1 90 



NATURE 



[February 9, 1922 



(d) Some other Papers. 



The papers delivered before the Section dealt with 

 a diversity of subjects. Mr. Matthews contributed a 

 paper on "The Distribution of Certain Elements of 

 the British Flora." These show peculiarities of geo- 

 graphical distribution in Great Britain which, when 

 studied cartographically and compared with their 

 occurrence on the Continent, seem to furnish addi- 

 tional evidence in favour of the views of some of 

 the earlier students of the problems of plant re- 

 population after the Glacial period. The Palaearctic 

 flora of post-Glacial times is now confined to the 

 highest Scotch mountains, and has been replaced else- 

 where in Great Britain by a temperate flora from 

 the Continent. 



Mr. Hamshaw Thomas gave an account of his in- 

 vestigations into the structure of some angiospermous 

 fruits discovered in the Middle Jurassic rocks of York- 

 shire. Each fruit, which shows traces of what may 

 be a stigma, contains about eight small seeds clothed 

 with a double fibrous integument. While the speci- 

 mens are obviously Angiosperms in that the seeds are 

 developed inside a fruit-wall, the seeds themselves 

 show resemblances to some of the primitive Gymno- 

 sperms or Pteridosperms, and may yet throw light 

 on the origin of the flowering plants, that difficult 

 problem referred to by Charles Darwin as an 

 "abominable mystery." 



Prof. McLean Thompson, in his account of the 

 floral development of the cannon-ball tree and its 

 bearing on the floral morphology of the Mvrtales, put 

 forward the view that the gigantism of cells and 

 sterility of pollen found associated with the floral lop- 

 sidedness had arisen as a mutation. 



Dr. Batten gave an account of the organs of attach- 

 ment in Polysiphonia ; Miss Saunders put forward a 

 theory of the morphological nature of the Dicotyledon 

 shoot, viz. that each internode consists of an axial 

 core clothed with a skin of the extended bases of the 

 leaves immediately above. 



Major Hurst's pap>er on "The Origin of the Moss 

 Rose " raised many interesting problems, particularly 



in view of the recent cytological work on this genus. 

 Tackholm and Blackburn and Harrison ascribe 

 hybridity as the cause of the irregular distribution of 

 unpaired chromosomes found to be associated with 

 abortive pollen. Darwin's view that the moss rose is 

 a bud variation of the familiar cabbage rose (Rosa 

 centifolia) seems to be confirmed. The moss rose 

 would appear to have arisen as a mutation, and to have 

 been in cultivation only since the end of the seven- 

 teenth century, while the cabbage rose has been cul- 

 tivated for more than two thousand years. In con- 

 clusion. Major Hurst expressed his views thus : — " In 

 terms of the recent development of the chromosome 

 theory of heredity it may be said that the moss muta- 

 tion arose through the presence of an additional factor 

 in a single locus of a single chromosome of a somatic 

 cell." 



"The Behaviour of the Somatic Nucleus in Develop- 

 ment " formed the subject of a paper by Prof. 

 McLean, who described briefly the discovery of the 

 binucleate phase, and discussed its significance in 

 relation to senescence, normal histogenesis, and 

 somatic segregation of characters. 



The eminent Dutch botanist. Dr. J. P. Lotsy, fur- 

 nished a paper on "Factors of Evolution." He depre- 

 cated the custom of tracing the course of evolution 

 through the genealogy of species which exist only as 

 a conception. Nature produces individuals, some of 

 which interbreed freely and may be termed " syn- 

 gameons," and these have been mistaken for 

 species. The course of evolution should rather be 

 traced by the genealogv of the gametes, and the ques- 

 tions of fundamental importance are : Can a gamete 

 vary by itself without loss of chromosomes? And 

 are such variants transmissible? The only trans- 

 missible changes proved to occur are the results of 

 crossing, and thev transgress the limits of the 

 Linnean species. Not enough attention has yet been 

 given to the crosses between gametes differing In the 

 number of chromosomes and the consequent Irregular 

 distribution which causes changes that may even 

 simulate Mendellan segregation. 



E. N. M. T. 



Mont Blanc Meteorological Observations. 



nr HE seventh volume of Annales de rObservatoire 

 -'■ M^t^orologique Physique et Glaciaire du Mont 

 Blanc (altitude 4350 metres) has now been published, 

 under the direction of M. J. Vallot, founder and director 

 of the observatory, following the sixth volume which 

 was published in 1905 (tome 7, Paris, G. Steinheil, 

 6diteur, 1917). It records the death of Janssen in 

 1908 and the transformation of the provisional society 

 of his observatory at the summit (4808 metres) into 

 a societe definitive which placed that observatory also 

 under the direction of M. Vallot. Both were 

 utilised in 1908, but that on the summit became not 

 merely uninhabitable, but dangerous, and it was there- 

 fore demolished In 1909. Since that date work has 

 been carried on only at M. Valot's observatory, which 

 he had placed at the disposal of the society. The 

 volume referred to deals only with the work accom- 

 plished before the union of the observatories. The 

 researches made at the cost of the society have been 

 published en resume in the Compies rendus ; those 

 which cannot find a place there, as well as reports in 

 extenso, will appear in later volumes of the Annales. 



The publication of the seventh volume has been 



delayed by M. Vallot 's ill-health and by the war. 



It contains two papers by M. Henri Vallot, one on 



some modern maps of the massif of Mont Blanc, 



NO. 2728, VOL. 109] 



the other on the progress made with the map on the 

 scale of I : 20,000 by the brothers Vallot ; also some 

 " Notes exp>erimen tales sur le mode d'action des 

 cures d'altltude," by M. G. Kuss, of the Sana- 

 torium d'Angicourt. The greater part of the volume 

 is occupied by an elaborate discussion by M. J. Vallot 

 of the barometric calculation of altitudes, particularly 

 oh the correction for the diurnal variation of the 

 temperature of the air, which with the ordinary 

 formula may cause differences of as much as a 

 hundred metres in the estimation of a difference of 

 level of 2800 metres. The discussion leads up to the 

 suggestion for correcting the value of the difference 

 of height obtained by the "classical " tables by a cor- 

 rection based on the mean temperature of the day for 

 the base station, on a temperature for the upper station 

 obtained from the base temperature by subtracting 

 one decree for every 154-5 metres, and on a special 

 correction for diurnal variation of temperature based 

 on a month's observations In 1887 of Mont Blanc with 

 reference to Geneva. Suitable winter values have 

 still be to be ascertained. Examples of the applica- 

 tion of the method are given and a defence of the 

 procedure in view of recent work on the subject, 

 which Is of practical Importance for meteorological 

 maps as well as for Alpinists. It Is, however, full 



