Myriophyllum. 79 



ff Folia anguste oblonga usque ad obovata 

 rb 9 mm longa et 4 mm lata, calycis lobi 

 triangulari-lanceolati dz \,0 mm longi, flores 

 summi 4 — \ hermaphroditi. 



8 Folia obovata vel late oblonga 8. M. amphibium var. latifolium. 

 Folia anguste oblonga . . . 8. M. amphibium var. angustatum. 

 ß. Folia inferiora certe verticillata, nunquam opposita. 

 I. Folia omnia verticillata, flores semper verticillati, 

 merocarpia diu cohaerentia non cylindracea nee 



laevia Subsect. y. Spondylophyllumlorv. et Gray 



i . Folia submersa pinnata lobis capillaceis , emer- 

 gentia robustiora rhachi non nisi paullo dilatata 

 (exceptis bracteis M. verticillati valde abbreviatis 

 sed tunc anguste triangularibus pectinatis), caulis 

 plerumque simplex Series \ . Isophylleae. 



* Flores media parte inflorescentiae hermaphro- 

 diti certe adsunt, vel reduetione infimi foemi- 

 nei, raro summi masculi, bracteolae nunquam 

 filiformes. 



f Folia 3 na raro nonnunquam 2 na verticillata, 

 submersa pinnata , bracteolae anguste 

 trianguläres, fruetus subglobosus minute 

 4-sulcatus merocarpiis minute sparseque 



tuberculato-rugulosis. Asien 9. M. ussuriense. 



ff Folia 4 — 8 n& verticillata, submersa adsunt. 

 (3 Bracteolae palmiscissae , fruetus sub- 

 globosus minute 4-sulcatus laevis. 

 A Fruetus minute pedicellatus, mero- 

 carpia dorso minutissime lineato- 



angulata; Neu-Seeland 10. M. robustum. 



AA Fruetus sessilis, merocarpia dorso 



bene rotundata H . M. verticillatum. 



OO Bracteolae florum (j* vel £$ ex ovato 

 breviter acuminatae, merocarpia dorso 



et lateribus ruguloso-tuberculata . . (13. M. propinquum.) 

 ** Flores manifeste unisexuales, hermaphroditi 

 nunquam inventi, bracteolae florum q* fili- 

 formes tenuissime bifidae vel trifidae 3 mm 



longae ■ . . . \%. M. brasiliense. 



2. Folia submersa pinnata lobis capillaceis, emer- 

 gentia rhachi in laminam manifestam pinnati- 

 seetam vel integram complanata vel summa 

 linearia integerrima tenuia vel crassiuscula semi- 

 teretia, raro in M. propinquo sicut amphibia 

 pinnatipartita Series 2. Anisophylleae. 



* Folia floralia superiora ab amphibiis paullo 

 diversa pinnatipartita vel lobis diminutis in- 

 tegra vel integerrima linearia. 



f Folia floralia pinnatipartita vel integerrima 



tunc crassula apice submucronata 1 3. M. propinquum var. genuinum. 

 ff Folia floralia integerrima tenuia lineari- 



oblonga apice obtusa . . . 13. M. propinquum var. tenuifolium. 

 ** Folia floralia amphibiis valde heteromorpha 

 multo latiora vel multo breviora tunc oblonga 



