Popular JBtctionart? of 



43 



Aiiricula Midcc, or Midas' Ear, is a hand- 

 some shell, native of the East Indies : its 

 figure is oval or oblong ; the mouth longi- 

 tudinal, with a reflected lip. 



AUXIS. A fish belonging to the Scom- 

 ber ifhs or Mackerel family, found in the 

 Mediterranean. It is of a fine blue black 

 on the back, with oblique blackish lines, 

 and the flesh deep red. 



AVES. [BIRDS.] The name of a class of 

 vertebrated animals, characterized by ovipa- 

 rous generation, a covering of feathers, and 

 by their anterior extremities being organized 

 as wings, and mostly used for flight. There 

 are six orders, which are distinguished by 

 certain characteristics of the posterior ex- 

 tremities or feet. The FIKST order is termed 

 Raptorvs or Accipitres; they have large feet, 

 with three toes before and one behind, all 

 armed with long, strong, sharp, curved, and 

 prehensile talons ; this structure is asso- 

 ciated with a strong, curved, and sharp- 

 pointed beak ; a very muscular body ; and 

 capability of rapid and long-continued flight. 

 These are Birds of Prey ; the principal of 

 them being Vultures, Eagles, Hawks, Kites, 

 Buzzards, and Owls. The SECOXD order is 

 termed Insessarea, or Perching Birds. The 

 feet of these are all formed for perching, and 

 their power of grasping is very great ; the 

 toes are slender, flexible, of moderate length, 

 and provided with long, pointed, and slightly 

 curved claws. It includes the Thrushes, 

 Nightingales, and all the sweetest songsters 

 of our groves ; with the Redbreasts, the Spar- 

 rows, Larks, S.v allows, Crows, Kingfishers, 

 Birds of Paradise, and Humming-birds. 

 From including the smaller tribes of Birds, 

 the term I'aeseres is also given to this order. 

 The THIKIJ order is termed Scansores, or 

 Climbers. These have the power of throw- 

 ing one of the fore toes back at pleasure ; a 

 construction which enables them to climb 

 the perpendicular trunks of a tree. Of this 

 order the Parrot tribe and the Woodpeckers 

 are the principal members. The KOUKTH 

 order is termed Easores, or Gallinaceous 

 Birds. It is characterized by the hinder toe 

 being raised above the level of the three 

 anterior ones ; this reduces the power of 

 perching ; but the front toes are united by a 

 slight membrane, and are strong, straight, 

 and terminated by robust, obtuse claws, 

 adapted for scratching up the soil, and for 

 running along the ground ; for which pur- 

 pose they are also furnished with very strong, 

 muscular legs. These birds have the head 

 small in proportion to the body ; and the 

 bill generally short, with the upper mandible 

 somewhat curved. In this order are com- 

 prised the Peacock, the Turkey, the common 

 Cock and Hen, Partridges, Pheasants, Pi- 

 geons, &c The FIFTH order is termed Grnl- 



latorcs, or Waders. To enable them to wade 

 and seek their food in water, along the mar- 

 gins of rivers, lakes, and estuaries, the birds 

 belonging to this order have long and slender 

 legs, and generally bare thighs. Their three 

 front toes are more or less united at the base 

 by a web, and the central toe is often longer 

 and stronger than the rest ; the hind toe is 

 elevated, short, or even sometimes wanting. 



This order comprises the Ostriches, Cranes, 

 Herons, Storks, Snipes, Woodcocks, Bustards, 

 and Plovers. The SIXTH order is termed 

 A'ataturcs, Palmipedes, or web-footed Birds ; 

 and their whole organization is especially 

 adapted for an aquatic life. Their legs are 

 short, and placed behind the centre of equi- 

 librium; their fore toes are united by a thick 

 and strong web or membrane ; and their 

 bodies are covered with a dense layer of 

 down, beneath the outer plumage, which is 

 close, and rendered impervious to the water. 

 The order comprises Swans, Ducks, and 

 Geese ; Auks, Penguins, Pelicans, Petrels, 

 Coots, and Grebes. [See the art. BIBDS.] 



AVICULA. A genus of Conchiferous 

 Molluscs belonging to the order Dimyaria. 

 It is thus defined by Cuvier : "The shell 

 has the valves equal, with a rectilinear 

 hinge, and is often carried out into wings ; 

 the ligament is narrow and elongated ; small 

 dentilations often appear on the hinge, on 

 its anterior part ; and below the angle on 

 the side near the mouth is the notch for the 

 byssus. The anterior abductor muscle is 

 still extremely minute." The foot of the 

 animal is conical, worm-shaped, and rather 

 long. Some very beautiful species of the 

 Avicula are brought from the Indian Ocean, 

 coast of Brazil, New Holland, the Red Sea, 

 &c. The interior of the shell is pearly in 

 the centre : some species have a broad black 

 border surrounding it, and the margin ter- 

 minating in a fringe. The Avicula mnr- 

 garitifcra, or Pearl Oyster, which contains 

 the valuable and elegant substance called 

 Mother-of-pearl, belongs to this genus. [See 

 PKAUI, OYSTER.] 



AVOSET. (Recurvirostraavocetia.} This 

 grallatorial bird, whose great singularity is 

 in the form of its bill, is aquatic, the shores 

 of the ocetm and the banks of estuaries being 

 its favourite haunts. On the shores of the 

 Caspian and the salt lakes of Tartary they 

 are abundant ; they are widely distributed 

 through the temperate climates of Europe; 

 and on the south-eastern coast of England 

 they are occasionally found. The Avoset is 

 about eighteen inches in length ; very erect, 

 and has legs unusually long for its size. 



AVO8BT. (RZCURVTROSTRA AVOCBTTA.) 



The bill, which ia three inches and a half 

 in length, turns up like a hook, in an 

 opposite direction to that of the hawk or 

 parrot, and is flat, thin, sharp, and flexible. 

 The plumage is black and white, tail con- 



