August 21, 1919] 



NATURE 



483 



enables it to adapt itself to the most diverse con- 

 ditions, and a strongs capacity for synthesis. These 

 symbiotic bacteria come in with the food from the 

 extra-orgfanismal environment, and, though the 

 partnership they form is usually indissoluble, they 

 may in certain circumstances rejoin their wild 

 relatives and live an independent life. 



Every naturalist knows that lichens are double 

 organisms, due to the symbiosis of algoid and 

 fungoid partners, which form a very effective 

 unity. Prof. Portier maintains that all organisms 

 except bacteria have in a similar fashion a dual 

 nature. A theory somewhat like this was pro- 

 pounded by Mereschowsky in 1910. But if all 

 cells are thus dual, why, one hastens to ask, have 

 ; not the ubiquitous, syjcabiotic, intra-cellular bac- 

 teria been seen before? The answer is that they 

 have been often seen, but persistently misinter- 

 preted. They are the components of the mito- 

 chondrial apparatus, those minute formed bodies, 

 with many an alias, which have been described 

 in the cytoplasm of all sorts of cells. It is true 

 that these mitochondria have often been credited, 

 with more or less probability, with a definite func- 

 tional r6le in the metabolism of the cell, a r6\e 

 differing from cell to cell; but are not the sym- 

 biotes very plastic? Prof. Portier is good- 

 humoured enough to quote the paradox that a 

 theory is not of value unless it can be demon- 

 strated false. We have no hesitation in prophesy- 

 ing that his theory will attain that value — which 

 is just what he would have said himself a few 

 years ago. We are bound to admit that the 

 author is a downright good sportsman. 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for 

 opinions expressed by his correspondents. Neither 

 can he undertake to return, or to correspond with 

 the writers of, rejected manuscripts intended for 

 this or any other part of Nature. No notice is 

 taken of anonymous communications.] 



The Magnetic Storm of August 11-12, 1919. 



>\'E of the very great magnetic storms, the most 

 violent recorded at this observatory since that of 

 September 25, 1909, commenced quite suddenly at 

 6.50 G.M.T. on August 11 from a very slightly 

 agitated normal curve in both the elements of 



, declination and horizontal force. The H magnet 



^increased sharply by 847 (ly— lo-'' C.G.S. unit), and 

 the D magnet swung 10' to the west. The direction 

 of motion in each element was immediately reversed, 



■ with a very rapid decrease of 113 7 in H, and a 

 swing in D, equally rapid, to the east of 16'. After 

 a few very rapid swings the spot of light due to 



j, H decreasing went off the recording drum at 7 a.m., 

 and remained off until it returned at 7.24 G.M.T. 

 At 8.12 G.M.T. H increased rapidly, the range of 



I' the swing exceeding 4467. At 8.50 G.M.T. it again 

 ■decreased rapidly, the spot of light remaining off the 

 recording drum until 9.43 G.M.T. These oscilla- 

 tions in H were accompanied by rapid swings in D. 

 After its sudden increase and decrease at the 

 beginning of the storm it swung 60' to the west. At 

 .8.52 G.M.T. it was 50' in the opposite direction. 

 The extreme range in D during the storm was no', 



NO. 2599, VOL. 103] 



and of H, since the spot of light travelled off the 

 drum on either side, greater than 7807. 



The greatest phase of the storm was between the 

 hours 14 and 20 G.M.T. on August 11. The spot 

 of light with increasing H was twice off the drum, 

 from 15.36 to 16.10 and from 16.20 to 16.38 G.M.T. 

 At 20 G.M.T. the oscillations of H were less rapid, 

 but thev recommenced, after a comparative lull, at 

 0.50 G.M.T. on August 12. At 1.38 G.M.T. a fine 

 peak of decreasing H began, which was followed by 

 a peak of increasing H at 3.15 G.M.T., the total 

 range being 404 7. Corresponding with this movement 

 D showed a very fine peak of swing to the west, 

 with a range of 66', at 1.48 G.M.T. These oscilla- 

 tions in both elements, particularly at the beginning 

 and at the maximum phase of" the storm, were 

 extremely rapid. 



These rapid oscillations were succeeded for a 

 period of about five hours by a violent shivering of 

 relatively small amplitude, but of great rapidity, in 

 both H and D. This phenomenon of so marked a 

 type I cannot recall to have seen in former storms. 

 After this, at 8.30 G.M.T., August 12, the swings 

 became slower and smaller in amplitude on the whole, 

 until the storm died quite abruptly in H, and less 

 marked, though abrupt, in D, at 19 G.M.T. on 

 August 12. 



The Times for August 12 announced that the 

 Minister of the Interior in Spain had notified the 

 Press of a breakdown in telegraphic and telephonic 

 communication on the preceding day. The postal 

 authorities in this district were also inconvenienced 

 on the same day by earth currents. Needless to 

 add that the solar surface has been greatly disturbed 

 by sun-spots lately. 



I looked out for ,a possible display of aurora en 

 the night of August 11, but the brightness of the 

 moon effectually veiled any such appearance, even if 

 it were present. The cirrus clouds, however, were 

 arranged in streaks, seemingly radiating from the 

 north-west. I have noticed such an arrangement of 

 the cirrus clouds in former magnetic storms. 



A. L. CORTIE, S.J. 



Stonyhurst College Observatory, August 14. 



Wild Birds and Distasteful Insect Larvae. 



I HAVE read the letter of the Hon. H. Onslow 

 (Nature, August) 14, p. 464) with much interest, and 

 I shall certainly continue the investigation as soon 

 as opportunity offers. 



I regret that I must disagree with the attitude 

 adopted by Mr. Edward R. Speyer (Nature, August 7, 

 p. 445). In my letter on the subject I had no 

 intention of refuting the observations of Prof. 

 Poulton or of any other observer. I simply recorded 

 what I had seen, and suggested that parasitism 

 of the larvae might afford an explanation, but Mr. 

 Speyer introduces a condition which certainly did not 

 exist in the spring of 1918. He writes: — "In times 

 of stress birds have long been known to subsist upon 

 insects with highly distasteful qualities " ; and again : 

 "The currant-moth larva . . . has merely been eaten 

 by the thrush, and possibly by the other birds men- 

 tioned . . . when the stress of having to feed a family 

 has made such a practice a necessity." 



At the time my observations were made there was 

 no necessity for the birds to feed upon these larvae. 

 Insect larvae of all kinds were seldom, if ever, more 

 numerous. There were an abundant supply and a 

 great variety. The currant-moth larvae were probably 

 the most numerous, and with such an ample supply 

 of food the birds fed upon them. 



Walter E. Colli nge. 



The University, St. Andrews. 



