134 SOUTH AFRICAN FLOWERING PLANTS. 



in the tribe Pomece, where the calyx becomes superior, 

 and the resulting fruit inferior. 



The single carpel of the peach contains two ovules 

 (Fig. 53, III., IV.), but as a rule one only becomes a 

 kernel or seed (VI.). The carpel becomes the fruit (V.), 

 consisting of three distinct layers, the skin, or eincarp, 

 the edible flesh, or mesocarp, and the stone, or endocarp, 

 the three together making the pericarp. There is no 

 wild species of the genus Prio'nus in South Africa, 



but one tree Py'geum, is in 

 Kaffraria. 



Tribe, Rubeae. — This con- 

 tains one genus only, Bu'bus 

 — the blackberry and rasp- 

 I. ^ berry. There are five species 



'Lj,-;|arsi:lVslcSS in the Colony. The recepta- 

 Singe rupe. cular tubc takcs the form of 



a little trough. The fruit is a dense head of miniature 

 drupes called drupels (Fig. 54, I.). II. is a vertical 

 section of a drupel, showing the embryo. 



Trihe, Potentilleae. — One European species, Foten- 

 til'la supi'na, has been introduced. The fruit consists 

 of a cluster of achenes, as seen in the strawberry. 

 But as the edible part of this is not the fruit at all, 

 the whole is called a pseudocarp, or " false fruit " ; the 

 achenes upon it are the real fruits. The following is 

 the description of the details of Fig. 55 : — 



The trifoliate leaf will be seen to have a pair of 



