5o6 



NATURE 



[January 2, 191^ 



and some varieties will not set with certain pollen. 

 Out of nearly 3000 insects observed last spring visit- 

 ing the blossoms of the various fruit bushes and 

 trees, 88 per cent, were hive-bees, 5J per cent, bumble 

 and other wild bees, and 6A per cent, flies, ants, 

 beetles, wasps, and other insects ; but the latter g'roup 

 have not fluffy bodies for carrying pollen, and amuse 

 themselves eating the pollen. — H. M. Chibber : The 

 morphology and histology of Piper Betle, Linn. 



M.ANCHKSTER. 



Literary and Philosophical Society, November 26, 

 1912. — Prof. F. E. Weiss, president, in the chair. — 

 Prof. F. E. Weiss : The root-ape.\ and young root 

 of Lyginodendron. This genus, one of the Coal- 

 Measure plants, the remains of which are frequentlv 

 preserved in the calcareous nodules of the Lancashire 

 coal seams, is of peculiar interest, owing to the posi- 

 tion assigned to it and allied genera. Fern-like in 

 appearance, it is known to have borne seeds of con- 

 siderable complexity, and it has therefore been placed 

 in a newly established group of PteridosperniEe, be- 

 tween the true ferns and the flowering plants. As 

 among other characters, these two groups are dis- 

 tinguished by the possession of a single cell or multiple 

 group of such cells at the apex of their roots, an 

 investigation of the root-tip of Lyginodendron is of 

 some interest. Careful examination of numerous sec- 

 tions tends to prove that the structure of the root-tip 

 of Lyginodendron agrees more closely with that of 

 the ferns than that of the flowering plants. — Dr. Kurt 

 Loewenfeld : The importance of autograph documents 

 for the history of science (part ii.). The author dealt 

 chiefly with letters by Priestley and Lavoisier. These 

 included letters to Sir Joseph Bank and Josiah Wedg- 

 wood, and others relating to the Birmingham riots 

 in 1791. The draft of a letter of the French chemists, 

 offering to make good all Priestley's losses through 

 the riots, was read. It is noteworthy, especially con- 

 sidering the scientific relations between Lavoisier and 

 Priestley, that this draft had corrections by the hand 

 of A. L. Lavoisier, which makes it evident that this 

 letter originated from him. 



Dublin. 

 Royal Dublin Society, December 17, 1912. — Prof. James 

 Wilson in the chair. — J. Adams ; The germination of 

 the seeds of some dicotyledons. Investigations were 

 made to determine how long the seeds of a particular 

 species of plant remain in the ground before they 

 germinate. Observations were made on 278 different 

 species of plants belonging to 190 genera, and repre- 

 senting fifty-eight families. In some cases the seeds 

 germinated after a few weeks, while in others, such 

 as the hawthorn, a year and a half was required. 

 The characters of 158 species not included in Lub- 

 bock's treatise are given. The majority of the seeds 

 used were of British species, but a few exotic species, 

 such as almond, fig, &c., were included. — Prof. T. 

 Johnson : Bothrodendron (Cydostigma) Kiliorkcnse, 

 Haughton, sp. The paper treats of specimens 

 obtained by the author at Kiltorkan, co. Kilkenny, and 

 of others in the collections in Dublin and London. 

 .^n attempt is made to prove that B. Kiltorkense, 

 abundant at an epoch when Lepidodendron and Sigil- 

 laria were either non-existent or, if formed, still 

 relatively rare, and showing pronounced calamitoid 

 characters — including transverse zonation (nodal 

 diaphragms?) and vertical fluting — is the earliest and 

 best representative of the ancestral stock from which 

 the Lycopodiales and Equisetales took their common 

 origin. — Prof. J. Joly : .\ method of microscopic 



NO. 2253, VOL. 90] 



measurement. This is one which apparently has not 

 hitherto been applied in microscopy; it 'consists in 

 observing with the camera lucida the object to be 

 measured, in such a manner that its image appears 

 upon a sheet of paper on which two lines have been 

 drawn slowly diverging from a point. By shifting 

 the paper the image is made to fit exactly between 

 the lines, the position where it fits being marked. 

 A similar operation is performed with a suitably 

 divided millimetre scale. From the data so obtained 

 a simple calculation gives the diameter of the object. 

 —Prof. H. H. Dixon and W. R. G. Atkins: Osmotic 

 pressures in plants, (a) Methods of extracting sap 

 from plant organs ; (b) osmotic pressures and electrical 

 conductivities of the saps of plant organs, (a) Vari- 

 ous methods of obtaining sap for microscopic con- 

 ductivity measurements are discussed. It is shown 

 that the sap pressed from living tissues may have a 

 concentration very different from that in the vacuoles 

 of the ce'Is, the protoplasm of which must b.- rendered 

 permeable before the unaltered sap can be pressed. 

 Exposure to heat, toluene vapour, or chloroform is 

 open to objection. Treatment with liquid air seems 

 free from objection, renders the membranes permeable, 

 and allows the unaltered sap to escape. Cryoscopic 

 and conductivity measurements on this true sap show 

 that it is usually much more concentrated than that 

 pressed from the untreated organs. An extreme 

 example of this is afforded by the leaf of Chamaerops 

 hiimilis. (b) The fundamental error in previous cryo- 

 scopic and conductivity measurements of the sap of 

 plants, which was pointed out in the foregoing paper 

 (a), renders revision of previous results necessary. 

 The present paper contains a number of results of 

 cryoscopic determinations, osmotic pressures resulting 

 from them, and conductivity measurements made on 

 saps obtained from organs treated with liquid air. 



Edixburgh. 



Royal Society, December 16, 1912. — Prof. Bower, 

 vice-president, in the chair. Irvine Masson : The pre- 

 cipitation of salts by corresponding acids. If B is the 

 initial solubility in pure water, and b the solubility 

 for acidity a, then within fairly wide limits it is found 

 that the ratio a/(B — b) is a constant, on which the 

 change of temperature seems to have little effect. Its 

 value is very nearly unity for the chlorides and nitrates 

 experimented with. The main object of the paper was 

 to connect by means of this empirical formula the two 

 recognised methods for studying experimentally these 

 relations, namely, the " solubility " method, which 

 determines directly the solubility of a salt in water 

 containing the acid in varying concentrations, and the 

 " precipitation " method, as used by Gibson and 

 Denison, which aims at ascertaining the minimum 

 concentration of aqueous acid which when added in 

 small quantities to the saturated aqueous salt solution 

 causes deposition of salt. Prof. Seward and N. 

 Bancroft : Jurassic plants from Cromarty and Suther- 

 land. The matei' t included Hugh Miller's collection 

 in the Royal Scott Museum, a section of a cone in 

 Dr. Kidston's collection, petrified wood from Helms- 

 dale lent by Dr. Home, and two fossils found by Dr. 

 Nathorst on the Sutherland coast. The examination 

 of the material had led to the recognition of six new 

 species, I'hinnfeldia scottica, Brachyphyllum eathiense, 

 MascuJostrobiis Woodwardi, Canities Juddi, Cedro- 

 xyloH Honiei, and Sirobilites Millcri. Prof. F. J. 

 Cole : A monograph on the general morphology of 

 My.xinoid fishes, based on a study of Myxine. Part 

 V. — The anatomy of the gut and appendages. 

 C Tate Regan:' .Antarctic fishes of the Scottish 



