X GENERAL KEY TO THE PpLYPETALOUS ORDERS. 



truded as to appear axial in a septate ovary, in Mesemhryanthemum becoming 

 parietal through secondary changes in the ovary) : stamens mostly definite, 

 less frequently oc ; filaments free or slightly united at the base, hypogynous 

 or in many FicoidecB and the genus Fouquieria distinctly perigynous. 



++ Embryo (with rare exceptions) peripheral and curved about more or less 

 copious albumen : herbs or rarely shrubs. 



18. CARYOPHYLLACE^E. Flowers perfect or through abortion polygamo-dioe- 

 cious, commonly dichlamydeous ; floral envelopes regular, 4-5-merous. Calyx either 

 gamosepalous (Tribe I.) or of distinct sepals. Petals as many as the sepals or 

 calyx-lobes (rarely feweror none), either unguiculate and often coronate (Tribe T.) 

 or sessile and unappendaged, either entire or more or less deeply bifid or laciniate. 

 Stamens as many or twice as many as the petals or rarely of some irregular num- 

 ber but never more numerous. Carpels 2 to 5; styles distinct or (Tribe III.) 

 united below ; ovary free, completely unilocular or partially septate from the base ; 

 embryo curved about the albumen (straight in Dianthus and Tunica). Leaves 

 opposite or verticillate, entire or nearly so. Scarious stipules sometimes present. 



19. FICOIDE^. Calyx regular, persistent (in N". American species), 4-5-lobed or 

 -divided, free or more or less adnate to the ovary. Petals (modified stamens) 

 in Mesemhrijnnthemum numerous, narrow, in other N. American genera wanting. 

 Stamens either hypogynous or perigynous, few or many, when as many as the 

 calyx-divisions alternate with them, when numerous often slightly united near the 

 base into phalanges. Cells of the ovary (except in Cypselea and sometimes in 

 Trianlhemci) 2 or more, with as many styles or free stigmas ; placentse axial or 

 basal, but in most species of Mesembryanthemuni soon appearing parietal through a 

 strong secondai-y radial or at length cupulate development of the base of the 

 ovary. Fruit capsular or (in Tetrarjonin) indehiscent. Leaves opposite (when 

 often unequal), pseudoverticillate, or (in Tetragonia) alternate. Scarious stipules 

 sometimes present. 



20. PORTULACACE^. Flowers regular or nearly so, perfect. Sepals (except in 

 some species of Leivisia) 2, free or more or less adnate to the ovary, mostly ovate 

 or orbicular. Petals mostly 5, sometimes fewer or none, very rarely more numer- 

 ous, free or sometimes (in Montia, Cahjptridium, and Calandrinia) more or less con- 

 nate at the base, often deliquescent or fugacious. Stamens as many as the petals 

 and opposite them or sometimes more numerous and indefinite, but rarely fewer. 

 Ovary superior or (in Portulaca) half inferior, 1-celled ; stigmas (2 to) .3 ; ovules 

 (1 to) 3 to X, on central placentae. Fruit a circumscissile or (2-)3-valved capsule. 

 Leaves entire, opposite (rarely whorled) or alternate, often fleshy. Stipules when 

 present scarious, often laciniate. 



++ ++ Seeds hairy or wing-appendaged, with straight embryo and little or no 

 albumen. 



21. TAMARISCINEtE. Flowers regular, perfect (rarely in foreign species dice- 

 cious). Sepals 4 or 5, distinct or nearly so, imbricated. Petals as many, free or 

 (in Fnuqideria) united into a 4-.5-lobed tube. Stamens (4 to) .5 or 10 onx, inserted 

 beneath and outside of a hypogynous or nearly hypogynous disk. Ovary free, uni- 

 locular, but in Foriquieria almost divided by the strongly intruded placentae ; styles 

 and valves of the capsule 3 to 5. 



