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trogons, and pittas; but as there are were exclusively tropical, and that, perhaps an equal number of groups where a genus has a wide range, there which are wholly dull-coloured, while is little difference in coloration beothers contain dull and bright-coloured tween the species of cold and warm species in nearly equal proportions, the countries. Thus the European Vanesevidence is by no means strong that sides, including the beautiful" peatropical light or heat has anything cock," "Camberwell beauty," and "red to do with the matter. But there are admiral," butterflies, are quite up to also groups in which the cold and the average of tropical beauty in the temperate zones produce finer-coloured

same group, and the remark will equally species than the tropics. Thus the apply to the little blues" and arctic ducks and divers are handsomer “ coppers ;” while the alpine “apollo" than those of the tropical zone, while butterflies have a delicate beauty that the King-duck of temperate America can hardly be surpassed. In other inand the Mandarin-duck of N. China sects, which are less directly dependent are the most beautifully coloured of on climate and vegetation, we find the whole family. In the pheasant even greater anomalies. In the imfamily we have the gorgeous gold and mense family of the Carabidæ or silver pheasants in N. China and Mon- predaceous ground-beetles, the northgolia ; and the superb Impeyan phea- ern forms fully equal, if they do not sant in the temperate N. W. Himalayas, surpass, all that the tropics can proas against the peacocks and fire-backed duce. Everywhere, too, in hot coun: pheasants of tropical Asia. Then we tries, there are thousands of obscure have the curious fact that most of the species of insects which, if they were bright-coloured birds of the tropics are all collected, would not improbably denizens of the forests, where they are bring down the average of colour to shaded from the direct light of the much about the same level as that of sun, and that they abound near the temperate zones. equator where cloudy skies are very But it is when we come to the vege prevalent; while, on the other hand, table world that the greatest misconplaces where light and heat are at a ception on this subject prevails. In maximum have often dull-coloured abundance and variety of floral colour birds. Such are the Sahara and other the tropics are almost universally bedeserts where almost all the living lieved to be pre-eminent, not only abthings are sand-coloured ; but the most solutely, but relatively to the whole curious case is that of the Galapagos mass of vegetation and the total numislands, situated under the equator, ber of species. Twelve years of obser and not far from South America where vation among the vegetation of the the most gorgeous colours abound, eastern and western tropics has, howbut which are yet characterised by ever, convinced me that this notion is prevailing dull and sombre tints in entirely erroneous, and that, in proporbirds, insects, and flowers, so that tion to the whole number of species of they reminded Mr. Darwin of the plants, those having gaily-coloured cold and barren plains of Patagonia. flowers are actually more abundant in Insects are wonderfully brilliant in the temperate zones than between the tropical countries generally, and any tropics. This will be found to be not one looking over collection of so extravagant an assertion as it may South American or Malayan butterflies at first appear, if we consider how would scout the idea of their being no many of the choicest adornments of more gaily-coloured than the average our greenhouses and flower-shows are of European species, and in this they really temperate as opposed to tropical would be undoubtedly right. But on

plants. The masses of colour produced examination we should find that all by our Rhododendrons, Azaleas, and the more brilliantly-coloured groups Camellias, our Pelargoniums, Calceo

larias, and Cinerarias,-all strictly plants, and a great number of pecutemperate plants - can certainly not liar natural orders. be surpassed, if they can be equalled, Direct observation in tropicalforests, by any productions of the tropics. But plains, and mountains, fully supports we may go further, and say that the this view. Occasionally we are startled hardy plants of our cold temperate by some gorgeous mass of colour, but zone equal, if they do not surpass, the as a rule we gaze upon an endless exproductions of the tropics.

