ORN 



ORO 



ORNITHOGALUM, in botany, Star of 

 JBethlehem, a genii* of t he Hexandria Mo- 

 nog} nia class and order. Natural order 

 of" Coronariae. Asphodeli, Jussieu. Es- 

 sential character : corolla six petalled, 

 upright, permanent, spreading above the 

 middle; filaments alternate, -videning at 

 the base. There are thirty-five species. 



ORNITHOLOGY, that branch of natu- 

 ral history which considers and describes 

 birds, their natures and kinds, their form, 

 external and internal, and teaches their 

 economy and uses ; see AVES : also the 

 several orders and genera in the alpha- 

 betical order. Birds are divided, accord- 

 ing to the form <>f their bills, into six or- 

 ders, inz. Accipitres, as eagles, vultures, 

 and hawks : Picae, as crows, jackdaws, 

 humming-birds, and parrots .- Anseres, as 

 ducks, geese swans, gulls : Grallae, as 

 herons, woodcocks, and ostriches : Galli- 

 nae, as peacocks, pheasants, turkies, and 

 common fowls: and Passeres, compre- 

 hending sparrows, larks, swallows, &c. 



Birds are distinguished from quadru- 

 peds by their laying eggs : they are ge- 

 nerally feathered ; some few are hairy, 

 and instead of hands or fore-legs, they 

 have wings. Their eggs are covered by 

 a calcareous shell, and they consist of 

 a white, or albumen, which nourishes 

 the chick during incubation ; and a yolk, 

 which is so suspended within it as to 

 preserve the side on which the little ru- 

 diment of the chicken is situated continu- 

 ally uppermost, and next to the mother 

 that is sitting upon it. The yolk is in great 

 measure received into the abdomen of the 

 chicken, a little before the time of its be- 

 ing hatched, and serves for its support, 

 like the milk ofa quadruped, and like the 

 cotyledons of young plants, until the sys- 

 tem is become sufficiently strong for ex- 

 tracting its own lood out of the ordinary 

 nutriment of the species. 



ORNITHOPUS, in botany, bird's foot, 

 a genus of the Diudelphia Decandria class 

 and order. Neural order of Papiliona- 

 ceze, or Leguminosae. Essential charac- 

 ter : legume jointed, round, bowed. 

 There are five species. 



ORXITHORHYNCHUS paradoxus, in 

 natural history, a singular quadruped, re- 

 markable for its structure. The head is 

 similar to that of a duck, which would 

 lead to the supposition that it belonged 

 to an aquatic bird Both jaws are as 

 broad and low as those in a duck, and the 

 calvaria has no traces of a suture, a^s is 

 generally the case in full-grown birds. 

 In the cavity of the skull there is a consi- 



derably bony falx, which is situated along 

 the middle of the os frontis, and the ossa 

 bregmatis. The mandible of this animal 

 consists of a beak, the under part of 

 which has its margin indented as in ducks, 

 and of the proper instrument for chewing 

 that is situated behind, within the cheeks. 

 Dr. Shaw says it has no teeth, though 

 Mr. Home found, in a specimen examined 

 by him, two small and flat molar teeth 

 on each side of the jaws. The forepart 

 of this mandible, or beak, is covered and 

 bordered with a coriaceous skin, in which 

 three parts are to be distinguished, viz. 

 the proper integument of the beak ; the 

 labiated margins of it; and a curious 

 edge of the skin of the beak. Into these 

 three parts of that membrane numerous 

 nerves are distributed, intended, proba- 

 bly, as the organs of feeling, a sense which, 

 besides men, few mammalia enjoy ; that 

 is, few animals possess the faculty of dis- 

 tinguishing the form of external objects, 

 and their qualities, by organs destined 

 for that purpose, a property very differ- 

 ent from the common feeling, by which 

 every animal is able to perceive the tem- 

 perature and presence of sensible ob- 

 jects, but without being informed, by the 

 touch of them, of their peculiar qualities. 

 Thus the skin in the wings of the bat, 

 and its ear, are supposed the organs of 

 common feeling, by means of which they 

 are enabled to flutter, after being blind- 

 ed, without flying against any thing. The 

 whiskers of many animals appear likewise 

 to serve the same purpose of informing 

 them of the presence of sensible bodies, 

 and hence they have been compared to 

 the antennae of insects. But to return 

 to the ornithorynchus : it is an animal 

 which, from the similarity of its abode, 

 and the manner of searching for food, 

 agrees much with the duck, on which 

 account it has been provided with an 

 organ for touching, viz. with the integu- 

 ment of the beak richly endowed with 

 nerves. This instance of analogy in the 

 structure of a singular organ of sense 

 in two species of animals, from classes 

 quite different, is a most curious circum- 

 stance in comparative physiology, and 

 hence the ornithorhynchus is looked up- 

 on as one of the most remarkable pheno- 

 mena of zoology. There are two species, 

 both inhabitants of New-Holland. 



OROBANCHE, in botany, broom-rape, 

 a genus of the Didynamia Angiospermia 

 class and order. Natural order of Per- 

 sonatae. Pediculares, Jussieu. Essential 

 character : calyx bifid ; corolla ringent ; 

 capsule one-ceiled, two-valved, many- 



