8 PRELIMINARY OBSERVATIONS. [parti. 



only one of these coverings, and when this is the 

 case it is called by modern botanists the calyx, 

 though it may be coloured like a corolla; and 

 sometimes the calyx and corolla are of the same 

 colour, and so mixed as hardly to be distin- 

 guished from each other, as in the crocus and 

 the tuhp ; in which case the divisions are called 

 the segments of the perianth. 



