December 30, 1920] 



NATURE 



587 



of Eucalyptus. The author has previously expressed 

 the opinion that important results are awaiting those 

 who more thoroughly investigate trees attributed to 

 existing forms instead of givmg too much attention 

 to the search for rare and bizarre forms. This paper 

 directly illustrates this point, and the following New- 

 South Wales trees are proposed as new. All yield 

 valuable timbers : — (o) The Blue Mountains maho- 

 gany, attributed without doubt to Eucalyptus resinu 

 fera, Benth., for so many years, has pale-coloured, 

 tissile timber very sharply ditferent from that species, 

 (fr) The tall grey gum of the counties of Gloucester 

 and Durham, hitherto named E. punclata, var. grandi- 

 flora. and therefore as.sumed to have a deep red 

 timber, turns out to have pale-coloured, tough timber 

 allied to that of the spotted gum (£. maculata. 

 Hook.), (c) Less was known of this tree, the type 

 of which comes from VVyee, north of Gosford. It is 

 ? R""'".^' guf" with a deep red-coloured timber, possess- 

 ing botanical characters intermediate between E. 

 longifolia, Link and Otto (woolly-butt), and E. punc- 

 tata, DC, the Ijest known of our grev gums. — L. A. 

 Cotton and Miss M. Peart : The calculation of the 

 refractive inde.x in random sections of minerals. The 

 method employed is a graphical one, in which use is 

 made of the stereographic projection. Both refractive 

 indices for any given mineral section can be cal- 

 culated when the form and position of the indicatrix 

 are known. The principle is simple, and has been 

 applied by Miss Peart to the evaluation of the refrac- 

 tive indices of the plagioclase felspars for cleavage 

 flakes parallel to the (oio) and (ooi) crystallographic 

 forms. 



Wa.shington, D.C. 



National Academy ol Sciences (Proceedings, vol. vi., 

 No. 4), .\pril, 1920.— N. L. Bowen: Differentiation 

 by deformation. The deformation of an igneous mass 

 during crystallisation, with consequent separation of 

 liquid from crystals, has frequently been suggested 

 as a cause of variation of igneous rocks, and this sug- 

 ^jestion is here discussed in considerable detail under 

 the headings of discontinuous differentiation, mono- 

 Tiiincralic types as members of composite intrusivcs, 

 rnonomineraiic types as simple " intrusives," comple- 

 m.nt.iry dvkes, primary banding, and alkaline rocks. 



1. H. Morgan, A. H. Sturtevant, and C. B. Bridget: 

 rill- evidence for the linear order of the genes.— 

 ('. W. Meti : The arrangement of genes in Droso- 

 phila virilis. Two papers in continuation of the dis- 

 1 ussion of the linear versus spatial arrangement of 

 th.' genes.— G. W. Stewart : The functions of intcn- 

 NJty and phase in the binaural location of pure tones. 

 With frequencies of loo to 1200 d.v., phase is the 

 I hief factor in Inralisation with pure tones, the inten- 

 sitveflfert being practicallv m7. or at least verv small. — 

 I,. T. E. Thonpton, C. N. Hickman, and S. RIBolt : 

 The measurement of small time-intervals ami .some 

 .ipplications. principallv ballistic. A description of a 

 new apparatus for indicatint; verv small intervals of 

 lini.- with application to the ballistics of small arms.— 

 U. M. Sheldon: Charcoal activation. The variations 

 dill- til heat treatment may be explaine<l bv assuming 

 th.it the structure of the charcoal is mollified or that 

 thi- air was the agent causing the variations. Data 

 are given an»l inlerpretid on the basis of the latter 

 assumption.— J. K. Whlllemore : The starting of a 

 ship. A discussion with simple integral equations of 

 tlw problem of a particle movintj under the action 

 of tangential forces dependent on the velocity alone, 

 with suggested applications to marine rngineerinc and 

 to the study of the laws of liquid resistance. _ F. L. 

