356 



SYSTEMATIC BOTANY. 



Distribution. A large Order, the species of which are generally dif- 

 fused j most numerous in tropical South America. 



Qualities and Uses. Some of these plants have enjoyed considerable 

 reputation, having pungent, aromatic, and stimulant qualities. The Aris- 

 tolochicB take their name from the roots of A. Clematitis, longa, rotunda, 

 and others being used as emmenagogues. A. Serpentaria, Virginian 

 Snake-root, is one of the many so-called specifics for Snake-bites, and it 

 is stomachic and tonic. It is worth notice that several species of Aris- 

 tolochia in different countries are considered by the natives valuable 

 remedies in cases of snake-bite. Asarum europteum, Asarabacca, is acrid ; 

 its leaves were formerly much used in a snuff employed in affections of 

 the eyes. Some of these plants are very handsome climbers, with large 

 cordate leaves and striking helmet-shaped flowers ; those of Aristolochia 

 car data are large enough to be used as caps by the Indian boys in the 

 Brazilian woods. The West- African A. Goldieana is equally large. 



SUBCLASS H. GYMNOSPERMIA. 



Phanerogamous plants, with achlamydeous unisexual flowers ar- 

 ranged in spikes, the male flowers consisting of antheriferous scales 

 serially continuous with the leaves and collected in deciduous catkins. 

 Pollen-grains dividing, prior to the emission of the pollen-tube, into 

 secondary cells. The female flower 

 consists either of open carpels (fig. 

 444, A), bearing naked ovules, 

 standing in the axil of a bract, and 

 arranged in persistent cones, or of 

 naked terminal ovules surrounded 

 by a few scales ; seeds perispermic. 

 The endosperm in the embryo-sac 

 is formed previous to fertilization, 

 and produces corpuscula or arche- 

 gonia. Embryo bearing 2 cotyle- 

 dons, which are simple or divided 



into Several lobes - a whorl of 4 Or ^, carpel ofPinus (a, ovules) 



more cotyledons (fig. 444, E) accord- ^^^^ST 



ing to SOme authors. seed) ; D, section of seed, showing 



embryo in endosperm; E, embryo 

 germinating. 



The members of this group are remarkable as forming a bond of union, 



B, scale of 



