5o6 



NATURE 



[March 21, 1901 



A description of a palatal portion of a skull from the Loup 

 Fork Miocene deposits of Nebraska, named Atnphicyon aineri- 

 canus, which is undoubtedly to be referred to the European 

 genus. All the Amphicyons of the American Tertiary hitherto 

 described belong to genera quite different and distinct from the 

 typical genus Amphicyon of Europe. — Studies in the Cyperaceae, 

 by T. Holm. Carices [Vigneae] astrostachyae. — A just intona- 

 tion piano, by S. A. Ilageman. A description of a piano 

 mechanism for giving just intonation as opposed to equal tem- 

 perament. — Very on atmospheric radiation, by W. Hallock. 



Annalen der Physik, February. — The electromagnetic rota- 

 tion experiment and unipolar induction, by E. Hagenbach. 

 Lecher has described some results which have led him to regard 

 the usual text-book explanations of many rotation experiments 

 as fallacious. The experimental results here given are in com- 

 plete accordance with the values calculated from the Biot-Savart 

 laws, and, in fact, the fundamental experiment of Lecher fur- 

 nishes an additional proof of their accuracy. — On the law of 

 radiation of black substances, by F. Paschen. A comparison 

 of the theories of Planck and Wein with experiment.— A new 

 determination of the dispersion of fluorspar in the ultra-red, by 

 F. Paschen. — The determination of the selective capacity for 

 reflection of a plane mirror, by F. Paschen. — On the behaviour 

 of liquid dielectrics on the passage of an electric current, by E. 

 V. Schweidler. The results obtained show that the analogy 

 between the behaviour of ionised gases and liquid dielectrics is 

 not an accidental one, but is based upon the phenomena of dis- 

 charge. — On the testing of the magnetic properties of steel, by 

 I. Klemencic. — Determination of the frequency of an alternating 

 current, by R. Wachsmuth. The method described, which is 

 very convenient for vibrations between i and loo per second, 

 ceases to be of service when the number rises above 150. — On 

 the temperature in Geissler's tubes, by K. Kerkhof. The tem- 

 perature in the capillary tube of a Geissler tube was measured 

 by means of the change of resistance of a fine platinum wire. 

 The results were not in agreement with Wiedemann's law, that 

 the temperature is inversely proportional to the section of the 

 tube. — Magnetic images, by H. Jaeger. — The experimental 

 determination of the capillary constants of condensed gases, by 

 L. Grunmach. The method used is based upon the production 

 of capillary waves by the prongs of a tuning fork and the appli- 

 cation of a formula developed by Lord Kelvin. It had been 

 found previously to yield satisfactory results with ordinary 

 liquids and molten metals, and has worked well with liquefied 

 gases. Results are giv.en for sulphur dioxide, ammonia, Pictet's 

 liquid and chlorine. The application of the formula of Ramsay 

 and Shields to these observations proves that there is no associ- 

 ation of the molecules in liquid ammonia and sulphur dioxide. 

 In the case of chlorine there appears to be a certain amount 

 of association. — The motion of an electrified particle in an 

 electrostatic field, by E. Riecke.— On stratification in a stream 

 of electrified particles, by E. Riecke. — On the ionisation of 

 electrified gases and the unipolar discharge in glowing bodies, 

 by J. Stark. — On the thermoelectrical behaviour of some oxides 

 and metallic sulphides, by E. van Aubel. The results do not 

 confirm the researches of Abt on the same subject. — On the 

 molecular heat of compound bodies and the Neumann-Joule- 

 Kopp law, by E. van Aubel.— On the theory of radiation. A 

 reply to the criticism of Planck, by W. Wien. 



SOCIETIES AND ACADEMIES. 

 London. 



Royal Society, Febrnary 28— "On the Structure and 

 Affinities of Fossil Plants from the Palaeozoic Rocks. IV. 

 The Seed-like Fructification of Lepidocarpon, a Genus of 

 Lycopodiaceous Cones from the Carboniferous Formation." 

 By D. H. Scott, M.A., Ph.D., F.R.S., Hon. Keeper of the 

 Jodrell Laboratory, Royal Gardens, Kew. 



A short account of the new genus Lepidocarpon has been 

 given in a note communicated to the Royal Society last August ^ ; 

 the present paper contains a full, illustrated description of the 

 fossils in question, together with a discussion of their morphology 

 and affinities. 



The strobilus of Lipidocarpon Lomaxi, the Coal-measure 

 species, is, in its earlier condition, in all respects that of a 

 Lepidoslrobus, of the type of L. Oldhamius. 



1 " Note on the Occurrence of a Seed-like Fructification in certain 

 alaeozoic Lycopods," Roy. Soc. Prec, vol. Ixvii. p. 306. 



