Elatine. ELATINACE^. 281 



valves alternate with the dissepiments ; and oblong straight or curved seeds, the 

 crustaceous testa filled or nearly so by the cylindraceous embryo ; the cotyledons 

 short and thick. Only two genera. 



1. ELATINE. Flowers 2-4-merous. Sepals membranaceo-herbaceous, obtuse, without 

 midrib. Capsule globose, membranaceous. Mostly aquatic annuals or sub-perennials, 

 glabrous. 



2. BERGIA. Flowers 5-merous. Sepals pointed or aciite, with thickened midrib and 

 scarious margins. Capsule ovoid, of firm texture. Terrestrial, some suffrutescent, usually 

 pubescent. 



1 . EL ATlNE, L. Waterwort. (Old Greek and Latin name for some 

 herb, from iXarr], a fir-tree, absurdly applied by Linnaeus to this genus because a 

 whorled-leaved species had been named Potamopithys, i. e. River Pine.) — Aquatic 

 and subaquatic annuals or sub-perennials by rooting from the nodes ; ours all 

 depressed little plants, an inch or two high, mostly creeping by rooting from the 

 nodes, occurring both in aquatic and terrestrial forms ; with small flowers in the 

 axils of the entire leaves, when under water not rarely fertilized without opening ; 

 fl. summer. — Gen. no. 335 ; Seubert, Monogr. in Nov. Act. Nat. Cur. xxi. 38 ; 

 Benth. & Hook. Gen. i. 162 ; Gray, Proc. Am. Acad. xiii. 361. 



§ 1. Crypta, Seubert, I.e. Flowers 2-3-merous, 2-3-'androus : thin capsule 

 often bursting irregularly, the delicate portions evanescent or fragile; seeds 

 slightly curved : leaves simply opposite, in ours sessile or subsessile and the 

 flowers sessile. — Crypta, Nutt. Jour. Acad. Philad. i. 117 (§ Crypta, Gray, 

 Gen. 111. i. 220), answers to this section more extended. 



E. triandra, Schk. Leaves oblanceolate or nearly lanceolate with gradually tapering base : 

 petals and stamens commonly 3, but sepals often only 2 : seeds ascending over the whole 

 thickened axis of the capsule, more slender than those of tlie following. — Handb. i. 345, t. 

 109^ f. 2 ; Seubert, 1. c. t. 2, f. 1-8 ; Gray, Proc. Am. Acad. xiii. 361, 362. — Ponds, Illinois 

 and Nebraska, E. Hall; Yellowstone Lake, Tweedy. Rare in Ainer., widely distributed in 



. Old World. 



E. Americana, Arn. Leaves obovate, very obtuse (1 to 3 lines long) : flowers 2-merous 

 or occasionallv 3-merous throughout, in aquatic form rarely opening and the ovules and 

 seeds mainly basilar, in terrestrial form flowers expanding and witli larger rose-colored 

 petals, the seeds more axile ; these cylindraceous, a third line long, slightly curved, clathrate- 

 sculptured with 9 or 10 longitudinal lines and 20 to 30 cross-bars. — Edinb. Jour. Nat. & 

 Geogr. Sci. i. 431 ; Torr. & Gray, Fl. i. 203 ; Gray, Gen. 111. i. 220, t. 95, & Proc. Am. Acad. 

 1. c. E. minima, Fisch. & Mey. Linnsea, x. 73 ; Seubert, 1. c. t. 2, f. 9, 10. E. Clinfoniana, 

 Peck, Rep. Reg. Univ. N. Y. xxii. 52, terrestrial form. Peplis Americana, Pursh, Fl. i. 238. 

 Crjipta minima, Nutt. Jour. Acad. Philad. i. 117, t. 6, f. 1, & Gen. App. ; Torr. Fl. N. & 

 Midd. States, i. .32. 1 Leptrina antumnalis, Raf. Jour. Phys. Ixxxix. 96 (1819). — In mud 

 and shallow water. New England i to "Virginia and Brit. Columbia, along the Rocky Moun- 

 tains to Colorado and the Sierra Nevada to S. California. (Mex,, Austral., E. Ind., &c.) 



E. brachysperma, Gray. Leaves oblong or oval with narrowed base: flowers mostly 

 2-merous : seeds short-oblong, straightish, barely quarter line long, sculptured in 6 or 7 

 longitudinal lines with 10 or 12 cross-bars. — Proc. Am. Acad. 1. c. ; Wats. Bot. Calif, 

 ii. 436. — Illinois and Texas, Hall, Bebb, &c., to Arizona, Leinmon, and coast '^ of California, 

 Anderson, Orcutt ; chiefly terrestrial. 



1 Also northward into Brit. America from Tadousac, I)r. G. G. Kennedy, and Hull, Quebec, 

 Mncoun, to Vancouver Isl., Macoun. 



2 Also on plains in the interior of the state, ace. to Greene, Fl. Francis. 113. Add syn. Alsinastrum 

 brachysiiermum, Greene, Man. Baj'-Rcg. 62. 



