ROSIFLORJ:. 



461 



FIG. 602. Diagram of 

 Prunus virginiana. 



Rubtis-species : Raspberry (R. idteus), Cloudberry (R. chamcemorus), Blackberry 

 (R. fruticoms), etc. ; of .Fra/jana-species (F. vesca, collina, grandijiora, etc). 



Order 2. Amygdalacese. Trees or shrubs with rosaceous 

 flowers ; leaves simple with caducous stipules ; a regular, perigy- 

 nous flower, the receptacle being partly 

 thrown off by a circular slit ; sepals 5, 

 petals 5 stamens 20-30; gynwceum simple, 

 formed of 1 carpel (hence oblique, Fig. 502), 

 with terminal style and 2 pendulous ovules, 

 ripening into a drupe (Fig. 503).^- The 

 leaves are penninerved and frequently have 

 glands on the stalks and edges ; thorns 

 (modified branches) often occur, i.e. dwarf- 

 branches, which, after producing a few 

 leaves, terminate their growth in a thorn 

 {e.g. Prunus spinosa). The vernation of the foliage-leaves varies in the 

 different genera ; in the Almond, Peach, Cherry, and Bird-Cherry they are 

 folded; in the Apricot, Plum, Sloe and Bullace, rolled together. In some the 

 flowers unfold before the leaves (Amyydalus, Armeniaca}. That the gynoeceum 

 is formed of 1 carpel is evident in this as in other instances (e.g. in the 

 Leguminosae, which are closely related to this order), from the fact that the 

 carpel is oblique, and has only one plane of symmetry, and similarly in the 

 fruit there is a longitudinal groove on one side which indicates the ventral 

 suture. It is only exceptionally that both ovules are developed. In abnormal 

 instances more than 1 carpel is developed. 



A. FRUIT HAIRY: Amygdalus {A. communis, Almond-tree) has 

 a dry pulp which is detached irregularly, when ripe, from the 

 wrinkled, grooved, ovoid and 

 somewhat compressed stone. 

 Persica (P. vulgaris, Peach-tree) 

 differs from the Almond in hav- 

 ing a juicy pulp, not detachable 

 from the stone, which is deeply 

 grooved and has pits in the 

 grooves (Fig. 603). (The name 

 of the genus is derived from Persia, 

 though it is a native of China). 

 Armeniaca (A. vulgaris, Apricot) 

 has a hairy, velvety fruit, but 

 the stone is smooth and has two 

 ribs along one of the edges ; the 

 pulp is juicy. (The generic name has been given on the incorrect assumption 

 that it was a native of Armenia ; its home is China.) 



FIG. 503. Fruit of the Peach. The pulp is 

 cut through so that the stone is visible. 



