154 HYDR0PHYLLACE.3J. Hydroplyllum. 



irregular, leaving the thin dissepiment with the central placenta. Styles 2. Corolla 

 nearly rotate, imbricatsd in the bud. Seeds very numerous, with fleshy albumen. 

 Leaves all alternate, simple and entire. 

 14. HYDROLEA. The only genus. 



1. HYDROPHtLLUM, Tourn. Waterleaf. (Formed of tftoop, 

 water, and cpvhXov, leaf, a name of no obvious application.) — - North- American 

 herbs ; with petioled ample and lobed or divided alternate leaves, and cymose 

 clusters of violet-blue or white flowers, in early summer. 



§ 1. Htdeopiiyllcm proper. Perennial, with fleshy horizontal rootstocks : 



calyx naked at the sinuses, except occasionally in the last species. 



* Leaves pinnatifid or pinnate : at least the calyx and inflorescence hispid. 



-I— Peduncles shorter than the petioles, generally shorter than the mostly dense inflorescence: 

 anthers short-oblong. 



H. macrophyllum, Nutt. Hispid or rough-hirsute, stout, 2 or 3 feet high : lower 

 leaves commonly a foot long ; the divisions oval or oblong, obtuse, 2 or 3 inches long, in- 

 cisely toothed ; the upper ones confluent : stout peduncles commonly forked : cymes very 

 dense : calyx white-hispid, not deeply parted ; its divisions triangular-subulate, tapering 

 gradually from the broad base, loosely spreading : corolla dull white, half an inch long. — 

 Jour. Acad. Philad. vii. 111. — Rich woods, Ohio to Virginia and Alabama, and west to 

 the Mississippi. 



H. capitatum, Dougl. Only a span or so in height, tufted : copious fascicled roots 

 fleshy and almost as large as the short rootstocks : leaves longer than the stem, and with 

 blade mostly shorter than the petiole, ovate or roundish in general outline, 2 or 3 inches 

 long, softly hirsute or pubescent, pinnately 5-7-parted or at base divided ; the divisions 

 2-3-lobed or cleft ; the lobes oblong, obtuse and mucronate : flowers capitate-cymose : 

 calyx very hispid. — Benth. in Linn. Trans, xvii. 273 (excl. Calif, pi. &c.) ; A.DC. Prodr. 

 ix. 289; Hook. Kew Jour. Bot. iii. 202 (var. pumilum) ; Watson, Bot. King, 249. — Hillsides, 

 &c, Washington Terr, to the Sierra Nevada, California, and Utah. 



Var. alpinum, "Watson, 1. c. Nearly acaulescent in dense tufts : flowers distinctly 

 pedicellate in a somewhat open cyme close to the ground : calyx densely white-hairy, but 

 less hispid. — Eastern California and Nevada, in the higher Sierra Nevada and Humboldt 

 Mountains. 



-1— -s— Peduncle elongated, surpassing the petiole and often surpassing the subtending leaf : anthers 

 oblong-linear. 



■H* Cauline leaves elongated-oblong in general outline, pinnately parted or divided into 7 to 15 

 divisions. 



H. occidentale, Gray. Pubescent, hirsute, or sparingly hispid, a foot or two high: 

 divisions of the leaves oblong, an inch or two long, mostly incised or few-cleft, obtuse : 

 peduncles rather slender: cymes mostly dense or capitate: calyx deeply parted, its divi- 

 sions lanceolate and rather obtuse, more erect: corolla violet-purple, varying to white, a 

 third inch long. — Proc. Am. Acad. x. 314, & Bot. Calif. 1. c. H. capitatum, Torr. Pacif. R. 

 Eep. iv. 125, not Dougl. — Oregon (Nuttall) and N. & W. California. 



Var. Watsoni, Gray, 1. c. Commonly low, sometimes almost stemless, soft-pubes- 

 cent, especially the lower side of the leaves (which is sometimes canescent), as also the 

 sparsely hispid calyx : cyme sometimes open. — H. macrophyllum, var. occidentale, Watson, 

 Bot. King, 248, mainly. — Sierra Nevada, California, to Utah, Anderson, Bolander, Watson, &c. 

 Var. Fendleri, Gray, 1. c. Pubescence mainly hirsute or hispid, not at all canescent 

 or cinereous : divisions of the leaves inclined to ovate-lanceolate, acute or acuminate, in- 

 cisely serrate : peduncle shorter: cyme rather open: corolla white or nearly so. — Shady 

 ravines, Santa Fe", New Mexico, to Colorado, Fendler, Greene, T. M. Coulter, &e. 

 ■H- ++ Cauline leaves ovate in general outline, 3-5-parted or divided. 



1^. Virginicum, L. Stem (a foot or two high) and bright green leaves almost glabrous, 

 or with some scattered hairs : divisions of the leaves (2 to 4 inches long) ovate-lanceolate 

 or rhomboid-ovate, acuminate or acute, coarsely incised-toothed ; the lowest commonly 

 2-cleft and the terminal one often 3-lobed : peduncle usually once or twice forked : cyme 



