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Albatros of ed of all to have description
Albatros of many authors. Of this, though it has been so long the observed of all observers among voyagers to the Southern Ocean, no one seems to have given, from the life, its finished portrait on the wing, and hardly such a description as would enable those who have not seen it to form an idea of its look. The diagrammatic sketch by Captain (now Professor) Hutton, here introduced, is prob
Now Phan description
ALBATROS. (After Hutton. From the Philos. Mag. Aug. 1869, with the
Editor's permission.) ablya more correct representation of it than can be found in the conventional figures which abound in books. Writers who apply to its FLIGHT the epithets graceful, grand, majestic, and the like, convey thereby no definite meaning, and yet by all accounts its appearance must be extremely characteristic. The ease with which it maintains itself in the air, “sailing" for a long while without any perceptible motion of its wings, whether gliding over the billows, or boldly shooting aloft again to descend and possibly alight on the surface, has been dwelt upon often enough, as has its capacity to perform these feats equally in a seeming calm or in the face of a gale ; but more than this is wanted, and one must hope that a series of instantaneous photographs may soon be obtained which will shew the feathered aeronaut with becoming dignity. The mode in which the “sailing” of the Albatros is effected has been much discussed, but there can be little doubt that Professor Hutton is right in declaring (Ibis, 1865, p. 296) that it is only “by combining, according to the laws of mechanics,
1 The most vivid description is perhaps that of Mr. Froude (Oceana, pp. 65, 66), and, as it is cited with approval by Sir W. Buller (B. New Zeal. ed. 2, ii. p. 195), a part may here be quoted. The Albatros “wheels in circles round and round, and for ever round the ship--now far behind, now sweeping past in a long rapid curve, like a perfect skater on an untouched field of ice. There is no effort ; watch as closely as you will, you rarely or never see a stroke of the mighty pinion. The flight is generally near the water, often close to it. You lose sight of the bird as he disappears in the hollow between the waves, and catch him again as he rises over the crest ; but how he rises and whence comes the propelling force is to the eye inexplicable ; he alters merely the angle at which the wings are inclined ; usually they are parallel to the water and horizontal ; but when he turns to ascend or makes a change in his direction the wings then point at an angle, one to the sky, the other to the water.”
this pressure of the air against his wings with the force of gravity, and by using his head and tail as bow and stern rudders, that the Albatros is enabled to sail in any direction he pleases, so long as his momentum lasts." Much discrepancy, at present inexplicable, exists in the accounts given by various writers of the expanse of wing in this species. We may set aside as a gross exaggeration the assertion that examples have been obtained measuring 20 feet, but Dr. George Bennett of Sydney (Wanderings, &c., ii. p. 363) states that he has “never seen the spread of the wings greater than fourteen feet.” Recently Mr. J. F. Green (Ocean Birds, p. 5) says that, out of more than one hundred which he had caught and measured, the largest was 11 feet 4 inches from tip to tip, a statement exactly confirmed, he adds, by the forty years' experience of a ship-captain who had always made a point of measuring these birds, and had never found one over that length.
This Albatros is too well known by description in countless books, or by specimens to be seen in almost any museum, to need many words as to its chief features. In the adult the plumage of the body is white, more or less mottled above by fine wavy bars, and the quill-feathers of the wings are brownish-black. The young are suffused with slaty-brown, the tint becoming lighter as the bird grows older. It is found throughout the Southern Ocean, seldom occurring northward of lat. 30° S., and is invariably met with by ships that round the Cape of Good Hope or pass the Strait of Magellan. As a species it is said to be less numerous than most of its smaller congeners, and one cannot but fear that it will become rarer still, if not extinct, partly because of the senseless slaughter to which it is subjected by the occupants of almost every ship, but especially because of the ravages inflicted upon it at its not too many breeding-places, which are on islands mostly small and remote, where disastrous havoc can be, and continually is, wrought by a boat's crew in a few hours.
