March 23, 1922] 



NA TURE 



373 



Letters to the Editor. 



{The Editor does not hold himself responsible for 

 opinions expressed by his correspondents. Neither 

 can he undertake to return^ or to correspond with 

 the writers of rejected manuscripts intended for 

 this or any other part of NATURE. No notice is 

 taken of anonymous commttnications.^ 



Research Degrees and the University of London. 



The question of research degrees in the University 

 of London, which is the subject of a letter by Dr. 

 Morley Davies in Nature of February 23, p. 238, 

 raises an important matter of principle. The 

 proposal of the sub-committee of the Academic 

 Council of the University to institute a new series 

 of examinations for the M.Sc. degree, appears to 

 have arisen from a desire to secure uniformity in 

 the granting of the degree. Whether it will do so 

 or not is a matter of opinion, but, in any case, many 

 people consider that such uniformity can be obtained 

 only by retrogressive steps, in view of the urgent 

 necessity for the training of research workers. 



The examination fever has fortunately died 

 down in recent years. The general raising of the 

 standard of examinations which has accompanied 

 the rapid advances in natural and experimental 

 science has resulted in the Honours B.Sc. Examina- 

 tion becoming not only a searching test of the general 

 knowledge of the principal subject chosen by the 

 candidate, but a severe test of his familiarity with 

 some special branch. Beyond the standard thus set, 

 it is very difficult for an examiner to impose a test 

 without giving a candidate a choice of a large number 

 of highly technical questions either limited in scope 

 or controversial because of the generahties in wliich 

 they tempt candidates to indulge. Such a type of 

 examination almost puts the examiner at the mercy 

 of an examinee who has the wit to ask in an apos- 

 trophic way, " What did Gladstone say in 1876 ? " 

 or to refer to the rocks of the Amazonian forests or 

 the flora of the Senussi country ! 



Ostensibly, the undesirab'ility of having four 

 standards of research for the B.Sc. (research), M.Sc, 

 Ph.D., and D.Sc. disturbs the sub-committee. Dr. 

 Davies has dealt effectively with this question. 

 Leaving aside the B.Sc. by research as a qualification 

 granted but rarely and exceptionally, no difficulty 

 as regards the standard for the other three degrees 

 will arise in the mind of many examiners. 



May I submit the following as a purely suggestive 



general scheme of minimum requirements ? The 



candidate should in his M.Sc. thesis show that he is 



familiar with the literature of his branch of research, 



and able to summarise and analyse that hterature 



effectively ; further, that he has had sufticient 



originaUty of mind to pursue a line of inquiry 



instituted by others, and to extend knowledge in 



such a direction. For the Ph.D. degree he should 



be able to make a marked contribution to the advance 



of knowledge, and to submit a finished account of 



an investigation or an interim report, complete so far 



Li>is possible, and containing legitimate deductions, 



lis dissertation bearing evidence of the expenditure 



>f an appropriate amount of time and labour. For 



le degree of D.Sc, it is desirable that the candidate 



lould display great originality of mind and a 



ipacity for research of a high order. He should be 



ible not merely to use the methods and weapons 



)f others, to extend their fields of investigation and 



ipply their results, but to evolve methods and tools 



jf his own, strike out into new paths, and in turn 



'give a lead to less experienced workers. 



If some such distinction as that drawn above is 

 not, even unconsciously, adopted, the matter of the 

 respective standards for the Ph.D. and D.Sc. is likely 

 to become chaotic. If the M.Sc. by examination is in- 



NO. 2734, VOL. 109] 



stituted an undesirable tendency, already in evidence, 

 for the candidate to proceed direct from B.Sc. to 

 Ph.D. (and there remain) will undoubtedly develop. 



As an illustration of an opposite point of view to 

 that taken by the sub-committee, I may perhaps be 

 allowed, without advocating in any way too early 

 speciaUsation, to commend the scheme adopted in 

 this university of allowing a student (by arrangement 

 of the head of the department concerned) to present, 

 as an alternative to taking one special paper in 

 the Hons. B.Sc. Examination, a report upon some 

 piece of investigation carried out by him. 



P. G. H. BOSWELL. 



University of Liverpool, March 7, 1922. 



Phenological Observations. 



The highly interesting communication of Mr. J. E. 

 Clark in Nature of February 16 directs attention to 

 some important problems in phenology, and I beg 

 space to indicate one or two that have more especially 

 occurred to me. 



First, in the comparison between England S.E. 

 and England S.W., I do not think the earlier flowering 

 of horse-chestnut {Msctilus hipp.) around London than 

 in Cornwall is at all a surprising result, inasmuch as 

 the climate of Cornwall with its rough sea gales is 

 notoriously unfavourable to trees (except, perhaps, 

 in the deeper valleys) as distinct from herbaceous 

 plants. It may also be that the more rapid rise of 

 temperature in the south-east of England than in 

 the oceanic south-west peninsula acts as a stimulus 

 to the spring flowering of certain trees. 



Secondly, I am anxious to urge the desirability 

 of coiTelating the autumnal phases with the spring 

 phases of vegetation in studying the effects of 

 chmatic conditions upon the seasonal phenomena of 

 plants. Let me illustrate the point by an example, 

 that of our native oak {Quercus robur). According 

 to Hopkins's " bio-cUmatic " law, the oak should 

 burst into leaf and flower a week to ten days sooner 

 in southern than in northern England, and this 

 certainly agrees pretty well with general experience- 

 But is it safe, therefore, to infer that because the 

 oak puts forth its leaves a week or so earUer in the 

 south of England in response to a warmer cUmate, it 

 will shed them a week later in response to the same ? 

 Consider the opposing factors that appear to be at 

 work. In studying individual oaks of the same locality 

 in diverse parts of the country I have constantly 

 noticed that those trees in autumn which are in full 

 tint, or are half bare, are usually such as have already 

 ripened their acorns, whereas those of which the 

 leaves are still green have not yet matured the acorns. 



Now if one may apply this generalisation to the 

 comparison between the north and south of England 

 it would appear that, on the one hand, colder climatic 

 conditions will tend to cause earlier defoliation in the 

 north, and, on the other hand, that internal biological 

 conditions will tend to delay defoliation in order that 

 the acorns, the flowersof which were tendays behind the 

 south to commence with, may be brought to maturity. 

 But the generally more inclement conditions in the 

 north, with the earlier night frosts, are impatient of 

 any delay in the fall of the leaf, and it becomes a 

 question of the utinost interest how the average dates 

 of defoliation in the north and south of England 

 actually do compare with those of foliation. One 

 knows tliat the northern limit of the British oak as 

 a flourishing species is set somewhere about the 

 middle of Scotland, and presumably the critical 

 determining fact is a summer too cold and short for 

 fructification. 



Thirdly, in the complex study of phenology the 

 influence of factors other than meteorological should 

 ever be borne in mind, as was brought to the attention 

 of the Royal Meteorological Society last year by 



