40 Fr. Buchenau. — Alismataceae. 



2. Pedunculi fertiles, (certe post anthesin) incrassati. 



* Pedunculi fertiles erecti. Lamina magna, lanceo- 



lata, basi mutica vel 1- usque 2-lobata (hastata 



nee sagittiformia) sub-pseudopenninervia. Flores 



magni. Filamenta elongato-fusiformia, glabra. 



Planta valida 2 6. S. macrophylla. 



** Pedunculi fertiles post anthesin recurvati. 



f Filamenta dilatata, pubescentia. Folia pseudo- 



penninervia 27. S. platypliylla. 



ff Filamenta glabra. 



Q Filamenta e basi ovata linearia. Fructiculi 

 oblongo-cuneati. Folia phyllodina late-li- 

 nearia; lamina anguste lanceolata . . . 28. S. Sanfordii. 

 QQ Filamenta conspicue dilatata. 

 /\ Stamina 7 vel 8. 



X Inflorescentia parva, racemosa, ver- 

 ticillis 1 usque 4 (raro 6). Planta 

 nunc folia phyllodina linearia tan- 

 tem, nunc etiam folia natantia for- 



mans 29. S. subulata. 



XX Gaules et folia elongata filiformia. 



Inflorescentia folia superans, panni- 



culata. Pedunculi graciles . . . 30. S. filiformis. 



/\/\ Stamina 12 usque 13. Folia linearia 



(nee filiformia). Inflorescentia folia sub- 



aequans, brevis, racemosa, verticillis 4 



usque G 3 1 . S. emersa. 



A. Calyeinae. Flores polygami. Spec. 1 — 3. 



1. S. spathulata (Smith) Buchenau. — Lophotocarpus spathulatus J. G. Smith in 

 Rep. Missouri Bot. Garden XI. (1899) 149, t. 57. — Annua; planta parva, ab aqua 

 fluminis regulariter rodundata. Caules 2 usque 5 cm longi, simplices, verticillum unicum 

 florum gerentes, a foliis superati, serius recurvati, teretes. Folia omnia phyllodina, ereeta, 

 linearia sive lineari- spathulata, rotundato-obtusa, (raro in laminam distinetam vel etiam 

 lineari-spathulatam obtusam desinentia), 3 usque 7 cm longa, 3 usque 6 mm lata. In- 

 florescentia simplex, e floribus 1 vel 2, raro 3 composita; bracteae minutae, ca. 3 mm 

 longae, membranaceae, late-ovatae, obtusae ; pedunculi ca. 1 usque 1 5 mm longi, gra- 

 ciles , fertiles post anthesin recurvati et incrassati (fruetus in limo maturescentes) ; 

 sepala persistentia, oblongo-orbicularia, obtusa, ca. 3 mm longa, indistinete nervosa, mar- 

 ginibus tenui-membranaeeis ; petala ovato-orbicularia, tenuissima, evanescentia, alba, ca. 

 mm longa; stamina 6 usque 9; filamenta linearia, sensim attenuata, 1,5 usque 2 mm 

 longa, glabra; antherae oblongae, ca. 1 mm longae; pistilla nunierosa. Fructiculi ca. 

 2 mm longi, griseo-flavescentes, oblique elongato-obovati, dorso et ventre anguste alati, 

 angulo interno graciliter rostrati, lateribus vix impressis; pericarpium tenue ; semen laeve. 



Massachussets, auf sandigen, den Gezeiten (aber nicht dem Salzwasser) ausge- 

 setzten Ufern des Merrimac-River. 



2. S. calycina Engelmann in Emory, Unit, states and Mexican Boundary survey 

 II. (1859) 212. — Lophiocarpus calycinus Micheli in DC. Monogr. Phaner. III. (1881) 

 61; Buchenau in Engler's Bot. Jahrb. II. (1882) 485. — Lophotocaipus calycinus 

 Smith in Rep. Missouri Bot. Garden VI. (1894) 34; Britton et Brown, 111. Fl. North. 

 Unit. States I. (1896) 87. — L. fluitans, californicus, calycinus, dvpiwprntius, • sponr 

 giosus Smith in Rep. Miss. Bot. Garden XI. (1899) 145 — 149, vide infra. — Maxim»' 

 variabilis. Annua, glabra. Caules molles, saepe debiles, 10 usque 40 (raro 50) cm 



