July 20, 1905] 



NA TURE 



287 



une description de la glauconie qu'elles renferment, par 

 Gabriel W. Lee. The work was undertaken under the 

 direction of Sir John JVIurray, whose large collection of 

 phosphalic nodules had been greatly enriched by the con- 

 cretions dredged off the Cape of Good Hope by the steamer 

 of the Department of Agriculture, and presented by Dr. 

 (iilchrist, the Government biologist. The concretions were 

 found beyond the loo-fathom line down to depths of 800 

 fathoms. Their occurrence, as already pointed out by 

 Sir John Murray, is closely connected with the oceano- 

 graphical question of the variability of' temperature in 

 certain regions. The mingling of two currents of different 

 temperature is necessarily attended by a great mortality 

 among the creatures living in these waters, and their 

 dead bodies falling to the bottom produce ammonia and 

 phosphate of lime. There can be little doubt that the 

 glauconife and phosphates found in geological strata have 

 been formed under similar conditions. In the material 

 from the Agulhas Bank two kinds of nodules were 

 found : — (i) those with Fcraminifera and other calcareous 

 organisms ; (2) those without carbonate of lime and with 

 the glauconite grains cemented together by phosphatic 

 jnatter. These implied different modes of formation. Mr. 

 Lee recognised two kinds of glauconite in the phosphatic 

 nodules, the occurrence in the one kind being in the form 

 of grains with definite contours, in the other in the form 

 of a diffused pigment. — Note on some of the magnetic 

 properties of demagnetised and annealed iron : James 

 Russell. The iron was demagnetised by one of three 

 methods, namely, by decreasing reversals of magnetic 

 force co-directional with the field to be afterwards applied 

 in the study of the permeability, by decreasing re- 

 versals of a transverse force, or by annealing. The 

 permeabilities after these processes of demagnetisation 

 were carried out were then compared, and various interest- 

 ing conclusions arrived at. One very remarkable result 

 was that, however much the values of the permeability 

 differed under these varied conditions, the value of the 

 coercive force (as defined by Hopkinson) was almost 

 exactly the same in all cases. — Certain mathematical 

 instruments for graphically indicating the direction of re- 

 fracted and reflected light rays : J. R. Milne. These 

 simple devices were not only useful in demonstrating the 

 course of reflected and refracted rays, but could also be 

 effectively used in graphically solving problems in geo- 

 metrical optics the algebraic solution of which presented 

 insurmountable difficulties in the way of carrying out the 

 necessary eliminations. — On the hydrodynamical theory of 

 seiches : Prof. Chrysta.1. This paper contained the mathe- 

 matical solution of problems suggested by the phenomena 

 of seiches in lakes, and showed how the periods of the 

 various possible seiches and the positions of the nodes 

 were affected by the contour of the lake bottom. — On a 

 group of linear differential equations of the second order, 

 including Chrystal's seiche-equations as special cases : Dr. 

 Halm. This formed an important sequel to the fore- 

 going paper, giving a mode of arriving at a solution of a 

 case in which the direct method led to a slowly con- 

 verging series, ill-suited for numerical determinations. — 

 K monograph on the general morphology of the myxinoid 

 fishes, based on a study of myzine, part, i., the anatomy 

 of the skeleton : Frank J. Cole. By controlling the dis- 

 sections by charts reconstructed from serial sections, the 

 author obtained many results of importance in working 

 out the micro-anatomy of the skeleton. Previous descrip- 

 tions have thus been much e.xtended, and the phylogenetic 

 origin of the myxinoid skeleton may now be shown to be 

 much simpler than has been hitherto supposed. 



July 3.^Prof. Geikie in the chair. — The plant 

 remains in the .Scottish peat mosses, part i. : Francis 

 J. Lewis. The paper contained a detailed account of the 

 botanical stratification of peat mosses in the Scottish 

 southern uplands, the discussion being in every case based 

 upon evidence derived from freshly cut holes or from 

 borings. The geological horizons were determined in most 

 cases by the fact that the mosses rested on moraines 

 which were known to belong to one of the Glacial periods. 

 The conclusions were in full accord with the views 

 originally put forward by Prof. James Geikie, and demon- 

 strated the existence of the third, fourth, and fifth periods 

 of glaciation in Scotland, those, namely, which are dis- 



NO. 1864, VOL. 72I 



tinguished as (3) the district ice sheets, (4) the mountain 

 valley glaciers, (5) the corrie glaciers. — Dissociation of the 

 action of the auricles and ventricles : Dr. W. T. Ritchie. 

