350 



SCIENTIFIC NEWS. 



[April 13, i5 



are extirpated on account of their beauty. Careful exami- 

 nation will show that such is not the case. Certainly 

 lilies of the valley growing in our woods are carried off 

 for sale wherever seen. But a far wider devastation is 

 experienced by the groundsel, the thistle, the dock, and 

 the dandelion. Every gardener, from the extensive 

 nurseryman to the humblest amateur, wages war on 

 these weeds unceasingly. So does every farmer. They 

 have also their natural enemies among birds and insects. 

 But instead of decreasing we may feel thankful if they 

 are not gaining ground. A persecution a hundred-fold 

 more severe than that which overpowers the lily of the 

 valley leaves them unhurt. 



It is surely a difficult task to say why and how tenacity 

 and the power of multiplication are thus apparently at 

 least, preferentially linked with ugliness and hurtfulness. 



The main peril of naturalising any species lies in the 

 circumstance that we can rarely judge how its habits and 

 its powers may be modified by novel surroundings. We 

 know now that the diet and the rate of increase of an 

 animal are not constant points immutably fixed, but are 

 open to change. If a destructive insect be conveyed to a 

 climate where the summer is longer and less fickle, it 

 may produce an additional brood of descendants every 

 season. European entomologists are apt to smile at the 

 notion of Cbcerocampa celerio as a vineyard pest. Yet 

 this result has been reached in California. 



A still more frequent cause is that a species in its 

 original home may have been kept in check by some 

 parasite or other destroj^er. But when transferred to 

 another hemisphere these enemies may not have accom- 

 panied it. Hence its increase is for a time, at least, un- 

 bounded. Not a few of the most destructive insects in 

 the Atlantic States of the American Union are old 

 familiar denizens of Europe, and have here done com- 

 paratively little damage. But when introduced into 

 fresh fields and pastures new they have multiplied in a 

 manner previously unimagined. 



Herewith is connected a curious fact : — The animals, 

 the plants, and the diseases of the eastern continent have 

 a much greater tendency to become cosmopolitan than 

 those of America and Australia. A goodly number of 

 European plants — substantially all of them vile weeds 

 — have reached California, Australia, and New Zealand, 

 have there become wild, and are to a lamentable extent 

 displacing the much more interesting native vegetation. 

 But the instances of an American plant having become 

 naturalised in any part of Europe are rare. And so far, 

 we think that no Australian plant has penetrated into 

 Europe save under cultivation. Here, of course, the 

 winter's cold is an additional hindrance. In explanation 

 of this unpleasant fact it is said that the flora of the great 

 Eastern continent is composed of the survivors of a 

 struggle for existence more intense, prolonged, and com- 

 plicated than can have raged in other parts of our earth. 

 Forms which have emerged victorious from such a con- 

 test have naturally great odds in their favour when 

 brought in contact with the flora of New Zealand, Aus- 

 tralia, or even America. Very similar is the case with 

 the fauna. 



(To be concluded.) 



♦-^S^i"^?^^ — 



Spectrum of Potassium. — M. H. Deslandres (Comptes 

 Rendiis) has determined the wave-lengths of the rays 

 of the spectrum situated in the extreme red. The stronger 

 is 766'3o, and the fainter ']6<)-()t,. 



"SHOWERS OF BLOOD." 



IN a recent session of the Paris Academy of Sciences 

 M. Daubr^e read a letter from M. Delauney con- 

 cerning an alleged shower of blood observed in Cochin 

 China on December 13th last. 



M. Thoraude, "phu" of the district of Tay-Ninh, 

 writes : — " On December 13th last I was returning with 

 my family to Tay-Ninh in a public conveyance, along 

 with four native passengers and two children. About 

 4 p.m., whilst at a distance of five miles from Tay-Ninh, 

 the conductor turning to me asked, in an angry tone, why 

 I had scattered over his clothing blood from a cut in my 

 fingers. Annoyed at this unfounded accusation, I 

 looked at my hands, and saw, to my no small surprise, 

 the fingers all stained with blood. At this sight I fancied 

 that I must in reality have cut my fingers on some sharp 

 object without being aware of it. But on wiping my 

 hand with a handkerchief I saw that there was nothing 

 of the kind. 



I asked the other passengers if they knew how the 

 blood had got upon my fingers, but they knew no more 

 than myself. On examining my clothing and looking 

 about, I found a considerable number of small spots, 

 which, upon my black coat, appeared black, but upon 

 touching them I saw, as did the other passengers, that 

 they had the appearance of blood slightly curdled. 



Some minutes after, one of the passengers, named 

 Pham-thi-Le, saw the face of her child besprinkled with 

 drops of blood. It was the same with the white dress 

 of my little boy, and with my umbrella, which had been 

 placed behind the conductors. One of them, who was in 

 front of us, perceived a prodigious number of blood-spots on 

 his white jacket. The next morning when I wished to 

 collect these blood-spots for examination I found that the 

 garments had already been washed. 



As for the trees at that point of the road where this 

 phenomenon was observed, there were three so-called 

 " ven-ven," two banyans, and one " cay-dal." Whilst 

 the blood-drops fell, the sky was completely overcast. 

 The passengers observed no rain, but they agree that the 

 ground was moist." 



A second letter from a native of rank, named Lanh, 

 also announced a shower of blood which had fallen at 

 the same time at Hiep-Ninh, a place at no great 

 distance. 



M. Delauney added to these notes the announcement 

 that he was about returning to France, and should bring 

 with him the umbrella of M. Thoraude, to admit of an 

 examination of the alleged blood spots. No similar 

 phenomenon, it appears, had been previously observed in 

 Cochin-China. 



In Europe and Western Asia, however, the case is 

 different. In the records of classical antiquity, in the 

 chronicles of the dark ages, and in popular sagas down to 

 the seventeenth century, rains of blood figure not unfre- 

 quently. Obsequens, in his work on "Prodigies," 

 which was republished in 1555, speaks of several showers 

 of blood which he had found described by ancient his- 

 torians. At Saturnia it rained blood in the city foi 

 three days, so there was also a rain of blood on the 

 murder of Tatius. Such phenomena were, of course, re- 

 garded as dreadful portents, and are said to have occa- 

 sioned no little consternation. 



But in what light are we to view them ? Are these 

 traditions simple, baseless falsehoods, or are they records 

 of fncts ? There can be no hesitation in saying, neither 



