crest like the topaz, while in another

it resembles the sapphire, The more vivid colours and more developed plumage of the males, I am now inclined to think may be wholly due to their greater vital energy, and to those general laws which lead to such superior developments even in domestic breeds; but in some cases the need of protection by the female while incubating, to which I formerly imputed the whole phenomenon, may have suppressed a portion of the ornament which she would otherwise have attained.

Another real, though as yet inexplicable cause of diversity of colour, is to be found in the influence of locality. It is observed that species of totally distinct groups are coloured alike in one district, while in another district the allied species all undergo the same change of colour. Cases of this kind have been adduced by Mr. Bates, by Mr. Darwin, and by myself, and I have collected all the more curious and important examples in my Address to the Biological Section of the British Association at Glasgow in 1876. The most probable cause for these simultaneous variations would seem to be the presence of peculiar elements or chemical compounds in the soil, the water, or the atmosphere, or of special organic substances in the vegetation; and a wide field is thus offered for chemical investigation in connection with this interesting subject.

Yet, however we may explain it, the fact remains of the same vivid colours in definite patterns being produced in quite unrelated groups, which only agree, so far as we yet know, in inhabiting the same locality.

Let us now sum up the conclusion at which we have arrived, as to the various modes in which colour is produced or modified in the animal kingdom.

The various causes of colour in the animal world are, molecular and chemical change of the substance of their integuments, or the action on it of heat, light or moisture. It is also

produced by interference of light in superposed transparent lamellæ, or by excessively fine surface striæ. These elementary conditions for the production of colour are found everywhere in the surface-structures of animals, so that its presence must be looked upon as normal, its absence as exceptional.

Colours are fixed or modified in animals by natural selection for various purposes; obscure or imitative colours for concealment-gaudy colours as a warning-and special markings, either for easy recognition by strayed individuals, females, or young, or to direct attack from a vital part, as in the large brilliantly-marked wings of some butterflies and moths.

Colours are produced or intensified by processes of development, either where the integument or its appendages undergo great extension or modification, or where there is a surplus of vital energy, as in male animals generally, and more especially at the breeding-season.

Colours are also more or less influenced by a variety of causes, such as the nature of the food, the photographic action of light, and also by some unknown local action probably dependent on chemical peculiarities in the soil or vegetation.

These various causes have acted and reacted in a variety of ways, and have been modified by conditions dependent on age or on sex, on competition with new forms, or on geographical or climatic changes. In so complex a subject, for which experiment and systematic inquiry has done so little, we cannot expect to explain every individual case, or solve every difficulty; but it is believed that all the great features of animal coloration and many of the details become explicable on the principles we have endeavoured to lay down.

It will perhaps be considered presumptuous to put forth this sketch of the subject of colour in animals, as a substitute for one of Mr. Darwin's most highly elaborated theories-that of voluntary or perceptive sexual selec

tion; yet I venture to think that it is more in accordance with the whole of the facts, and with the theory of natural selection itself; and I would ask such of my readers as may be sufficiently interested in the subject, to read again chapters xi. to xvi. of the Descent of Man, and consider the whole theory from the point of view here laid down. The explanation of almost all the ornaments and colours of birds and insects as having been produced by the perceptions and choice of the females has, I believe, staggered many evolutionists, but has been provisionally accepted because it was the only theory that even attempted to explain the facts. It may perhaps be a relief to some of them, as it has been to myself, to find that the phenomena can be shown to depend on the general laws of development, and on the action of "natural selection," which theory will, I venture to think, be relieved from an abnormal excrescence, and gain additional vitality by the adoption of my view of the subject.

