APPENDIX A 



635 



The variability of Rosaceous flowers is illustrated by such examples. A 

 striking feature is the diversity of origin of the succulent pulp, which gives 

 value to their fruits. In the Strawberry it arises from the convex receptacle ; 



Fig. 487. 



Drupe of Cherry. (After 

 Figuier.) 



Fig. 488. 



Grouped drupels of the Raspberry. 

 (After Figuier.) 



in the Rose from the concave receptacle ; in the Apple and Pear partly from 

 the receptacle, partly from the carpels ; in the Raspberry it is from the middle 

 layer of the tissue of the very numerous carpels (Fig. 488) ; in the Cherry 

 and Plum from the corresponding tissue of the single carpel. The Almond of 

 shops is the seed taken from the drupe of Amygdalns. 



ORDER : LEGUMINALES. 



This is one of the largest and most important Orders of Plants, and it is 

 cosmopolitan. It is characterised by its gynoecium, which consists of a single 

 carpel, ripening as a Legume, or Pod, as in the Pea. It is divided into three 

 Families : the Mimoseae, which are the most primitive, having flowers of 

 radial symmetry, as in Mimosa and Acacia ; the Caesalpineae, which have 

 zygomorphic flowers, as in the Tamarind, or Cassia ; and the Papilionaceae, 

 or Pea-flowers. The last of these only are represented in the British Flora. 

 The Order yields most varied products of importance : food-stuffs, timbers, 

 drugs, and dyes, etc. 



Family : Papilionaceae. Examples : Trefoil, Pea. 



(30) The Bird's Foot Trefoil (Lotus comiculatus, L.) forms many straggling 

 branches from a central root-stock. The leaves have green " stipules " which 

 are really basal pinnae, and three distal lobes, hence its name. The flowering 

 branches are leafless, but bear distally a leafy bract and a radiating group of 

 flowers. Each flower is strongly zygomorphic, its plane of symmetry being 

 vertical and median, as it is in all of the Papilionaceae (Fig. 489). It is com- 

 posed thus : 



Calyx, sepals 5, gamosepalous, inferior, the odd sepal being anterior. The 

 calyx-tube gives mechanical support to the internal parts, and is slightly 

 widened in a perigynous manner. 



Corolla, petals 5, polypetalous, inserted separately on the slightly widened 

 receptacle, i.e. perigynous. The petals alternate with the sepals. The 



