ARTIFICIAL KEY TO THE FAMILIES. Ixi 



as long as and lying in a central canal in the 



albumen CLX. PONTEDERIACEAE. 



Outer perianth-series calycine, inner corolline ; embryo 

 marginal or only partly enclosed in the albumen 



CLXII. COMMELINACEAE. 



Inflorescence in a dense head supported by rigid, dark- 

 brown, imbricating bracts ; perianth 3-merous, outer 

 segments bract-like, scarious, one conspicuously larger 

 than the other 2, inner segments corolline 



CLXI. XYRIDACEAE. 



Perianth-series both calycine ; or if the inner series corolline, 

 then its segments not larger than those of the outer ones ; or if 

 the perianth 1 -seriate, then calycine and either terrestrial plants 

 or aquatic herbs with 1-carpelled or apocarpous ovary ; or 

 perianth reduced to scales or bristles or altogether wanting ; or 

 if perianth-segments of inner series corolline and larger than those of 

 the outer series, then aquatic herbs with apocarpous ovary ; ovary 

 always superior : 



Perianth regularly 2-seriate, 3-merous ; ovary syncarpous ; 

 seeds albuminous ; or if ovary apocarpous and seeds without 

 albumen, then in erect, scapigerous herbs with conspicuous, 

 whorled, paniculate or umbellate flowers : 



Both perianth-series calycine, rigid or herbaceous ; ovary 

 syncarpous ; albumen copious : 



Grass-like herbs with slender, linear or terete leaves, or 

 leaves reduced to sheaths ; flowers in bracteate cymes ; 

 fruit a 3-valved capsule ; embryo enclosed in the albumen 



CLXIII. JUNCACEAE. 



Trees or shrubs, sometimes climbing by hooked thorns, 

 with flabellate-plicate or pinnatisect leaves ; flowers in 1 

 or more sheathing spathes ; fruit indehiscent ; embryo in 

 a small pit near the circumference of the albumen 



CLXIV. PALMACEAE. 



Perianth of a single series of calycine, valvate segments, or of 

 2 series with the outer herbaceous and the inner corolline ; 

 ovary apocarpous ; albumen : 



Leafless, saprophytic herbs without chlorophyll ; perianth 

 1 -seriate, 3-8-partite or -lobed ; flowers insignificant, 

 monoecious or dioecious, in terminal corymbs or racemes 



CLXIX. TRIURIDACEAE. 



Leafy, green, marsh- or water-plants, often with milky 

 juice ; perianth 2-seriate, outer 3 herbaceous, inner 3 