Let us

panse of green foliage, only here and only remember such gorgeous tribes of there enlivened by not very conflowers as the Roses, Peonies, Holly. spicuous flowers. Even the orchids, hocks, and Antirrhinums, the La- whose gorgeous blossoms adorn our burnum, Wistaria, and Lilac; the stoves, form no exception to this rule. Lilies, Irises, and Tulips, the Hya. It is only in favoured spots that we cinths, Anemones, Gentians, and find them in abundance; the species Poppies, and even our humble Gorse, with small and inconspicuous flowers Broom, and Heather; and we may greatly preponderate ; and the flowerdefy any tropical country to produce ing season of each kind being of short masses of floral colour in greater abun- duration, they rarely produce any dance and variety. It may be true that marked effect of colour amid the vast individual tropical shrubs and flowers masses of foliage which surround do surpass everything in the rest of

them. An experienced collector in the world, but that is to be expected, the Eastern tropics once told me, that because the tropical zone comprises a although a single mountain in Java much greater land-area than the two had produced three hundred species of temperate zones, while, owing to its Orchideæ, only about 2 per cent. of the more favourable climate, it produces a whole were sufficiently ornamental or still larger proportion of species of showy to be worth sending home as a

commercial speculation. The alpine 1 It may be objected that most of the plants named are choice cultivated varieties, far sur

meadows and rock-slopes, the open passing in colour the original stock, while the plains of the Cape of Good Hope or tropical plants are mostly unvaried wild species.

of Australia, and the flower-prairies But this does not really much affect the ques. tion at issue. For our florists' gorgeous varie

of North America, offer an amount ties have all been produced under the influence and variety of floral colour which can of our cloudy skies, and with even a still certainly not be surpassed, even if it further deficiency of light, owing to the neces- can be equalled, between the tropics. sity of protecting them under glass from our sudden changes of temperature ; so that they

It appears, therefore, that we may are themselves an additional proof that tropi

dismiss the theory that the developcal light and heat are not needed for the pro- ment of colour in nature is directly duction of intense and varied colour. Another

dependent on, and in any way proporimportant consideration is, that these cultivated varieties in many cases displace a

tioned to the amount of solar heat and number of wild species which are hardly, if light, as entirely unsupported by facts. at all, cultivated. Thus there are scores of Strange to say, however, there are some species of wild hollyhocks varying in colour rare and little-known phenomena, which almost as much as the cultivated varieties, and the same may be said of the pentstemons,

prove that, in exceptional cases, light rhododendrons, and many other flowers; and

does directly affect the colours of if these were all brought together in well- natural objects, and it will be as well grown specimens, they would produce a grand to consider these before passing on to effect. But it is far easier, and more profit

other matters. abl for our nurserymen to grow varieties of one or two species, which all require a very similar culture, rather than fifty distinct A few years ago Mr. T. W. Wood species, most of which would require special called attention to the curious changes treatment; the result being that the varied beauty of the temperate flora is even now

in the colour of the chrysalis of the hardly known, except to botanists and to a few

small cabbage butterfly (Pontia rapæ) amateurs,

when the caterpillars were confined

and

trogons, and pittas; but as there are were exclusively tropical, and that, perhaps an equal number of groups where a genus has a wide range, there which are wholly dull-coloured, while is little difference in coloration beothers contain dull and bright-coloured tween the species of cold and warm species in nearly equal proportions, the countries. Thus the European Vanesevidence is by no means strong that sides, including the beautiful “ peatropical light or heat has anything cock," "Camberwell beauty," and "red to do with the matter. But there are admiral.” butterflies, are quite up to also groups in which the cold and the average of tropical beauty in the temperate zones produce finer-coloured

same group, and the remark will equally species than the tropics. Thus the apply to the little

