BOTANY. 471 



leaves, always alternate, are often spinous, as well as the scales of 

 the calyx or bractese. 3. The Corymbiferce, Discoidece or Radiatce, 

 have received these different names as indicating their appearance. 

 All have flowers disposed in a corymb, in which the centre or disc 

 is often less elevated than the circumference, of which the ligulate 

 corollae form rays ; but their principal distinction is in the dispo- 

 sition of the flowers. This numerous family is subdivided into two 

 sections ; Jirst, into those genera with the receptacle naked ; and 

 secondly, those with the receptacle chaffy. 



The other monopetalous flowers with the corolla epigynous and 

 with distinct anthers have all a particular calyx. They are often 

 aggregated or capitate in a sort of spurious calyx formed by the 

 floral leaves. Some have but a single seed crowned by the interior 

 calyx, which is persistent, and the leaves of these are always oppo- 

 site, as the Dipsacece. Others have two naked heads, or many in- 

 closed in a pericarp ; and these have the corolla tubular, and ver- 

 ticillate or opposite leaves united by stipulse, as the Rubiacece. In 

 others the corolla is very deeply cleft, so as almost to appear poly- 

 petalous, and the leaves never furnished with stipulse, as the Capri- 

 foliacece. 



XIII. The Dicotyledonous plants with monoclmous and polype- 

 talous flowers are divided into three large orders, as seen in the 

 tabular view, according to the insertion of the stamina above, be- 

 low, or around the pistil. The Epigynous flowers, although in great 

 number, form but two families, of which one, the Aralice, compre- 

 hends the genera Aralia and Panax, both exotic, and of which the 

 flowers have many styles. The other family bears the name of 

 Umbelliferce. They have received this name from the disposition 

 of their flowers in an umbel or umbrella form. The greater por- 

 tion are biannual herbs, with a channeled fistules stem, or filled 

 with a loose, cottony tissue. The flowers are generally hermaphro- 

 dite, with five stamina and five petals, and their fruit is composed 

 of two seeds united. They are further distinguished as the flowers 

 are simple, or the particular peduncles not subdivided, and bearing 

 but one flower ; or as compound, when each primary peduncle which 

 radiates from the general stem is itself subdivided into secondary 

 umbels or umbellulae. At the origin of the peduncles there are often 

 found floral leaves or bracteae forming a kind of collar or involucrum. 

 When these are below umbellulae or smaller umbels it is termed 

 involucdla. Many subsidiary divisions are used to arrange the ge- 

 nera of this extensive family. 



XIV. The Dicotyledonous, irionoclinous, polypetalous plants 

 with stamina placed below the ovary are very numerous, and have 

 been arranged into many families. 1. Ranuiiculacece : This large 



