100 



KEY TO THE FAMILIES AND GENERA 



89. LOASACE^E. 



A. Petals hooded. 



B. Caps. 3-5-yalved at apex, rarely twisted. ... 1. Loasa. 

 BB. Caps, longitudinally 5-10-valved, usually 



twisted apirally 2. Blumen- 



BBB. Caps, narrow, straight, longitudinally 5- [backia. 



valved 3. Scyphanthus, 



A A. Petals not hooded. 



B. Seeds very numerous, arranged in many 



eeries 4. Euenide. 



BB. Seeds few or, if numerous, arranged in 2 



series 5. Mentzelia. 



90. PASSIFLORACE.E. 



A. Hypanthium long; petals and stamens 5 1. Tacsonia. 



AA. Hypanthium short; petals 4-5, rarely 0; 



stamens 4-5 2. Passiflora. 



AAA. Hypanthium medium or short; fls. unisexual. 3. Modecca. 



91. CARICACEJE. 



In cultivation Carica. 



92. CUCURBITACE^:. 

 /. Summary of Tribes. 



A. Series 1. Ovules horizontal 1. CUCURBITA TRIBE, 



AA. Series 2. Ovules erect or ascending, 

 rarely horizontal 



B. Fr. ruptures elastically 2. CYCLANTHERA 



[TRIBE. 



BB. Fr. does not rupture elastically 3. ABOBRA TRIBE. 



AAA. Series 3. Ovules pendulous 4. SICYOS TRIBE. 



77. Key to the Tribes. 

 1. Cucurbita Tribe. 



A. Anther-cella straight, rarely curved, not 



flexuous 1. Melothria. 



AA. Anther-cells flexuous or conduplicate. 



B. Corolla bell-shaped, 5-lobed to the middle 

 or a little below. 



c. Anthers free 2. Sicana. 



cc. Anthers coherent. 



D. Filaments connate 3. Cocdnia. 



DD. Filaments free 4. Cucurbita. 



BB. Corolla rotate and 5-petaled or bell-shaped 



and 5-parted to the base, 

 c. Petals fimbriate or tendril-bearing. 



D. Seeds large, fibrous 5. Telfairea. 



DD. Seeds small, not fibrous 6. Trickoaan- 



cc. Petals entire. [thes. 



D. Hypanthium of male fls. long; anthers 

 coherent in an oblong head, usually 

 included. 

 E. Pistillodes in male fls. 1-3, subulate 



or setiform 7. Gymnopeta- 



EE. Pistillode absent or reduced to a [him. 



gland 



F. Anthers coherent 8. Peponia. 



FF. Anthers free 9. Lagenaria. 



DD. Hypanthium of male fls. short; anthers 

 free or slightly coherent, usually ex- 

 serted. 

 B. Stamens inserted in the mouth of the 



hypanthium. 



F. Scales in bottom of hypanthium . . 10. Thladiantha. 

 FF. Scales in bottom of hypanthium 



2-3 11. Momardica. 



EE. Stamens inserted in hypanthium. 

 F. Male fls. in racemes. 



G. Fr. dry, fibrous, dehiscent by 



lid at top 12. Luffa. 



GG. Fr. fleshy, not fibrous. 



H. Female fls. solitary 13. Ecballium. 



HH. Female fls. racemose or clus- 

 tered 14. Bryonia. 



FF. Male fls. solitary or fascicled. 



G. Sepals somewhat leafy, ser- 

 rate, reflexed 15. Benincasa. 



GG. Sepals awl-shaped, entire, erect. 

 H. Pollen minutely muricate; pis- 



tillode 16. Bryonopsie. 



HH. Pollen smooth; pistillode re- 

 duced to a small gland. 

 i. Tendrils not branched: con- 

 nective usually produced 

 upward beyond locule. . . 17. Cucumis. 

 u. Tendrils 2-3-fid: connec- 

 tive not produced 18. Citrullus. 