“ blues" arctic ducks and divers are handsomer coppers ;” while the alpine “apollo.” than those of the tropical zone, while butterflies have a delicate beauty that the King-duck of temperate America can hardly be surpassed. In other inand the Mandarin-duck of N. China sects, which are less directly dependent are the most beautifully coloured of on climate and vegetation, we find the whole family. In the pheasant even greater anomalies. In the imfamily we have the gorgeous gold and mense family of the Carabidæ or silver pheasants in N. China and Mon- predaceous ground-beetles, the northgolia ; and the superb Impeyan phea- ern forms fully equal, if they do not sant in the temperate N. W. Himalayas, surpass, all that the tropics can proas against the peacocks and fire-backed duce. Everywhere, too, in hot counpheasants of tropical Asia. Then we tries, there are thousands of obscure have the curious fact that most of the species of insects which, if they were bright-coloured birds of the tropics are all collected, would not improbably denizens of the forests, where they are bring down the average of colour to shaded from the direct light of the much about the same level as that of sun, and that they abound near the temperate zones. equator where cloudy skies are very But it is when we come to the vegeprevalent; while, on the other hand, table world that the greatest misconplaces where light and heat are at a ception on this subject prevails. In maximum have often dull-coloured abundance and variety of floral colour birds. Such are the Sahara and other the tropics are almost universally be deserts where almost all the living lieved to be pre-eminent, not only abthings are sand-coloured ; but the most solutely, but relatively to the whole curious case is that of the Galapagos mass of vegetation and the total numislands, situated under the equator, ber of species. Twelve years of obserand not far from South America where vation among the vegetation of the the most gorgeous colours abound, eastern and western tropics has, howbut which are yet characterised by ever, convinced me that this notion is prevailing dull and sombre tints in entirely erroneous, and that, in proporbirds, insects, and flowers, so that tion to the whole number of species of they reminded Mr. Darwin of the plants, those having gaily-coloured cold and barren plains of Patagonia. Howers are actually more abundant in Insects are wonderfully brilliant in the temperate zones than between the tropical countries generally, and any tropics. This will be found to be not one looking over

collection of so extravagant an assertion as it may South American or Malayan butterflies at first appear, if we consider how would scout the idea of their being no many of the choicest adornments of more gaily-coloured than the average our greenhouses and flower-shows are of European species, and in this they really temperate as opposed to tropical would be undoubtedly right. But on

plants. The masses of colour produced examination we should find that all by our Rhododendrons, Azaleas, and the more brilliantly-coloured groups Camellias, our Pelargoniums, Calceo

a

masses

larias, and Cinerarias,-all strictly plants, and a great number of pecutemperate plants --can certainly not liar natural orders. be surpassed, if they can be equalled, Direct observation in tropicalforests, by any productions of the tropics. But plains, and mountains, fully supports we may go further, and say that the this view. Occasionally we are startled hardy plants of our cold temperate by some gorgeous mass of colour, but zone equal, if they do not surpass, the as a rule we gaze upon an endless exproductions of the tropics.

Let us

panse of green foliage, only here and only remember such gorgeous tribes of there enlivened by not very conflowers as the Roses, Peonies, Holly- spicuous flowers. Even the orchids, hocks, and Antirrhinums, the La- whose

gorgeous

blossoms adorn our burnum, Wistaria, and Lilac; the stoves, form no exception to this rule. Lilies, Irises, and Tulips, the Hya. It is only in favoured spots that we cinths, Anemones, Gentians, and find them in abundance; the species Poppies, and even our humble Gorse, with small and inconspicuous flowers Broom, and Heather; and we may greatly preponderate ; and the flowerdefy any tropical country to produce ing season of each kind being of short masses of floral colour in greater abun- duration, they rarely produce any dance and variety. It may be true that

marked effect of colour amid the vast individual tropical shrubs and flowers

of foliage which surround do surpass everything in the rest of them. An experienced collector in the world, but that is to be expected, the Eastern tropics once told me, that because the tropical zone comprises a although a single mountain in Java much greater land-area than the two had produced three hundred species of temperate zones, while, owing to its Orchideæ, only about 2 per cent. of the more favourable climate, it produces a whole were sufficiently ornamental or still larger proportion of species of showy to be worth sending home as a

commercial speculation. The alpine 1 It may be objected that most of the plants named are choice cultivated varieties, far sur

meadows and rock-slopes, the open passing in colour the original stock, while the plains of the Cape of Good Hope or tropical plants are mostly unvaried wild species.

of Australia, and the flower-prairies But this does not really much affect the question at issue. For our florists' gorgeous varie

of North America, offer an amount ties have all been produced under the influence and variety of floral colour which can of our cloudy skies, and with even a still certainly not be surpassed, even if it further deficiency of light, owing to the neces- can be equalled, between the tropics. sity of protecting them under glass from our sudden changes of temperature ; so that they

It appears, therefore, that we may are themselves an additional proof that tropi.

