Family 2. CRASSULACEAE 



By Nathaniki. Lord Britton and Joseph Nklson Rosk^ 



Herbs, or somewhat shrubby plants, mostly fleshy or succulent, with 

 cymose, or rarely racemose or solitary, regular, symmetrical, mostly perfect 

 flowers. Stipules none. Calyx persistent, free from the ovary or ovaries, 

 mostly 4-5-parted or 4-5-lobed. Petals equal in number to the calyx-seg- 

 ments, distinct, or more or less united, usually persistent, rarely wanting. 

 Stamens of the same number or twice as many as the petals : anthers longitu- 

 dinally dehiscent. Receptacle usually with a scale at the base of each carpel. 

 Carpels equal in number to the sepals, distinct, or united below ; styles subu- 

 late. or filiform ; ovules numerous, arranged in 2 rows along the ventral suture, 

 rarely few, or solitary. Follicles 1 -celled, dehiscent along the ventral suture. 

 Seeds minute ; endosperm fleshy ; embryo tere1;e ; cotyledons short, obtuse. 



Calyx inflated ; leaves opposite and often compound. 

 Calyx not inflated ; leaves always simple and rarely opposite. 

 Stamens as many as the calyx-lobes. 



Flowers clustered ; carpels 1 or 2-seeded. 

 Flowers solitary ; carpels several -seeded. 

 Stamens twice as many as the calyx-lobes. 

 Petals 6 to 20. 

 Petals 5 or fewer. 



Carpels one-seeded ; seed erect. 

 Carpels many -seeded ; seeds horizontal. 



Petals usually appendaged at insertion of stamens. 

 Petals not appendaged. 



Corolla strongly 5-angled. 

 Corolla not strongly 5-angled. 



Flowers very large, solitary at the ends of slender 



branches. 

 Flowers smaller, many, variously arranged. 



Flowers axillary, arranged in equilateral racemes, 

 spikes or panicles. 

 Ivcaves opposite, broad, concave on the face. 

 I^eaves alternate, narrow, flat or rounded on the 

 face. 

 Calyx longer than the corolla. 

 Calyx shorter than the corolla. 



Rootstock thick and woody ; flowers large ; 



petals distinct. 

 Rootstock wanting ; flowers minute ; petals 

 united. 

 Flowers terminal, arranged in one-sided racemes or 

 cymes. 

 Petals more or less united. 

 Calyx minute. 

 Calyx conspicuous. 



Flowers in a dense spike. 

 Flowers in cymes or panicles. 



Corolla tubular ; lobes long and erect. 

 Corolla short-campanulate to rotate ; lobes 

 spreading. 

 I^eaves flat, spatulate and obtuse. 

 Ivcaves terete, acute. 



Carpels distinct, erect ; Mexican 



plateau plants. 

 Carpels united at base, spreading ; 

 Pacific Coast plants. 

 Plants with a woody usually 

 branching rootstock. 



1. Bryophyllum. 



2. Tillaea. 



3. TiLLAEASTRUM. 



4. Sempervivum. 



5. Sedella. 



6. Pachyphytum. 



7. Kcheveria. 



8. Oliveranthus. 



9. I^ENOPHYLLUM. 



10. CORYNEPHYLLUM 



11. Clementsia, 



12. ViLLADIA. 



13. Urbinia. 



14. courantia. 



15. DUDLEYA. 



16. GORMANIA. 



17. Altamiranoa 



18. Stylophyllum 



1 Permission has been given by the 

 Rose to contribute to this monograph. 



VOI.UME 22, Part 1, 1905] 



Secretary of the Smithsonian Institution for Dr 



7 



