CHAP, v.] RELATIONSHIP AMONGST PLANTS. 167 



It has already been stated that in primitive flowers, as 

 buttercups, poppies, etc., the pistil is situated highest up, 

 or terminal, on the central axis of the flower, and per- 

 fectly free from the other whorls ; when this is the case, 

 the ovary is said to be superior. If the flower of a snow- 

 drop, gooseberry, or Fuchsia is examined, the calyx and 



Fig. 50. 

 carpel. 



Pod of the pea, illustrating a fruit composed of a single 



corolla will be found to originate from the top of the 

 ovary, the latter being apparently lowest down on the 

 axis of the flower ; in such cases the ovary is described 

 as inferior. It must be understood that there are not 

 two primitive types of flower structure, one with the 

 ovary superior, the other having the ovary inferior ; but 



