410 



BIRD. 



themselves, very precise, tis Omnivora is rather too 

 general a name, and other birds are scarcely less 

 omnivorous than them, as, for instance, poultry are 

 very miscellaneons feeders. Granivora is quite as 

 vague, as pigeons, and some other birds, feed as much 

 on the seeds of vegetables as the birds of this division. 



Still, as applied to the extremes of the division, 

 these names, with some explanation, would not be 

 undescriptive. But it would not be easy to make a 

 perfect separation of the two, for their characters 

 pass so gradually into each other, that there are 

 many genera of which it would be no easy matter to 

 decide whether they are more omnivorous or more 

 granivorous , and thus their place in the one group 

 or the other would be much more a matter of fancy 

 than a matter of science. 



This blending of characters on the confines of the 

 different divisions, in what manner soever those divi- 

 sions are made, is, in addition to the confusion pro- 

 duced by the three principal means of classification, 

 one of the great difficulties in the proper arrangement 

 of birds. If the comparison may be allowed, birds 

 arc like the tints of the rainbow ; we can call these 

 red in one part, yellow in a second, green in a third, 

 and so on ; but no art can fix a line any where in 

 the bow which can so divide colour from colour, as to 

 enable one to say, " all on this side is yellow, and all 

 on the other side is red." Even the colour which we 

 can name the most readily is of no measurable breadth 

 as one uniform tint; for the moment that we, for in- 

 stance, lose the red on the one side of the yellow we 

 begin to find the green on the other ; and therefore, 

 however small a portion of the breadth we take, we 

 always find that, as compared with the whole, it dis- 

 plays rnore than one tint. 



It is very much the same with birds; and birds, 

 like rainbows, are children of the sun, more affected 

 by that luminary than any other vertebrated animals, 

 and partaking more of those radiant hues white the 

 pencil of the sun alone can limn. We never can 

 draw a definite line between order and order, or group 

 and group ; and as little can we find even a single 

 genus which has no conformation or habit in com- 

 mon with another. When we put the rest of the 

 rainbow out of consideration, we can give a name to 

 the tint of any particular part; and, in like manner, 

 when we take a single species of bird, and examine 

 it without reference to the rest of the class, we can 

 describe all its appearances and habits, so far as they 

 are known to us, in a manner perfectly satisfactory. 

 We can thus study birds, and know them, and learn 

 from them, with perfect ease and certainty ; but we 

 cannot classify them. 



The great locomotive powers of birds are among 

 the chief causes of this. What with their ordinary 

 journeys, and what with their seasonal migratory ones, 

 they are here, there, and everywhere. Sea or land, 

 mountain or plain, waste or cultivated field, we find 

 them there as inhabitants or as passengers ; and there 

 is not a spot of land or spot of water but may become 

 the inn of a wayfaring bird. Their clothing adapts 

 them well to the weather; and it is necessary that 

 they should not be very particular in their food, for 

 they are exposed to many changes of it, and must 

 frequently take what they can find without any choice. 

 It is for this reason that classifications founded on 

 the shape of the bill fail so much in other respects ; 

 and this is peculiarly the case with the dentirostres 

 and conirostres of Cuvier's order Passcrfs, whose 



bills are very differently formed in the different 

 genera. 



The Tcnuirostrcs, or slender-bills, form a much 

 more natural division, though they too vary consider- 

 ably in the different genera, both in the kind of their 

 food and in the places and manner of finding it. 

 Their bills in general accord with the name in being 

 slender ; but the smallness of their diameter is no 

 indication of weakness. On the other hand, they are 

 very firm in their texture ; and though, from their 

 form, they are riot so well adapted for breaking hard 

 substances between the mandibles as the larger 

 hard bills of the former division, they can reach their 

 food in places which are not accessible to these. 

 Many of them are bark birds, which run in all direc- 

 tions upon the boles and larger branches of trees, 

 and extract the insects or larvae which are lodged in 

 the crevices. Some of them run upon walls and 

 rocks, and catch spiders in the same manner; while 

 some again hover over the nectaries of Howers, from 

 which they extract honey or small insects. They 

 are an interesting race, from the agility of their 

 motions, often for the brilliancy of their colours, fre- 

 quently for their great power of wing as compared 

 with their size, and not unfrequently for their extreme 

 littleness. The humming-birds, which make the air 

 under the action of the equatorial sun so gay with 

 glearoy tints as if all the gems and the finest metals 

 were Hying about, belong to this division ; and some 

 of them, while to appearance not bigger than humble- 

 bees, have the sternum and all the apparatus of flight 

 nearly as well developed and as perfect as in the jer 

 falcon. 



But though this division is a very natural one, it is 

 doubtful whether the bill is the best foundation for 

 their natural distinction from other birds, as it is nei- 

 ther their most constant nor their most conspicuous 

 character. The bill is always slender at the tip, and 

 it cannot be said in any instance to be thick in pro- 

 portion to its length, but it is often a large bill for the 

 size of the bird, and it varies considerably in shape. 

 Thus in the nuthatch the bill is straight, very strong 

 for its thickness, being fortified with angular ridges 

 on the culmen and at the edges of the mandibles ; 

 and thus it is capable of digging into the bark of trees, 

 or hewing open the shells of nuts. It is partially a 

 vegetable and partially an insect feeder. The rest of 

 the family or division' have the bill of weaker struc- 

 ture, generally larger, more slender, and not so straight ; 

 and some of the humming-birds have the tip of it so 

 formed as to answer as a sucker. Thus, though the 

 bills of all may without impropriety be said to be 

 slender, yet slenderness is not a character of them, 

 neither have they any one remarkable charactei 

 which is common to the whole. 



The feet form a better, or, at all events, a more 

 constant character. These are all of the kind of 

 double climbing or perching feet, of which some ac- 

 count will be found in the article ANISOBACTYU ; 

 and the using of these as characteristic of the division, 

 rather than the mere slenderness of the bill, which, 

 as has been said, is not a very constant character, is 

 attended with some other advantages. It leads more 

 naturally not only to the folio-wing and last division of 

 this order, but to the order which Cuvier has placed 

 next in succession, and which, if we take the general 

 habits of the birds in both, has really more of what is 

 called natural affinity to this division than it has to 

 the one which Cuvier interpolates between them. 



