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A TEXTBOOK OF THEORETICAL BOTANY 



Fig. 1545. — Saxitiai;u longifolia. Cambridge University 

 Botanic Garden. 



II. Francoideae 



Perennial herbs with radical leaves and flowers in spikes or racemes on 

 naked scapes. Flowers tetramerous. Gynoecium with four loculi. Francoa, 

 Tetilla. 



III. Hydrangeoideae 



Shrubs with generally opposite leaves. Flow^ers usually pentamerous 

 with epigynous stamens and a gynoecium with three to five loculi. Deutzia 

 (Fig. 1546), Hydrangea, Philadelphus. 



IV. Pterostemonoideae 



Shrubs with alternate stipulate leaves. Flowers pentamerous, androe- 

 cium of ten stamens. Gynoecium with five loculi, with four to six ovules 

 on axile placentas. Pterostemon. 



V. Escallonioideae 



Trees or shrubs with simple alternate leathery leaves. Stamens of 

 equal number to the petals. Gynoecium either superior or inferior, ovules 

 indefinite in number. Brexia, Escallonia, Phyllonoma, Polyosma, Itea. 



