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THE POPULAR SCIENCE MONTHLY.— SUPPLEMENT. 



It is undoubtedly the case that there are an 

 immensely greater number of richly-colored birds 

 and insects in tropical than in temperate and 

 cold countries ; but it is by no means so certain 

 that the proportion of colored to obscure species 

 is much or any greater. Naturalists and col- 

 lectors well know that the majority of tropical 

 birds are dull-colored ; and there are whole fami- 

 lies, comprising hundreds of species, not one of 

 which exhibits a particle of bright color. Such 

 are the Timaliida3 of the Eastern and the Dendro- 

 colaptidae of the Western Hemispheres. Again, 

 many groups of birds, which are universally dis- 

 tributed, are no more adorned with color in the 

 tropical than in the temperate zone ; such are 

 thrushes, wrens, goat-suckers, hawks, grouse, 

 plovers, and snipe ; and if tropical light and heat 

 have any direct coloring effect, it is certainly 

 most extraordinary that in groups so varied in 

 form, structure, and habits, as those just men- 

 tioned, the tropical should be in no wise dis- 

 tinguished in this respect from the temperate 

 species. The brilliant tropical birds mostly be- 

 long to groups which are wholly or almost wholly 

 tropical — as the chatterers, toucans, trogons, and 

 pittas ; but as there are, perhaps, an equal num- 

 ber of groups which aro wholly dull-colored, 

 while others contain dull and bright colored spe- 

 cies in nearly equal proportions, the evidence is 

 by no means strong that tropical light or heat 

 has anything to do with the matter. But there 

 are also groups in which the cold and temperate 

 zones produce finer-colored species than the 

 tropics. Thus the arctic ducks and divers are 

 handsomer than those of the tropical zone, while 

 the king-duck of temperate America and the 

 mandarin-duck of Northern China are the most 

 beautifully colored of the whole family. In the 

 pheasant family we have the gorgeous gold and 

 silver pheasants in Northern China and Mongolia ; 

 and the superb impeyan pheasant in the temper- 

 ate Northwest Himalayas, as against the peacocks 

 and fire-backed pheasants of tropical Asia. 'Then 

 we have the curious fact that most of the bright- 

 colored birds of the tropics are denizens of the 

 forests, where they are shaded from the direct 

 light of the sun, and that they abound near the 

 equator, where cloudy skies are very prevalent ; 

 while, on the other hand, places where light and 

 heat are at a maximum have often dull- colored 

 birds. Such are the Sahara and other deserts, 

 where almost all the living things are sand- 

 colored ; but the most curious case is that of the 

 Galapagos Islands, situated under the equator, 

 and not far from South America, where the most 



gorgeous colors abound, but which are yet char- 

 acterized by prevailing dull and sombre tints in 

 birds, insects, and flowers, so that they reminded 

 Mr. Darwin of the cold and barren plains of Pata- 

 gonia. Insects are wonderfully brilliant in tropi- 

 cal countries generally, and auy one looking over 

 a collection of South American or Malayan but- 

 terflies would scout the idea of their being no 

 more gayly colored than the average of European 

 species, and in this they would be undoubtedly 

 right. But on examination we should find that 

 all the more brilliantly colored groups were ex- 

 clusively tropical, and that, where a genus has a 

 wide range, there is little difference in coloration 

 between the species of cold and warm countries. 

 Thus the European Vanessides, including the 

 beautiful " peacock," '" Camberwell beauty," and 

 " red admiral " butterflies, are quite up to the 

 average of tropical beauty in the same group, 

 and the remark will equally apply to the little 

 "blues" and "coppers;" while the Alpine 

 " apollo " butterflies have a delicate beauty that 

 can hardly be surpassed. In other insects, which 

 are less directly dependent on climate and vege- 

 tation, we find even greater anomalies. In the 

 immense family of the Carabidae or predaceous 

 ground-beetles, the northern forms fully equal, if 

 they do not surpass, all that the tropics can pro- 

 duce. Everywhere, too, in hot countries, there 

 are thousands of obscure species of insects which, 

 if they were all collected, would not improbably 

 bring down the average of color to much about 

 the same level as that of temperate zones. 



But it is when we come to the vegetable 

 world that the greatest misconception on this- 

 subject prevails. In abundance and variety of 

 floral color the tropics are almost universally be- 

 lieved to be preeminent, not only absolutely, but 

 relatively to the whole mass of vegetation and 

 the total number of species. Twelve years of 

 observation among the vegetation of the Eastern 

 and Western tropics has, however, convinced me 

 that this notion is entirely erroneous, and that, 

 in proportion to the whole number of species 

 of plants, those having gayly-colored flowers are 

 actually more abundant in the temperate zones 

 than between the tropics. This will be found to 

 be not so extravagant an assertion as it may at first 

 appear, if we consider how many of the choicest 

 adornments of our greenhouses and flower-shows 

 are really temperate as opposed to tropical plants. 

 The masses of color produced by our rhododen- 

 drons, azaleas, and camellias, our pelargoniums, 

 calceolarias, and cinerarias — all strictly temperate 

 plants — can certainly not be surpassed, if they 



