THE GENUS (ENOTHERA. 



[part 



shaped, and of large size. The cal3'x of CEno- 

 thera biennis^ the common Evening or Tree 

 Primrose, consists of four sepalsgrowing together 

 in the lower part, so as to form a long tube (a 

 v^fy. So), and with tlie upper part or limb gene- 

 rally in two segments (^), which are bent quite 



Fig. 33. — The Evexin'g Primrose (CEnoUicra biennis). 



back when the corolla expands, and which may 

 be easily divided with a pin into four. There 

 are four petals in the corolla (c), and they are 

 placed so as to wrap over each other at the base. 

 The calyx is lined with the dilated receptacle, 

 and in this lining are inserted the filaments of 

 the eight stamens (as shown at d) ; the stamens 



