45 MONOCOTYTEDONEÆ. ECHINODORUS. 
simplici, seepe prostrato; floribus umbellatis vel rarius verticillatis, 
longe pedicellatis, sepalis post anthesin erectis; staminibus 9; ear- 
pellis paucis, reniformibus, eum parietibus crassis, lateraliter eglan- 
dulis. Alisma tenellum Mart. in Róm. et Schult. Syst. 7, p. 1600; 
Kunth Enum. 3, p. 149; Seub. in Mart. Flor. bras. fasc. 8, p. 105, 
t. 13, fig. 2. Al. ranunculoïdes var. brasiliana A. de St-Hil. Voy. Dist. 
Diam. 2, p. 432. Echinodorus parvulus Engelm. in Gray Man. of 
Bot. 1865, p. 492. Ech. subulatus Eng. in Gray Bot. ed. 1, p. 460. 
Planta 12-30 cent. alta, omnino glabra, stolonifera. Rhizoma obli- 
quum lignosum, radices validas elongatas agens. Folia radicalia; 
petioli complanati, basi parum dilatati, breves, limbum æquantes vel 
superantes, 20-25 mill. longi ; limbi coriacei, lineari-lanceolati, lan- 
ceolati vel ovati, basi in petiolum decurrentes, apice acuti, 10-25 
mill. longi, 3-5 mill. lati, tri-nervii, nervis secundariis, obliquis, remo- | 
tis, venis paucis. Scapus simplex, folia sæpius valde superans, tenui- | 
ter striatus, plus minusve prostratus. Flores umbellati (6-10) vel 
rarius in verticillos 2-3 dispositi, pedicellis gracilibus 15-20 mill. 
| 
| 
longis, sub anthesin erecti postea irregulariter curvato-reflexi. Brat- 
teæ exteriores 3, pedicellis multo breviores, lanceolato-ovatze, acute | 
rarius obtusæ, 5 nerviæ, basi coalitee. Sepala late ovata, obtusa, 
margine scariosa, 1,5-2 mill. longa, post anthesin erecta, fructum 
amplectentia ; petala albida, obovata, sepala superantia. Stamina 9, 
bi-seriata, 6 sepalis, 3 petalis opposita, antheris elongatis filamenta 
æquantibus. Ovaria 12-15 capitata, stylo brevi apicali. Carpella vix 
compressa, ovata, plus minusve intus curvata, styli vestigio breviter 
rostrata, 5 costata (costis tribus dorsalibus, duobus lateralibus), parie- 
tibus crassis, crustaceis. Semina testa tenui, lævi, translucida. 
In America australi et in civitatibus meridionalibus Americæ borea- 
lis frequens, nisi petioli longitudine minime variabilis : in civit. 
Massachusset, Michigan, Illinois, Missouri, etc. (Echinodorus parvu- 
lus Engelm. Helianthium pusillum Engelm. in sched.); in Mexico, 
Llano de S. Martin (Karsten), Orizaba (Weber in herb. Vindob.), 
Vera-Cruz (F. Mueller n. 2142 in herb. Kew); in- Venezuela, Caracas 
(Gollmer, in herb. Berol. Grosourdy in herb. Mus. Paris.); in Peruvià 
(Spruee n. 4401); N. Granata (Purdie); Guyana ( Schomburgk 
n. 163); in Brasiliæ prov. Para (Spruce, cum forma minima A. ephe- 
merum in schedulis) ad Santarem (Riedel n. 1554, 836 in herb. - 
Petrop.), Piauhy (Gardner n. 2740), Bahia (Blanchet n. 2743), Minas 
Geraes (Claussen, Weddel n. 1324); Brasil. merid. (Sellow); Rio 
Janeiro, etc. (St-Hilaire in herb. Mus. Par.), ad Lagoa Santa (ubi in 
