357 



LASTREA. 



LAURACE^E. 



358 



L. Stter has bipinnate quite glabrous leaves ; leaflets lanceolate or 

 oval, quite entire, mucronate, sometimes confluent, and then 3-lobed; 

 the leaves of the involucre and involucels linear-lanceolate, slightly 

 awned, acuminate, the wings of the fruit narrow. It is a native of 

 the mountains of the middle and south of Europe. The root is 

 extremely bitter, and yields an aromatic resinous substance which 

 has been supposed to be the Silpbion or Laser of the ancients. 

 [SILPHIUM; LASER.] L. Siler is supposed by Fraas to be identical 

 with the AiywTimfc of Dioscorides, 3, 51. Sibthorp found this plant 

 in Greece. L. gummiferum, a native of Portugal and Spain, also 

 yields a gum-resin. There are several other species of Laterpitium 

 described, and many of them yield a gum-resin, which is one of the 

 secretions of the order to which they belong. 



(Lindley, Flora Medica ; Don, Dichlamydeoui Plant! ; Fraas, 

 Synopsis Plantarum Flora Clatsica.) 



LASTREA, a genus of Ferns, belonging to the tribe Aspidiece. It 

 hag a reniform indusium attached by the sinus, the veins distinct 

 after leaving the midrib, and not uniting with those of the adjoining 

 pinnule. [AgPlDiUM.] 



L. Thelypteris, Marsh Fern, has pinnate fronds, linear-lanceolate; 

 pinnse slightly downy, but without glands. The lobes are entire, 

 blunt, appearing acute on the fertile fronds from the revolute margins ; 

 the rbi/ome creeping. It is found in marshy and boggy places in 

 Great Britain. 



L. Oreopterit, Sweet Mountain-Fern, has pinnate fronds, the pinna; 

 linear-lanceolate, pinnatifid, glandular beneath, gradually decreasing 

 from about the middle of the frond to near the root ; lobes oblong, 

 flat ; sori marginal. 



L. Filix mat, Male Fern, is known by its subbipinnate fronds, obtuse 

 and serrated pinnules, sori near the central nerve, lateral nerves 

 forked. It is found on woods and banks in Cumberland and Yorkshire. 



L. crittata has linear-lanceolate subbipinnate fronds, short triangular 

 oblong pinnatifid pinna;; pinnacles serrated, the lowermost lobed, 

 and almost piunatifid ; lateral nerves of the lobes with several 

 branches. It is found in bogs and boggy heaths in Norfolk, Notting- 

 hamshire, and Cheshire. 



Z. tpinulota has the segments of the fronds serrate, and spinose 

 mucronate ; stipes clothed with broad roundish concolorous scales. 



L: rigida has its fronds triangular, lanceolate, bipinnate, and 

 glandular ; segments of the pinnules 2- to 5-toothed, not spinulose ; 

 stipes clothed with long-pointed concolorous scales. It is found at 

 Inglebrough, Arnside Knot, and near Settle in Yorkshire. 



Z. dilatata is distinguished by the stipes being clothed with long 

 pointed scales, with a dark centre and diaphanous margin ; the 

 fronds are arched, often drooping, convex. It is found in woods and 

 on banks in Westmoreland. 



Z. Foenitecii has a triangular bipinnate frond ; the stipes clothed 

 with long, narrow, laciniated, concolorous scales. It is the Nephrodiutn 

 Fcenitecii of Lowe. The frond is elongate, triangular, concave below. 

 It is sweet-scented, and is found in damp places in Great Britain, 



LATA'NIA, a genus of Palms of the tribe Sorauinea; of Martius, 

 which has been so-called from the name, Latanier, of one of the 

 species Z. Sorbonica, indigenous in the Isle of Bourbon. The other 

 species, Z. rubra, a much smaller plant, and remarkable for its red- 

 coloured leaves, is a native of the Mauritius. Both are moderate 

 sized, with all the leaves of a palmate fan shape, the flowers yellow, 

 and the drupes yellowish coloured. The leaves, like those of other 

 palms, are employed by the natives for covering their huts, as well as 

 for making fans and umbrellas. The leaf-stalks are split and 

 employed for making baskets, sieves, &c. The fleshy part of the 

 fruit is astringent, and the kernel bitter and purgative ; and the sap 

 is possessed of remarkable antiscorbutic properties, according to the 

 statement of French authors. 



LATHYRUS, a genus of Plants belonging to the natural order 

 Leyummota:, and the tribe Vicifix. It has a campanulate fl-cleft calyx, 

 the two upper lobes the shortest. Stamens diadelphous; style 

 flattened, dilated at the apex, shaggy or downy in front; legume 

 oblong, many-seeded, 2-valved ; seeds globose or angular. The species 

 are usually climbing herbaceous plants; the stipules half-sagittate; 

 leaves cirrhose ; leaflets 1, 3 pairs ; peduncles axillary. 



L. Aphaca is a common European field plant. It is a little smooth 

 pale glaucous green annual, branching from the root into several 

 weak stems, either procumbent or climbing by means of numerous 

 alternate simple tendrils, each of which springs from between a pair 

 of large stipules of a broad arrow-shape, nearly entire. There are 

 no true leaves or leaflets, except that now and then near the root, a 

 pair of an elliptical shape on one or two rudiments of tendrils, very 

 rarely on a real tendril, may be observed, but these soon wither away. 

 The flowers are solitary on long simple stalks, accompanying some of 

 the tendrils, small, drooping, and lemon-coloured. The bracts are in 

 jmirs, n<- 1-xhaped. The teeth of the calyx long and lanceolate, ribbed. 

