550 



NATURE 



[December 23, 1920 



for the development of the subject of human 

 physioloj<y. He pointed out the importance of a 

 knowledge of physiology for rational medicine, but 

 contended that it would be of greater value if more 

 use were made of the human subject for illustrating 

 the facts of physiology. The use of methods 

 of examination applicable to the human subject 

 should be extended, but, of course, the methods 

 must be controlled by experiments on animals. 

 Dr. Lewis finished his paper by appealing to the 

 citizens of South Wales for an endowment for the 

 department of physiology. As a graduate from South 

 Wales, he felt the handicap due to lack of accom- 

 modation and of equipment; now that a good build- 

 ing had been provided he hoped that sufficient money 

 would be forthcoming for its equipment and upkeep. 



As a good example of the way in which animal 

 experiments must be used to elucidate the physiology 

 of the human subject Dr. Lewis's paper on "Auri- 

 cular Flutter" may be quoted. This was a descrip- 

 tion of experiments on the heart of the dog. The 

 time-relations of electrical changes in the auricle were 

 traced, and they were found to differ from those of 

 the auricle beating in its natural way. The evidence 

 from the time-relations of the electrical changes 

 points to a wave of contraction passing round the 

 superior and inferior venae cava. The normal beat 

 consists of a contraction wave which spreads over 

 the whole auricle, but in auricular flutter the wave 

 travels down 'one side of the auricle round the inferior 

 vena cava, and returns by the other side of the 

 auricle to the superior vena cava. This establishes a 

 circus movement which continues indefinitely. The 

 wave of excitation reaches each part of the auricle at 

 a sufTicient interval after the previous contraction 

 to fall outside the refractory period ; hence the 

 series of quickly following circus movements. The 

 normal contraction ends because the wave of con- 

 traction spreads fan-like over the whole auricle, 

 when it reaches the limits of the auricle : it ceases 

 because the wave of excitation is dammed by the 

 refractory period of the contracting auricle. 



Miss E. Bedale, in collaboration with others, read 

 a paper on "The Energy Requirements of School- 

 children." The measurement of energy was at- 

 tempted in two ways. The first consisted in obtain- 

 ing diet-sheets prepared by the pupils on which th€y 

 recorded the weighed amounts of the various food 

 materials eaten. These diets were evaluated by 

 analytical data, and the energy-value of the diet was 

 obtained in that way. The second method was to 

 measure the energy expenditure by means of the respira- 

 tory exchange. The basal metabolism was measured 

 during sleep. Measurements of the respiratory 



exchange were made during various forms of activity 

 and the daily expenditure was estimated by a cal- 

 ( ulation involving the amount of time occupied in the 

 diilcrent forms ot activity. The two energy values did 

 not agree, the intake of energy being greater than the 

 expenditure. It was left an open question as to how 

 much of the lack of agreement was due to errors in 

 computing the energy output in the various forms of 

 activity during the day. 



Prof. Waller gave some figures on an allied subject 

 in which he measured the energy expenditure by the 

 output of carbon dioxide. He contrasted a man in 

 training with an untrained man running the same 

 distance at the same speed. Assuming that tfie basal 

 metabolism of the two men was the same, the un- 

 trained man expended double the amount of energy 

 in doing the same work. 



Prof. Herring recorded measurements showing the 

 effect of pregnancy on the various organs of 

 the white rat. The animals were from a standard 

 litter, and kept under identical conditions except for 

 the occurrence of pregnancy in some of them. Most 

 of the organs showed a slight decrease in weight ; 

 the only ones that showed an increase in weight 

 were the liver and the adrenals. The increase in the 

 former shows the great importance of metabolism 

 during pregnancy. The increase in the latter is 

 probably in the cortex, and not in the medulla. 



Dr. Edridge-Green read a f)aper on "The Preven- 

 tion of Myopia," in which he stated that the exciting 

 cause of myopia is an increase in intra-ocular pres- 

 sure. Games such as cricket, football, golf, etc., do 

 not cause myopia, but severe strains such as lifting 

 heavy weights, especially with the eyes pointing down- 

 wards, should be avoided. 



Prof. Waller recorded some further observations on 

 "The Emotive Response of the Human Subject." 

 The response is usually confined to the hand and 

 foot, but a few individuals show it on the forearm 

 and leg. The reaction appears first on the hand {2') 

 and then on the foot (3"). H it occurs elsewhere it 

 is ^slaved as long on the arm as on the foot (3'), 

 and shows a longer latent interval on the leg (4"). 



Prof. Waller presented the report of the Committee 

 on Electromotive Phenomena in Plants. The zone of 

 growth in iris is at the base of the leaf, and in 

 anemone at the apex of the plant. When an induc- 

 tion shock is passed through an active growing tissue 

 the resultant electrical change is always from the 

 more active to the less active portion in the plant- 

 tissue, no matter in which direction the stimulating 

 current is passed. In dead tissues the current pro- 

 duced after stimulation is small, and always in the 

 direction of polarisation. 



Botany at the British Association 



THE diversified character of modern botany was 

 well exemplified in the programme of the 

 Cardiff meeting, and the rapprochement of the 

 sciences was evidenced by the three joint discussions 

 in which the Section took part. Joint sittings have 

 become an important feature ,of recent years, and in 

 this reflect the tendency of modern research to over- 

 step the necessarily arbitrary boundaries of the so- 

 called sciences and to combine with other workers on 

 the border-line problems. 



Thus it is not surprising to find botanists co- 

 operating with zoologists and geologists to consider 

 whether Mendelian work and palseontological evi- 

 dence show as yet any sign of giving mutual support 

 to the conclusions derived from each line in- 

 dependently. 



The joint discussion with the physiologists and 

 chemists entitled " Biochemistry and Svstematic 

 Relationships," presided over by Miss Saunders, 

 president of the Botany Section, aimed at con- 



sidering whether the present state of knowledge 

 indicates any definite ratio between biochemical con- 

 stitution and morphological expression — that is to 

 say, does biochemical investigation show a chemical 

 relationship in the forms which have long been 

 grouped together on morphological grounds? The dis- 

 cussion was introduced by a paper by the Hon. 

 Mrs. Onslow, wherein the possibility of expressing 

 reproductive and vegetative characters in chemical 

 terms was explored ; lines of plant-metabolism were 

 considered and suggestions made as to correlations 

 between the evolution of the families of flowering 

 plants and the presence of oxygenases, and the dis- 

 tribution of anthocyan pigments and of flavones was 

 discussed. The papers and open discussion which 

 followed indicated the importance of the new line of 

 work, inasmuch as a considerable correspondence of 

 chemical and morphological relationship had been 

 established, but laid stress also on the necessity for 

 extreme carefulness in its application in view of the 



