454 



NA TURE 



[September 9, 1897 



Flora of the Malayan Peninsula," by Dr. George King, F.R.S. 

 The publication of these very valuable contributions to botanical 

 science was commenced more than seven years ago, but pres- 

 sure of other work has prevented Dr. King from making as 

 rapid progress as he desired. In the present part the account 

 of the Calyciflorce is begun, and it is hoped that one more con- 

 tribution similar in size to that just published will suffice to com- 

 plete the Calyciflorre, and bring the whole series about half-way 

 towards completion. 



During the Norwegian North-Atlantic Expedition (1876-78), 

 Prof. G. O. Sars collected from the surface a quantity of plank- 

 ton containing many algae, especially Diatoms. He described 

 the most characteristic forms, and early last year handed over 

 the samples for more detailed study to H. H. Gran, whose 

 description of the material has now been published in Memoir 

 xxiv. of the "General Report of the Norwegian North- Atlantic 

 Expedition " (Christiania : Grondahl and Sons), printed in both 

 Norse and English. The study of the material shows that the 

 water of the Atlantic is especially characterised by Chwtoceros 

 decipiens, atlanticum, boreale and Briqkiwelln, and by several 

 Rhizosolenia species. The water of the Polar Sea during 

 summer is characterised by Chcetoceros furcellaiuvi, Fragilaria 

 oceanica, and Thallassiosira species. From the contents of the 

 samples, however, no decided boundary could be drawn, either 

 because the ocean currents mix to a certain extent with one 

 another, or because the Diatomacese have the power of rising or 

 sinking from one stratum of water to another, independently of 

 the currents. Mr. Gran states that he has obtained evidence 

 which clearly points to the occurrence of the latter possibility. 



The following are among noteworthy papers and other 

 publications which have been received during the past few 

 days : — The letters exchanged between the two mathematicians 

 Jakob Steiner and Ludwig Schlaffi from the year 1848 to 1856 

 are printed in the Mittheihmgen der Nahirforschenden Gesell- 

 ^chaft in Bern (1896), edited by Prof. J. H. Graf.— Mr. Bernard 

 Quaritch has just issued two catalogues (Nos. 170, 172) of 

 scientific books, and Transactions of learned societies, offered 

 for sale by him. We notice in the list a set of Challenger 

 Expedition Reports for sale for 67/. 105. Scientific book-buyers 

 and librarians should certainly see Mr. Quaritch's catalogues.— 

 Part v. of " Fresenins' Quantitative Analysis " (vol ii. ), translated 

 by Mr. Chas. E. Groves, F.R.S., has just been published by 

 Messrs. J. and A. Churchill. 



The additions to the Zoological Society's Gardens during the 

 past week include a Huanaco {Lama huanacos, ? ) from Bolivia, 



presented by Mr. W. J. Huxley ; a Mouse {Phyllotis 



griseojlavus), two Chimachima W\\v&.^o%{Milvago chimachima), 

 three Pileated Song Sparrows {Zonotrichia pileata), three Yel- 

 lowish Finches {Sycalis hiteola), two Bay Cow Birds {Molothrus 

 bodins), a Yellow Troupial {Xahthoso?nus Jlavus) from Argentina, 

 three West African Love Birds (Agapornis pullaria) from West 

 Africa, presented by Mr. E. A. Fitzgerald ; a Malabar Squirrel 

 (Sciur us maxttjuis) ixora India, presented by Mr. J. E. Summers; 

 two Rough-legged Buzzards (Archibuteo lagopus), European, 

 presented by Mr. H. W. Feilden ; a European Tortoise {Etnys 

 orbicularis) European, presented by Mr. Duncan Dickens ; 

 eleven Green Lizards {Lacerta viridis), two Sand Lizards 

 {Lacerta agilis), a Wall Lizard {Lacerta muralis), European, 

 presented by Mr, C. W. Tytheridge ; a Crested Porcupine 

 {Hystrix cristata), three White Storks {Ciconia alba), a Greater 

 Black-backed Gull (Larus marinus), a Herring Gull {Larus 

 argentatus), a Common Night Heron {Nycticorax griseus), two 

 Buzzards {Buteo vulgaris), European, two Ypecaha Rails 

 {Aramides ypecaha) from South America, deposited ; a Barbary 

 Wild Sheep ( Ovis tragelaphus), born in the Gardens. 



