460 CLASSES 



CLASS XIX. SYNGENESIA. Anthers united by their 

 edges into a cylinder. Flowers compound, or collected 

 into heads. ORDERS 5. 



ORDER 1. JSauALis. Florets of the disk and ray all 

 fertile, being furnished with stamens and pistils. 



A. Florets all ligulate, or strap-shaped. 

 Ex. Leontodon, (Dandelion,) 



Lactuca, (Lettuce,) 

 Hieracium, (Hawkweed.) 



B. Florets all tubular and erect, forming nearly a level 

 top. 



Ex. Eupatorium, (Boneset,) 



Bidens, (Burr-marigold.) 

 ORDER 2. SUPERFLUA. Florets of the ray obsolete ; those 



of the disk with pistils and stamens ; all fertile. 

 Ex. Artemisia, (Wormwood,) 



Gnaphalium, (Life Everlasting.) 



C. Florets, radiate and ligulate. 

 Ex. Aster, (Starwort,) 



Solidago, (Golden rod,) 

 Senecio, (Groundsel,) 

 Anthemis, (Mayweed.) 



ORDER 3. FRUSTRANEA. Florets of the disk with 

 stamens and pistils, and fertile; those of the ray with 

 stamens only, and barren. 

 Ex. Helianthus, (Sun-flower,) 



Coreopsis, ( Tickseed-sun-flower,) 

 Rudbeckia, (Rudbeckia.) 



ORDER 4. NECESSARIA. Florets of the disk with sta- 

 mens, but no pistils, and therefore barren ; those of 

 the ray with pistils only, and fertile. 

 Ex. Calendula, (Marigold,) 



Iva, (False Jesuit's Bark.) 

 ORDER 5. SEGREGATA. Besides the common involucre, 



each floret has its distinct perianth. 

 Ex. Elephantopus, (Elephant 1 s foot,) 



Echinops, (Globe Thistle.) 

 CLASS XX. GYNANDRIA. Stamens placed on the 



pistil or germen. ORDERS 7. 



ORDER 1. MONANDRIA. One Stamen. 



A. Anther, terminal, erect ; pollen granular, cohering 



by an elastic thread. 

 Ex. Orchis, (Orchis,) 



Habenaria, (Habenaria.) 



