328 INDEX. 



Onza, or ounce, of the panther kind ; the onza of Linnaeus, 

 ii. 431. 



Ophidium, the gilt-head, by sailors called the dolphin, its de- 

 scription, v. 119. 



Opossum, an animal in North and South America, of the size 

 of a small cat, and of the monkey kind ; its description ; the 

 young when first produced are very small, and immediately 

 on quitting the real womb, they creep into the false one, 

 but the time of continuance is uncertain ; Ulloa has found 

 five young hidden in the belly of the dam, alive and cling- 

 ing to the teat, three days after she was dead ; chiefly sub- 

 sists upon birds, and hides among the leaves of trees, to 

 seize them by surprise ; cannot run with any swiftness, but 

 climbs trees with great ease and expedition ; it often hangs 

 by the tail, and for hours together, with the head downwards, 

 keeps watching for its prey ; by means of its tail, flings itself 

 from one tree to another, hunts insects, escapes its pursuers ; 

 eats vegetables as well as animal substances ; is easily tamed, 

 but a disagreeable domestic from its stupidity, figure, and 

 scent, which, though fragrant in small quantities, is un- 

 grateful when copious; during its gestation, the bag in which 

 the young are concealed may be opened and examined with- 

 out inconvenience ; the young may be counted and hand- 

 led ; they keep fixed to the teat, and cling as firm as if they 

 made a part of the body of the mother, iii. 323, &c. 



Orb, description of the sea-orb, also called the sea-porcupine ; 

 is absolutely poisonous if eaten, v. 109. 



Ore of tin is heavier than that of other metals ; the basest ores 

 in general the most beautiful to the eye, i. 66. 



Organs of digestion, in a manner, reversed in birds, iv. 13. 



Ortolan, a bird of the sparrow kind, iv. 256. 



Osprey, its flesh is admired by many, and when young an 

 excellent food, according to Bellonius, iv. 68. It chiefly 

 lives upon fish, 76. Its distinctive marks, 78. 



Ostracion, a fish of the cartilaginous kind, is poisonous, v. 109. 



Ostrich, manner in which the Arabians hunt them, ii. 182, and 

 ir. 49. An Arabian horse of the first speed scarcely out- 

 runs them, ii. 182. The greatest of birds ; makes near ap- 

 proaches to the quadruped class ; its flesh proscribed in 

 Scripture as unfit to be eaten ; its description ; appears as 

 tall as a man on horseback ; brought into England above 

 seven feet high; surprising conformation of its internal parts; 

 a native only of the torrid regions of Africa; not known to 

 breed elsewhere than where first produced ; places they in- 

 habit ; the Arabians say it never drinks ; will devour leather, 

 glass, hair, iron, stones, or any thing given; in native de- 

 serts leads an inoffensive social life. Thevenot affirms the 

 male keeps to the female with connubial fidelity ; thought 

 much inclined to venery ; some of their eggs weigh fifteen 



