jVA ture 



[NOVEMHEK 14, 1901 



while in a third, Dr. Bashford Dean adduces evidence to prove 

 the existence of vestiges of an original holoblastic cleavage in 

 the egg of the Japanese representative of the I'ort JacUson 

 shark. This discovery is of the highest morphological import- 

 ance, sharks' eggs having been hitherto regarded as typically 

 meroblastic. " No one, I fancy," writes the author, "would 

 have been bold enough to have prophesied that the wide 

 difference between the typically meroblastic egg of the .shark 

 and the holoblastic egg of such a teleostome as a sturgeon might 

 come to be bridged over within the limits, not of fossil sharks, 

 but of recent sharks themselves." 



Thk singular bulbiform seeds of certain Amaryllidca; — espe- 

 cially species of Amaryllis and Crinum — are the subject of an 

 interesting paper by Dr. A. B. Uendle in the November number 

 of \\\e Journal of Botany. These seeds are of three kinds : — 

 (l) True seeds developed from a normal ovule, the outer integu- 

 ment of which becomes thick and fleshy after fertilisation, and 

 forms the substance of the bulbiform mass ; (2) true seeds 

 developed from a naked ovule, the fleshy substance being 

 derived entirely from the endosperm, which develops chlorophyll 

 in its outer layers and continues to grow for some time ; (3) a 

 vegetative growth replacing the seed ; a normal ovule is pro- 

 duced, but a viviparous growth of an adventitious shoot and 

 root takes place at the base, and a bulbil is formed, the ovule 

 integuments forming the outer coats. 



Dr. Friedrich Berwerth has communicated to the Vienna 

 Academy of Sciences a paper on soundings from the eastern 

 Mediterranean. In regard to the distribution of calcareous mud, it 

 is found that two principal zones exist, one to the north of the Nile 

 delta, which extends along the Syrian coast and contains but little 

 carbonate of lime (5 to 15 per cent.), while the other, consisting 

 of the remainder of the eastern Mediterranean, is largely cal- 

 careous, the proportion of chalky matter being on an average 

 60 per cent., with variations of 20 per cent, above and below 

 this average. The relation between the proportion of calcareous 

 matter and the depth appears to be at variance with what would 

 be expected from Murray's theory. The sedimentary matter 

 consists, in general, of (i) calcareous organic remains (mollu.sca 

 and foraminifera), (2) fragments of siliceous matter of organic 

 origin, including sponges and radiolaria, (3) fragments of minerals 

 and rocks, (4) a precipitate, partly calcareous, partly argillaceous, 

 showing little microscopic structure, wliich constitutes the main 

 part of the mud. 



A sotTND and practical knowledge of " The Cyanide Process 

 of Gold Extraction " can be obtained from the volume on that 

 subject by Prof. James Park, published by Messrs. Charles 

 Grifiin and Co. The first English edition was favourably 

 noticed in these columns last year (vol. Ixii. p. 148), and the 

 second has now appeared. The whole volume has undergone 

 revision, and the new matter includes a detailed description of 

 well-designed slime and sulphide plants now in use in the great 

 mining centres of the world. — Another of Messrs. Griffin's 

 technical handbooks which has reached a second edition is 

 " Practical Coal Mining," by Mr. George L. Kerr, the first 

 edition of which was reviewed in Nature of February 28 

 (vol. Ixiii. p. 417). 



Low-TEMi'ERATfRE research at the Royal Institution during 

 the past seven years has been assisted by the Uodgkins Trust 

 Fund -a sum of 100,000 dollars left by the late Mr. T. G. 

 Hodgkins as a source of income to be employed in the "inves- 

 tigation of the relations and co-relations existing between man 

 and his Cieauii." To show what has been done towards this 

 end. Miss Agnes M. Gierke has prepared for the Hodgkins Fund 

 a popular essay on Prof. Dewar's work at the Institution from 

 1893 '° 1900. The essay traces the course of his researches in 

 the physics and cliemistry of low temperature, and contains, in 

 NO. 1672, VOL. 65] 



addition, three illustrations showing the lecture table of the 

 Royal Institution upon the ocoision of the centenary com- 

 memoration lecture on liijuid hydrogen, and the elaborate re- 

 frigerating machinery and liquid hydrogen apparatus used by 

 Prof. Dewar. 