 The legume about an inch in length, somewhat cylindrical, smooth, 

 with about six round seeds, which are somewhat narcotic, and produce 

 excessive headache if eaten abundantly in the ripe state. When 

 young and green they may be eaten without inconvenience, like green 

 peas. It is a British species. 



//. Cicera is a native of Spain. It is a nearly smooth plant, with 

 spreading winged stems ; the leaflets 2, linear-oblong ; tendrils 



3 to 4 ; stipules half-sagittate, lanceolate, somewhat toothed, ciliated, 

 the length of the petiole, which is not membranous at the edge ; 

 peduncles 1-flowered, longer than the stipules ; bractlets very small ; 

 calycine segments lanceolate, leafy, almost three times as long as the 

 tube ; corolla red ; legumes broad, oblong, irregularly reticulated, 

 channelled, not winged at the back ; seeds 3-cornered, somewhat 

 truncate, brown, and smooth. The seeds are poisonous, and the 

 flour with which they are ground up is rendered unfit for use. 



There are 9 British species of this genus mentioned by Babington 

 in addition to Z. Aphaca. 



L. Nisiolia is known by its leaf-like petioles, without leaves or 

 tendrils, and with minute stipules. 



Z. hirssidus has linear-lanceolate leaflets, and globose tubercular 

 seeds. 



Z. pratemie has many-flowered peduncles, and subulate calyx-teeth ; 

 the flowers are of a bright yellow ; the hilum small and oblong. It 

 is found in moist meadows and pastures. 



Z. iylvestris has a winged stem, many-flowered peduncles, the leaves 

 of one pair of linear-lanceolate, or lanceolate leaflets; calyx teeth 

 triangular, subulate ; seeds compressed, smooth, and half surrounded 

 by the hilum. The broad-leaved varieties often pass for Z. latifolius. 



L. latifoliut is known by the leaves consisting of one pair of 

 elliptical pointed leaflets; the seeds tubercular, rugose, one-third 

 surrounded by the hilum. It is a doubtful native. 



Z. palutlru has the leaves composed of 2 or 3 pairs of linear- 

 lanceolate acute leaflets; the seeds a quarter surrounded by the 

 hilum. 



' Z. maritimut has an angular stem, not winged ; the leaves of 3 to 

 8 pairs of oval leaflets ; stipules large, oval, cordate, hastate. It is a 

 rare plant found on pebbly sea shores. 



Z. mncrurhizus is known by its simple winged stem ; the leaves 

 having two or three pairs of oblong or lanceolate blunt apiculate 

 leaflets, without tendrils; cylindrical pods. It is the Oi-obua tuberoaua 

 of Smith. 



L. niger has a branched stem, not winged ; the leaves of 3 or 6 pairs 

 of lanceolate or oblong leaflets, without tendrils; stipules linear, 

 subulate, the lower ones arrow-shaped. 



(Babington, Manual ; Lindley, Flora Medica.) 



LATIALITE. [HAUINE.] 



LATROB1TE, a Mineral, which occurs crystallised and massive. 

 Primary form a doubly oblique prism. Cleavage parallel to all the 

 primary planes. Colour pale rose-red or pink. Fracture uneven. 

 Hardness 5-0 to 6'0. Lustre vitreous. Translucent. Specific gravity 

 272 to 2-80. Found at Amitok Island, Labrador, and in Finland. 

 Analysis by Gmelin : 



Silica 44-65 



Alumina 36-81 



Lime 8'29 



Potash 6-58 



Oxide of Manganese 3*16 



99-49 



LAUMONITE, a Mineral belonging to the group of Hydrous 

 Silicates of Alumina. It occurs in oblique rhombic prisms. The 

 cleavage is parallel to the acute lateral edge ; also massive, with a 

 radiating or divergent structure. The colour is white, passing into 

 yellow or gray. Lustre vitreous. Hardness 3'5 to 4'0. Specific gravity 

 2'3. It contains 



Silica 

 Alumina 

 Lime 

 Water . 



48-3 

 22-7 

 12-1 

 16-0 



-99-1 



It is found exclusively in America. The best specimens are 

 obtained at Peter's Point, Nova Scotia. 



LAUNCE. [AMMODYTES.J 



LAURA'CE-iE, Laurels, a natural order of Apetalous Exogens, con- 

 sisting entirely of trees and shrubs, inhabiting the warmer parts of the 

 world, and in most cases aromatic, on which account several are men- 

 tioned in works on officinal plants. The best known species in Europe 

 is Laurut nobilit, the Sweet Bay, a beautiful evergreen, whose fragrant 

 leaves are commonly employed to flavour confectionary. [LAURUS.] 

 Other products of the order are cinnamon and cassia; sassafras, whose 

 bark has great reputation in North America as a powerful sudorific ; 

 Pichurim beans, an indifferent substitute for nutmegs ; and finally, 

 not to mention other useful substances, camphor, obtained by the 

 Chinese from the Camphora officinarvm by means of dry distillation. 

 [CAMPHOKA.] 



In general it may be expected that the trees of this order are 

 valuable as aromatics and stimulants, although but a comparatively 

 small number has yet been brought into use. They are known by the 

 peculiar structure of their flowers, which have no corolla, stamens in 

 one or several rows, often in part gland-like and sterile, a simple 

 1-celled superior 1-seeded ovary, and especially by the anthers bursting 

 with recurvtd valves. [CINNAMOMUM; LAOBUS; NBCTANDKA; BEN- 

 ZOIN; SASSAFRAS.] 



There are 46 genera and 450 species of this natural order. Its- 

 position is near Thymdacea and Catsythacea. 