 Hitchcock ; A thermmlvnamic sludv of electrolytic 

 ••olufions. The adoption of Gibbs's principle of 

 chemical potential leads to the extension of the 

 ordinary theories of melting point, heat polrnti.-il, .ind 

 NO. 2670, VOL, I06l 



mass law. These extensions are the result of the 

 presence in the expression of the chemical potential 

 of the solvent -for the terms in the second and higher 

 powers of the concentrations. — L W. Bailey : The 

 formation of the cell-plate in the cambium of the 

 higher plants. Continuation of a previous paper in- 

 dicating that the type of cell-plate formation there 

 described is of frequent occurrence, and promises to 

 be significant in any general discussion concerning 

 the dvnamics of cytokinesis and karyokinesis.^ — L .\. 

 Barnett : Functionals invariant under one-parameter 

 continuous groups of transformations in the space of 

 continuous functions. Examples of one-parameter 

 continuous groups are given, with in each case a 

 functional invariant in terms of which each invariant 

 of the group is expressible. — H. Shapley : Thermo- 

 kinetics of Lioinetopum apiculatum. Mayr. A curve 

 is obtained relating the speed of these ants to the 

 temperature. The .speed is less erratic at higher tem- 

 peratures, and increases over a 30° C. range from 

 044 cm. to 660 cm. per second. — J. Loeb : The 

 influence of ions on the osmotic pressure of solutions. 

 A summary and discussion of an extensive .series of 

 experiments. .\t lower concentrations of the elec- 

 trolvte the influence of the anion increases more 

 rapidiv with increasing concentration of the elec- 

 trolvte than the depressing effect of the cation, -while 

 at higher concentrations the reverse occurs. The 

 turning point lies for a number of electrolytes at a 

 molecular concentration of about m/2s6. — D. H. 

 Tennent : Evidence on the nature of nuclear activity. 

 The basophilic bodies are not in the nature of 

 chromidia, but are the result of indirect nuclear 

 activity. The explanation offered for the formation 

 of the basophilic extra-nuclear bodies described is in- 

 tended to he sufffestive rather than conclusive. — A. C. 

 Hardy : A stiidv of the p«?rsistence of vision. 

 Measurement of the persistence of vision for several 

 colours within a cone the semi-vertical angle of which 

 is about 40°. — R. Pearl : A contribution of genetics 

 to the practical breeding of dairy cattle. A summary 

 of investigations extending over manv years with 

 respect to the value of 224 Jersev Registry of Merit 

 sires in relation to their transmitting aualities in 

 milk.production. This work gives the breeder in- 

 formation of a sort that he has never had before, and 

 that enables him at once to form a real jwlgment of 

 the worth of various bulls which appear in the 

 pedigree of Jersey cattle. 



(Proceedings, vol. vi., No. 5), May, 1920. — 

 }L H. Laughlin : Calculating ancestral influe/ice 

 in man. The problem is that of measuring 

 ancestral influence by tracing chromosomes. By 

 applying principles of combination and chance, 

 the ' probability that a given complex situation 

 will result froin a given set of constituent conditions 

 may be formulated mathematically. The formul» 

 here given are foundational, and are stated in ^neral 

 terms the validity of which depends upon their pre- 

 senting correct mathematical pictures of chromosomal 

 processes which work out in the germ-cell cycle. — 

 (1. Mcdei and J. K. McClendon : The effect of'antes- 

 thetics on living cells. -An attempt to determine the 

 effect of different anaesthetics on several activities or 

 properties of living ri-lls. Not all an.-csthetics hod 

 the same effect, and the same ana-sthelic affected 

 the same activity of a plant differently from ait 

 animal, and different aclivities of the same cell 

 differently. .Ml the ana-sthelics tried increased plnnt- 

 rell respiration and ix-rmenbility.— R. A. Daly : A 

 general sinking of si-.i-U'Vel in recent limes. The 

 farts at hand seem to permit belief in the synchrony 

 of the different strand-markings and emergences here 

 considered, but further in>«stigalion is needed. — C. C. 

 Lliile : A note on the human sex ratio. A brief atudv 