2. Cyclanthera Tribe. 



A. Fr. oblique, gibbous, rupturing cla-stically 19. Cyclanthera. 



AA. Fr. not gibbous, opening by 1 or 2 pores at the 



top or by irregular rupture 20. Echirmrystis. 



(Incl. Megnrrhiza.) 



3. Abobra Tribe. 



Anther-cells flexuous; stamens free 21. Abobra. 



4. Sicyos Tribe. 



Fls. 5-merous, monoecious: fr. fleshy 22. Sechium. 



The genera Actinostemrna, Gurania, Herpetospermum, Hodg- 

 sonia and Sicyos are sometimes cultivated. 



93. BEGONIACE^E. 



A, Ovary wholly inferior. 



B. Petals all free 1. Begonia. 



BB. Petals of pistillate fl. grown together 2. Si/mbeg{fi. 



AA. Ovary partly superior S.HiUebrandm. 



94. CACTACE^. 



A. Fl.-tube wanting. 



B. Lvs. large and persistent. 



c. Seeds black and shining 1. Pereskia. 



cc. Seeds white, dull and covered with hairs. 2. Pereskiopsis. 

 BB. Lvs. wanting or minute and caducous. 

 c. Plant epiphytic, spineless: fls. small. 



D. Flowering joints bottle-shaped 3. Hariola. 



DD. Flowering joints not bottle-shaped. ... 4. Khipsalis. 

 cc. Plant not epiphytic, usually very spiny: 



fls. large. 

 D. Petals spreading; filaments much 



shorter than the petals 5. Opuntia. 



DD. Petals erect and closely surrounding 

 the stamens; filaments longer than 



the petals 6. \opalea. 



AA. Fl.-tube present, often much elongated. 



B. Plants epiphytic or nearly so, either flat or 

 3-angled, usually spineless and always 

 with spineless fr. 



c. Sts. 3-angled, bearing small spines at the 

 areoles: ovary and fr. bearing large 



bracts 7. Hylocereus. 



cc. Sts. normally flat, spineless: ovary and 



fr. bearing only minute bracts. 

 D. The sts. weak, divided into many short 

 joints. 



E. Fls. irregular 8. Zygocactus. 



EE. Fls. regular 9. Schlum- 



DD. The sts. stouter than the last, with [bergera. 



elongated joints. 



E. Fl.-tube very short or nearly wanting. 10. Disocactua. 

 EE. Fl.-tube very definite, often much 

 elongated. 



p. Fls. small, diurnal 11. Wittia. 



FF. Fls. large, nocturnal 12. Epiphyllum. 



BB. Plants not epiphytic, never flat, with several 



to many ribs. 



c. Sts. globular or cylindrical, not jointed. 

 D. Plant-body covered with more or less 



definite tubercles: fr. naked. 



E. The plant terminated by a cephaliuml3. Cactus. 

 EE. The plant without a terminal ceph- 



alium. 



F. Without spines except in the seed- 

 lings. 

 G. Plant tumid, without woody 



tubercles. 14. Lophophora. 



GG. Plant with dry prominent 



woody tubercles 15. Ariocarpus. 



FF. With spines on the tubercles. 



G. Tubercles terete or angled, with 



various kinds of spines 16. Afatnmillaria. 



GO. Tubercles flattened, with pec- 

 tinate spines 17. Pelecyphora. 



DD. Plant-body covered with more or less 

 definite ribs: fr. scaly. 



E. Tubercles elongated, finger-like 18. Leuchten- 



EE. Tubercles, if present, always low. \bergia, 



F. Top of plant naked or nearly so. . 19. Echinocac- 



[tus. 



FF. Top of plant very woolly 20. Malacocar- 



cc. Sts, often tall, cylindrical, more-or-less [pus. 



branched, erect or climbing, sometimes 

 low and then always with spiny fr. 

 D. Flowering plants taking on various 

 forms like a cephalium, long hairs or 

 wool, peculiar bristles or spines from 

 near the top. 



E. Ribs of sts. 4-7 21. Lophocereus. 



EE. Ribs of sts. many. 



