378 



NATURE 



[Stl'TEMBER 22, IQIO 



BIRD NOTES. 



'po tli.j July issue of the Quarterly Review Dr. H. Gadow 

 ■'• Luniniuiiicates an instructive article on tlie nature 

 and meaning of the colours of birds. After pointing out 

 the fallacy of the idea that the colouring of such birds as 

 the scarlet ibis or white egret can be in any sense pro- 

 tective, the author discusses the diverse means by which 

 colour is produced in birds, showing that while black and 

 the red and yellow group are pigmentary, blues and greens 

 are so-called structural tints, due to the reflection from 

 the surface of the feathers of an undue proportion of short 

 light-rays. Metallic colouring, which usually occurs in 

 black feathers, is due, of course, to another cause. Dr. 

 Gadow next proceeds to describe the sequence in which 

 various colours replace one another with the advance of 

 specialisation. As regards the cause of colour-specialisa- 

 tion, the author rejects both natural and se.xual selection, 

 remarking that if the latter were the inducing factor, every 

 gr' up and species would have its own taste, and each 

 individual would strive to develop its yellow patches into 

 orange and then into red. For the explanation offered in 

 place of natural and sexual selection, we must refer our 

 readers to the article itself. 



In the August number of W'itherby's British Birds the 

 editor congratulates his readers on the satisfactory response 

 which has been made this season to his appeal for assist- 

 ance in marking birds. Nearly ii,ooo rings were dis- 

 tributed, and schedules recording the marking of between 

 5000 and Oooo birds have been already received. The 

 cooperation is invoked of all into whose hands ringed 

 birds may fall. In the same issue Mr. W. Frohawk 

 describes and illustrates the feeding habits of the razor- 

 bill, remarking that all the specimens which have come 

 under his special notice fed on sand-launces. These fish, 

 to the number in some cases of so many as half a dozen 

 at a time, are held transversely in the beak, and the 

 marvel is how the bird manages to capture and hold one 

 after the other without losing those previously caught. 

 Possibly each is killed when caught ; but even then it is 

 difficult to see how the catch is procured and retained. 



To the August number of the Popular Science Monthly 

 Prof. F. H. Herrick contributes the third and final instal- 

 ment of an article on instinct and intelligence in birds. 

 It is concluded that many of the alleged cases of intelli- 

 gence are really due to habit, and that " all the intelli- 

 gence which birds may on occasion exhibit seems to give 

 way under the spell of any of the strange instincts. . . . 

 They seldom meet emergencies by doing the intelligent act, 

 and, in spite of the anecdotes, probably but seldom come 

 to the effective aid of their companions in distress. On 

 the other hand, I have more than once seen a mother bird 

 try to pluck a hair or piece of grass from the mouth of 

 a nestling." 



.Another instance of intelligence is afforded, in the 

 author's opinion, when a gull, after feeding its young for 

 three weeks on partially digested fish, offers them entire 

 squids to swallow. The practice displayed by young king- 

 fishers of arranging themselves in a row and showing 

 a tendency to walk backwards is, however, attributed to 

 fiabit formed underground ; while the time it takes for 

 hole-nesting birds to change their place of entrance when 

 a more convenient access has been afforded is an instance 

 of the dominance of habit over intelligence. 



rilE BRITISH ASSOCIATION AT SHEFFIELD. 



ZOOLOGY. 



Opening .\ddress by Prof. G. C. Bourne, M..\., D.Sc, 



F.R.S., President of the Section. 



