November io, 1910] 



NATURE 



59 



and Praf. F. E. Weiss described some experiments on 

 the inheritance of colour in the pimpernel. The latter 

 author crossed Atiagallis arvensis and A. coerulea (the 

 red and blue pimpernels). The red colour proved to be 

 dominant, while in the /, generation there was complete 

 segregation into red and blue forms. This is another 

 ^resting case of a recessive blue in the Primulaceae. 



Fungi. 

 The fungal papers were taken on Thursday morning 

 before the president's address. Prof. Duller discussed the 

 function and fate of the cystidia of Coprinus. The author 

 confirmed Brefeld's view that the cystidia act as props 

 to keep the gills from touching each other. He pointed 

 out that this is necessarj- to allow for the free escape of 

 the rif)e spores. The cystidia themselves disappear bv a 

 process of autodigestion just before the basidia in their 

 immediate neighbourhood are ready to discharge their 

 spores. In the discussion on this paper Mr. Wager sug- 

 C-^sted that the cystidium must be regarded as having 

 n phylogenetically derived from the basidium. Mr. 

 E. Lechmere read an interesting pa|>er on the methods 

 asexual reproduction in a species of Saprolegnia. In 

 ging-drop cultures great variation was found in the 

 aviour of the zoospores, the method of discharge, and 

 shape of the sporocyst. Variations of form, &c.. sup- 

 d to be characteristic of distinct genera of the Sapro- 

 -ieae were found within the limits of this single species. 

 :. \ . H. Blackman described a form of nuclear division 

 inrermediate between mitosis and amitosis in Coleosporiunt 

 Ttissilagiiiis. A spindle is formed on which granular 

 chromatin collects, and is then drawn apart towards the 

 poles. The chromatin is not aggregated into definite 

 chromosomes. Mr. Harold Wager, in a paper on chromo- 

 some reduction in the Hymenomycetes, maintained that 

 normally only two nuclei (each containing four chromo- 

 soniesl fuse in the basidium. During the division of the 

 fusion nucleus the spireme breaks up into eight chromo- 

 somes, reduction being brought about in a simple manner 

 by the distribution of the chromosomes to the two 

 daughter nuclei. Mr. F. T. Brooks described his investi- 

 gations into the cause of the silver-leaf disease of fruit 

 trees. These experiments are still proceeding, but, 

 although not absolutely proved, the available evidence 

 points, as previously suggested by Percival and Pickering, 

 to Stereum purpureum as the probable cause of the 

 disease. 



Morphological and other Papers. 

 .\lthough only an afternoon session (on Monday) was 

 available for morphology, the papers proved so attractive 

 that the section sat for nearly three and a half hours. 

 Prof. F. O. Bower led off with two papers. The first 

 was a short note on Ophioglossum palmatum. The 

 divided character of the leaf-trace supports the conclusion, 

 previously arrived at from its external morphology", that 

 O. palmatum is one of the more extreme and specialised 

 types of the Ophioglossaceae. The second paper, on two 

 synthetic genera of Filicales, dealt with some very interest- 

 ing problems of phylogeny. The two genera in question 

 are Plagiogyria (formerly included in Lomaria) and 

 Lophosoria (.usually grouped with .Alsophila). The author 

 not only put forward strong reasons why these respective 

 genera should be kept separate, but suggested that both 

 are probably important intermediate synthetic forms. 

 Thus he regards Plagiogyria as a transitional form related 

 on the one hand to the Gleicheniaceae and the Schizaeaceic, 

 and on the other to the whole series of Pterideae. 

 -Similarly in the case of Lophosoria, a probable sequence 

 may be traced from forms also having affinities with the 

 tjleicheniaceae through Lophosoria to .Alsophila and other 

 Cyatheaceze. 



Dr. Kidston and Prof. Gwynne-Vaughan described the 

 structure of the " false stems " of the fossil genus 

 lempskya. This plant had an extraordinarv habit. Its 

 erect " stem," which grew to a height of 9 or more feet. 

 kLj'^""*'*'^*''^ °^ ^" aggregate of branching stems 

 embedded m a compact mass of their own adventitious 

 roots. _ The individual stems were slender, and possessed 

 a dorsi-ventral symmetry. The authors think that in this 

 case the erect habit had been onlv recentlv acquired, the 

 particular method adopted being one which could be 

 NO. 2141, VOL. 85] 



evolved with great rapidity. They further suggest that the 

 erect habit of modern tree-ferns may be a secondary 

 character derived from Tempskya-like forms, in which the 

 original axis has developed at the expense of the lateral 

 branches. Dr. M. C. Stopes read a paper in which she 

 further described the fossil flower Cretovariutn japonicunt, 

 dealing especially with the structure of the ovary. Mrs. 

