(5) Eleocharis acicularisK. &S., spike TUsh. , 

 (3*) Scirpus validus Vahl., great bulrush. 

 (3*) " fluviatilis Gray, river bulrush. 

 (4, 5) " americanus Pers., triangular bulrush. 



(2) Dulichium arundinaceum Britton. 



(i*) Car ex lanuginosa Michx., woolly sedge. 



(5) " filiformis L., slender sedge. 



(5) " aurea Nutt., golden sedge. 

 (5*) " stricta Lam., narrow sedge. 

 } (S) " spp., sedges. 



(5) Rynchospora capillacea Torr., beak rush. ^''' 



(5) Cladium mariscoides Torr., twig rush. 



(3) Symplocarpus foetidus Nutt., skunk cabbage. 

 (3, 5) Peltandra virginica Knuth., arrow arum. 



(4) Acorus calamus L., sweet flag. 



(2*) Spirodela polyrhiza Schleid., duckweed, 

 (i*) Lemna trisulca L., duckweed. 

 (2*) " minor L., duckweed. 



(2) Wolffia Columbiana Karst., smallest duckweed. 

 (3*) Pontederia cor data L., pickerel- weed. 



(3) Heteranthera duhia MacM., water star-grass. 



(5) Juncus nodosus L., knotted rush. 



(s) " canadensis Gay., Canada rush. 

 (5) " halticus Willd., Baltic rush. 

 (3,5) Iris versicolor L., blue flag. 

 (3) Saururus cernuus L., lizard's tail, 

 (i, 3, 5) Polygonum amphibium L., water smartweed. 

 (i> 3> 5) " Muhlenbergii Wats., water smartweed. 



(3, 5) " hydro piperoides Michx., water pepper, 



(i*) Ceratophyllum demersum L., horn wort. 

 (2*) Nymphaea advena Ait., yellow pond lily. 

 (2*) Castalia tuberosa Greene, white water lily. 

 (2*) Brasenia Schreberi Gmel., water shield. 



(2) Nelumbo lutea Pers., American lotus or nelumbo. 

 (i) Ranunculus aquatilis L., white water buttercup. 



(i) " delphinifolius Torr., yellow water buttercup. 



(5) " pennsylvanicus L., bristly buttercup. 



(3) Callha palustris L., marsh marigold. 



(i, 3) Radicula Nasturtium-aquatica B. & R., water cress. 



(i) " aquatica Rob., lake cress. 



(3) " palustris Moench., marsh cress. 



(3) Cardamine hirsuta L., bitter cress. 

 (3, 5) Penthorum sedoides L,, ditch stonecrop. 



(3) Potentilla palustris Scop., marsh cinquefoil. 



(2) Callitriche palustris L., water starwort. 



(5) Hypericum virginicum L., marsh St. John's- wort. 



(3) " canadense L., Canada St. John's- wort. 

 (5) Lythrum alatum Pursh, winged loosestrife, 



(3, 5) Ludvigia palustris Ell., water purslane. 



17 