 The paper contained an account of curious cases of heart 

 block, a subject first studied scientifically by Gaskell. 

 The graphs of the various pulse rhythms were obtained 

 side by side, enabling the eye at a glance to contrast them 

 and so prove the absolute independence of the action of the 

 auricles and ventricles. — Cape hunting dogs {Lycaon pichis) 

 in the gardens of the Royal Zoological .Society of Ireland : 

 Prof. D. J. Cunningham. The chief interest attached 

 to these dogs was that they had been for the first time 

 reared in captivity. The parents had been got from 

 Holland, and during the four years 1896 to 1900 there 

 had been four litters, but only three of the puppies had 

 been brought to maturity. The peculiar colouring of the 

 adult dog with its yellow and white patches was absent 

 in the puppy stage, but gradually appeared as the animal 

 grew older ; also the dark band down the forehead became 

 more marked with age. The animals were very in- 

 tractable in captivity. .\n attempt to obtain a cross with 

 a collie failed, the collie when introduced into the cage 

 showing symptoms of excessive fear, while the male 

 Lycaon paid not the least attention to her. The period of 

 gestation in the case of the Cape hunting dog was found 

 to be eighty days, somewhat longer than in the case of 

 the domestic dog. — The Alcyonarians of the Scottish 

 National Antarctic Expedition : Prof. J. A. Thomson and 

 James Ritchie. The collection contained si.x new species, 

 and specimens of three forms previously obtained by the 

 Challenger. These were found in various latitudes, the 

 furthest south specimen having been obtained in 

 S. lat. 74°, off Coats Land. Our knowledge of the geo- 

 graphical distribution has been thus much extended. Of 

 the beautiful Umbelliila dtirissiiim the Challenger obtained 

 one young specimen from the south of Yedo, while Mr. 

 Bruce was fortunate in obtaining about a score of speci- 

 mens, some of which are larger, older, and of more 

 vigorous growth than that which KoUiker described in 

 the Challenger reports. — The theory of determinants in 

 the historical order of development up to 1852 : Dr. 

 Thomas Muir. — On the action of radium bromide on the 

 electromotive phenomena of the evebail of the frog ; Prof. 

 McKendrick and Dr. W. Colquhoun. It has been 

 known since 1871 that when the fresh excised eye of a 

 frog is connected by unpolarisable electrodes with a 

 sensitive galvanometer an electric current may be detected, 

 and that definite variations take place in that current 

 when the retina is exposed to the action of light. It is 

 also well known that salts of radium are luminous in the 

 dark, and that when a tube containing radium is pressed 

 against the closed lid of the eyeball a luminous effect is 

 produced. It was of interest to ascertain whether this 

 luminosity was due to the radium causing fluorescence 

 of any of the structures of the eyeball, or whether it 

 was due to the direct action of the radium emanations 

 on the retina itself. The radium employed was kindly 

 lent by Dr. Hardy, of Cambridge. The conclusions were 

 as follows : — (i) The light emanating from radium 

 bromide affects the electromotive phenomena of the living 

 retina of the frog in a manner similar to that of light, 

 although to a considerablv less degree ; (2) its action is 

 not due to fluorescence of any of the structures of the 

 eyeball, but to direct action on the retina ; (3) the retina 

 of the frog will respond to emanations of radium passing 

 through cardboard, blackened paper, thin glass, and 

 aluminium foil, emanations which, when allowed to fall 

 on the human eye in a perfectly dark chamber, do not 

 give rise to a luminous sensation ; (4) the frog's eye is 

 sensitive to the feeble light emitted from the surface 

 of fluorescible minerals and fluids rendered fluorescent 

 by radium ; (5) the ^8 rays are responsible for most of 

 the effects observed, but after they have been largely 

 excluded by thick glass a slight effect still persists, due 

 presumably to the y rays ; (6) monochromatic light em- 

 ployed in a photographic chamber may still affect the 

 electromotive phenomena of the living retina of the frog ; 

 (7) no satisfactory evidence could be obtained of the 

 action of the ultra-violet rays of a lamp filtered through 

 a Wood's screen. The slight movement of the galvano- 

 meter observed with light " off " might possiblv be ac- 



