CASTANEACE^. 



231 



rise to fifteen. All are formed of a free slender filament, inserted in 

 the centre of a floral receptacle, rarely under a rudimentary gynge- 

 cium, and of an exserted, bilocular, extrorse anther, dehiscing by 

 two longitudinal clefts.^ The female catkin (fig. 184) is ordinarily 

 thicker, more rigid and bearing a smaller number of flowers.^ They 

 have a gourd-like receptacle, with a neck more or less elongate, and 

 the cavity of which entirely shelters the inferior ovary (fig. 185, 186), 



Quercus Robur. 



Fig. 184. Female inflorescence. 



Fig. 183. Male inflorescence. 



Fig. 187. Fruit. 



whilst its superior opening bears a calyx often having six ^ divisions 

 imbricate in two series, more rarely a lower or higher number.* 

 The ovary is surmounted by a style with three branches of variable 

 form,^ often thickened, dilated and obtuse at their stigmatiferous 

 extremity, entire or slightly lobed. It encloses three ^ cells, more or 

 less incomplete, either above or below, containing each two colla- 

 teral, descending ovules, more or less completely anatropous, with 

 micropyle exterior and superior.'^ The ovary is, at its base, sur- 

 rounded to a variable height by a cupule entirely covered externally 

 with bractlike prominences of very variable dimensions (fig. 185, 

 186), not unfrequently nearly smooth or traversed by folds or wrinkles 

 nearly horizontal or oblique.^ This cupule persists thickening and 

 hardening around the fruit (fig. 187) which it may even completely 



^ The pollen is " round ; threefold ; in water 

 three linear bands" (H. Mohl, Ann. Sc. Nat. 

 ser. 2, iii. 312). 



- Not unfrequently two or even a single one. 



2 From four to nine. 



•* Here and there are abnormal flowers with 



one or more sterile or fertile stamens, either 

 within or without the perianth 



^ Rarely linear, erect (see p. 233). 



* Sometimes two or four. 



7 With double coat. 



^ The morphological signification of this 



