ORDER 21. CAEYOPHYLLACE^E. 253 



ORDER XX. ELATINACE^E. WATER PEPPERS. 



Serbs small, annual, with opposite leaves and membranous stipules. FIs. minute 

 axillary. Sepals 2 5, distinct or slightly coherent at base, persistent. Petals by- 

 pogynous, as many as the sepals. Sta. equal in number to, or twice as many as 

 the petals. Anlh introrse. Ova. 2 6-celled. Stigmas 2 5, capitate ; placenta in 

 the axis. Fr. capsular. Seeds numerous, exalbuminous. 



Genera 6, species 22, found in every part of the globe, growing in marshes. The following i? 

 our only northern genus. 



ELATINE, L. (Gr. ekdrr], fir ; from the resemblance of the slender 

 leaves of some species.) FIs. 2 4-merous. Stigmas sessile, minute. 



E. Americana Arn. MUD PURSELANE. St. diffuse, procumbent, striate, rooting 

 from the joints, with assurgent branches ; Ivs. lance-oval or obovate, obtuse, 

 entire ; sty. ; sep., pet., sta., stig. 2 3, as well as the cells and valves of the 

 capsule ; stip. very minute. A little mud plant, on the borders of ponds and 

 rivers, TJ. S. FIs. axillary, sessile, solitary. Cor. minute, closed. Jl.^ Sept 

 (Crypta minima Nutt. Peplys Americana Ph.) 



ORDER XXI. CARYOPHYLLACE^E. PINKWORTS. 



Herbs with swollen joints, opposite, entire leaves, and regular flowers. Sepals 

 4 or 5, persistent, distinct, or cohering into a tube. Petals 4 or 5, unguiculate or 

 not, bifid or entire, mostly removed from the calyx by a short internode of the torus, 

 sometimes wanting. Stamens distinct, twice as many as the petals, rarely an equal 

 number or fewer. Ovary often stipitate ; styles 2 5, stigmatous the whole length 

 of the inner surface. Fr. a 1 -celled capsule (or imperfectly 2 5 celled), opening at 

 the top, or loculicidal. Sds. numerous; embryo curved around the albumen. (See 

 Figs. 70, 209, 258, 296, 299, 300, 313, 392.) 



The Pinkworts as constituted by Endleicher and others, and above characterized, comprehends 

 four Suborders, and in the aggregate 83 genera and 11SO species. They are in general destitute 

 of active properties. A few of them are valued as highly ornamental in cultivation, but tho 

 greater part are insignificant weeds abounding in waste sandy tracts throughout the temperate 

 tones. 



Leaves furnished with dry, membranous stipules. SUBORDER II. (J) 

 Exstipulate. Capsule 1-celled, 3 00-seeded. Petals rarely absent. SUBORDER !.() 

 Capsule 1-celled, 1-seeded. 'Petals none. SUBOKDF.R III. (h) 

 Capsule completely 3-cellcd. Petals none. SUBORDER IV. (k) 



* Sepals united into a tube. Petals long-clawed. Ovary stiped. TRIBE 1. (a) 



* Sepals distinct or nearly so. Petals subsessilc. Ovary sessile. TRIBE 2. (b) 

 T Styles or stigmas 5. Capsule 1-cclled, OO-seedcd. TRIBE 3. (e) 



T Styles 2 or united into 1. Utricle 1-seeded. TRIBE 4. (f ) 



SUBORDER I. CARYOPHYLLIN'EJE. 



al. SILENE^E. Calyx with scale-like bractlets at base. Styles 2 DIANTHUS. 1 



Calyx bractless. Styles 2. Capsule 4- toothed when open.SAPONARiA. 2 



Styles 3. Capsule 6-toothed when open. SILENI:. 3 



Styles 5. Caps. 10-toothed. . . AGP.OSTEJIM A, 4. . LYCHNIS. 5 

 b 2. ALSINE.<E. Petals 2-parted (sometimes wanting in No. 6.) (c) 



C Styles 5. Capsule opening at the top by 10 teeth CKRASTIUM. 6 



C Styles 3. Capsule opening deeply by 6 half- valves.. .STELLARIA. 7 

 Petals undivided (sometimes wanting in No. 9). (d) 



d Valves of the capsule 3, each 2-toothed. Styles 3 \T.EXARIA. S 



d Valves, &c., entire. Styles 3, always fewer than sepals ALSINE. 9 



Styles 4 or 5, always as many as sepals. .SAGINA. 10 



Styles 3 &5. Disk large, 10-lobed.Ho.vKEXYA. II 



SUBORDER II. ILLECEBRINE^E. 



a 8. BPERGULEJ3. Styles 5. Petals white. Lvs. linear, whorled Si ERGULA. 12 



Styles 3 and 5. Petals red. Lvs. linear, opposite SPERGULARIA. 13 



.Styles Sin all the flowers. Stipules ovate. Lvs. in 4's.PoLYCARPON. 14 

 Stip. multifid. Lvs. opp. . . STIPULICIDA. 15 



