1 66 



NA TURE 



[Dec. 1 6, 1886 



was set in torsional vibration, and tlie logaritlimic decre 

 determined with tlie same precautions as before. 

 Tlie following were the results : — 



Yibration-period Coefficient of viscosity Temperature in degrees 



in seconds of air in C.G.S. units, ;u Centigrade 



3-6038 ... O-000I77O8 ... I2'225 



8-8656 ... 3-00017783 ... i3'o75 

 In these experiments the loss of energy arising from the friction 

 of the air may be characterised as being due to the drag^ng of 

 the air, and it is very remarkable that there should be such close 

 agreement in the values of ft. as determined by this and the 

 previous methods. The mean value of the coefficient of viscosity 

 of air obtained by this method is 0-00017746 at a temperature of 

 l2°-650 C, and the mean value deduced from the previous 

 experiments when proper correction has been made for the rota- 

 tion of the spheres and cylinders about their axes is [0-00017711 

 at a temperature of n°'79 C. ' 



November 25. — " On the Structure and Life-History i Enty- 

 loma Ranunculi (Bonorden)." By H. Marshall Ward, M.A., 

 F. L. S. , Fellow of Christ's College, Cambridge, and Professor 

 of Botany in the Forestry School, Royal Indian College, 

 Cooper's Hill, 



The author found plants oi Ranuncubis Ficaria, the leaves of 

 which were spotted with white patches ; the white patches 

 spread from leaf to leaf, and the disease assumed the nature of 

 an epidemic over a given area under examination. The rise, 

 progress, and climax of the disease were observed both on 

 isolated plants and in the open country, and the nature of the 

 lesions in the leaves was made out. Some plants were found to 

 succumb more rapidly ; the evidence supporting this conclusion 

 was given, and the circumstances to which the differences are 

 due explained. 



The white disease-spots contain the mycelium of Entyloma 

 Ranunculi, and the resting-spores of this fungus (one of the 

 UstilagineEe) were observed on it. The mycelium is very delicate 

 and septate, and runs in the middle lamellaa between contiguous 

 cells. The white powder on the outside of the disease-spot 

 consists of conidia, very like those of some Ascomycetes. The 

 author examined the anatomical connection between the conidia 

 and the resting-spnre-, and >howed that the conidia re.iUy belong 

 to the same mycelium — in other words, the conidia are a second 

 kind of spore of the Entyloma. 



Even more important is the germination of these conidia : 

 this has not been before observed in any Entyloma. The ger- 

 mination was traced step by step, not only on glass shps, but 

 also on the living plant. Artificial infections were made, and it 

 was shown how the germinal hyphfe entered the stomata, and 

 produced a mycelium exactly like that in the disease-spots first 

 investigated ; not only so, but the rating-spores of the Entyloma 

 were produced on this myciliuni, thus placing beyond doubt the 

 connection of the two spores. The time occupied in infection 

 was also determined in many cases. Moreover, all the 

 symptoms of the disease produced by infection with the conidia 

 were as before. The paper was illustrated by diagrains, and 

 specimens of the fungus were exhibited under the microscope. 



Mathematical Society, December 9. — Sir T. Cockle, 

 F.R.S,, President, in the chair,— Prof. D. Y. Kikuchi, of 

 Tokio, was elected a Member, and Mr, F. S. Macaulay ad- 

 niitted into the .Society. — The following communications were 

 made : — The linear partial differential equations satisfied by pure 

 ternary reciprocants, by E. B. Elliott. — Circular notes, by R. 

 Tucker. — The problem of the duration of play, by Capt. Mac- 

 mahon, R.A. — Note on two annihilators in the theory of elliptic 

 functions, by J. Griffiths. — Mr. Hammond spoke upon the sub- 

 ject of Capt. Macmahon's communication at the November 

 meeting. 



Linnean Society, December 2. — William Carruthers, 

 F.R. S., President, in the chair. — The following gentlemen were 

 elected Fellows of the Society, Messrs. J. W. Willis Bund, 

 Arthur Dendy, Anthony Gepp, Tokutaro Ito, F. Krause, 

 F. M. Lascelles, Fred Sander, R, von Lendenfeld, John Sam- 

 son, Harry S. Burton, A, W. Sutton, and Chas. W. Wilson ; 

 afterwards Mr, Geo. Sim was elected an Associate. — The Pre- 

 sident read a letter from the Rev. M. J. Berkeley, concerning 

 the death of his old and respected co-worker on fungi, Mr. C. E. 

