s8o 



NATURE 



iFeb. 17, 1S81 



Megnin of Versailles and Dr. Kramer cf Schleusingen, both 

 good authorities on the subject, being at variance thereon. Mr. 

 Michael, believing that detached observations on captured 

 specimens may have produced unreliable results, has himself 

 bred Gamasids, closely followed their changes and grow th, and 

 watched their manners, and thus has arrived at what he on good 

 grounds as-umes to be important results respecting their life- 

 hi-toi-y. He states that the remarkable power of darting each 

 mandible separately with speed and accuracy of ann far in 

 advance of the body, the powerful retractile muscles attached to 

 these mandibles, the organisation of the remainder of the mouth, 

 the extreme swiftness of the creatures, the use of the front legs 

 as tactile organs only, and not for the purpose of locomotion, and 

 the ample supply of tactile hairs in front only, seem to fit the 

 animals for a predatory life, and point to habits similar to those 

 of Cheyktiis and Trombiduim, rather than to those of the true 

 vegetable-feeders, such as the Orbatidte and Tetramachi. He 

 further concludes (i) that Megnin is con-ect in saying Gamasut 

 coleoptratorum and other allied creatures, with the conspicuously- 

 divided dorsal plates, are not species at all, but are immature 

 stages of other species ; (2) that the division of the dorsal plate 

 is, in most cases at all events, a question of degree, and docs not 

 form a sound basis for classification, as applied by Koch, 

 Kramer, and others ; (3) that the dorsal plates do not grow 

 gradually, but alter in size, shape, or development at the ecdysis; 

 (4) that Megnin is right in saying that the characteristic of the 

 so-called G. marginatus is simiily a provision possessed by the 

 females of a large number of species ; (5) that the extei.t of the 

 white margin depends upon the extent to which the abdomen is 

 distended by eijgs ; (6) that Megnin is in error m saying that 

 CoUoptratoriim is the nymph of Crassipes, The nymph of 

 Crassipes does not show any divided dorsal plates which can be 

 seen on the living creature ; (7) that in the species bred there has 

 not been observed any inert stage before the transformations or 

 ecdysis ; (S) that in the same species copulation takes place with 

 the adult female, and not with the immature one, as Megnin 

 contends, and that it is by the vulva, not the anus. — Two papers 

 were read on the coffee-leaf disease (see Science Notes, 

 P- 354)- 



Institution of Civil Engineers, February 8. — Mr. Aber- 

 nethy, F.R.S.E., president, in the chair. — A paper on the 

 temporary works and plant at the Portsmouth Dockyard Exten- 

 sion, by Mr. C. H. Meyer, Assoc. M. Inst. C.E., was read. 



Paris 

 Academy of Sciences, February 7. — M. Wurtz in the 

 chair. — The following papers were read : — On photographs of 

 nebulre, by M. Janssen. It is comp.aratively easy to get a )ihoto- 

 graphic image of the brightest parts of nebula, but very difficult 

 to get complete images which may serve for future comparison. 

 The optical and photographic conditions should be exactly de- 

 fined. M. Janssen suggests taking for criteria images of stars, 

 with plates a little out of focus, so as to give an opaque circle. 

 Five or six of these stellar circles nccompanying the photograph 

 of a nebula would indicate what the couditions had been. — On 

 the thermic formation of pyrogenic carburets, by M. Berthelot. — 

 Some remarks on the characters of chloro-organic gases and 

 vapours, by M. Berthelot. The formation of a white precij^itate 

 in neutral or slightly acid nitrate of silver, traversed by a t-a~euus 

 current, is not a sufficient character of chlorine or hydr. chloric 

 acid. — Examination of materials from some vitrified forts of 

 France ; conclusions, by M. Daubree. The methods of producing 

 these forts seem to have been various. To soften a rod; lilie 

 granite (sometimes used), to fuse its mica, and even, at times, its 

 felspar, in thicknesses of several metres, implies large use of 

 fuel and prolonged skilful effort. The fire was probably apfilied 

 within the walls, and a current of forced air may have been 

 used, besides draught. The makers unconsciously produced some 

 minerals that have only of late been reproduced in the laboraton'. — 

 On the Great Canal de I'Est and the machines set up to ensure its 

 alimentation, by M. Lalanne. This canal (made in consequence 

 of the change of frontier in 1871) runs from near Givet, on the 

 Meuse, by Mezieres, Sedan, Commercy, Toul, &c., to Port--ur 

 Saone (it includes, in a total length of 468 km., 20 km. cf the 

 canal from the Marne to the Rhine). There are two large pumps in 

 the Moselle valley, worked by the water of that river, also steam- 

 pumps at Vacon. Two large reservoirs are projected, one near 

 Paroy, the other at Aouze. — Study of actions of the sun and the 

 moon in some terrestrial phenomena, by M. Bnuqiiet de la Grye. 

 — Observations of Perseids at Toulouse Observatory in 18S0, by 

 M. BaiUaud. 1 172 falling stars were counted on August 9, 10, 



and II ; the maximum was on the loth, between I4h. and I5h. 

