October 9, 1890] 



NATURE 



579 



Mr. F. T. Trouton read a paper advocating the introduction 

 of a coefficient of abrasion as an absolute measure of hardness. 



Mr. F. H. Varley exhibited and explained the action of a 

 new direct-reading photometer — an ingenious and compact in- 

 strument, in which intermittent illumination is employed for 

 equalizing the intensity of illumination from two sources of 

 light. 



BIOLOGY AT THE BRITISH ASSOCIATION. 



A LTIIOUGH the number of papers in Section D was not 

 -'*■ quite so large as usual, it was found sufficient to occupy 

 the time fully. As on previous occasions, the most attractive 

 part of the proceedings was a discussion on a subject of general 

 interest arranged beforehand, and opened by set papers. 



After the President's address on Thursday, Prof. Newton 

 gave an interesting account of the ornithology of the Sandwich 

 islands, discussing its peculiarities and probable affinities. He 

 showed that the fauna is now undergoing modification, and is in 

 danger of extermination on account of the changes which are 

 rapidly being made in the vegetation of the islands ; and he 

 urged strongly the necessity of making a thorough examination 

 of the fauna and flora of this important region while it is still 

 possible. This paper led to the appointment of a committee, 

 with a grant, for the purpose of seeing that the necessary ex- 

 ploration was carried out at once. 



The usual reports on the zoology and botany of the West 

 India Islands, on the migration of birds, on the disappearance 

 of native plants, on a deep-sea tow-net, on the Botanical Station 

 at Peradeniya, Ceylon, on the Biological Laboratory at Plymouth, 

 and on the Zoological Station at Naples, were read, and the 

 committees were reappointed. 



The greater part of Friday's meeting was occupied by an 

 important and interesting discussion on the teaching of botany, 

 and especially the teaching in schools or to the young. The 

 subject was opened with papers by Prof. Marshall Ward, 

 Prof. F. W. Oliver, and Prof. F. O. Bower. Prof. Marshall 

 Ward discussed the teaching of botany under the three heads : 

 (i) elementary or school teaching ; (2) more advanced or 

 academic teaching ; and (3) applied or special botany, such as 

 forestry. He urged strongly the advantages of an early training 

 in botany, and showed the suitability of the subject for school 

 teaching, not however from books, but practically, and especially 

 by means of field-work. In the teaching of applied botany he 

 considered that principles and generalizations were of more 

 importance than masses of facts, even in the training of the so- 

 called practical man. 



Prof. Oliver treated chiefly of the teaching of elementary 

 botany to medical students at our colleges ; and Prof. Bower 

 dealt also with the arrangement of the usual junior University 

 course, which he considered should be wide in its range and 

 suggestive, rather than more restricted and exhaustive. 



A number of other teachers of botany joined in the discussion ; 

 and Dr. Forsyth, of the Leeds Highef Grade School, showed 

 that many of the suggestions which had been made were being 

 carried out at his school, where the pupils were taken periodi- 

 cally to the fields to collect the specimens for their object 

 lessons. 



Prof. Marsh then gave an interesting account of the Cre- 

 taceous mammals of North America, of which he had now in 

 his possession over 1000 specimens, all obtained during the last 

 year or so. These remains all appear to belong to the lower 

 forms of Mammalia, such as Monotremes and Marsupials, and 

 are all of small size, although they are found in the same beds 

 with the gigantic Dinosaurs, such as Triceratopt. 



Prof. Denny gave an account of an abnormality which he had 

 found in three successive seasons in some flowers of Tropaolutn, 

 and which consisted in the inversion and in some cases duplica- 

 tion of the spur. Prof. Denny suggested that these abnormal 

 flowers seeemed to indicate that the spur was really the repre- 

 sentative of the two missing stamens. 



Canon Tristram contributed some notes on the natural history 

 of Hierro and Graciosa, two outlying islands of the Canary 

 Group. A paper by Mr. E. H. Hankin dealt with the modi- 

 fying action of ferments, such as trypsin and pepsin, upon 

 diseases caused by bacteria, e.g. anthrax. It is suggested that 

 the injection of the ferment causes a "defensive proteid " to be 

 formed and thrown into the circulation for the purpose of killing 

 the bacteria. 



