484 



NATURE 



[April 22,, 1874 



being in the deep soundings between the islands of St. Thomas 

 and Ste. Croix. 



During the same day two other slight shocks, one at about 

 10 A. M. the other at noon, were felt at St. Thomas ; they were 

 unaccompanied ty noise. W. G. Palgrave 



St. Thomas, W.I., March 21 



Physical Axioms 



Convinced that the fulfilment of astronomic predictions can 

 never demonstrate the laws of motion, and yet feeling myself 

 quite destitute of intuitive belief in those laws, I have been led 

 to think that in the present controversy truth may lie somewhere 

 between the positions respectively enunciated by Mr. Spn:er 

 and his critic. 



By reasoning which seems to me equally lucid, ingenious, 

 and unanswerable, Mr. Spencer has shcin that certain 

 ultimate mechanical laws are tacitly assumed in every process 

 of experimental verification. But I do not see that this 

 vitiates completely the inference drawn from such verifications. 

 The pure empiricists argue that because certain observed 

 results coincide with the results of calculation, therefore the 

 assumptionson which the calculation was based must be true. Now 

 without doubt the demonstrative character of this inference 

 vanishes entirely under Mr. Spencer's searching criticism. But 

 it seems to me that a high probability remains behind. For 

 were there any but an excessively minute error in the laws of 

 motion, our astronomical observations could agree with the 

 results of calculation only by a conflict of errors — a conflict which 

 Mr. Spencer himself hints at. But there are overwhelming 

 chances that these errors would not be so accurately adjusted 

 throughout an immense variety of cases as exactly to compensate 

 one another in every single instance. Hence I cannot but regard 

 the laws of motion as hypotheses, the truth of which is shown by 

 experiment to be overwhelmingly probable. The (lo:lrine here 

 assumed may be illustrated by an appeal to those old friends of 

 probability students — the dice. If I throw double sixes ten times 

 running I naturally conclude that the dice are loaded. This 

 supposition almost necessarily involves the sameness of the ten 

 throws, whereas the supposition that they were not loided is 

 consistent with an immense number of other results. Our minds 

 choose the former alternative in obedience to an instinct which 

 might with much show of propriety be formulated into an axiom. 

 We may, however, deduce a ju tification for it from two ultimate 

 intuitions of our nature — belief in uniformity of sequence and the 

 general doctrine of chances — intuitions by which the mind 

 apprehends respectively the ultimate law of knowledge and the 

 ultimate law of ignorance. Belief in any special fact beyond 

 individual experience can be rationally arrived at only by 

 applying the former law to that knowledge which our individual 

 experience furnishes, and the latter law to that ignorance which 

 our individual experience has failed to enlighten. 



It is \\i^ approximate \xa,i.\i of the laws of motion to which Ihave 

 throughout referred. That there may be an excessively minute 

 error in all physical and even all geometrical principles. Prof. 

 Clifford has long ago shown how unphilosophical it is to deny. 

 ¥. W. Frank LAND 



Royal College of Chemistry, April iS 



The Fertilisation of Fumariaceae 

 Apropos of the interesting discussion on this subject which 

 has appeared in your columns, I should much like to know 

 \\'helher any of your readers have observed the mode of fertilisa- 

 tion in Corydalis claviciilata. Last summer I spent a consider- 

 able time in attempting to find this out, but without success. 

 In every flower which I gathered in the mature state, I found 

 the style broken off at the articulation immediately above the 

 ovjry, as if to prevent the possibility of fertilisation after a 

 certain period. As the interior parts are completely concealed 

 by the corolla, it was difficult to determine whether the separa- 

 tion had actually taken place on the flower, or was the result of 

 the dissection, but I believe the former to be the case. In a 

 large number of obtervations, extending over a considerable time, 

 I never saw an insect visit the plant (this «asin Westmoreland), 

 though seeds were freely produced. MiiUer does not mention 

 this species in his classical work on the subject, " Die Befruchiung 

 der Dlumen durch Insekten." Ali-red W. BE.NiN'ETT 



Allow me to bring before the notice of readers of Nature 

 a small point bearing on the fact of the bright hue presented, 

 after lertilisation, by the flowers of Funiaria capreohita. 