NO. 1638, VOL. 63] 



In each megasporangium, however, a single megaspore or 

 embryo sac alone came to perfection, filling almost the whole 

 sporangial cavity, but accompanied by the remains of iis abortive 

 sister-cells. An integument ultimately grew up from the sporo- 

 phyll, completely enclosing the megasporangium, and leaving 

 only a narrow slit-like opening, or micropyle, along the top. 

 As shown in specially favourable specimens, ho\.\\ oi Lepidocarpon 

 Lomaxi and of L. Wildianiim, the more ancient Burntisland 

 form, the functional megaspore tiecame filled by a large-celled 

 prblhallus, resembling that of the recent Isoeles or Selaginella. 

 The whole body, consisting of the sporophyll, bearing the integu- 

 mented megasporangium and its contents, became detached 

 from the strobilus, and in this isolated condition is identical 

 with the "seed" described by Williamson under the name of 

 Cardiocatpon anomalum, which, however, proves to be totally 

 distinct from the Cordaitean seed so named by Carruthers. 



The seed like organs of Lepidocarpon are regarded by the 

 author as presenting close analogies with true seeds, but as 

 differing too widely from the seeds of any known Spermophyta 

 to afford any proof of affinity. The case appears rather to be 

 one of parallel or convergent development, and not to indicate 

 any genetic connection between the Lycopods and the Gymno- 

 sperms, or other Phanerogams. 



"On the Theory of Consistence of Logical Class-frequencies 

 and its Geometrical Representation." By G. Udny Yule, 

 formerly Assistant Professor of Applied Mathematics in Uni- 

 versity College, London. Communicated by Prof. K. Pearson, 

 F.R.S. 



Geological Society, February 20.— J. J. H. Teall, F.R.S. , 

 presideat, in the chair. — Prof. J. B. Harrison, alluding to a 

 series of views of parts of the interior of Biritish Guiana, 

 which he laid on the table, remarked that the photographs had 

 been taken by his colleague, Mr. H. I. Perkins, Acting Com- 

 missioner of Mines in British Guiana, during their recent 

 geological investigations into the structure of the goldfields 

 of that colony. The views well illustrate the general character- 

 istics of the densely wooded country in which the gold-bearing 

 areas occur, and give some idea of the difficulties which affect 

 the work of the mining prospector and of the field-geologist in 

 that colony. Several of the photographs illustrate rapids, 

 cataracts and falls which so frequently occur along the courses 

 of some of the vast rivers of that part of South America, and 

 show the differing forms of weathering of various igneous rocks 

 and of horizontally-bedded sandstones and conglomerates in the 

 tropics. With reference to a few rock-specimens exhibited. Prof. 

 Harrison stated that they were of diamond-drill cores from the 

 Omai Creek claims on the Essequibo River, and that they fairly 

 represented the principal auriferous rocks of that district. Omai 

 Creek is a small stream flowing into the Essequibo at about 130 

 miles above its mouth, and the country through which it flows 

 is usually diabase (dolerite) and its decomposition-products. 

 From a part of the bed of one of the tributaries of this stream 

 (Gilt Creek), about 500 feet in length by 50 in breadth, some 

 60,000 ounces of gold and some hundreds of small diamonds 

 have been recovered by the somewhat crude methods of working 

 hitherto in use. — Prof. Edward Hull made a communication, 

 illustrated by lantern slides, on the submerged valley opposite 

 the mouth of the River Congo. The position of this submerged 

 valley has been ascertained by Mr. Edward Stallybrass and 

 Prof. Hull by contouring the floor of the ocean with the aid of 

 the soundings recorded on the Admiralty charts. The sides of 

 the valley are steep and precipitous and clearly defined, the 

 width varying from two to ten miles, and the length across the 

 continental platform being about 122 miles. It is continuous 

 with the valley of the Congo, and its slope is uninterruptedly 

 downward in the direction of the abyssal floor. The steepness 

 of the sides indicates that they are formed of very solid rocks. 

 Several other 'submerged valleys off the coast of Western 

 Europe were described for comparison. In most cases the 

 landward end of the submerged river-channel is filled with silt, 

 &c., for some distance from the mouth of the actual river ; but 

 farther out its course becomes quite distinct towards its 

 embouchure at the edge of the continental platform. 

 Among the valleys specified were those off the mouth 

 of the Tagus and the Lima, the Adour and the Loire, 

 and those in the English and Irish Channels. The 

 following communication was read: — The geological succession 

 of the beds below the Millstone Grit series of Pendle 

 Hill and their equivalents in certain other parts of England, by 

 Dr. WheeUon Hind and J. Allen Howe. Part i. of this paper 