On Monday, Prof. Miall and Mr. Hammond gave an account 

 of the development of the head of the adult fly in the life-history 

 of the dipterous insect Chironomus, commonly found in impure 

 water. Prof. Marshall and Mr. Bles called attention to varia- 

 bility in development amongst allied animals, and even amongst 

 individuals of the same species. Dr. P. H. Carpenter contributed 

 notes on the anatomy and morphology of the Cystidea. 



Mr. S. F. Harmer discussed the regeneration of lost parts 

 in the Polyzoa, including the formation of new polypites in 

 Pedicellina on the tips of the old stalks where no endodermal 

 tissues are present. Dr. S. J. Hickson gave two papers on 

 the Hydrocorallina — the one dealing with the meaning of the 

 ampullae in Millepora viurrayi, which were found to contain 

 modified daciylozooids bearing only very large sperm sacs ; and 

 the other being on the gonangia of Distichopora and Allopora. 

 An important conclusion drawn from these investigations was 

 that, as regards the position and character of the gonads, Mille- 

 pora is not related to any of the Stylasteridae. 



Amongst a number of botanical papers read on Tuesday 

 were : one by Mr. R. Warrington, showing that certain bacteria 

 have the power, usually supposed to be peculiar to chlorophyll- 

 bearing organisms, of forming organic compounds from inorganic 

 materials; one by Prof. Bower, on the phylogenetic relation- 

 ships between the diff"erent groups of Ferns ; one by Prof. P. 

 Geddes, on the origin of protandry and protogyny ; and one by 

 Dr. J. M. Macfarlane, on hybrids, in which it was shown from 

 a number of genera of plants that certain hybrids which had 

 been produced were intermediate, not only in appearance and 

 general structure, but even in the most minute histological 

 details, between the two parent species. 



GEOGRAPHY A T THE BRITISH 

 ASSOCIATION. 



TN the quality and scientific value of the papers, this Sectioi> 

 -'• was considerably above the average of last year. There 

 were only about a score of papers altogether, but the Organizing 

 Committee had determined rather to'be short of papers than to 

 accept any of trivial importance. As it was, the time of the 

 Section during the four days on which it met was well filled up. 

 The sittings were well attended, and sometimes almost crowded ; 

 which is saying much, considering the size of the hall in which 

 the Section met. The Section adopted a plan which answered 

 admirably. It adjourned each day from i to 2 p.m., and 

 invariably a good audience assembled for the afternoon meeting. 

 The hall was well filled at the President's address, which was 

 an excellent resumi of the physical geography of the Mediterra- 

 nean and the regions around its shores. On two other occasions 

 the lower part of the hall was quite filled by audiences evidently 

 greatly interested. First, on the Monday, when there was a 

 joint meeting of Sections E and F to discuss the important sub- 

 ject of the Lands of the Globe still available for European Settle- 

 ment. Mr. E. G. Ravenstein opened the conference with a paper 

 giving what may be called the geography of the subject. He ex- 

 cluded from consideration the Polar areas, desert areas, and tropica) 

 areas unsuited to a European population. He showed that, dealing 

 with the subject from a purely theoretical point of view, the popu- 

 lation of the world, at the present rate of increase, would, in about 

 three or four generations, amount to something like 5000 millions. 

 This, of course, sounds very alarming, but as in the case of the 

 prediction of the exhaustion of our coal supply, it was shown 

 during the discussion that we may keep our minds at ease. Prof. 

 Marshall, Sir Rawson Rawson, Dr. Cunninghame, Mr. Bourne, 

 and others who took part in the subsequent discussion, mainly 

 from the economical point of view, suggested various considera- 

 tions in modification of those derived from the purely theoreti- 

 cal standpoint. The earth has still vast undeveloped resources ; 

 a more equable distribution of these among mankind is possible, 

 and even desirable ; the theoretical rate of increase will cer- 

 tainly be modified in various ways ; the so-called deserts may, 

 actual experiment has shown, be made, by means of irrigation 

 from underground supplies, both fertile and habitable. The 

 great truth which came clearly out of the discussion — a truth 

 which ought to be widely realized now that tropical Africa is 

 being opened up — is that European colonization, in the proper 

 sense of the term, is impossible, so far as present ' experience 

 goes, between the tropics. There are, no doubt, modifying 

 circumstances in some cases, but these are rare. As usual in 

 such discussions, there was a certain amount of irrelevant talk >. 



NO. 1093, VOL. 42] 



