388 



MEDICAL BOTANY. 



the leafstalks of C. cardunculus. Among the more common culinary ve- 

 getables are Tragopogon porrifolius or Salsify, Chicorium endivia or 

 Endive, C. intybus or Succory, the root of which is used so largely to adul- 

 terate coffee ; Lactuca sativa or Lettuce, &c. 



The Asteracese are divided into sub-orders : 1. Tubuliflorce ; 2. Labia- 

 tiflorce ; and 3. Liguliflorce. 



Fig. 179. 



Sub-orders of Asteraceae. 

 1. Liguliflorae. 2, 3. Tubuliflorae. 4, 5. Labiatiflora. 



1. Tubuliflorae. Corolla tubular and regularly 4 — 5-lobed, either in all the flowers, 

 or in the central ones only ; those of the margin presenting a ligulate or strap-shaped 

 corolla. 



Tribe 1. Eupatoride^e. — Style of the perfect flowers cylindraceous ; branches or lobes 

 elongated, obtuse or clavate, externally pubescent or papillose towards the summit ; 

 etigmatic lines obscure, terminating near the middle. Anthers never caudate. 



Liatris. — Schreber. 



Heads few, many-flowered. Scales of involucre few or numerous, imbricate not striate. 

 Receptacle naked. Corolla tubular, 5-lobed, lobes usually elongated. Branches of style 

 much exserted, cylindraceous, obtuse. Achenia nearly terete, tapering to the base, 

 about 10 ribbed. Pappus of 15 — 40 plumose or barbcllate bristles. 



A large genus of North American herbs, mostly with simple stems and a 

 tuberous root, and alternate or scattered, usually lanceolate or linear and en- 

 tire leaves, with a rigid margin. The heads of flowers are in a long spike 

 or raceme, rarely corymbose ; they are usually of a purple colour, but some- 

 times white. The root in a large proportion of them is a naked tuber, im- 

 bued with a tcrebinthinate substance. A number of them have been indis- 

 criminately employed as medical agents, especially in domestic practice, and 



