322 PANICLE CYME YERTICILLASTER. [BOOK i. 



mentioned are to be considered as reductions of the spike or 

 raceme. Those which are now to be described are decompo- 

 sitions, more or less irregular, of the raceme. 



The first of these is the panicle and its varieties. The 

 simple panicle differs from the raceme in bearing branches of 

 flowers where the raceme bears single flowers, as in Poa 

 (fig. 78.) j but it often happens that the rachis itself separates 

 into irregular branches, so that it ceases to exist as an axis, as 

 in some Oncidiums; this is called by Willdenowa deliquescent 

 panicle. When the panicle was very loose and diffuse, the 

 older botanists named it a juba ; but this is obsolete. If the 

 lower branches of a panicle are shorter than those of the 

 middle, and the panicle itself is very compact, as in Syringa, 

 it then receives the name of thyrsus. 



Suppose the branches of a deliquescent panicle to become 

 short and corymbose, with a centrifugal expansion indicated 

 by the presence of a solitary flower seated in the axils of the 

 dichotomous ramifications, and a conception is formed of what 

 is called a cyme. This kind of inflorescence is found in Sam- 

 bucus, Viburnum, and other plants (fig. 85.). 



If the cyme is reduced to a very few flowers, such a dis- 

 position has been called a verticillaster by Hoffmansegg. 

 (Verzeichniss z. Pflanz. Cult.) ii. 203.) It constitutes the 

 normal form of inflorescence in Labiates, in which two verti- 

 cillasters are situated opposite each other in the axils of 

 opposite leaves. By Linnseus, the union of two such verticil- 

 lasters was called a *>erticillus or whorl ; and by others, with 

 more accuracy, a verticillus spurius or false whorl. Link terms 

 this inflorescence a thyrsula ; but Hoffmansegg's name seems 

 preferable. 



The following tabular view of the differences among inflo- 

 rescences will probably tend to render the above remarks 

 more clear : 



Flowers not placed on stalks, 



arranged upon a lengthened axis, 



which is permanent, Spike, Locusta, Spadisc. 



which is deciduous, Catkin. 

 arrangedupon a depressed axis, Capitulum, Glomerulus. 