 The trajectories were generally very short, and their extremities 

 ■pretty far from the radiant point. The meteors were divisible 

 into two groups. — On mrdes of transformation which preserve 

 lines of curvature, by M. Darboux. — On simultaneous linear 

 differential equations, with rational coefficients, whose solution 

 depends on the quadrature of a given irrational algeVjraic ()roduct, 

 by M. I.'illuer — On a property of the product of k integrals of k 

 linear differential equations, with rational coefficients, the solution 

 of which depends on the quadrature, respectively, of k rational 

 functions of the independent variable, and of a given algebraic 

 irrationality, by the same. — The problem of remainders in two 

 Chinese works, by M. Matthiessen. — On a peculiar phenomenon of 1 

 resonance, by .M. Gripun. A tuning-fork, giving a simple sound, I 

 will set in resonance masses of air which produce a sound comjjrised 

 in the harmonic series of the fork's sound. The form of the mass 

 of air is unimportant. One grave fork set in vibration forks 

 which gave harmonic sounds, but not others, the two forks being 

 connected by very fine copper wire (stretched). — On elliptic double 

 refraction, and the three systems of fringes, by M. CrouUebois. 

 — On a new apparatus for showing the dissociation of amnio- 

 niacal salts, by M. Tommasi. In a glass tube is hung with 

 platinum wire a strip of blue litmus paper that has imbibed a 

 concentrated solution of chlorhydrate of ammonia. On putting 

 this dissocioscope in boiling water, the sal-ammoniac is disso- 

 ciated and the paier turns red ; if then put in cold water the 

 dissociated ammonia combines again with the acid, and the 

 paper turns violet again. — On derivatives of acroleine, by MM. 1 

 Grimaux and Adam. — Action of hydrochloric acid on aldehyde, 1 

 by M. Hauriot. — Inoculation of the dog for glanders, by M. 

 Galtier. The dog may contract the disease (through inoculation) 

 and recover many times ; but its receptivity (comparatively 

 small at first) gradually diminishes, and, there is reison to 

 believe, may be quite effaced. The power of the virus is 

 attenuated by successive cultivations in the dog; this appears in 

 an ass, e.g. inoculated with the later virus of a dog inoculated 

 several times. — Physiology of dyspepsia, by M. Sec. In grave 

 dyspepsia the stomach pump may advantage^ 'Usly be used to 

 clear the stomach of liquids unfavourable to digestion. — On the 

 histology of the pedicellaria and muscles of the sea urchin 

 (Echinus sphis:ra, Forbes), by MM. Geddes and Beddard. — 

 Researches on the development of sterile sporangia, in Isoctes 

 lacustris, by M. Mer. 



Vienna 

 Imperial Academy of Sciences, February 10. — V. Burg in 

 the chair. — C. Heller, on the distribution of the fauna of the 

 high mountains of Tyrol. — R. Maly and Y. Hinseregger, studies 

 on caffeine and theobromine (second paper). — V. Hochstetter, 

 on the Kreutzberg Cave, near Laas, in Carniola, and Ursus 

 spelixus. — K. Puluj (i) on radiant electrode-matter; (z) remarks 

 relating to the priority claimed by Dr. Eugen Goldstein. 



CONTENTS Page 



Island Life, I. By Prof. Arch. Geikie, F.R.S 357 



Alg« .... 359 



Lettei-s to the Editor :— 



"The New Cure for Smoke.'— J. A. C. Hay; Dr. C. W. 



Siemens, F.K.S 360 



On the Spectrum of Carbon— W. M. Watts 361 



" Prehistoric Europe."— Prof. W. Boyd Dawkins, F.R.S. ... 361 



Geological Climates.— Dr. A. WOEIKOFF 363 



Vanable Stars —J. E Gore 362 



The Mode of Fhght of the Albatross.— Howard Sargent . . . 362 



Auroral Phenomena.— Dr. C. M. Ingleby 363 



Oione.-J P 363 



Citania— Rev. R. Burton Leach 363 



The Recent Severe Weather.— F. M. S. ; H. W. C 363 



Buttctfiies in Winter.— Tho.vias W. Shore 364 



ToHN Gould, F R.S 364 



Thh Blackheath Holes. By C. E. De Rance 36s 



Mekcadier's Researches on the Photophone 366 



The John Duncan Fund 367 



The Time of Day in Paris (With Illustrations) 367 



Notes . . . 369 



Our Astronomical Column: — 



The So-called Nova of 1600 37i 



The Min.r Planets m 18S1 37» 



The " Astron mische Nachrichten " 372 



The Cim^t 1880 c (Swift, October 10) 37= 



The Perseids in August, 1880 37= 



Physical NofKs 37' 



Chemical Notfs 373 



Action of an Inter.mittent Beam of Radiant Heat upon 



Gaseous Matter. By Prof. Tyndall, F.R.S 374 



Interesting New Chinoids 377 



University and Educational Intelligence 377 



Scientific Skmals 378 



Societies and Academies 375 



