ARTIFICIAL KEY TO THE FAMILIES. lix 



Perianth 2-seriate, the segments of both corolline, rarely sub- 

 herbaceous, and if so then with inferior, 1 -celled ovary ; or if 

 only the inner series corolline, then its segments much larger 

 than those of the outer series ; ovary syncarpous ; or if 

 perianth 1 -seriate, then ovary 1 -celled and either scapigerous 

 herbs with corolline perianth or submerged marine plants with 

 calycine perianth : 



Seeds very small, often very minute ; albumen 0, or scanty : 

 Outer perianth-segments calycine, inner corolline or ; 

 stamens 3, 6, 9 or 15, rarely 1-2 by suppression, some often 

 converted into staminodes ; aquatic, usually submerged 

 herbs with regular, often 1 -sexual flowers 



CXLVI. HYDROCHARITACEAE. 



Perianth-segments of both series corolline ; flowers 

 2-sexual : 



Flowers regular ; anthers 6 or 3, sessile or subsessile on 

 the perianth, not united to the gynoecium ; ovary 

 3-celled ; albumen of seeds scanty ; small annual herbs 



CXLVII. BtJRMANNIACEAE. 



Flowers irregular, usually markedly so by the modifi- 

 cation of one segment of the inner series to form a lip ; 

 androecium and gynoecium confluent as a column 

 bearing 1, rarely 2, sessile or nearly sessile anthers, ovary 



1-celled CXLVIII. ORCHIDACEAE. 



Seeds conspicuous, with copious albumen : 



Ovary inferior, 3-celled ; or if 1-celled, then either flowers 

 very irregular or leaves pinnatifid : 



Flowers very irregular ; outer perianth-segments 

 calycine ; perfect stamen 1 with 5 staminodes or rarely 

 5 or 6 perfect with 1-0 staminode ; seeds often arillate : 

 Both series of perianth united, tubular or spathaceous ; 

 anthers 2 -celled : 



Inner perianth-series funnel-shaped below, 3-lobed 

 above ; style embraced below the stigma by the 

 single anther ; ovary sometimes 1-celled ; fruit 



usually capsular CXLIX. ZINGIBERACEAE. 



Both perianth-series spathaceous, entire or toothed ; 

 stamens free, 5 perfect with 1-0 staminode, rarely 6 

 perfect ; fruit berry-like, elongate-oblong 



CLII. MUSACEAE. 



Outer perianth-series of 3 free, equal or subequal 

 segments, inner 3 united into a tube below ; single 



