AMMIACEAE. 



273 



1. Hydrocotyle verticillata 

 Thunb. WHORLED MARSH-PENNY- 

 WORT. (Fig. 293.) Inflores- 

 cence proliferous, '-2' long; ver- 

 ticils 2-6-flowered ; pedicels usu- 

 ally less than \" long; fruit about 

 1" long, li"-2" broad, rounded 

 or truncate at each end; inter- 

 mediate ribs not corky-thickened, 

 the dorsal one acute. 



Frequent in fresh-water marshes, 

 and occasional near shaded borders 

 of salt water lagoons. Native. East- 

 ern I'nited States and West Indies. 

 Flowers from spring to fall. 



Hydrocotyle umbellata L., 



which differs in having a single 

 umbel with slender pedicels 2"- 

 6" long, is recorded as Bermudian 

 by Rein, Beade, Lefroy. H. B. 

 Small and Hemsley, but careful 

 search of the marshes has failed 

 to reveal its existence in Bermuda ; 

 its leaves are scarcely distinguish- 

 able from those of H. verticillata, 

 for which it may have been mis- 

 taken. 



2. CENTELLA L. 



Perennial herbs (some African species shrubby), ours with prostrate stems 

 rooting and sending up tufts of long-petioled leaves at the nodes, together with 

 1-3 long-rayed umbellets of small white flowers, the true umbel sessile. Petiole- 

 bases sheathing. Bracts of the involucels 2-4, mostly prominent. Calyx-teeth 

 none. Disk flat, or slightly concave. Styles filiform. Fruit somewhat flat- 

 tened laterally, rather prominently ribbed, the ribs mostly anastomosing; oil- 

 tubes none. [Latin, diminutive of 

 centrum, a prickle.] About 20 spe- 

 cies, most abundant in South Africa. 

 Type species : Centella villosa L. 



1. Centella asiatica (L.) Urban. 

 OVATE-LEAVED MARSH-PENNYWORT. 

 (Fig. 294.) Stem l'-G' long. Petioles 

 2-10' long, sometimes pubescent ; 

 blades ovate, rather thick, rounded at 

 the apex, broadly cordate at the base, 

 not peltate, V-2.' long, repand-dentate ; 

 pedicels much shorter than the leaves, 

 V 2' long; umbellets capitate, 2-4- 

 flowered, subtended by 2 ovate bracts ; 

 flowers nearly sessile ; fruit 2"-2" 

 broad, about li" high, prominently 

 ribbed and reticulated. [Hydrocotyle 

 asiatica L. ; H. repanda Pers. ; Cen- 

 tella repanda J. K. Small.] 



Common in marshes and locally on 

 hillsides. Native. Southeastern United 

 States, West Indies, Old World tropics. 

 Flowers from spring to autumn. 



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