In the North-Pacific Ocean are found two other large species of Albatros, regarded for a long time by ornithologists as identical with D. exulans, but now recognized as being distinct species. They have also been confounded with one another by some authors, while the young have been described as if different from their parents, so that their nomenclature presents a tangled puzzle which it would be impossible here to unravel. Enough to say, that the one of them which is most like D. exulans, and has over and over again been so termed by authors, is the D. albatrus of Pallas, its young being the D. derogata of Swinhoe. This seems to be always
i Instances are recorded of its occurrence in Europe and North America, and no doubt examples of some species of Albatros have wandered so far from their usual range ; but whether D. exulans is one of them seems to await proof. Fossil remains of Diomedea have been found in Suffolk (Q. J. Geol. Soc. 1886, p. 367).
distinguishable by its yellow or light-coloured legs, while the other, the D. brachyura of Temminck, its young being the D, nigripes of Audubon, has those limbs dark or black. Both of them seem to occur in summer in Bering Sea, while they occasionally appear along the shores of China and California ; but nothing can yet be said as to their precise range. It remains to mention the smaller species of the genus, one of which, D. cauta, described by Gould, is not much inferior in size to the preceding, and owing to its wary disposition, indicated by the trivial name it bears, is extremely rare in collections. These are all known to seafaring men as Mollymauks—a corruption of MALLEMUCK—and chiefly frequent the Southern Ocean, as does also the Sooty Albatros, which, from its wedge-shaped tail, has been placed in a genus of its own, and passes as Phoebetria fuliginosa.
ALBINO (coll. n. albinism). A case of HETEROCHROSIS, produced by the partial or total absence of the normally-present black pigment in the feathers and other parts. In complete albinos the pupil and iris are red, owing to the blood vessels shining through these otherwise strongly pigmented parts. A lesion of the pulp of a growing feather not unfrequently prevents the deposition of pig. ment therein, but the pulp recovers' as a rule after one or more moults (see Colour).
ALECTORIDES, an Order proposed by Temminck in 1820 (Man. d'Orn. ed. 2, i. p. xcv.) to contain the genera Psophia (TRUMPETER), Dicholophus (SERIEMA), Glareola (PRATINCOLE), Palamedea, and Chauna (SCREAMER). Sundevall subsequently (K. Vet. Acad. Handlingar, 1836, p. 120) substituted Otis (BUSTARD) for Glareola, but wholly dropped the group in his Tentamen (1872-73) wherein these forms are differently disposed. The Order has, however, been admitted by several other systematists, and among them by Mr. Sclater, who, in 1880, made it include six Families (see INTRODUCTION).
ALECTOROMORPHÆ, according to Prof. Huxley's arrangement (Proc. Zool. Soc. 1867, pp. 456, 459), the fifth group of SCHIZOGNATHÆ, corresponding practically with the GALLINÆ of Linnæus; and, omitting the genera Opisthocomus (HOACTZIN) and Menura (LYRE-BIRD), with the section Gallinacei of Illiger's RASORES.
ALK, the old and apparently the more correct form of AUK.
ALLANTOIS (from állás, a sausage). A sack-like structure, which during the very early development of the embryo grows out from the posterior gut into the body cavity, and extends rapidly all round the embryo in the space enclosed by the false amnion, forming then with the latter a highly vascular inner lining of the eggshell. This bag receives urine, and takes on respiratory functions in embryonic Birds and Reptiles. Towards the end of incubation the allantois shrivels up, and is cast off with the shell ; its stalk or urachus, from the cloaca to the navel, is gradually absorbed, there being no urinary bladder in Birds (see EMBRYOLOGY).
ALP, otherwise ALPH, AWBE, or OLPH, a word of unknown origin, but of long standing (see Chaucer, Romaunt of the Rose, circa 1400), and still locally used in one or other of its forms, e.g. “BloodOlph” and “Green-Olph ” for the BULLFINCH and GREENFINCH respectively.
ALTRICES, the name given by Sundevall (K. Vet. Acad. Handl. 1836, p. 64) to his first section of the Class Aves, comprehending those which “alunt pullulos” (feed their young), founded on the scheme of Oken (Lehrb. d. Zoologie, p. 371), in opposition to PRÆCOCES, the birds which at birth are more or less able to feed themselves, but subsequently abandoned by its inventor (Tentamen, p. xx., Nicholson's transl. p. 26).
