May 20, 1875] 



NATURE 



59 



mu't be taken into account in considering the action of the rays 

 of different refrangibility, and further, that the increased effect 

 due to red light may have been in part due to the concentration 

 of rays of low refrangibility which attends the use of glass 

 prisms, A diffraction spectrum might give a different result. 

 He added that when a ray falls on a surface capable of motion, 

 which reflects it, very little work is done, but if the surface 

 quenches the ray, motion is produced. He then thanked Irof. 

 Guthrie for his kindly remarks.— Prof. Comu, of the Jccole 1 oly- 

 technique, described his recent experiments on the determination 

 of the velocity of light. Hegave an account of the method of Fou- 

 cault, and exhibited the complete apparatus, including the arrange- 

 ment of mirrors for multiplying the distance traversed between the 

 two reflections from the revolving mirror (Nature, vol. xi. p. 274). 

 —Prof. Adams, vice-president, mentioned that M. Comu had con- 

 tributed in no small measure to the success which had attended 

 the formation in France of a society closely corresponding to our 

 British Association, and assured him that the Physical Society 

 felt grateful for his presence, as he could well understand the 

 difficulties with which the early days of such a society are beset. 

 — M. Comu stated, in answer to a question of Prof. G. C. Foster, 

 that he objected to the revolving mirror method, because the 

 distance to be traversed by the light was very small, and because 

 the path of the ray lay through a vortex of air produced by the 

 rapid revolution of the mirror. 



Royal Horticultural Society, April 7.— Scientific Com- 

 mittee. A. Grote, F.L.S., in the chair.— A communication 

 was read from W. Wilson Saunders, F.R.S., describing a 

 diseased condition of young poplars planted on the sides of roads 

 in Fast Worthing. The disease seems sooner or later to be fatal 

 to the tree, for he had not seen one tree attacked of which there 

 seems any chance of recovery. The trees are from twelve to 

 eighteen feet high, and with stems varying from five to seven 

 inches in diameter. The disease is most apparent in large, 

 rough, open wounds about the commencement of the lower 

 branches, and on the stem ; but upon closer examination 

 symptoms of the disease will be found all over the tree, even to 

 the tops of the branches. The disease seems to show itself at 

 first by a longitudinal fissure in the bark, which fissure is nearly 

 straight and but of little depth, having its lips slightly elevated 

 and reflexcd. At first the fissure does not penetrate the whole 

 depth of the bark, but, gradually deepening and extending in 

 length, the wood becomes exposed. This continues until the 

 wood is quite exposed, and in a branch of two years' growth the 

 disease assumes the appearance of a long open wound, exposing 

 much of the wood which the growth of the bark partially covers 

 up. Tracing the progress of the disease further, side fissures 

 will be seen producing the same results ; and these fissures, 

 running one into the other, break up the bark until occasionally 

 the disease extends all round the branch. When a branch gets 

 diseased, the portion above the wound dies. The disease is 

 often slow in progress, particularly when on the main stem, 

 large open wounds then appear, cf the same character as those 

 en the branches, exposing much of the wood, but having the 

 surrounding bark, although diseased and cracked, in a healthier 

 state.— Mr. M'Lachlan referred to a note in the report of Lieut. 

 Carpenter, of the American Geological Survey, in which it was 

 stated that the Colorado Potato Beetle was distributed by means 

 of seed potatoes, and that its absence in Utah and other parts of 

 California was to be attributed to the fact that it has not yet 

 been necessary to import seed potatoes.— :Mr. Hemsley sent a 

 turnip with a cavity in the interior of the root nearly filled by 

 leaves growing from the crown downwards and inwards. — Prof. 

 Thiselton Dyer exhibited under the microscope a portion of the 

 Plasmodium of Aithaliiim, showing the "streaming" move- 

 ments of the protoplasm of which it is composed. 



General Meeting.— W^ Burnley Hume in the chair.— The Rev. 

 M. J. Berkeley commented on the objects exhibited, including a 

 group of species of Drosera and Drosophyllum exhibited by 

 Messrs. Veitch. 



