Oct. 17, 1889] 



NA TURE 



611 



massive, a character which is well suited to growth in subaerial 

 and dry situations ; while in the former the whole structure is 

 relatively delicate, and less complex, and suited rather to a sub- 

 aquatic habitat. A parallel prof;ression from the simpler to the 

 more complex is to be traced also in the prolhallus or oophyte 

 of these plants, and the general conclusion is diawn from these 

 observations that the series of the Filiciiies: illustrates — perhaps 

 more clearly than any other phylum— the rise of a race of plants 

 from the arjuatic to the subaerial habit. Nevertheless they still 

 retain in the mode of fertilization the trace of the aquatic habit, 

 which is only lost in the higher Phanerogamic plants, where the 

 pollen-tube renders unnecessary the presence of fluid water at the 

 moment of fertilization. 



The paper by Prof Hartog, on the structure o^ Saprolegnia, 

 contained an account of the structure of the nucleus and 

 of its division, and also of some remarkable facts concerning 

 fertilization ; careful observation showed that nothing whatever 

 passed from the antheridium into the oosphere or the oospor- 

 angium during fertilization. 



In the paper entitled "Contributions to our Knowledge of the 

 Fresh-water Oligochteta," by Mr. F. E. Beddard, the most 

 important new point was the description of the sexual organs 

 of Dero, which have not yet been described ; they were stated 

 to agree entirely with those of Nais, except that there were no 

 genital setre. 



Mr. Robert Irvine and Dr. G. Sims Woodhead, in their 

 paper on the secretion of carbonate of lime by animals, 

 stated that hens supplied with any salt of lime produce normal 

 egg-shells composed of carbonate of lime. They cannot make 

 shells from magnesium or strontium carbonate. Crustacea, such 

 as crabs, cannot assimilate sulphate of lime from the sea-water 

 to form their exo-skeleton. They can form their shells from 

 calcium chloride. In the egg-shell, the organic and inorganic 

 material are both secieted by cells separated from the epithelial 

 cells. In the crab-shell, the organic material (chitin) remains 

 attached to the epithelial cells, and in this the lime salts are 

 deposited, probably by a process of dialysis, while in the case of 

 bone, the cells are not epithelial in character, the matrix, 

 though separate, is closely associated with the cells, especially 

 during its formation, and the lime is deposited in the matrix, 

 apparently by a process of dialysis. Phosphoric acid, combined 

 with alkalies and alkaline earths, acts as the carrier of the lime 

 salt to the secreting cells. While in the blood, the lime salt is 

 as a phosphate, it maybe thrown out mostly as carbonate on 

 meeting nascent carbonic acid at the secreting cells. Lime 

 salts, of whatever form, are deposited only in vitally inactive 

 tissue, such as bone matrix, chiiin, or tissues that have under- 

 gone degeneration. Although the tissue be dead, deposition 

 may go on. Carbonate of lime may be formed in sea-water as 

 follows: the carbonate of ammonia produced by the decomposi- 

 tion of the effete products of animals, urea, &c., decomposes a 

 portion of the sulphate of lime in the sea-water with the forma- 

 tion of carbonate of lime equivalent in amount to the carbonate 

 of ammonia thus formed. 



Sir John Lubbock read a paper on the shape of the oak-leaf 

 and the leaves of the Guelder roses. The leaf of the evergreen 

 oak is small in comparison with that of the English oak, and its 

 margin is entire. During winter the leaf is protected by scales, 

 which are not proportionately larger in the English oak ; hence 

 the leaf must be more folded in the bud, and the peculiar shape 

 of the leaf may be shown by models to be due to the shortness 

 of the bud in comparison with the length of the leaf ; moreover, 

 the two sides of the leaf are differently curved, hence the asym- 

 metry. With regard to the Guelder roses, there are two species 

 in this country which have very dissimilar leaves : in one form 

 they are oval and very hairy when young ; in the other they are 

 trilobate, smooth, and furnished with stipules. In the former 

 species the hairy covering protects the young leaves, but in the 

 latter the outer leaves become tough and leathery, and encircle 

 and protect the younger leaves ; this brings about a close pack- 

 ing of the young leaves, which are folded so as to be stowed 

 •away in a small space ; hence their trifid form. The presence of 

 stipules is always associated with a lobed form of the leaf, and 

 they apparently assume their thread-like form to fill up a space 

 which would otherwise be left empty in the bud. 



