344 



DICOTYLEDONES. 



small ? -catkins are enclosed in buds, in which they pass the 

 winter ; these buds are situated in the axils of the fallen foliage- 

 leaves, and it is only by their larger size that they may be dis- 

 tinguished from the ordinary foliage-buds. In spring the $ -catkins 

 are easily recognised by their red, projecting stigmas (Fig. 329 A). 

 The cupule the "husk" is tubular, fringed, and envelopes the nut. 

 The leaves are alternate and unsymtuetrical, the external side being larger 

 than the inttrnal ; this is connected with the vernation, the blade being con- 



FIG. 329. Corylusavellana: A branch at the time of flowering with cJ-aud ? -catkins; 

 B (J -flower with subtending-leaf (bract) and two bracteoles ; C the same without t'-e 

 anthers; D view of interior of ?-dichasium shortly after fertilisation; E young fruit 

 with cupule; f similar one with the cupule opened ; G mature ? -fruits; H nut. 



duplicate in the bud ; the stipules are deciduous The bud- scales are formed 

 of stipules, the most internal having a leaf -blade attached to them which is 

 suppressed in the external ones. The cotyledons remain underground on germi- 

 nation. 



Carpinus(0. betulus, Hornbeam). The <$ - and $ -catkins do not 

 appear till the leaves are shooting. The ? -catkin in this 



