262 NATURAL SYSTEM OF JUSSIEU, 



1. Chicoracece. — Florets ail ligulate and united or fer- 

 tile. Leaves alternate, flowers commonly yellow. 

 Leontodon and Lactuca are examples. 



2. CinarocephaLa. — Florets all tubular. Leaves alter- 

 nate, often spinous, colours of the flowers various. 

 Carthamus, Arctium and Centaurea are examples. 



3. CorymbifercB. — Flowers mostly radiate, the discal 

 floret3 being tubular, and those of the ray being ligu- 

 late. This is a very extensive order, embracing 

 more than fifty genera within the limits of the United 

 States. Helianthus and Aster are examples. 



Class 7. Flowers Monopetalous* Corolla epigy nous . 

 Anthers distinct. Calyx raonophyllous. Corolla 

 monopetalous. Stamens determinate. Filaments 

 inserted into the coroOa. Germen simple, in- 

 ferior. 



1. Dipsacece. — Capsule monospermous, resembling a 

 single seed. Embryo without albumen. Radicle 

 superior. Stern herbaceous. Leaves opposite. 

 Flowers aggregate, enclosed in a common polyphyl- 

 lous calyx. Dipsacus and Scabiosa are examples. 



2. Rubiacece. — Stamens four or five, alternating with 

 the segments of the corolla. Fruit usually two 

 naked seeds ; or two celled and polyepermous. Em- 

 bryo small, slender, laterally involved in a large cor- 

 neous albumen. Leaves entire, verticillate or op- 

 posite with intermediate stipules. Galium, Housto- 

 nia, Mitchella and Gardenia are examples. 



3. Caprifolia. — Stamens usually five, alternating with 

 the divisions of the corolla. Fruit a berry or cap- 

 sule, usually crowned by the persistent calyx. Em- 

 bryo in a cavity at the summit of a fleshy albumen. 

 Leaves opposite and without intermediate stipules'- 