Although we have arrived at the conclusion that tropical light and heat can in no sense be considered the cause of colour, there remains to be explained the undoubted fact that all the more intense and gorgeous tints are manifested by the animal life of the tropics, while in some groups, such as butterflies and birds, there is a marked preponderance of highlycoloured species. This is probably due to a variety of causes, some of which we can indicate, while others remain to be discovered. The luxuriant vegetation of the tropics throughout the entire year, affords so much concealment, that colour may there be safely developed to a much greater extent than in climates where the trees are bare in winter, during which season the struggle for existence is

most severe, and even the slightest disadvantage may prove fatal. Equally important, probably, has been the permanence of favourable conditions in the tropics, allowing certain groups to continue dominant for long periods, and thus to carry out in one unbroken line whatever developments of plumage or colour may once have acquired an ascendency. Changes of climatal conditions, and pre-eminently the glacial epoch, probably led to the extinction of a host of highly-developed and finely-coloured insects and birds in temperate zones, just as we know that it led to the extinction of the larger and more powerful mammalia which formerly characterised the temperate zone in both hemispheres. This view is supported by the fact, that it is amongst those groups only which are now exclusively tropical, that all the more extraordinary developments of ornament and colour are found. The local causes of colour will also have acted best in regions where the climatal conditions remained constant, and where migration was unnecessary; while whatever direct effect may be produced by light or heat, will neces sarily have acted more powerfully within the tropics. And lastly, all these causes have been in action over an actually greater area in tropical than in temperate zones, while estimated potentially, in proportion to its life-sustaining power, the lands which enjoy a practically tropical climate (extending as they do considerably beyond the geographical tropics), are very much larger than the temperate regions of the earth. Combining the effects of all these various causes we are quite able to understand the superiority of the tropical parts of the globe, not only in the abundance and variety of their forms of life, but also as regards the ornamental appendages and vivid coloration which these forms present.

A. R. WALLACE.

IN 1841-3 Mrs. Austin was in Germany, and met most of the celebrated men and women of that epoch. Some of the stories jotted down by her during prolonged residence in Dresden and Berlin seem too good to be lost, while others show considerable insight into German life. The brothers Grimm appear to have been the most sympathetic people she met in Berlin About Jacob Grimm she writes thus:

"His exterior is striking and engaging. He has the shyness and simplicity of a German man of letters, but without any of the awkward, uncouth air which is too common among them. His is a noble, refined head, full of intelligence, thought, and benevolence, and his whole exterior is full of grandeur-at the same time perfectly simple. Wilhelm is also a fine-looking man, younger, fatter, and more highly-coloured; less imposing, less refined, but with a charming air of goodnature, bonhomie and sense. His wife is also very pleasing. I met him one night at tea, and we began talking of fairy tales; I said, 'Your children appear to me the happiest in the world; they live in the midst of Mährchen (fairy tales).' 'Ah,' said he, 'I must tell you about that. When we were at Göttingen somebody spoke to my little son about his father's Mährchen. He came running to me and said with an offended air, "Vater, man sagt du hast die Mährchen geschrieben-nicht wahr, du hast nicht solches Dummezeug gemacht?" ('Father, people say that you have written the fairy tales-surely you never invented such rubbish?') He thought it below my dignity,' said Grimm. Somehow the child had never

seen

or attended to the fact of his father's authorship."

Another story of Grimm's :"When I was a young man I was walking one day and saw an officer in the oldfashioned uniform. It was under the old

Elector. The officers still wore pigtails, cocked hats set over one eye, high neckcloths, and coats buttoned back. As he was walking stiffly along, a groom came by riding a horse which he appeared to be breaking in. 'What mare is that you are riding?' called out the major with an authoritative, disdainful air. She belongs to Prince George,' answered the groom. 'Ah-h!' said the major, raising his hand reverentially to his hat with a military salute, and bowing low to the mare. I told this story," continued Grimm, "to Prince B. thinking to make him laugh. But he looked grave, and said, with quite a tragic tone of voice, 'Ah, that feeling is no longer to be found!'"

"Jacob Grimm told me a Volksmährchen too :

"St. Anselm was grown old and infirm, and lay on the ground among thorns and thistles. Der liebe Gott said to him, "You are very badly lodged there; why don't you build yourself a house?" "Before I take the trouble," said Anselm, "I should like to know how long I have to live." "About thirty years," said der liebe Gott. "Oh, for so short a time," replied he, "it's not worth while," and turned himself round among the thistles.'

