BIRTHWORT TRIBE 253 



by nurserymen as a stock upon which to graft the dehcious D. Indica 

 of greenhouses. Woods ; not unfrequent. — Fl. March. Shrub. 



2. D. Mezereiim is occasionally found in situations where it is 

 apparently wild ; but it is not considered a native ; its purple, 

 fragrant flowers appear before the leaves, and are sessile on the 

 branches ; the leaves are not evergreen ; berries red. 



Natural Order LXX 



SANTALACE^. — Sandat.-wood Trtbe 



Perianth attached to the ovary, 4- or 5-cleft, valvate when in 

 bud ; stamens as many as the lobes of the perianth, and opposite 

 to them ; ovary i-celled ; style i ; stigma often lobed ; fruit, a 

 hard, dry drupe. The plants of this group are found in Europe 

 and North America, in the form of obscure weeds ; in New Holland, 

 the East Indies, and the South Sea Islands, as large shrubs, or small 

 trees. Some are astringent, others yield fragrant wood. Sandal- 

 wood is the produce of Santalmn album, an East Indian tree, and 

 is used both medicinally and as a perfumer. In New Holland and 

 Peru the seeds of some species are eaten. The only British plant 

 belonging to this tribe is — 



I. Thesium (Bastard Toad-flax). — Characters given above. 

 (Name of doubtful origin.) 



I. Thesium {Bastard Toad-flax) 



1. T. linophylhim (Bastard Toad-flax). — The only British species. 

 A rather small plant, with a woody root ; nearly prostrate stems, 

 6-12 inches high ; very nairow, pointed leaves, and leafy clusters 

 of whitish flowers. Chalky hills in the south of England ; not 

 common. — Fl. July. Perennial. 



Natural Order LXXI 



ARISTOLOCHIACEiE.— Birth- WORT Tribe 



Perianth attached to the ovary below, tubular above, with a 

 wide mouth ; stamens 6-12, inserted on the ovary ; ovary 3 to 

 6-celled ; style i ; stigmas rayed, as many as the cells of the ovary ; 

 fruit 3- to 6-celled, many-seeded. Herbs or shrubs, often climbing, 

 with simple leaves, and solitary, axillary flowers, very abundant in 

 the warmer parts of South America, but rare elsewhere. The 

 plants of this Order are generally bitter, tonic, and stimulant. 

 The dried and powdered leaves of Asarabacca (Asarum Ettropaiim) 

 are used in the preparation of cephalic snuffs, exciting sneezing, 

 and giving relief to headache and weak eyes. Virginian Snake- 

 root [Aristolochia serpentaria) and other allied species are used as 



