ORNITHOLOGY. 



629 



or inlayed by lateral lobes. Their plumage is close, often 

 glossy, and imbued with an oily fluid, which repels the 

 ' water ; and their skin is moreover covered with a dense 

 layer of down, which prevents the rapid escape of the heat 

 generated in their bodies. They are the only birds whose 

 neck exceeds their legs in length, the reason of which ar- 

 rangement is, that while swimming on the surface of the 

 water they have often to search for their food at some depth. 

 Their sternum is elongated so as to cover the greater part 

 of the viscera, and has only a lateral notch, or oval fora- 

 men, so that a large surface is afforded for the insertion of 

 the pectoral muscles. Their oesophagus is always wide, 

 their gizzard generally muscular, and their intestine fur- 

 nished with two rather long caeca. Their windpipe varies 

 in form, but the inferior larynx is simple, although in one 

 family it has a curious bony and cartilaginous dilatation. 

 This order has been divided into four families : 



1. The Brachypterce, or short-winged sea-birds, having 

 the wings very short, and the feet placed so far behind 

 that they are obliged to assume a nearly erect posture when 

 on shore. 



2. The Longipennm, or long-winged sea birds, having 

 the wings extremely long, the hind toe free or wanting, 

 and the bill horny. 



3. The Totipalmm, of which the hind toe is connected 

 with the rest by a common web, the wings long, and the 

 bill horny. 



4. The Lamellirostres, whose bill, which is thick and co- 

 vered with a soft skin, has the edges furnished with trans- 

 verse horny plates or teeth. 1 



FAMILY I BRACHYPTERjE, OR DIVERS. 



The organization of these birds renders them more aqua- 

 tic than those of any other family. Many of them reside 

 almost entirely on the waters, fly little, and walk with diffi- 

 culty, their feet being placed very far behind. Their wings 

 are generally extremely short, and their flight, although 

 sometimes rapid, is neither undulated nor buoyant. In 

 some species they are reduced to mere organs of natation, 

 the quills not being developed. All the species are furnished 

 with a dense and short plumage, swim and dive with re- 

 markable agility, and pursue their prey under the surface, 

 employing their wings as well as their feet to aid their 

 progress. They are generally distributed, migrate exten- 

 sively, and breed in society, often on rocky islands or abrupt 

 cliffs. This family may be divided into three tribes. 



1st. The divers, — Colymbida, are characterized by their 

 straight, compressed, pointed, smooth bill, linear and lateral 

 nostrils, narrow wings, and short tail. In some the feet 

 are lobed, in others webbed. 



The grebes, genus Podiceps (Plate CCCCI. fig. 1), re- 

 semble the coots in the form of their feet, their anterior 

 toes, instead of being connected by webs, being merely 

 dilated by means of lateral lobes. Their body is generally 

 short and depressed ; their neck long and slender ; their 

 bill straight, compressed, tapering, and pointed ; their nos- 

 trils linear and pervious. The legs (tibiae) are entirely 

 concealed in the abdomen ; the tarsi are extremely com- 

 pressed ; and the claw of the middle toe is flattened and 

 dilated. The plumage is remarkably soft, silky, and often, 

 especially on the lower part, has a shining gloss. Their 

 wings are very narrow, and their tail is generally reduced 

 to a slight tuft of scarcely distinguishable feathers. These 

 birds when on shore are obliged to stand in a nearly erect 

 posture ; but although they walk with difficulty, their flight 



is rapid, and their motions on the water extremely quick. 

 They dive and pursue their way under water with extreme 

 agility, and when apprehensive of danger generally disap- 

 pear under the surface, instead of flying off. Their food 

 consists of small fishes, crustacea, mollusca, and insects, 

 as well as seeds of aquatic plants ; and they nestle in marshy 

 places, laying several eggs, generally of a white colour. 

 Their plumage varies so much, according to age and sex, 

 that the species have been erroneously multiplied by au- 

 thors. Four species inhabit Europe, of which two may be 

 particularly mentioned. 



The great crested grebe, Podiceps cristatus, is of the size 

 of a mallard, blackish brown on the upper parts, with a 

 white band on the wing, and of a silvery white beneath. 

 The adults have a double black crest, and a large reddish 

 ruff or tippet margined with black, on the upper part of the 

 neck. This species inhabits the northern part of both con- 

 tinents, where it breeds, and whence it migrates southward 

 on the approach of winter. The nest is made of rushes 

 and flags, or other aquatic herbage ; and the eggs, three 

 or four in number, are of a greenish white. Several au- 

 thors allege that the female sometimes succours her young, 

 when fatigued or in danger, by carrying them on her back 

 or beneath her wings. From their surprising agility in 

 diving they are not inappropriately named water-witches 

 and dippers in America. The skins are dressed and made 

 into muffs and tippets. 



The little grebe, or dobchick, Podiceps minor, is the 

 smallest of the species, not exceeding ten inches in length. 

 It is not uncommon in most parts of Europe, as well as in 

 the north of Asia, and the country around Hudson's Bay. 

 In large rivers and lakes individuals are said to be some- 

 times devoured by pike and other fishes. In the adult the 

 upper parts are deep black, the lower silvery gray, the 

 throat black, and the neck ferruginous. 



The finfoots, Podoa, Illig., have the feet lobed like the 

 coots and grebes ; but their tail is more developed, and 

 their claws more pointed. (Plate CCCCI. fig. 2.) To this 

 genus have been referred the African finfoot, P. Senegalen- 

 sis, and the Surinam species, P. Surinamensis, which latter, 

 however, is by some considered as belonging to Anhinga. 

 The divers properly so called, genus Colymbus, greatly 

 resemble the grebes in form, but differ from them in hav- 

 ing the toes regularly webbed, and the tail moderately de- 

 veloped. Their body is elongated, and somewhat depressed ; 

 their neck long, their head small, oblong, and compressed ; 

 their bill rather long, straight, and tapering to a point ; 

 their plumage short and close ; their wings of moderate 

 length, but very narrow. These birds are peculiarly aqua- 

 tic, and while in search of food remain often longer sub- 

 merged than on the surface, to which they seem occasion- 

 ally to come merely for the purpose of respiring. They 

 feed on fishes of various kinds, but generally of small size, 

 as well as on crustacea. Like the grebes, they dive when 

 alarmed, and are not easily raised from the water, although 

 their flight, which is direct, is very rapid. On land they 

 stand erect, and walk with difficulty. They are generally 

 solitary, breed on the margins of lakes in the arctic re- 

 gions, and lay two or three very elongated, dark-coloured, 

 and spotted eggs. Their flesh is dark-coloured and unsa- 

 voury. Of this genus the more remarkable species are the 

 following. 



The great northern diver, Colymbus glacialis, is about 

 two feet and three quarters long, with the upper parts 

 black, spotted with white ; the head and neck glossy black, 

 with green reflections, the lower parts white ; the tail has 

 twenty feathers. This species is generally distributed in 



Palmi- 

 pedes. 



1 For some interesting general observations on certain genera of this order, the reader may consult " Remarks on the Pelagic Birds, 

 and on certain other Palmipedes, considered especially as regards their habits and their geographical distribution in the Oceans of the 

 Globe," published in Freycinet's Voyage autour du Monde, — Partie Zoologique, par MM. Quoy and Gaimard. 



