536 



NA TURE 



[April T, 1887 



Their surface was marked with rid'^es (6), and they had a central 

 hollow divided by diaphra,:^nis." 



I will examine these statements seriatim. 



(i) The author appears to have been strangely ignorant of 

 Sir William Dawson's magnificent discoveries of Calamites and 

 other Carboniferous plants in the Devonian strata of North 

 America, announced in his Report on the subject in 1871. 



(2) In 1S74 I published in the Philosophical Transactions the 

 detailed structure of extremsly beautiful examples of Calamo- 

 stachys BinHeynna, and, since then, Prof. Weiss, of Berlin, 

 has figured equally fine examples of Calamostachys Liidwigi. In 

 the Philosophical Transactions for 1881 I further showed that 

 this genus comprehended both homosporous and heterosporous 

 forms. At the same time Calamostachys is not the fruit of 

 Calamites. 



(4) Both Sir William Dawson and Prof. Weiss have shown 

 that the slender twigs of Calamites were abundantly supplied 

 with verticils of linear leaves. 



(5) This statement is true with an important limitation, which 

 Dr. Goebel ignores ; or, as a follower of M. Renault, he more 

 probably rejects. Whilst the type of Calamitean organisation 

 is unquestionably Equisetiform, their arborescent stems and 

 branches contained an enormous xylem or woody cylinder, 

 developed exogenously, which made them differ very widely from 

 their degenerate living representatives. 



(6) This is a repetition of the old fallacy, which regarded the 

 vertical groovings of the surfaces of the inorganic ca-ts of the 

 fistular medullary cavity as belonging to the cortical surface. 

 We have now numerous sections of the Calamitean cortex, no 

 one of which exhibits the slightest trace of vertical flutings ; 

 they are all smooth. 



On p. 281, speaking of heterosporous Lycopodiaceje, the 

 author accepts M. Renault's old conclusions that in Lepidoden- 

 dron "there is no certain indication of secondary growth in 

 thickness." "The connection of fossil stems capable of great 

 increase in thickness, such as the Sigillarieae and Calamodendron 

 is at present questioned." These facts are no longer capable of 

 being justly questioned. The structure of Lepidodcndroii Sela- 

 girtoides alone suffices to settle the matter so far as that genus is 

 concerned ; to say nothing of the many other species that demon- 

 strate the same fact. M. Grand'Eury himself, long one of the 

 most influential questioners, has now recognised that the genus 

 Arthropitus only represents the thick woody zone of a true 

 Calamite. Prof. Stur, of Vienna, long ago demonstrated in an 

 unanswerable manner the almost absolute identity of Calamites 

 and Calamodendron ; and M. Renault himself, as I have already 

 observed, has still more recently been compelled by the discovery 

 of a Sigillarian fructification by M. Zeiller to alter his view 

 respecting the Sigillariae. He no longer insists that these cannot 

 be Cvyptogams because their stems grow exogenously, but now 

 hands over to his opponents, who have so long contended for the 

 Lycopodiaceous affinities of this Sigillarian genus, all the vertically 

 fluted examples of it. 



Whilst deeming it desirable that his readers should be put in 

 possession of the other side of the question to which he refers, 

 it is only fair to Dr. Goebel to say he is himself aware that those 

 questions are dealt with in a one-sided manner. In a footnote 

 on p. 272 of the English translation the author says : — "The 

 short description given in the text from Renault may serve at 

 least to draw attention to these interesting types, in which there 

 is much that is yet uncertain. We cannot enter here into dis- 

 puted or doubtful points." At the same time it is to be lamented 

 that the leading botanists of the world cannot give us palaeonto- 

 logists- more of that valuable aid which their special studies would 

 so well enable them to do. I do not yet despair of enlisting 

 some of the Slrasburgers, de Barys, Goebels, and Van Tieghems 

 in this honourable service. W. C. Willi.\mson 



Owens College 



A Sparrow chasing Two Pigeons 



On Sunday, I asked three men what they were observing, 

 when they pointed out a sparrow chasing two pigeons. 



The pigeons were evidently greatly alarmed at their pugnacious 

 attendant, who took occasional pecks at them when flying under- 

 neath, and whenever possible. The sparrow lost ground when 

 the others made their more rapid doubling, but soon came up 

 with them a^ain, and renewed its attack. 



What was the original quarrel of course we do not know, 

 but the persistency of the sparrow's attack greatly amused us. 



Have any of your readers observed anything like this ? or is 

 there any record of the like ? E. A. C. 



Luton, Chatham, March 14 



Top-shaped Hailstones 



I DREW attention to hailstones possessing the above form in 

 Science Gossip of December 1884. These pellets, which fell 

 in my garden at Polmont, Stirlingshire, on the morning of 

 May 6, 1884, were about one-fourth of an inch in length, and 

 nearly three-sixteenths of an inch across. I did not see any 

 horizontal stratification as observed by your correspondent 

 Mr. Middlemiss, but found that each transverse section, when 

 examined by a good lens, exhibited a fairly well-marked internal 

 radiated fibrous structure, somewhat similar to that shown in 

 sections of the mineral wavellite. Below are two (transverse 



. — Transverse section (near Fig. 2.— Longitudinal 5 



base of cone) X 2. 



IX,}. 



and longitudinal) diagrammatic sections of the Polmont hail- 

 stones. 



Since then, however, I have found top-shaped hailstones com- 



FlG. 3. — Longitudinal section. Fig. 4. — Transverse section of Fig. 3. 



posed of fibres radiating from the summit of the pyramid as shown 

 in Fig. 3. .\lexander Johnstone 



Edinburgh University 



A Peculiar Radiation of Light 



At 10.30 p.m. this evening, my attention was called to a 

 peculiar radiation of light in the eastern sky. The centre of 

 radiation was due east, and the bars on the right-hand side were 

 increased in brilliancy by light evidently arising from the moon, 

 which was not visible, but concealed by cloud. The extent of 

 these rays was from horizon to zenith ; the rays being of un- 

 equal size, but of a pale gray colour, slightly iridescent. 



The east wind was blowing smartly at the time, and I should 

 like to be informed whether this strangely beautiful appearance 

 in the sky was caused by the radiation of light from a rising 

 moon on thin cloud-, or was it the effect of a strong current of 

 wind from a given point ? 



By II p.m. the moonlight was full ; the moon still to the right 

 of the axis of the rays, and the rays nearly dispersed. 



Falmouth, March 12 Robert D. Gibney 



THE CHEMICAL SOCIETY'S ANNIVERSARY 

 MEETING 



THE anniversary meeting of the Chemical Society was 

 held on Wednesday, March 30. We give some 

 extracts from the address of the President, Dr. Hugo 

 Miiller, on the recent progress of chemical science : — 



As we contemplate this ceaseless activity in chemical 

 research now manifested all over the world, and which 

 from year to year is continually on the increase, we are 

 nevertheless bound to recognise the fact that vast as the 

 work thus accumulated may appear, there remains still 

 much to be accomplished. The more the field is worked 

 the richer will be the harvest. 



Overwhelmed by the quantity of material, especially in 

 the direction of the production of new compounds, hasty 

 critics were wont to denounce such work as superfluous, 

 but it is now generally recognised that we must still 

 continue with the patient and careful elaboration of the 

 substructure of facts before we can with advantage pro- 

 ceed with the longed-for rearing of the edifice of a 

 comprehensive scientific generalisation, that is to say, 

 of ideal chemistry. 



The infinite complexity which inquiry reveals in every 



