661 



<£f)e Er£as*urn nf 3&atmy, 



[last 



Americans, is a shrub growing from four to 

 six feet high, very abundant in some parts 

 of Mexico, forming a dense and almost 

 impassable scrub, particularly on the bor- 

 ders of the Colorado desert, where its luxu- 

 riant growth puts a stop to the drifting 

 saud. It is a sure sign of a sterile soil, 

 for wherever it flourishes little else can be 

 found, and although it gives the scenery a 

 beautifully verdant appearance, its strong 

 creosote-like odour renders it so repulsive 

 that no animal will touch it. Moreover, as it 



can scarcely be made to burn, it is useless 



! even for the purpose of fuel. The resinous 



I matter to which the odour is due abounds 



; in all parts of the plant. The Pimos Indians 



1 collect and form it into balls which they 



kick before them as they journey from 



one point to the other of their trail. It is 



also used iu rheumatism. [A. S.] 



LASEGTJEA. A genus of dogbanes, dis- 

 tinguished by having the calyx five-parted, 

 the divisions oblong, two glands at the 

 base of each ; the corolla shorter than the 

 calyx, its border flve-lobed ; a ring of hairs 

 at the point of origin of the stamens ; and 

 the glands of the nectary five. The species 

 are shrubs or undershrubs, natives of 

 Brazil, having opposite and shortly-stalked 

 leaves, which are cordate and entire ; the 

 racemes of flowers are terminal, and the in- 

 dividual flowers are siipported on stalks 

 which are longer than the linear-lanceolate 

 bracts. [G. D.] 



LASER. (Fr.) Laserpitium. 



LASER CYREXAICUH. The Asa dulcis, 

 Thapsia garganica. 



LASERPITIUM. A genus of umbellifers, 

 distinguished from its allies by the fruit 

 having eight prominent w-ing-like appen- 

 dages. The species are perennial herbs, 

 chiefly found in South-eastern Europe. 

 Some of them are employed as domestic 

 remedies, on account of their possessing 

 some degree of aroma. [G. DJ 



LASERWORT. Laserpitium ; also Thap- 

 sia Laserpitii. 



LASIA. A genus of orontiads, very 

 closely allied to Pathos, but distinguished 

 from that eenus by its sessile spadix and 

 its pendulous ovules. The species are 

 Indian plants, with more or less of a creep- 

 ing habit, thickly beset with strong spines ; 

 and the pinnately-divided leaves have 

 sheathing leaf-stalks. [M. T. M.] 



LASIAGROSTIS. A genus of grasses 

 belonging to the tribe Stipece. The species 

 which were referred to it are described 

 under Stipa by Steudel, who makes Lasia- 

 grostisa. section of that genus. [D. M.] 



L ASIAXDRA. A genus of Melastomacece, 

 consisting of trees or shrubs with four- 

 angled branches, opposite or verticillate 

 entire ribbed leaves, and panicled showy 

 flowers, with five petals and a capsular 

 fruit. There are about forty species, na- 

 tives of tropical America. [J. H. B.] 



LA8IOLEPIS. This genus is stated to 



differ from Harrisonia in its five-parted 

 flowers only, and therefore would be better 

 merged therein. The name is applied to a 

 shrub of the Philippine Islands, with wavy 

 spiny branches and compound leaves, and 

 refers to the hairy scales that are attached 

 to the base of the stamens in this and 

 other genera of Simarubaceee. [M. T. M.] 



LASIOPETALUM. A genus of Stercu- 

 liacece, considered as the type of a tribe 

 exclusively Australian, distinguished by 

 hermaphrodite flowers with the petals 

 either wanting or reduced to small scales; 

 and by the stamens, of which five only 

 bear anthers, and which are only shortly 

 united at the base, or quite free. The 

 genus is characterised in the tribe by 

 anthers opening in terminal pores, and by 

 the calyx not marked with the parallel 

 prominent ribs of Sarotes. It consists' of 

 about twenty-five Australian species, low 

 shrubs, more or less clothed with stellate 

 hairs. The leaves are usually alternate, and 

 more or less toothed or lobed, rarely entire 

 or opposite; and the flowers are in short 

 racemes, with the calyx at first herbaceous 

 and downy, often enlarging as the flower 

 advances, and coloured blue or reddish, so 

 as to assume the appearance of a corolla. 

 A few species occasionally occur in cur col- 

 lections of greenhouse plants. 



LASIOSPERMUM. A genus of South 

 African plants, belonging to the chamomile 

 group of the Composite, and readily recog- 

 nised by the dense rusty wool which com- 

 pletely envelopes the ripe achenes. The 

 three species are erect branching herbs, 

 with pinnatisect leaves, and solitary white- 

 rayed flower-heads, having much resem- 

 blance to those of the feverfew. [A„ A. B.J 



LASIOSTOMA. The name of a cincho- 

 naceous shrub, native of Nqw Ireland. It 

 has sessile flowers in axillary heads ; a cup- 

 shaped calyx limb ; a short-tubed four- 

 parted funnel-shaped corolla ; four anthers ; 

 and a succulent two-celled fruit. The 

 name is also synonymous with Rouhamon, 

 a genus of Loganiacew. [M. T. MJ 



LASTHENIA. A genus of Compositce, of 

 the tribe Relianthece, consisting of three 

 or four Californian or Chilian annuals, 

 with opposite linear leaves, and small 

 flower-heads, with a yellow ray or entirely 

 discoid. The involucre is campanulate, of 

 several united bracts, the receptacle with- 

 out scales, and the achenes with a pappus 

 of about ten chaffy scales or none at all. 

 They grow in wet places, and appear to be 

 uninteresting weeds. 



LASTREA. A large genus of polypodia- 

 ceous ferns of the Aspidinm group, in- 

 cluding all those species in which the veins 

 are free, and the indusium is kidney-shaped. 

 It is one of the three great divisions into 

 which the old genus Aspidium is broken 

 up by modern pteridologists, the others 

 being Nephrodium and Polystichum. The 

 former, which also has reniform indusia, 

 is known from it by the connivently ana- 

 stomosing venation, that of Lastrea being 



