BI 



those species are arrived at which can neither ily nor 

 walk. The show of resemblance ma}' be said to run 

 to a termination in this group ; for, as the last ones 

 can only swim and dive, and there are no other 

 birds which can do either in greater perfection, there 

 is no point of general character upon which any 

 others can be connected with them. The popular 

 name is also not quite precise, because, though they 

 are probably the only birds which drive through the 

 water, they are not the only divers. 



The second group, LONOIPEXXES (long-winged 

 birds), agree well with the name in that part of their 

 organisation to which it applies They are the birds 

 which career over the surface of the ocean, and make 

 the shores lively with the motion of their wings, and 

 clamorous with the sound of their voices. Their food 

 and their manner of obtaining it differ so much, how- 

 ever, that they do not admit of any general description. 



The third group, TOTIJ'AI.XJUI:, or birds with the 

 feet " entirely webbed ;" that is, having the hind toe 

 considerably produced and included in the membra- 

 nous web, as well as the other three toes. These birds 

 are much longer winged than those of the preced- 

 ing group, and they are good swimmers, and some 

 of them at least can dive ; but the peculiar structure of 

 their feet, and the use which they make of these in 

 walking up to the surface of the water after they have 

 plunged into it from a considerable height, render 

 them very distinct from the other sea birds. 



The fourth and last group into which Cuvier 

 arranges these birds, LAMELLIRQSTEES, or flat-billed 

 birds, comprehending due! swans, and al- 



lied genera. There are considerable differences of 

 haunt and habit among them ; but still they are dis- 

 tinct, and well-marked as a group. But it is doubtful 

 whether they should occupy the place which Cuvier 

 assigns them, as they more resemble the divers in 

 all their general characters than they do the birds 

 of the two intermediate groups. 



Such is a short outline of the systematic arrange- 

 ment of birds, as proposed by the most scientific 

 general systematist of modern times. Many parts of 

 it are imperfect, and some arc obviously faulty ; but the 

 imperfections are much more easily felt than amended, 

 and the faults much more easily seen than corrected. 

 These imperfections and faults are also of the less im- 

 portance, inasmuch as it is in the individual genera, 

 or, at all events, in groups much smaller than most of 

 those which have been mentioned, that the real his- 

 tory of birds must be studied. We shall now, in 

 three successive sections, shortly examine and com- 

 pare the bills, the feet, and the wings of birds, as the 

 foundations of their leading characters. 



V. CoMt'AKA rivi: TOKMS OF THE BILLS OF BIRDS. 

 The armature of the jaws of birds, which answers the 

 same purpose in their economy which the lips and 

 teeth do in that of mammalia, always consists of two 

 mandibles, one placed over the other, and opening 

 and shutting chiefly by the motion of the lower one. 

 This organ is sometimes called a bill, and sometimes 

 a /.>("/, but the distinction of these names is not very 

 clear. Bill is, however, the more general of the two, 

 in the usage ; for all beaks may be called bills, but 

 all bills cannot be called beaks. According to the 

 popular understanding, which, rather than any etymo- 

 logical definition, is the rule in popular language, the 

 mandibles of a bird, in order to entitle them to the 

 name " beak," require the three attributes of firmness 

 of texture, power, which requires considerable depth 



NAT. HIST. VOL. I. 



RD. 41? 



and breadth in proportion to the length, and curva- 

 ture downwards, with pointedness at the tip of the 

 upper mandible, and projection of it over the under 

 one ; but the precise degree in which these are 

 required, as well as their relative proportions to each 

 other, is indeterminate. Those to which the term 

 beak is more generally applied are the mandibles of 

 birds of prey, and those of the parrot tribe, and some 

 other vegetable or omnivorous feeders which use this 

 organ in breaking hard substances, or in assisting in 

 the operation of climbing. 



All beaks, whether used for one purpose or for 

 another, have a considerable resemblance to each 

 other, not only in the shape but in the mode of using. 

 They are always cutting or bruising instruments, the 

 effect of which is produced by pressing the one 

 against the other, and not by striking with the point 

 or darting, as is the mode of action in many bills. 

 The form of the tomia or cutting edges, are therefore 

 the leading distinctions of different beaks, and the 

 indexes to the different characters of the owners in 

 so far as these depend upon those instruments ; 

 though there are also some corresponding differences 

 in the shape and strength. In the tomia of beaks 

 there is a slight resemblance to the teeth of animals, 

 as indicating the nature of their food. Those which 

 are carnivorous have the tomia irregular in their 

 outlines, approaching in form to something like a 

 tooth ; and those which are more exclusively vege- 

 table feeders, have the lines of the tomia le*s broken, 

 and the acting surfaces adapted simply for breaking 

 or bruising rather than for tearing asunder. Some of 

 the latter are, however, more strongly formed than 

 any of the former ; because the shells of some fruits 

 upon which certain species at times feed, require 

 more force to break them, than is required to tear 

 the average consistency of the flesh of animals, even 

 in the most recent state. But the bills of the most 

 vegetable feeders have little or no lateral motion by 

 which they can prepare the food for the stomach by 

 grinding ; and that appears to be the chief reason 

 why birds of this description always have muscular 

 gizzards, strong in proportion as their food is more 

 difficult of division. 



These characters of the tnmia belong to bills as 

 well as to beaks, though bills have in many instances 

 additional characters, such as being serrated, some- 

 times with little teeth reflected backwards along the 

 whole line of their margins, and at other times with 

 small transverse channels, or furrows, along a certain 

 breadth at the margin. The first of these descrip- 

 tions belongs principally to birds which dart upon 

 fishes, or other slippery prey ; and the latter to those 

 which dabble in the sludge, and, as it were, sift the 

 water and mud from their food by means of the 

 channels. The former are generally hard in their 

 consistency, so that they may penetrate and retain 

 their hold like barbs ; the latter are more frequently 

 soft and flexible, and there is reason to believe that 

 they are endowed with sensation, by means of which 

 they can distinguish the food from other substances, 

 and thus retain the one and reject the other. 



Bills are, however, of so many forms, and so dil- 

 ferent in the texture of their substance, that no general 

 definition can be made descriptive of them. If om- 

 nivorous, they are generally stout, sharp at the tip, 

 and with ridges on the culrnen, or centre of the upper 

 mandible, and also often at the tomia of both; and 

 these ridges, which render the bill much stronger 

 L L 