Is it not possible that the pile colour may be more attractive 



to the fertilising insects than a brighter one would be ? May 

 not the drawing-principle be the result of correlation between the 

 art-manifesiations of the attracting and the resthetic suscepti- 

 bilities of the attracted organism, and not depend solely on 

 gaudiness of the flower? If this be so. we know that these sus- 

 ceptibilities have, at any rate sometimes, a very limited range, as 

 is seen in the bee-orchis, where the similarity of the labellum to 

 the body of a bee is very close, both in colour and in form, and 

 cannot be useless, seeing that a great amount of developmental 

 force is expended in its production. On this view also the rejec- 

 tion of highly-coloured poisonous caterpillars may in part be re- 

 ferred to the non-agreement of their hues with the orthodox 

 colour-notions of birds. On the other hand, if mere gaudiness 

 is aimed at, why should there be such diversity exhibited.? why 

 would not one colour answer the purpose in every instance ? 



The present case is capable of ready explanation on the sup- 

 position that it comes under the influence of natural selection ; 

 for, as Mr. Spencer has shown, the hue of the flower results from 

 a diminished amount of nutritive material supplied to the 

 coloured parts, so that the least vigorous individuals would have 

 these most highly coloured at the time of fertilisation. But 

 since the ]iale flowers are preferred by the insects, they would 

 stand a better chance of being fertilised than would the bright 

 ones, so that a process of selection would be set up resulting ul- 

 timately in the disappearance of the latter. 



If it be established that cross fertilisation is not the rule with 

 the flowers of this fumitory, of course it is a fact which has 

 nothing whatever to do with the present argument, and the ex- 

 planation given by Messrs. Darwin and MiiUer is entirely satis- 

 factory. 1 cannot but think, however, that special attention will 

 bring to light many cases of cross-fertilised flowers becoming 

 more highly coloured after fertilisation, the phenomenon being 

 explained simply as a decomposition-phase in the life-history of 

 the contents of the cells composing the coloured organs. 



S. MooRE 



I V£nti;re to suggest the following as possibly an explana- 

 tion of the fact observed by Mr. Traherne Moggridge, that the 

 flowers oi Fumaria pallidijlora attain their brightest colouring 

 when the time for their fertilisation has past. 



In plants with a racemose inflorescence the individual flowers 

 do not open simuhaneuusly, but more or less in succession. 

 The flowers lowest in the raceme open first : by the time they 

 have in Fumaria pallidijio} a attained their brighter colour, those 

 a little higher up on the rachis are just at the stage for fertilisa- 

 tion, and the former may serve to aUract insects to the latter, 

 just as in some plants [e.g. Poinsettia) we may presume that the 

 highly-coloured bracts attract insects to the comparatively incon- 

 spicuous flowers which they surround. The flowers a little way 

 up the raceme would serve in their turn to attract insects to those 

 above them ; and these again to those still higher ; the process 

 going on for a considerable time in Fumaria, as it is quite 

 common for the pedicels in the lower part of a raceme to be 

 bearing fruit that has attained its full size, while at the top there 

 are flower-buds still unopen. 



Quisqualis indica afl'ords another instance of flowers assuming 

 a more intense colour after fertilisation. Its flowers grow in 

 short spikes ; on first opening and during fertilisation, are 

 white, very faintly tinged with pink; but subsequently turn a 

 light reddish-orange, and finally a purplish-red. T. Comber 



Newton-le-WiUows, April 7 



Power of Memory in Bees 



Illustrations drawn from experiments or observations made 

 upon animals lower than ourselves in the scale of life must always 

 possess great interest. That impressions received by us in early 

 life are more permanent than those made in after years, and that 

 the memory of the old is less retentive in 'he reception of new 

 impressions than is that of children, are circumstances universally 

 acknowledged. On October 29, 1S73, I removed a hive of bees 

 in my garden, after it was quite dark, for a distance of 12 yards 

 from the place in which it had stood for several months ; and 

 between its original situation and the new one there was a bushy . 

 evergreen tree, so that all si.ht of its former place was ob- 

 structed to a person looking from the new situation of the 

 hive. 



Notwithstanding this change, the bees, every day, flew to the 

 locality where they formerly lived, and continued flying around 

 the site of what had been their home, until, as night came on, 

 they many of them sank upon the grass exhausted and chilled by 

 the cold. Numbers, however, returned alive to their new position, 