 Thoday, in a communication on the morphology- of the 

 ovule of Gnetum africanum, instituted a comparison 

 between this and the ovules of Welwitschia and Lageno- 

 stoma. She regards the ovule of Gnetum as probably 

 more primitive than that of Welwitschia on account of 

 its radial structure, the presence in the young ovule of a 

 well-developed pollen chamber, and the small develop- 

 ment of the free portion of the nucellus. Prof. F. \V. 

 Oliver next discussed the pollen chambers of various fossil 

 seeds. He showed that in certain seeds {e.g. Conostoma 

 spp.) the structure of the nucellar apex is much more 

 complex than in forms such as Lagenostoma, &c. In 

 these more complicated forms a second pollen chamber 

 was excavated below the primary one (which alone is 

 found in Lagenostoma). the latter becoming merely 

 vestigial. In the light of this discovery it seems possible 

 that the nucellar beak of Trigonocarpus, Ginkgo, &c.. 

 may represent a vestigial primary pollen chamber, which 

 had been functionally replaced by a more deeply seated 

 cavity. 



Prof. W. H. Lang concluded the afternoon's sitting 

 with a very interesting account of the morphology of the 

 stock of Isoetes. He produced evidence that the stock 

 grows regularly in two opposite directions. Leaves are 

 produced at the upper end, the stem apex being situated 

 at the base of a deep depression. Similarly, the roots 

 are borne in regular sequence on a downwardly growing 

 region. In this case, too, the apex is at the bottom of a 

 deep depression, but the growing point is obscured by the 

 congenital union of the sides of the depression. The 

 young roots are finally freed by the gradual and partial 

 separation of the united lobes of the stock. Although 

 greatly modified, the axis of Isoetes is strictly comparable 

 with that of Lepidodendron or Pleuromeia. 



The Semi-popular Lecture 

 this year was given by Prof. F. O. Bower, the subject 

 being " Sand-dunes and Golf Links." The lecture, which 

 was greatly appreciated, dealt chiefly with the part pl.ayed 

 by vegetation in the formation and fixing of sand-dunes. 

 Perhaps the prominence given to this part of the subject 

 caused some mild disappointment to the golfers present, 

 who wished for practical hints on the keeping of greens. 

 Prof. Bower showed a number of beautiful photographs, 

 amongst the most interesting being some of shifting 

 dunes. 



EXGIXEERIXG AXD CIVILISATIOX.' 

 T N ' order rightly to appreciate the share taken by our 

 ^ profession in bringing about the present state of 

 civilisation, a comparison should be made between the 

 conditions prevailing, say, in the Greek st.-ites during the 

 fifth and fourth centuries before Christ and those existing 

 now in the twentieth century after Christ. 



In indicating the state of knowledge at that period of 

 Greek history, it is enough to remind you that it was the 

 age of Themistocles, .Aristides, and Pericles, the states- 

 men ; of .^ischylus, Sophocles, Euripides, and Aristo- 

 phanes, the dramatists ; of Phidias, Scopas, and Praxiteles, 

 the sculptors ; of Apollodorus, Zeuxis, and Apelles, the 

 painters ; of Ictinus, the chief designer of the Parthenon, 

 and Dinocrates. who rebuilt the temple of Diana at 

 Ephesus and laid out the city of .Alexandria, the architects ; 

 of Herooofus, Thucydides, and Xenophon, the historians ; 

 of Socrates. Plato, and Aristotle, the philosophers. 



Can we say that there have been many since th.at time 

 who are worthy to be mentioned as equals of the men 

 I have just named? The fact alone that we use the 

 adjective " classical " to indicate perfection in literature 

 and art shows what a standing had been attained more 

 than 2000 years ago, and in many respects we feel down 



1 From the Presidential Ad1re?s delive-ed at th- Institution of Civil 

 Engineers on Xo\-ember i. by Mr. Alexander Siemens. 