"Bettina von Arnim called, and we had a tête-à-tête of two hours. Her conversation is that of a clever woman, with some originality, great conceit, and vast unconscious ignorance. Her sentiments have a bold and noble character. We talked about crime, punishment, prisons, education, law of divorce, &c., &c. Gleams of truth and sense, clouds of nonsense-all tumbled out with equally undoubting confidence. Occasional great fidelity of expression. Talking of the so-called happiness and security of security of ordinary marriages in Germany, she said, Qu'est que cela me fait ? Est-ce que je me soucie de

6

ces nids qu'on arrange pour propager?' I laughed out; one must admit that the expression is most happy. She talked of the ministers with great contempt, and said, 'There is not a man in Germany; have you seen one for whom you could feel any enthusiasm ? They are all like frogs in a big pond ;well, well, let them splash their best. What have we to do with their croaking' Some things she said about the folly of attacking full-grown, habitual vice, by legislation, prison discipline, &c., were very true, and showed a great capacity for just thought. But what did she mean, or what did Schleiermacher mean, for she quoted him, by saying, 'la péché est une grâce de Dieu?' These are things people say to make one stare. Among other divorce cases we talked of was the following ::-Herr S-, a distinguished man, between fifty and sixty, with grown-up children and a wife who for five-and-twenty years had stood by his side a true and faithful partner through good and evil fortune-especially a great deal of the latter. A certain Madame A

a

woman about thirty, bien conservée, rather pretty, and extremely coquettish, made it her business to please Mr. S- and succeeded so well that he soon announced to his wife his desire to be divorced from her, and to marry Madame A- who on her side was to divorce her husband. Poor Madame S- could hardly believe her senses. She was almost stupefied. She expostulated, resisted, pleaded their childmarriageable daughters-all in vain. Mr. S- Isaid he could not be happy without Madame A. In short, as may be imagined, he wore out his wife's resistance, and the blameless, repudiated, and heart-broken wife took her children and retired into Old Prussia. Madame A- then became Madame SBut the most curious thing was that the ci-devant husband remained on terms of the greatest intimacy, and became the tame cat of the house. When Mr. S- went a journey his wife accompanied him a certain way, and Mr. A

went with

them to escort her back, as a matter of

course.

"At a ball given at C- Mr. and Madame S- were invited. He came alone, and apologised to the lady of the house about his wife's absence. She hoped Madame S- was not ill. 'Oh no; but Mr. A- has just arrived, and you understand she could not leave him alone the first evening.'

"My maid Nannie told me a curious illustration of the position of servants here. The maid belonging to the master of the house, has, it seems, a practice of running out, and being gone for hours without leave. On Sunday last she had leave; Monday, ditto; Tuesday, ditto; and was out the whole of those evenings. Wednesday she took leave, and did not return till after ten. Her mistress asked her where she had been; she refused to answer, on which her mistress pressed her. 'Well,' she said, ‘if I won't tell you, you can't hang me for it.' With which answer the lady went away content. Another day the master, who is lame, came down into the kitchen and said, 'I have left my spectacles; I wish you would run up for them.' 'Oh,' said she, 'I am washing dishes.' The droll thing is that they say they are only too glad to have this steady and obliging person, because she is honest a thing almost unknown here.

If

"A great many ladies in Berlin have evenings on which they receiveespecially the ministers' wives - not their friends, but all the world. you don't go for two or three weeks, they tell you of it- the number of omissions is chalked up against you. Nor, except in two or three of the more exotic, can you look in for half-an-hour and come away. People ask you why you go, and where you are going to. In many houses you are expected to take leave. Then you have the satisfaction of being told where you were last night, and what you said; who sat next you, and especially that you did not admire Berlin, or something in it. Of course you deny, equivocate, palliate, lie. If you have the