The division of the Class thus indicated has under various names been advocated by several authorities, and at first sight has a plausible appearance; but investigation shews that it cannot be adopted. Doubtless the original Birds, like Reptiles, were Præcoces, and the Altrices are of later date. The existence of the numerous intermediate forms may thus be explained; but it follows that we cannot use as absolutely valid differentiating characters such as are afforded by the open or closed eyes of the young at birth, by their being clothed in down or naked, by their remaining in the nest or not, by their way of feeding themselves or being fed. It is possible that the transition from Præcoces to Altrices has been governed by purely external circumstances, which may still be in action—such, for instance, as the nest being built high above the ground or water. There are many Altrices whose whole anatomical structure proves them to be more nearly related to certain groups of typical Præcoces than they are to other Altrices. These circumstances as fully explained (Jenaisch. Zeitschrift, 1879, p. 385, and Bronn, Thierreich, Aves. p. 701) lead to the following divisions of birds in regard to their development:1. PRÆCOCES or Nidifugæ-hatched with eyes open ; thickly clad in
down; able to run at once, or almost at once ; and having such an amount of yolk stored in the abdomen as to render them for some time more or less independent of other food :-Ratita, Crypturi, Gallina, Laridæ, Limicolæ, Pteroclidæ, Grallæ, Anseres,
Pygopodes. 2. ALTRICES or Nidicolaa. Lower Nidicolæ—some hatched with their eyes open, others
blind ; covered or not with down ; unable to leave the nest; fed by the parents ; amount of food-yolk very limited :Spheniscidæ, Steganopodes, Tubinares, Herodii, Pelargi.
b. Higher Nidicolæ-hatched in a helpless condition, blind ;
mostly naked, and for a long time nursed in the nest, the
Cypselomorphæ, Pici, Passeres.
AMAZON, a bird-fanciers' name for a certain group of PARROTS belonging chiefly to the genus Chrysotis.
AMBIENS is a muscle (so called by Sundevall, Förhandl. Skand. Naturf. 1851, pp. 259-269 : abstract in Rep. Brit. Assoc. 1855, Trans. of Sect. p. 137) which, arising from the pectineal process of the pelvis, runs along the inner surface of the thigh, passes the knee as a string-like tendon, and then forms one of the heads of the deep flexor muscle of the second and third toe. The taxonomic value of this muscle has been much over-estimated since Garrod (P. 2. S. 1874, pp. 111-123) divided the Class into HOMALOGONATÆ, birds possessing an ambiens muscle, and ANOMALOGONATÆ, or birds without such a muscle. The muscle is typically developed in Crypturi, Gallinæ, Pteroclidæ, Grallæ, Laridæ, Colymbidæ, Steganopodes, Impennes, Anseres, Accipitres, Coccyges ; it is absent in all Striges, Cypselomorpha, Halcyones, Epopes, Trogonidæ, Pici, Passeres, Herodii, Alcidæ, Podicipedidæ ; it is very variable in Ratitæ, Pelargi, Tubinares, Columbæ, Psittaci (see also MUSCULAR SYSTEM and INTRODUCTION).
AMIDAVAD, otherwise AMADAVAT, or AVADUVAT, the name given to a well-known favourite cage-bird, Estrilda amandara (see WEAVER-BIRD), being a corruption of Ahmadabad, the name of a town in Goojerat whence, more than 200 years ago, according to Fryer (New Account of East India, &c., London: 1698), examples were brought to Surat. In his peculiar style he tells us (p. 116) that “they are spotted with White and Red, no bigger than Measles, the principal Chorister beginning, the rest in Concert, Fifty in a cage, make an admirable Chorus.”
AMNION (a Greek word of doubtful derivation, used already by Aristotle). From either end of the body of the very early embryo grows out a fold which passes dorsally over the embryo, and unites above it with its fellow from the other end; between the two layers of this double fold, which is the amnion, extends the body-cavity, and receives the rapidly-growing ALLANTOIS ; the outer membrane of the allantois fuses with the outer double fold of the amnion, and forms the chorion, lining the eggshell (see EMBRYOLOGY). The amnion affords one of the principal differentiating characters in the vertebrata ; Reptiles, Birds, and Mammals are as Amniota (Hæckel, Anthropogenie, 1874) opposed to Amphibians and Fishes or Anamnia.