The object of the paper on the placentation of the dugong, 

 by Sir W. Turner, was to put on record the fact that the 

 placenta of the dugong is zonary and «tf«-deciduate ; it differs, 

 therefore, in the latter character from the elephant, and in the 

 former from its near ally the manatee. 



i UNI VERS I TY AND ED UCA TIONA L 



I INTELLIGENCE. 



\ Oxford. — The summary statement of lectures deliverecJ 

 I during the past year shows that about ninety-five courses of lec- 

 j tures have been given in the subjects of the Faculty of Natural 

 I Science. 



We may i:ote the folJowirg among the lectures anrounced for 

 this term : — 



Prof. Sylvester will lecture on the resolution in integers 

 I of s) stems of linear equations vith rational cceflFcienls, and" 

 will reproduce an unpublished course of lectures given at 

 King's College in 1869, on the relation of the theory of com- 

 pound partitions of numbers to certain geometrical theories. 

 Prof. Pritchard will lecture on planetary theory and on the 

 Constellations. 



Prof. Clifion, magnetism ; Mr. Selby, the mathematical theorjr 

 of electrostatics and magnetism.' 

 Prof. Odling, diacidic olefire acids. 



Prof. Green, straiigraphical geology and physical geology ;: 

 Mr. Badger, palaeontology. 



Prof. Burdon Sanderson is unfortunately prevented from lec- 

 turing by serious illness, and Mr. Gotch and Dr. Haldane wilP 

 lecture for him. 



Dr. Tylor lectures on the development of religions, and Mr, 

 Mackinder on the physical geography of the British Islands. 



In the Medical P'aculty, Mr. Thomson lectures on osteologv^ 

 Dr. Collier on the methods of diagnosing disease of the hearty 

 and Mr. Morgan on clinical surgery. 



Scholarships and Exhibitions in Natural Science are offeree? 

 for competition before Christmas by Balliol, Christ Church, and 

 Trinity, and by Keble College. 



Cambridge— The Vice-Chancellor (Dr. Searle), in laying 

 down his office, was able to relate that the ex<cutors of Mr. 

 Newall had agreed to the conditions proposed to be made by 

 the Senate as to the great telescope to be given to the Univer- 

 sity. The expense of transit, re-erection, and permanent work 

 in promotion of stellar physics will be considerable. 



The election of Mr. Jenkmson as Librarian gives the Univer- 

 sity an official who, in addition to his well-known classical and 

 literary accomplishments, has no mean scientific qualifications. 

 He was for some time Curator in Zoology, and is a member of 

 the Botanic Gardens Syndicate and of the Council of the Cam- 

 bridge Antiquarian Society. Men of science cannot regret Mr. 

 Clark's retirement from the contest, for he literally could not be- 

 spared from the Museums, though otherwise highly quahfitd for 

 the Librarianship. 



There are very few new features in the science lectures this- 

 term. The list is, if anything, slightly longer, srd would filltwe> 

 of our pages; but there is nclhirg in it calling for specia> 

 comment. 



SCIENTIFIC SERIALS. 



The American Meteorological yonrnal for September con- 

 tains (i) an article by Prof. II. A. Hazen on cloud formation. 

 The author considers that theories of storm generation and clouet 

 formation are unsatisfactory. He has made a number of ex- 

 periments, both with dry and damp air, on the formation of 

 cloud by the cooling produced by exhaustion, the result being 

 that he finds the amount of the latter to be only about one-fourtb 

 of what theory would indicate. The results obtained with dry 

 and moist air were almost exactly the same. (2) State tornaelo- 

 charts for Alabama and Ohio, by Lieutenant Finley. (3) An 

 article on the verification of weather forecasts, by H. Helm 

 Clayton. He points out that all the methods adapted admit of 

 considerable latitude in interpreting phenomena, so that the same 

 forecasts, when verified by different persons, may differ widely as 

 to the percentage of success, and he suggests an arrangement 

 which may be applied to areas as well as to single stations, and 

 which, at the same time, might be useful in .studying the relative 

 frequency of each phenomenon. (4) The distribuiion of wind 

 velocities in the Ut,ited States, by iJr. F. Waldo, deduced fron-» 

 the record< of the self recording anemometers at the stations of 

 the Signal Service. In this article, which is unfinished, the author 

 deals exclusively with the values of the constar.ts derived from 

 various anemometrical experiments in Germany and Russia. 



The Mcteorologische Zeitschrift for September 1889 contains, 

 a discussion, by Dr. J. Hann, of Parts iv. and v. of '' Contribu- 

 tions to cur Knowledge of the Meteorology of the Arctic 