April 21. — Scientific Committee. — Andrew Murray, F.L.S., 

 in the chair. — The Chairman remarked that from his own obser- 

 vation there could be no doubt that the Colorado Potato 

 Beetle was perfectly able to live in the climate of Canada. — 

 Mr. Edmonds sent from the Gardens at Chiswick House 

 a basket of Pcziza lanuginosa.— "Dr. Masters exhibited shoots 

 of peach-trees which had been killed owing to having been 

 thickly painted with colza oil. — Mr. Wilson Saunders 

 communicated a note on a monstrous condition of the early 

 St. John's Cabbage. When the bed of cabbages was about 



at its best, a long, warm, very dry period was succeeded by 

 much rain. The sudden impulse given to vegetation by this 

 soon caused the solid heads of the cabbage to burst, and in a 

 few days a series of smaller, well-shaped, rounded, compact 

 heads were formed from the central axis of growth, closely 

 touching each other, and backed up by the leaves of the original 

 head, which remained green and full of sap. The number of 

 these smaller heads varied from three to six in each cabbage. — 

 Prof. Thiielton Dyer read an abstract from the Sitzimgsbericht 

 der Gesellschaft Naturforschender Freunde zu Berlin for Nov. 17, 

 1874, in which an account was given by Magnus of the produc- 

 tion of graft hybrids in the potato by Renter, the chief gardener 

 at Potsdam, in 1874. He used tbe white long Mexican and the 

 dark grey black kidney, both of which sorts had been intro- 

 duced from America by the Novara Expedition. A wedge- 

 shaped piece of the former, bearing an eye, was grafted upon 

 the latter. The graft hybrids exhibited an intermediate cha- 

 racter in form between the parents. They were broader and 

 thicker than the long thin Mexican, longer than the black 

 kidney. One of the potatoes also exhibited a blending of the 

 colours. The two ends were red, and the middle zone a greyish 

 yellow. The dark grey colour of the black kidney is produced 

 by the intense red sap in a layer of cells covered by the corky 

 rind. In a subsequent communication Magnus mentioned 

 similar experiments which had been made by Dr. Max Heimann, 

 and communicated to the botanical section ot the Schlesischen 

 Gesellschaft in the Sitzungsberichi for Nov. 19, 1872. Magnus 

 described similar results obtained by Dr. Neubert, of Stuttgart, 

 by herbaceous grafts of the stems. 



General Meeting.— W. Burnley Hume in the chair.— Prof. 

 Thiselton Dyer commented on the objects exhibited. 



Anthropological Institute, May 11.— Col. A. Lane- Fox, 

 president, in the chair.— Mr. Moncure D. Conway, M.A., read a 

 paper on Mythology. He maintained that the evolution of 

 mythology was the reverse of what the facts of physical evolu- 

 tion might suggest ; it was not from beneath upwards to higher 

 things, but rather from the grand in nature that the human mind 

 had arrived at the association of mystical meanings with the 

 stock and stone, plants and animals, which figured so largely in 

 popular mythology. Sacred animals were consecrated as syni- 

 bols of the higher phenomena. Flowers and plants derived their 

 potency from connection with solar or lunar influences, still 

 represented in the belief that to be healing they must be gathered 

 at certain holy times or at certain phases of the moon. It was 

 also maintained that the gods were personifications of power, and 

 unmoral ; they were gradually divided into good and evil, the 

 demoniac powers being for a long time not diabolical, but per- 

 sonifications of hunger, thirst, and the dangers and impediments 

 of life. The idea was combated that men had ever worshipped 

 purely evil powers. The legend of Eden was held by Mr. Con- 

 way to be inexplicable by Semitic analogues. In India were 

 found the myths of serpent-guarded trees and the apple of im- 

 mortality, and the curse on the serpent which had puzzled theo- 

 logians was explained by the theory of transmigration.— A paper 

 by Rev. A. H. Sayce, M.A., was read, on Language and Race. 

 The author held that the fallacy of language as a sure and certain 

 test of race is one to which few modem philologists would com- 

 mit themselves. There was no assertion which could be more 

 readily confronted with history, or, when so confronted, more 

 clearly be demonstrated to be false. Society implied language, 

 race did not ; hence, while it might be asserted that language is 

 the test of social contact, it might be asserted vdth equal pre- 

 cision that it is not a test of race. Language could tell us 

 nothing of race. It did not even raise a presumption that 

 the speakers of the same language were all of the same origin . 

 It was only necessary to look at the great States of Europe, with 

 their mingled races and common dialects, to discover that lan- 

 guage showed only that they had all come under the same social 

 influences. Race in philology and race in physiology meant 

 very different things.— Mr. A. W. Franks, F.R.S., exhibited an 

 inscribed wooden gorget from Easter Island. 



Entomological Society, May 3.— Sir Sidney Smith Saunders 

 C M G , president, in the chair.— The President exhibited male 

 specimens of Styhps, taken by himself in the pupa state, on 

 Andrena atriceps, at Hampstead Heath, on the 6th, 9th, and 

 17th April last. Mr. Enoch, who had been there on the 6th at 

 an earlier hour (between nine and ten o'clock) had been still more 

 successful, having captured 17 males, one of which, however, 

 was taken after 2 P.M. The President drew attention to th« 

 remarkable difference observable in the cephalothorax of the 