dismiss the theory that the developcal light and heat are not needed for the pro- ment of colour in nature is directly daction of intense and varied colour. Another dependent on, and in any way proporimportant consideration is, that these culti

tioned to the amount of solar heat and vated varieties in many cases displace a number of wild species which are hardly, if light, as entirely unsupported by facts. at all, cultivated. Thus there are scores of Strange to say, however, there are some species of wild hollyhocks varying in colour rare and little-known phenomena, which almost as much as the cultivated varieties, and the same may be said of the pentstemons,

prove that, in exceptional cases, light rhododendrons, and many other flowers ; and

does directly affect the colours of if these were all brought together in well- natural objects, and it will be as well grown specimens, they would produce a grand to consider these before passing on to effect. But it is far easier, and more profit

other matters. able, for our nurserymen to grow varieties of one or two species, which all require a very similar culture, rather than fifty distinct A few years ago Mr. T. W. Wood species, most of which would require special called attention to the curious changes treatment; the result being that the varied

in the colour of the chrysalis of the beauty of the temperate flora is even now hardly known, except to botanists and to a few

small cabbage butterfly (Pontia rapa) amateurs.

when the caterpillars were confined

on

in boxes lined with different tints. These remarkable changes would Thus in black boxes they were very perhaps not have been credited, had dark, in white boxes nearly white; it not been for the previous obserand he further showed that similar vations of Mr. Wood; but the two changes occurred in a state of nature, support each other, and oblige us to chrysalises fixed against a white- accept them as actual phenomena. It washed wall being nearly white, is a kind of natural photography, the against a red brick wall reddish, particular coloured rays to which the against a pitched paling nearly black. fresh pupa is exposed in its soft, semiIt has also been observed that the transparent condition, effecting such a cocoon of the emperor moth is either chemical change in the organic juices white or brown, according to the as to produce the same tint in the surrounding colours. But the most hardened skin. It is interesting, howextraordinary example of this kind of ever, to note that the range of colour change is that furnished by the chry

that can

be acquired seems to be salis of an African butterfly (Papilio limited to those of natural objects to Nireus), observed at the Cape by Mrs. which the pupa is likely to be attached; Barber, and described (with a coloured for when Mrs. Barber surrounded one plate) in the Transactions of the Ento. of the caterpillars with a piece of mological Society, 1874, p. 519. The scarlet cloth no change of colour at caterpillar feeds on the orange tree, all was produced, the pupa being of the and also a forest tree (Vepris usual green tint, but the small red lanceolata) which has a lighter green spots with which it is marked were leaf, and its colour corresponds with brighter than usual. that of the leaves it feeds upon, being In these caterpillars and pupa, as of a darker green when it feeds on the well as in the great majority of cases o ange. The chrysalis is usually found in which a change of colour occurs in suspended among the leafy twigs of animals, the action is quite involuntary; its food-plant, or of some neighbouring but among some of the higher animals tree; but it is probably often at- the colour of the integument can be tached to larger branches, and Mrs. modified at the will of the animal, or Barber has discovered that it has the at all events by a reflex action dependproperty of acquiring the colour, more ent on sensation. The most remarkor less accurately, of any natural object able case of this kind occurs with the it may be in contact with. A number Chameleon, which has the power of of the caterpillars were placed in a changing its colour from dúll white case with a glass cover, one side of the to a variety of tints. This singular case being formed by a red brick wall, power has been traced to two layers of the other sides being of yellowish wood. pigment deeply seated in the skin, They were fed on orange leaves, and from which minute tubes, or capillary a branch of the bottle-brush tree vessels, rise to the surface. The pig: (Banksia, sp.) was also placed in the ment-layers are bluish and yellowish, When fully fed, some attached and by the pressure

of suitable themselves to the orange twigs, others muscles these can be forced upwards to the bottle-brush branch ; and these either together or separately. When all changed to green pupæ ; but each no pressure is exerted the colour is corresponded exactly in tint to the dirty white, which changes to various leaves around it, the one being dark tints of bluish, green, yellow, or the other a pale faded green. Another brown, as more or less of either pigattached itself to the wood, and the ment is forced up and rendered visible. pupa became of the same yellowish The animal is excessively sluggish and colour; while one fixed itself just where defenceless, and its power of changing the wood and brick joined, and became its colour to harmonise with surroundone side red, the other side yellow ! ing objects is essential to its existence.

case.

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