452 riCKEKEL WEED FAMILY. 



CXX. PONTEDERIACEiE, PICKEREL WEED FA:\1ILY. 



A few water plants, witli jiorfeet and more or less irregular 

 flowers from a spathe, the perianth with 6 petal-like divisions 

 and free from the 3-celled ovary ; stamens 3 or 6, unequal or 

 dissimilar, inserted in the throat of the periantli; style 1, the 

 stigma 3- or G-lobed or toothed. 



« stamens 6; perianth funnel-Jovm. 



1. PONTEDERIA. Floweis in a terminal spike. Perianth of divisions in-C!,'iiIarly united 



below in a tube, the 3 most united forming an upper lip of 3 lobes, the others more 

 spreading and with more or less separate or lightly cohering claws forming the lower 

 lip, oi)en only for a day, rolling up from the apex downwards as it closes ; the 6-ribbed 

 base thickening, turning green, and inclosing the fruit. Stamens 6, the 3 lower in the 

 throat, with incurved filaments ; the 3 upper lower down and shorter, often imperfect. 

 Ovary 3-celled, 2 cells empty, one with a hanging ovule. Fruit a 1-celled 1-seeded 

 utricle. 



2. EICIIHORNIA. Differs in having the flowers spicate-racemo.se or paniculate, the 3 



cells of the ovary all developing and each many-ovuled, the upper stamens Included 

 and the lower ones e.xserted. Plant (in ours) floating free. 

 * » Stamens 3 ; perianth salverform. 



3. HETEE.\NTIIEEA. Flowers l-few from a spathe which bursts from the sheathing 



side or base of a petiole. Perianth tube slender, the limb nearly equally parted and 

 e[ihemeral. Capsule 1-celled or incomjiletely 3-celled, many-seeded. 



1. PONTEDERIA, riCKEREL WEED. {J. Pontedera, an early 

 Italian botani.st.) 



P. cord^ta, Linn. Com.mon P. Everj'where in shallow water ; stem 

 1^-2- high, naked below, above bearing a single, petioled, heart-shaped 

 and oblong or lance-arrow-.shaped, obtuse leaf, and a spike of purplish- 

 blue, small flowers ; upper lobe with a conspicuous yellowish-green spot ; 

 flowers all summer. 21 



2. EICHHORNIA. (,/. A. F. Eirhhnrn, a Gorman.) 



£. speciosa, Kunth. (E. cu.4ssipes, Poxtederi.x azurea). From S. 

 .A iiicr., now frequent in greenhouses, and in lily ponds in summer; leaf 

 blade nearly orbicular, shining green, the petiole terete and swollen mid- 

 way hilo a hollow bladder; flower large (IV long), violet, .several in a 

 raceme ; roots feather-like and purplish, free "in the water. 



3. HETERANTHERA, MUD PLANTAIN. (Greek: unlike anthers.) 



* tStaiiti'us )tii('(jnf/J. /./((> two poHterior with ovate yellow anthers, the other 

 loHijcr with an ohUnig or sagittate fjrcenish anther. 



H. renif6rmis, Ruiz. & Pav. In mud or shallow water. Conn., S. and 

 W.; with floating, round-kidney-shaped leaves on Jong petioles, and ."3-5 

 ephemeral white flowers, their perianth with a .slender tube, bearing 6 

 nearly cfjual divisions. 



H. limdsa, Vahl. In mud, Va., S. and W.; distinguished by its oblong 

 or lance-oblong leaves, and solitary, larger, blue flower. 



* » Stamens all alike, with sagittate anthers. 



H. (or Scuof.i.eua) graminea, Vahl. Water Star Grass. A grass- 

 like weed growing under water in streams, from N. Eng., W. and S., with 