NO. 1454, VOL. 56] 



OUR ASTRONOMICAL COLUMN. 



Dedication of the Yerkes Observatory. — The formal 

 dedication of the Yerkes Observatory will take place on 

 October 21-22, and not on October i, as previously announced. 

 In connection with the dedication, a series of conferences on 

 astronomical and astrophysical subjects will be held at the 

 observatory on October 18, 19, 20, and 21. The provisional 

 programme for these meetings is published in the August number 

 of the Astrophysical Journal. 



Southern Double Stars. — Profs. W. H. Pickering and 

 S. I. Bailey have taken advantage of the steady air of Arequipa, 

 and the consequent good definition, to search for close double 

 stars m the southern skies. All the stars of the sixth magnitude 

 and brighter, south of declination - 30°, have been examined 

 for close companions, with the 13-inch Boyden telescope. 

 Nearly one hundred and fifty stars were thus found to have 

 companions at distances not exceeding thirty seconds of arc, 

 not counting stars already announced as double in the cata- 

 logues of Herschel and Russell. The numbers of these stars in 

 the Argentine General Catalogue are recorded in Harvard 

 College Observatory Circular, No. 18. 



Variable Stars in Clusters. — The important fact that a 

 large number of individual stars in certain globular star clusters 

 are variable, sometimes to the extent of two magnitudes or 

 more, was announced in Harvard College Observatory Circular 

 (No. 2) in November 1895 (see Nature, vol. liii. p. 91), and 

 was again referred to in May 1896 (Nature, vol. liv. p. 108). 

 A Circular (No. 18) just received from the observatory, 

 announces that Prof. S. I. Bailey has found many more of 

 these, bringing their total number up to 310. The greatest 

 number of variables occur in the cluster No. 5272 in the New 

 General Catalogue (Messier 3), as many as 113 stars in this 

 cluster having been found to fluctuate in light. In N.G.C. 5904 

 (Messier 5), 63 stars have been proved to be variable, and in 

 N.G.C. 5139 (« Centauri) 60 stars appear to undergo light- 

 changes. It is remarkable that while in the cluster Messier 3 

 about one-ninth of the stars are variable, in other clusters, 

 for instance the great cluster in Hercules (N.G.C. 6205), not a 

 single variable was found out of nearly two thousand stars 

 examined. 



The Magnitudes of the Asteroids. — An interesting 

 history of the asteroids and the questions to which they give 

 rise, is given by Herr G. Huber in the Mittheilungen der 

 Nattii-forschenden Gesellschaft in Bern for the year 1896. The 

 mean magnitude at opposition of the first four hundred minor 

 planets are tabulated in groups of fifty as follows, the column 

 marked Mag. 8 including asteroids of magnitudes 8 to 8*9, while 

 the column marked Mag. 9 includes all from magnitude 9 to 

 mag. 9 '9, and so on for other magnitudes. 



The table shows clearly that the asteroids discovered in recent 

 years, namely those from No. 200 to No. 400, are mainly of the 

 twelfth magnitude, or even fainter than that. 



A New Nebula Photograph. — A brilliant picture of the 

 nebula Herschel V 15 Cygni (No. 6992 in the New General 

 Catalogue), reproduced from a photograph obtained by Dr. Isaac 

 Roberts, F.R.S., with an exposure of 2h. 55m., appears in the 

 September number of Knowledge. The nebula is a wave-like 

 brush of light, measuring about eighty minutes of arc in length. 