The current number of the Bcrichle contains a jiaper, by A. 

 Hantzsch and A. lIoU, on siilphimide. This substance was 

 first obtained by W. Traube from the products of the action 

 of ammonia upon sulphuryl chloride, and the formula SOoNH 

 was attributed to it, from the analyses of its salts. In the 

 present paper the authors have been successful in obtaining 

 sulphimide in the solid form, and have found by molecular 

 weight determinations that it resembles cyanuric acid in being 

 trimolecular (SO.iNU).,. They have also succeeded in isolating 

 the methyl ester of this substance, and have found that this is 

 also trimolecular. It is pointed out that the analogy between 

 the nitrogen derivatives of carbonic acid and sulphuric acid is 

 much closer than has hitherto been supposed. 



Jiulletin No. 186 of the U.S. (Geological Survey contains an 

 interesting study of pyrites and marcasite, by Dr. II. N. Stokes, 

 and describes a method for the quantitative determination of 

 these minerals when in mixture. The method depends upon 

 the fact that when either mineral is boiled with an excess of a 

 solution of ferric salt to complete reduction of the latter the 

 ratio of sulphur oxidised to mineral decomposed is perfectly 

 definite and characteristic of each mineral, provided certain 

 standard and easily controllable conditions are observed. 

 Under these conditions the percentage of sulphur oxidised on 

 pyrites is about 6o'4 per cent, and on marcasite about 18 

 per cent, of the total sulphur. The application of this method 

 has thrown considerable light on several doubtful questions 

 relating to the dimorphous FeS^. It is shown, for example, that 

 density is not a trustworthy means of determining one mineral 

 in presence of the other, that the hypothesis that most natural 

 specimens are mixtures of the two is without foundation, and 

 that there is no evidence of a difference of valency of iron in 

 the two minerals. Specimens crystallising in the regular system 

 are true pyrites, whilst those forming rhombic crystals are true 

 marcasite. 



The additions to the Zoological Society's Gardens during the 

 past week include a White-crowned Mangabey (Cercocebus 

 aethiops) from West Africa, presented by Mr. Fred Gordon ; a 

 Cape Zorilla {Ictonyx sorilla), a Derbian Zonure (Zonurus 

 gigaiiUus) from South Africa, presented by Mr. W. L. Sclater ; 

 a Gazelle (Gazella donas) from Egypt, presented by Mrs. 

 Bensusan ; a Green Monkey {Cercopithecus iallilriihus) from 

 West Africa, presented by Mr. John Booth ; a Bauer's Parra- 

 keet (Plalycerctts zonarii(s) from South Australia, presented by 

 Miss Gillam ; a Lobed Chameleon (Chamaehon pai-vilobtis) 

 from South Africa, presented by the Rev. Duncan Travels ; a 

 Chacma Baboon {Cynoiephalus ponarius) from South Africa, an 

 Alligator Terrapin {Chelydra ierpentina), a I'ennsylvanian 

 Mud Terrapin {Cinoslernuin pennsylvanicum), a Muhlenberg's 

 Terrapin (CUmmys inuhknbergi), six Long-eared Sun Fish 

 {Lcptomis aiiritus) from North America, deposited ; three 

 Australian Wild Ducks (Anas sitperciliosa), bred in the 

 Gardens. 



OUR ASTRONOMICAL COLUMN. ' 



The Leo.nid Meieors. — Arrangements are being made at 



several observatories to record, by eye observations and photo- 



graphy, any Leonid meteors which appear during the epoch of 



the Leonid meteoric shower, November 14-15. 



Nebulosity surrounding Nova Persei. — .-V telegram from 

 the Centralstelle at Kiel announces that from the examination 

 of photographs taken with the Crossley reflector of the Lick 



