LEG 



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L E 



tinct, monadelphous or diadelphous; 

 ovarium superior, one-celled, many 

 seeded, style and stigma simple; 

 fruit a legume, or, rarely, a drupe; 

 seeds occasionally with an arillus ; 

 embryo, exalbuminous; cotyledons,, 

 either remaining under ground, or 

 appearing above, in germination ; 

 leaves compound, stipulate, alter- 

 nate; leaflets stipulate; inflores- 

 cence usually axillary, but various. 

 One genus of this order, Deta- 

 rium, has a drupe for its fruit, and 

 Mimosa has a perfectly regular 

 corolla. 



The order Leguminosae is most 

 important to man both for its beauty 

 and utility. The pea, bean, harico, 

 vetch, liquorice, clover, sainfoin, 

 lucerne, tamarind, indigo, gum 

 arabic, &c., &c., belong to it. Gen- 

 erally, the order is innocent, if not 

 wholesome; but some few genera 

 are poisonous. 



LEGUMINOSI'TES. The name given by 

 Mr. Bowerbank to certain fossil 

 seeds found in the London clay. 

 He describes them as seeds of true 

 Leguminosa, the pericarps of which 

 are not known. These seeds pre- 

 sent, both in form and structure, 

 all the characteristic features ob- 

 servable in numerous recent genera 

 of true leguminous fruits. Mr. 

 Bowerbank has described eighteen 

 species, and says it would, however, 

 - be extremely difficult, if not im- 

 possible, to identify these seeds 

 with those of existing genera, sup- 

 posing them to belong to such, 

 without the assistance of their per- 

 icarps. 



LEGU'MINOUS. Belonging to the order 

 Leguminosas; bearing pods; hav- 

 ing a legume for a pericarp. 



LEHM. A German word, being another 

 name for the deposit now common- 

 ly known as loess. See Loess. 



LE'MMING. The Lapland marmot. 

 The lemming has short ears and a 

 tail, with the toes of its fore-feet 

 peculiarly adapted for digging. 



Cuvier places the lemming in the 

 order Ilodentia, class Mammalia. 

 Bones of the lemming have been 

 found fossil in a breccia at Cette. 



LE'MNIAN EAETH. A mineral found 

 in the island of Lemnos, in the 

 Egean Sea, whence its name. It 

 is also called Sphragide, from 

 a(f)pa^, sigillum, a seal. It is of a 

 reddish colour and has a soapy feel. 

 It is dug once a year, with much 

 ceremony, in the Isle of Lemnos. 

 It was formerly used in medicine ; 

 when impressed with the seal of 

 the Grand Seignior, it was sold 

 under the name of terra sigillata. 



LENS, (lens, a lentil, Lat. lentille, 

 Fr. lente, It.) So named from its 

 resemblance to a seed of the lentil. 

 A transparent substance having its 

 two surfaces so formed that the 

 rays of light, in passing through it, 

 have their direction changed. Of 

 lenses there are various sorts; a 

 spherical lens, is a sphere, all the 

 points in its surface being equally 

 distant from the centre. A double 

 convex lens, is a solid formed by two 

 convex spherical surfaces, having 

 their surfaces on opposite sides of 

 the lens. When the radii of its two 

 surfaces are equal, it is said to be 

 equally convex; when the radii are 

 unequal, it is said to be unequally 

 convex. A plano-convex lens, is a 

 lens having one of its surfaces con- 

 vex and the other plane. A double 

 concave lens is a solid, bounded by 

 two concave spherical surfaces, and 

 may be either equally or unequally 

 concave. A plano-concave lens, is a 

 lens one of whose surfaces is con- 

 cave and the other plane. A men- 

 iscus, is a lens one of whose surfaces 

 is convex and the other concave, 

 and in which the two surfaces meet 

 if continued. A concavo-convex lens, 

 is a lens one of whose surfaces is 

 concave and the other convex, and 

 in which the two surfaces will not 

 meet if continued. 



LENTICE'LL^:. The name given by 