In choosing a subject for the address with which it is 



my duty, as President of this Section, to trouble you, I 



have found myself in no small embarrassment. As one 



whose business it is to lecture and give instruction in the 



details of comparative anatomy, and whose published work, 



tiualectinque sit, has been indited on typicaT and, as men 



would now say, old-fashioned morphological lines, I seem 



lo stand self-condemned as a niorphologist. For morpho- 



*o.L^\ , if I read the signs of the times aright, is no longer 



NO. 2134, VOL. 84] 



in favour in this country, and among a sectioti of the 

 zoological world has almost fallen into disgrace. At all 

 events, I have been very frankly assured that this is the 

 case by a large proportion of the young gentlemen whom 

 it has been my fate to examine during the past two years ; 

 and, as this seems to be the opinion of the rising genera- 

 tion of English zoologists, and as there are evident signs 

 that their opinion is backed by an influential section of 

 their elders, I have thought that it might be of some 

 interest, and perhaps of some use, if I took this oppor- 

 tunity of offering an apology for animal morphology. 



It is a sound rule to begin with a definition of terms, so 

 I will first try to give a short answer to the question 

 "What is morphology?" and, when I have given a 

 somewhat dogmatic answer, I will try to deal in the course 

 of this address with two further questions : What has 

 morphology done for zoological science in the past? What 

 remains for morphology to do in the future? 



To begin with, then, what do we include under the term 

 morphology? I must, first of all, protest against the 

 frequent assumption that we are bound by the definitions 

 of C. F. Wolff or Goethe, or even of Hacckel, and that we 

 may not enlarge the limits of morphological study beyond 

 those laid down by the fathers of this branch of our science. 

 We are not — at all events we should not be — bound by 

 authority, and we owe no allegiance other than what reason 

 commends to causes and principles enunciated by our pre- 

 decessors, however eminent they may have been. 



The term morphology, stripped of all the theoretical con- 

 ceptions that have clustered around it, means nothing 

 more than the study of form, and it is applicable to all 

 branches of zoology in which the relationships of animals 

 are determined by reference to their form and structure. 

 Morphology, therefore, extends its sway not only over the 

 comparative anatomy of adult and recent animals, but also 

 over palaeontology, comparative embryology, systematic 

 zoology and cytology, for all these branches of our science 

 are occupied with the study of form. And in treating of 

 form they have all, since the acceptance of the doctrine of 

 descent with modification, made use of the same guiding 

 principle — namely, that likeness of form is the index to 

 blood-relationship. It was the introduction of this prin- 

 ciple that revolutionised the methods of morphology fifty 

 years ago, and stimulated that vast output of morpho- 

 logical work which some persons, erroneously as I think, 

 regard as a departure from the line of progress indicated bv 

 Darwin. 



We may now ask, what has morphology done for the 

 advancement of zoological science since the publication of 

 the " Origin of Species "? We need not stop to inquire 

 what facts it has accumulated : it is sufficiently obvious 

 that it has added enormously to our stock of concrete 

 knowledge. We have rather to ask what great general 

 principles has it established on so secure a basis that they 

 meet with universal acceptance at the hands of competent 

 zoologists ? 



It has doubtless been the object of morphology during the 

 past half-century to illustrate and confirm the Darwinian 

 theory. How far has it been successful? To answer this 

 question we have to be sure of what we mean when we 

 speak of the Darwinian theory. I think that we mean at 

 least two things. (1) That the assemblage of animal forms 

 as we now see them, with all their diversities of form, 

 habit, and structure, is directly descended from a precedent 

 and somewhat different assemblage, and these in turn from 

 a precedent and more different assemblage, and so on down 

 to remote periods of geological time. Further, that 

 throughout all these periods inheritance combined with 

 changeability of structure have been the factors operative in 

 producing the differences between the successive assem- 

 blages. (2) That the modifications of form which this 

 theory of evolution implies have been rejected or preserved 

 and accumulated by the action of natural selection. 



As regards the first of these propositions, I think there 

 can be no doubt that morphology has done great service in 

 establishing our belief on a secure basis. The transmuta- 

 tion of animal forms in past time cannot be proved 

 directly ; it can only be shown that, as a theory, it has a 

 much higher degree of probability than anj other that car 

 be brought forward, and in order to establish the highest 

 possible degree of probability, it was necessary to demon- 

 strate that all anatomical, embryological, and palironto- 



