MIXED INFLORESCENCE. 



163 



and the cyme is called scorpioidal or helicoidal (&/!, a spiral, and 

 lllog, form) or gyrate.* It is seen in the forget-me-not (fig. 253). 



341. Instances of both kinds of floral expansion occur occasionally 

 on the same plant. Thus, in Compositse, the heads of flowers taken 

 as a whole, are developed centrifugally, the terminal head first; while 

 the florets, or small flowers on the receptacle, open centripetally, those 

 at the circumference first. So also in Labiata?, the different whorls of 

 inflorescence are developed centripetally, while the florets of the verti- 

 cillaster are centrifugal. Sometimes this mixed character presents 

 difficulties in cases such as Labiatae, where the leaves, in place of 

 retaining their ordinary form, become bracts, and thus might lead to 

 the supposition of all being a single inflorescence. In such cases, the 

 cymes are described as spiked, racemose, or panicled, according to 

 circumstances. Fig. 254 represents a panicled cyme of Privet, in 



* Schleiden says that this inflorescence is simply a unilateral raceme, having centripetal ex- 

 pansion. 



