5i8 



NA TURE 



[March 30, 1893 



Messrs. J. B. BAiLLifeKE et Fils, Paris, have issued the 

 first volume of a worlt entitled " i:iements de Paleontologie," 

 by Felix Bernard. No fewer than 266 figures appear in the 

 text. The same publishers have issued in their " Bibliotheque 

 Scientifique Contemporaine " a book on " Les Lichens," by 

 A. Acloque. He deals with the anatomy, physiology, and 

 morphology of the lichenic organism. 



Messrs. George Bell and Sons have issued the second 

 volume of Mr. George Massee's " British Fungus-Flora," a 

 classified text-book of mycology. The work will be completed 

 in three volumes. 



Prof. B. Koto has contributed to the Journal of the College 

 of Science, Imperial University, Japan (vol. v. pari 3) a learned 

 paper on the Archaean formation of the Abukuma Plateau. 

 The paper is illustrated with several plates. 



Messrs. Bailli^re, Tindall, and Cox have published a 

 second edition of Veterinary Captain F. Smith's " Manual of 

 Veterinary Hygiene." The only important alterations in the 

 book are those in the chapter on ventilation. 



A valuable "Catalogue of American Localities of 

 Minerals," by Prof. E. S. Dana, has been reprinted by Messrs. 

 John Wiley and Sons from the sixth edition of Dana's " System 

 of Mineralogy." 



The Wagner Free Institute of Science proposes to issue a 

 reprint of T. A. Conrad's monograph of " The Medial Tertiary 

 Fossils of the United States," if subscriptions for 150 copies can 

 be obtained. The original plates would be reproduced by a 

 process of photo-engraving, and a brief introductory chapter 

 and a table would show the present state of the nomenclature of 

 the species contained in the work. 



Starting with an observation by Herz, that the cathode 

 rays causing phosphorescence can pass through thin metallic 

 plates, Herr Lenard has recently made some interesting experi- 

 ments (described to the Berlin Academy) with an arrangement 

 in which the rays from a small aluminium disc (as cathode) were 

 projected on a thin aluminium " window " (0*003 ™tn- thick), 

 in a thicker metal plate at the opposite end of the tube. The 

 lateral anode was connected to earth, and a large inductorium 

 was discharged through the tube. These cathode rays passed 

 through the window, and made the air faintly luminous, with 

 bluish light, brightest at the surface of the window. There was 

 a strong smell of ozone. Phosphorescent bodies, bodies brought 

 near the window, glowed, having the same colour as in vacuo. 

 At about 2*4 inches distance the phenomenon ceased ; it also 

 ceased when the cathode rays were deflected with a magnet, or 

 when a screen of sufficient thickness was interposed. But 

 owing to diffuse spread of the rays the phosphorescent action 

 extended into the shadow of the opaque screen. This field of 

 observation beyond the window could be enclosed and evacuated, 

 and the higher the vacuum, the greater was the distance at which 

 phosphorescence took place, and the sharper and brighter were 

 the rays — indicating (in the author's opinion) that these cathode- 

 rays are a process in the ether. Herr Lenard tried other gases 

 besides air, and found varying penetration by the rays. When 

 coal gas was let pass between the window and the phosphorescent 

 body the latter brightened. When the fieLl of observation 

 (enclosed) was filled with hydrogen at atmospheric pressure, the 

 phosphorescence extended thrice as far as in air at the same 

 pressure (viz. to about 8 inches). Oxygen and carbonic acid 

 were less penetrable than air. "One may say that hydrogen 

 molecules cause less turbidity in the ether than those of oxygen, 

 and the latter less than those of carbonic acid." 

 NO. 122 2, VOL. 47] 



Notes from the Marine Biological Station, Plymouth :— 

 Last week's |captures include the Nemertine Linens marimiy 

 (=Jongissifnus) and the long-spined sea-urchin [Echinus acutus). 

 In the floating fauna the principal change has consisted in a 

 great reduction in the numbers of Echinoderm larvae and in the 

 gradual disappearance of Azireh'a-ephyix, as well as in the ap- 

 pearance of numbers of Arachnaclis (larva of the Actinian Cere- 

 anthus), of the Leptomedusa Irene pellucida (Claus, non 

 Haeckel), and of a few Porcellana larvae. In addition to these, 

 small Obelia medusae and the Appendicularian Oikopleura dioica 

 have been abundant, and young Ctenophores and Planarians 

 have been occasionally present. The Hydroid Eudendrium 

 ramosum, the Nemertine Amphiporus pulcher, and the crab 

 Portunus arcuatus are now breeding. 



The additions to the Zoological Society's Gardens during the 

 past week include a Mozambique Monkey ( Cercopithecus pygery- 

 thus, 9 ) from Zanzibar, presented by Mr. C. E. Reynolds ; a 

 Macaque Monkey {Macacus cynoinolgus) from India, presented 

 by Mr. J. W. Jones ; a Coypu {Myopotamus coypus) from South 

 America, presented by Mr. Arthur Hunt ; a double-banded 

 Sand Grouse {Plerocles bicinctus) from Senegal, presented by 

 Mr. H. H. Sharland, F.Z.S. ; three Common Peafowls (/'az/c? 

 cristattis, i i ^) from India, presented by Mr. W. Murphy 



Grimshawe; ten Fishes [Giradinus guppyi)i'CQxa Trinidad, 



presented by the Marquis of Hamilton ; a Hawfinch {Cocco- 

 thraustes vulgaris), four Bramblings {Fringilla montifringilla) 

 British, purchased ; a Hog Deer {Cervus porcinus) born in the 

 Gardens. 



OUR ASTRONOMICAL COLUMN. 



Comet Holmes (1892 III.). — Prof. Keeler, in speaking of 

 the hypothesis that this comet has been produced by a collision 

 between two asteroids, says that the character of the spectrum 

 has little to support this view. He accounts for the brightening 

 on January 16 by supposing that an increase in the number of 

 reflecting particles in the space surrounding the comet took place, 

 i.e. by an increase of density, which might result from a con- 

 traction following the previously observed expansion of the 

 comet, or, which is more in accordance with the observations, 

 from fresh emanations from the nucleus {Astronomy and Astro- 

 physics for March). 



^4/rt»/£>5 of the same hypothesis, Prof. C. A. Young queries 

 whether, if the asteroids were formed by a series of " explosions," 

 breaking up first the original planet and afterwards the pieces 

 from it, this might not be an event of that sort — an eruption 

 from an asteroid. We continue the ephemeris for the week : — 



12//. Paris Mean Time. 



WoLSiNGHAM OBSERVATORY, Circular No. 34. — The star 

 Es-Birm 180 6h. 15 "Sm. + 47° 43' was found to be io"5 March 

 20 and is variable. On March 18, a red HI. Type star, 8*5 

 mag. was seen at 3h. 23"5m. -f 58'' 11' and may be variable. 

 Not in D.M. Places for 1900. 



Jupiter and his Satellites. — Writing from Arequipa, 

 Peru, Prof. Pickering communicates to Astronomy and Astro- 

 physics for March an account of the very valuable and important 

 observations that he made during the past favourable opposi- 

 tion of the planet Jupiter. A minute study of the planet's 

 surface gave him the impression that his surface consists of a 

 "uniform white mass of cloud," over which is stretched a 

 gauzy and thin veil "of a brown material, resembling in struc- 



