

 fish to the Regent's Park, since in 1878 (two years before 

 the first discovery of the jelly-fish) specimens of a re- 

 markable water-plant {Pontederia) were brought from 

 Brazil by a lady and presented to the Botanical Society, 

 and placed in the Victoria Regia tank. 



A new interest has recently been added to that already 

 attaching to Limnocodium by the description of another 

 fresh-water jelly-fish, the Limnocnida Tangaiiyisice. This 

 remarkable form was worked out in my laboratory in 

 Oxford during last winter by Mr. R. T. Giinther, who 

 received the specimens from his father, Dr. Giinther, 

 F.R.S., of the British Museum. Dr. Giinther had written 

 to the Mission on Lake Tanganyika in order to procure 

 the specimens. Individuals of three kinds are described 

 by Mr. Giinther, viz. males, females, and a-sexual in- 

 dividuals which produce crops of buds on the manu- 

 brium (see his papers in the A7tn. and Mag. Nat. Hist., 

 1893, and in the forthcoming number of the Quart. - 

 Journ. Micros. Science). Whilst differing greatly from 

 Limnocodium in most respects, Limnocnida agrees with 

 it, in a most extraordinary way, in the minute structure 

 of the marginal sense-organs. No light is thrown by 

 Limnocnida on the problem of the life-history of Limno- 

 codium. 



I subjoin a list of dates in reference to the history of 

 Limnocodium, and may add that the columns of Nature 

 already contain numerovs communications relative to 

 it, viz. in vol. xxii. (1880), pp. 147, 177, 178, 190, 218, 

 241, 290, and in vol. xxxi. p. 107. 



1880. — June 10, first observed in Regent's Park ; remained 

 six weeks. 



1881. — June 12 ; reappeared ; remained five weeks. 



1882. — None observed. 



1883. — April 28 ; twelve weeks. 



1884.— April 27 ; twelve weeks (?). 



1885. — April 5 (no record of duration). 



1886. ^August 7 (no record of duration). 



1887. — End of May (no record of duration). 



1888. — May 10 (no record ; very few observed). 



1889.— None. 



1890. — New tank constructed and stocked ; July 10 a few. 



1891. — None. 



1892.— None. Plants sent to Sheffield April 4. 



1893. — None in London. Plants again sent, April 7, to 

 Sheffield. 



1^93- — June 7 to mid- October, large numbers observed in 

 tank at Sheffield. 



Hydroid trophosome discovered by Bourne in winter of 1884. 



Production of medusae by hydroid, observed by Fowler, in 

 May, 1888. E. Ray Lankester. 



DEA TH OF PROF. TYNDALL. 



A NOTHERof our " Scientific Worthies "has/' crossed 

 -^~^ the bar," leaving behind an honoured name and 

 works that will perpetuate his memory. On Monday 

 evening Prof. Tyndall passed away at his residence, near 

 Haslemere. For some time previous he had been suffer- 

 ing from insomnia and rheumatism, and very unfavour- 

 able symptoms set in on Monday morning. He quickly 



NO. 1258, VOL. 49] 



became unconscious, and except for a brief interval at 

 midday, remained in this state until half-past six o'clock,, 

 when a peaceful change from life to death took place. It 

 appears that the cause of death was an overdose of 

 chloral, which Prof. Tyndall took as a sedative against 

 insomnia. He had been in the habit of taking narcotics 

 for several years past in order to overcome the sleepless- 

 ness from which he suffered. On Monday about the 

 usual quantity was administered to him, but his greatly 

 weakened condition was unable to bear so much. The 

 inquest on the body, which was considered necessary by 

 the doctors, was held yesterday. 



A detailed account of Tyndall's life was given in these 

 columns in August, 1S74, so it is only necessary to trace 

 now a brief outline of his career. He was born in 1820, 

 at Leighlin Bridge, near Carlow, in Ireland. But 

 it was not until 1S47 that he began his career as a 

 teacher of science, by accepting a post in Oueenwood 

 College, Hampshire, where Dr. Frankland was chemist. 

 A year later the two friends did what every young man 

 of science should do, if possible — they went together to a 

 German University, the University of Murburg, Hesse 

 Cassel, rendered celebrated by Bunsen and others ; and 

 to Bunsen, whose lectures he attended, and in whose 

 laboratory he worked, Tyndall was never tired of express- 

 ing his obligations. He was at Murburg when Knob- 

 lauch, preceded by a distinguished reputation, and 

 accompanied by a choice collection of instruments, went 

 there as Extraordinary Professor. Subsequently, in con- 

 junction with Knoblauch, Tyndall carried on his " classic " 

 inquiries in connection with diamagnetism, afterwards 

 prosecuting his research in the laboratory of Prof Magnus 

 at Berlin. In i85r his life-long friendship with Prof. 

 Huxley commenced, and in the following year he was 

 elected a Fellow of the Royal Society. In February, 

 1853, he gave the first of his eloquent Friday evening 

 lectures at the Royal Institution. Shortly afterwards, at 

 the proposal of Faraday, he was appointed Professor of 

 Physics in the Institution, a post from which he retired in 

 1887. The managers and members of the Institution 

 marked their sense of the benefits he had conferred upon 

 it by electing him as Honorary Professor, a title pre- 

 viously borne by Davy and Brande, and by calling one of 

 the annual courses of lectures " The Tyndall Lectures." 

 His bust was also placed in the Institution in memory of 

 his relations with it. 



A complimentary dinner was given to Tyndall on the 

 occasion of his retirement from the Chair of Physics in 

 the Royal Institution. The body of eminent men which 

 met at the dinner was such as has seldom if ever been 

 brought together to do honour to a man of science, and 

 when the chairman, Sir George Stokes, the then President 

 of the Royal Society, gave voice to the desire of the 

 company that their guest should long enjoy the leisure 

 which he had so well earned, it was not thought that after 

 but six years of rest from labour he would be called away. 

 The speeches made at the dinner are reported in Nature, 

 vol. xxxvi. p. 222, and they show the high regard in which 

 Tyndall was held throughout the world of science, art, 

 and letters. In responding to the toast of the evening,, 

 he gave an account of his life, including in his speech 

 the following true remarks : — " To keep technical educa- 

 tion from withering, and to preserve the applications of 

 science from decay, the roots of both of them must be 

 imbedded in the soil of original investigation. And here 

 let it be emphatically added, that in such investigation, 

 practical results may enter as incidents, but must never 

 usurp the place of aims. The true son of science will pursue 

 his inquiries irrespective of practical considerations. He 

 will ever regard the acquisition and expansion of natural 

 knowledge — the unravelling of the complex web of nature 

 by the disciplined intellect of man, as his noblest end, and 

 not as a means to any other end." This was the kind of 

 spirit that actuated Tyndall throughout his career. It 



