RHODODENDRON: BIRCH 95 



Euonymus europceus, L. Spindle Tree (Fig. 93). 



00 Capsule woody , 5-valved ; seeds numerous, 

 small , not arillate. 



Rhododendron. 



(b) Fruit indehiscent and often seed-like. 



[The fruit characters of seed-like achenes are recognised 

 in the presence of stigmatic scars, traces of perigones, more 

 complex coverings, &c.] 



(i) Fruit with only one seed. [For (ii) 



see p. 114.] 

 [Since the one-seeded condition frequently arises by 



abortion of one or more other ovules, exceptions may 

 occur in which two seeds have reached maturity e.g. 

 Tilia.] 



(a) Fruit free of any accessory investing [For (p) 

 cupule. 



* Fruits shed from between the complex [For (**) 

 scales of a more or less elongated catkin. see p ' 97t -' 



t Catkin pendulous, cylindroid ; its scales 

 3-lobed, tough, deciduous ; fruits flat, 

 winged, 2 mm. long, in threes. 



Betula alba, L. Birch (Fig. 94). The scales of the 

 catkin are composed of the bract and two bracteoles of 

 the axillary group of three flowers, fused into a common 

 trilobed whole (see Vol. ill. p. 233); this and the inde- 

 hiscent, one-seeded fruit, with a broad papery wing on 

 each side, at once distinguish Birches from Willows and 

 Poplars. 



Betula nana, L. is similar, but the catkin and fruits 

 smaller. 



ft Fruiting catkins erect, woody, branched and 

 cone-like, persistent ; the scales more or less 

 distinctly 5-lobed; achenes not winged, in 

 pairs. 