 Broome. — Mr. G. Maw exhibited ten photos of living Narcissi, 

 made in the Riviera in 1870. He afterwards gave a short 

 account of the North African and South Spanish Narcissi as 



observed by him on a recent visit thither. The Narcissus 

 fapyraceiis extends as far r.s Fez, in Morocco ; south of that 

 N. suh-Brotissoneti takes its place, and is found from Saffi to 

 Mog.ador, Incidental allusion was made to the smallest of the 

 while forms of N. Taczetta in the Island of -iTeneriffe, Of the 

 autumnal specie^, reference was made to iV, nudijiorus, which 

 had been lost sight of for half a century, but was re-discovered 

 by Mr, Maw in 1S83 in the neighbourhood of Gibraltar, and 

 again recently near Tangier, A hybrid between N, viridijiorus 

 and N. serotinus was found by him close to Gibraltar, and 

 a series of hybrids between N. viridijiorus and N. elegans were 

 got in North Morocco. Mr. Maw stated that N. serotinus was 

 limited. to the south of Spain, and N. eleqans io the Morocco 

 coast, the latter plant bearing true leaves. He mentioned the 

 abundance in flower and fruit of a small Amaryllid, Tapeinanthus 

 humilis, Herbert, as occurring eight miles south of Tangier. — 

 Dr. Day read a paper on the Lochleven trout, which is the form 

 that has been utilised by Sir James Maitland at Howietoun, 

 where the elevation is similar to that of their original home, 

 distant about 25 miles. These fish are known by their numerous 

 cEECal appendages, and up to their fourth or fifth year they are 

 of a silvery gray, witli black, but no red, spots. .Sub, eqiiently 

 they become of a golden purple with numerous black and red 

 spots. Undergrown ones take on the colour of the burn trout. 

 Remove these fish to a new locality, and they assume the form 

 and colour of the indigenous trout. In 18S3 a salmon parr and 

 Lochleven trout were crossed, and the young have assumed the 

 red adipose dorsal fin, and the white-edged margins to the 

 dorsal and ventral, aho the orange edges to both sides of the 

 caudal — all colours found in the brook trout, but not in the 

 salmon or Lochleven trout. The maxilla in this form not extend- 

 ing to behind the eye, the absence of a knob on the lower jaw 

 in old breeding males and the difference in the fins from those of 

 Salmo fario were shown to have been erroneous statements, — 

 A paper was read on Hermann's "Ceylon Herbarium" and 

 Linnjeus's " Flora Zeylanic.a," by Dr, Henry Trimen, The col- 

 lection of dried plants .and the drawings of living ones made in 

 Ceylon by Paul Hermann in the latter half of the seventeenth 

 century possess a special interest as being the first important 

 instalment of material towards a knowledge of the botany of the 

 East Indies ; but Hermann himself, who died in 1695, published 

 very little of this material. .Some of his manuscripts were subse- 

 quently printed by W. Sherard, including a catalogue of the 

 herbarium, as then existing, under the title of " Museum 

 Zeylanica" (1717). This herbarium was lost sight of till 1744, 

 when it was recognised by Linn^us in a collection sent to him 

 from Copenhagen. After two years work at it, Linnajus pro- 

 duced in 1747 his "Flora Zeylanica," in which all the plants 

 that he could determine are arranged under his genera. At that 

 date Linna;us had not initiated his binomial system of nomen- 

 clature ; but in his subsequent systematic works he quoted the 

 numbers of the " Flora Zeylanica," and thus Hernrann's speci- 

 mens became the types of a number of Linnceus's species, for the 

 most part additional to those in his own herbarium in the pos- 

 session of the Linnean Society. 



Zoological Society, December 7. — Prof, W, H. Flower, 

 F. R. S., President, in the chair, — Prof. Bell exhibited and made 

 remarks on a specimen of a rare Enlozoon {Ticnia nana) from 

 the human subject. — Mr. Tegetmeier exhibited and made 

 remarks on a pair of antlers of a Deer, said to have been recently 

 obtained in the Galtee Mountains in Ireland. They appeared 

 to be those of the Elk (Alces machlis). — Mr. Frank E. Beddard 

 read a paper on the development and structure of the ovum in 

 the Dipnoan fishes. The present communication was a con- 

 tinuation of a research into the structure of the ovary in Froto- 

 fterus. The author, besides being able to give a more complete 

 account of the ovarian ova of Frotopterus, was also able to sup- 

 plement this account with soine further notes respecting the 

 structures observed in the ovary of Ceratodus. — Mr, A. Smith- 

 Woodward read a paper on the anatomy and systematic position 

 of the Liassic Selachian, Squaloraja polyspondyla. After a brief 

 notice of previous researches, the author attempted an almost 

 complete description of the skeletal parts of Squaloraja, as 

 revealed by a f.ne series of fossils in the British Museum. He 

 confirmed Davies's determination of the absence of the cephalic 

 spine in certain individuals (presumably females), and added 

 further evidence of its prehensile character, suggesting also that 

 the various detached ex.amples afforded indications of one or 

 more new species. The author concluded with some general 



