182 



PRIMULACE^i. 



[CLASS 



OBSERVE the stamens opposite to the lobes of the 

 corolla : the i-celled ovary with a central placenta wholly 

 free from the sides of the ovary from its first origin : the 

 ovary half-inferior in Samolus : the fruit dehiscing trans- 

 versely in Pimpernel (Anagallis) : the absence of a 

 corolla in Glaux. In this genus the calyx is coloured 

 like a corolla. 



Compare the inflorescence of Primrose, Cowslip (P. 

 veris), and Chinese Primrose (P. sinensis), the latter a 

 common parlour plant. It is essentially similar in all, 

 but in Primrose the peduncle is arrested close to the 

 stock, so that the pedicels only appear. Sometimes it 



FIG. 124. Vertical section cf flower of Primula sivnsis. 



lengthens out, bearing an umbel of flowers, as in Cow- 

 slip. In Chinese Primrose the peduncle does not ter- 

 minate in a single umbel, but is prolonged beyond it, 

 bearing a second or third umbel ; all the flowers, 

 excepting those of the terminal umbel, becoming, in 

 consequence, whorled. 



In Cyclamen the embryo has but I cotyledon ; in some 

 species of Cyclamen this cotyledon enlarges, persists, and 

 becomes a " foliage-leaf." The "tigellum" of the embryo 

 enlarges, forming a thick perennial corm, from which 

 leaves and flowers annually rise. It is called Sowbread 



