LEM 



LEO 



Primates. Generic character : in the up- 

 per jaw four front teeth, the intermediate 

 ones remote; in the lower jaw, six long- 

 er, extended forwards, compressed, paral- 

 lel, and approximated ; tusks solitary and 

 approximated ; grinders several, and 

 sometimes many, sublobated, the fore- 

 most somewhat longer and sharper. 

 This genus of animals is very similar to 

 that of monkeys in the structure of the 

 feet. Some are destitute of a tail, and 

 others have extraordinary long ones. 

 Their manners are very different from 

 those of monkeys, and display nothing 

 of the active mischief and intrusive im- 

 pertinence of that animal. There are 

 thirteen species, of which we shall notice 

 the following: 



L. tardigradus, or the loris. This is 

 of a light brown colour, and of the usual 

 size of a cat. It walks and climbs with 

 great slowness, and is supposed incapable 

 of leaping. Its manners are gentle and 

 interesting, it is extremely susceptible of 

 cold, and when exposed to a strong de- 

 gree of it is agitated with extreme uneasi- 

 ness, and with considerable exasperation. 

 It sleeps from sun -rise to sun-set without 

 intermission, rolled up in the manner of 

 the hedge -hog; it is extremely attentive to 

 cleanliness, licking its full and rich fur 

 with the same assiduity as a cat. Its food 

 consists of plantains, mangoes, and other 

 fruits, and it is scarcely capable of satis- 

 fying itself with grasshoppers when it lias 

 access to them. Many species of insects, 

 indeed, form a repast particularly gratify- 

 ing to it, and the sight of them excites in 

 its look the most glowing animation, and 

 summons to exertion all the energies of 

 its frame. Several of the above particu- 

 lars are taken from an account given of 

 one kept in a state of confinement by the 

 late Sir William Jones. It is a native of 

 various parts of India. 



L. indri, is a native of Madagascar, is 

 the largest of the genus, has a face of a 

 dog-like form, and a fur thick and soft. 

 It has no appearance of a tail : it is very 

 docile, and sometimes trained by the na- 

 tives to hunt various animals. It is three 

 feet and a half in height. 



L. macauco, or the ruffed macauco, is 

 found in some of the Indian islands, and is 

 particularly numerous at Madagascar. 

 It is full of energy and fierceness, and its 

 voice is so strong as to fill the woods with 

 its cries. It will endure captivity, notwith- 

 standing the violent passions it exhibits 

 in a natural state, without discontent or 

 depression, and is stated to be extremely 

 inoffensive, and even sociable in it, with 



those by whom it is surrounded. It pos- 

 sesses neither craft nor malice in it. 



L. catta, or the ring-tailed macauco. In 

 their state of nature these animals are seen 

 in companies of twenty or thirty. They 

 feed on almost every species of fruits, 

 and in a state of confinement, like several 

 others of this genus, will take animal food 

 without any hesitation. They are the 

 most elegant and beautiful species of the 

 whole genus, are lively and gentle, and 

 so agile and elegant in their movements, 

 as to be highly interesting. They delight 

 much in sunshine, and will sit before a 

 fire, like the squirrel, extending towards 

 it their out-spread hands. It inhabits 

 Madagascar, is of the site of a small cat, 

 and resembles that animal in purring. 

 See Mammalia, Plate XV. fig. 1. and 2. 



LENS, dioptrics, properly signifies a 

 small roundish glass, of the figure of a len- 

 til, but is extended to any optic glass, 

 not very thick, which either collects the 

 rays of light into a point, in their pas- 

 sage through it, or disperses them further 

 apart, according to the laws of refrac- 

 tion. 



Lenses have various figures, that is, 

 are terminated by various surfaces, from 

 which they acquire various names. Some 

 are plane on one side, and convex on 

 the other ; others convex on both sides ; 

 both which are ordinarily called convex 

 lenses : though, where we speak accu- 

 rately, the former is called plano-con- 

 vex. Again, some are plane on one 

 side, and concave on the other; and 

 others are concave on both sides ; which 

 are both usually ranked among the con- 

 cave lenses ; though, when distinguish- 

 ed, the former is called a plano-con- 

 cave. Others, again, are concave on 

 one side, and convex on the other, which 

 are called convexo-concave, or concavo- 

 convex lenses, according as the one OP 

 the other surface is more concave, or 

 a portion of a less sphere. It is here 

 to be observed, that in every lens ter- 

 minated in any of the forementioned 

 manners, a right line, perpendicular to 

 the two surfaces, is called the axis of 

 the lens ; which axis, when both sur- 

 faces are spherical, passes through both 

 their centres; but if one of them be 

 plane, it falls perpendicularly upon that, 

 and goes through the centre of the other. 

 See OPTICS. 



LEO, in astronomy, one of the twelve 

 signs of the zodiac, the fifth in order. See 

 ASTRONOMY. 



LEONTICE, in botany, a genus of the 

 Hexandria Monogynia class and order. 



