EXOGENS. 139 



pericum, St. John's-woet. Pet. 5. Sta. oo, 3-5-adelph. ; rarely 

 few Kls. yellow, cymose or sol. Boll, rarely fleshy. 160 spec, QJ. 

 herbs, shrubs, often ev. and resinous, widely distributed, both worlds. 

 Numerous in U. S. H. mutilum, boll 1-celled ; Q, low ; H. corym- 

 bosum, %, 2° high, boll 3-celled ; N. Eng. to N. C, W. H. aureum, 

 ev., 2° high, fls. sol., 2' wide, river-banks near mts. Ga., Tenn. H. 

 pyramiddtum, %, 2°-4° high, boll 5-oeUed, N. and W. H. (Elodea) 

 virginicum, l°-2° high; Qj. ; marshes; fls. rose- or flesh-colored, clus- 

 tered ; H. petioldtum, similar, 2° high. Both common. 



Ord. 133. Elatinaceae. Watek-Peppers.— Pis. g, 2-3-4-5- 

 merous, iso- diplostemonous, minute. Boll oo-seeded. Lvs. opp. 

 Small Herbs or Undershrubs, stems creeping or spreading ; often 

 acrid. Ditches, submerged shores, both worlds. 2 gen., 20 spec. 1. 

 Bergia, Water-fire. 14 spec. E. Ind., Java, Cape G. H. 2. 

 Elatine, Watbrwoet. 6 spec , both worlds. E. hexandra, pet. 3, 

 sta. 6. E. Hydropiper, pet. 4, sta. 8 ; Eur. E. americdna, Mud 

 PtfESLANB ; fls. 2-3-merous. U. S. 



Ord. 134. Podostemaceae. — Pis. g or diclinous. Perianth 0, or 

 3-lobed, niarcescent. Sta. 1 or more or oo, monadelph. or free ; stami- 

 nodes present or 0. Ova. and boll 1-3-celled, oo-seeded. Infl. various. 

 Water-plants, with distinct simple or branched stem and lvs., or with 

 all these confluent into fronds ; often resembling Algse and Hepaticie. 

 21 gen., 120 spec, islands of E. Af , but chiefly in S. Am. ; one spec 

 reaching TJ. S. 4 Tribes: Tribe 1. Fls. J> ?. Perianth 0. Ova. 

 1-celled; carpels 2. Only gen. Hydrostachys. 9 spec, Af., Mada- 

 gascar. Tribe 8. Pis. §. 9 gen., 48 spec, both worlds. 1. Podo- 

 stemon. Khiz. various ; often reduced to a disk-like process. Sta. 2. 

 20 spec, both worlds. P. ceratophpUus, lvs. horny, lobes linear. Bot- 

 toms of streams, TJ. S. Tribes. Pis. ^. 9 gen., 52 spec. 1. Api- 

 nagia, 16 spec. ; 2, Ligea, 13 spec ; trop. Am. Tribe 4. Pis. g . 2 

 gen., 11 spec. 1. Terniola, 7 spec. ; trop. Asia. 2. Tristicha, 4 spec. ; 

 trop. Am., Af. 



Pink Alliance. — Pis. reg., usually §. Sep. 2-3-4-5, rarely 6, 

 free or connate. Pet. usually as many, or 0. Sta. as many, or 

 twice as many, rarely fewer or more. Ova. 1-celled or imperfectly 

 2-3-4-5-celled ; placenta central, free, rarely parietal. Emb. usu- 

 ally curved. .Perisperm floury, or rarely fleshy ; rarely 0. 135. 

 Tamariscineae. 136. Portulacacese. 137. Caryophyllaceae. 138. 

 Frankeniaceae. 



Ord. 135. Tamariscinese — Pis. reg. Pet. 5, pink, red, or white, 

 iso- diplostdmonous ; fila. usually connate at base. Boll l-sev.-celled ; 

 sds. hairy. Perisperm present or 0. Lvs. simple, rather fleshy, usu- 

 ally small ; alt., exstip. Shrubs, small Trees. ■ 5 gen., 40 spec, both 

 worlds. Loving sands and open spaces. 3 Tribes : Tribe 1. Pet. 5, 

 connate into a tube. Sds. flattened, bordered with long hairs, or alate. 

 Only gen. Fouquiera. 3 spec, shrubs. Mex. F. splendens, 5°-15° 

 high ; branches reduced to spines, with lvs. sol. or fascicled in their 

 axils. Stem wand-like, crowned with a mass of large, bright-scarlet 

 fls. in panicles. Arizona, Mex. Tribe 2. Pet. distinct. Sds. hairy. 

 2 gen., 11 spec. Small shrubs. 1. Reaumiiria. Pis. sol , showy. 

 Lvs. small. 10 spec, Levant, salt plains, Asia. 2. Holol4chne, 

 monotypic. Cent. Asia. Tribe 3. Pet. almost or quite distinct. 

 Pis. spiked or panicled. 2 gen., 55 spec 1. Myricaria. Ev. shrubs. 



