Potamogeton.'] 



NAIADES. 



4. HETEROSTYLUS. Nov. Gen, 



171 



Dioicus? Masc. — ? — FcEM. Spadix e'spatlia (foliorum basi) erumpens, exserta, 

 floribus nudis undique insertis sessilibus; superioribus arctis, subimbricatis stylo brevi; 

 iriferioribus sensim magis remotis stylo longiori; infimo radicali stylo filiformi longis- 

 simo ! Stigma simplex capitatum. Germen lanceolatum corapressum bialatum, dorso 

 carinatutn. Fructus: Achenium ohlongum compvessumj iitrinque subalatum; infimum 

 siiperne bidentatum. — Herba ajinna? aqiiatica^ maritima? vel salsuf/inosa, or<E occiden- 

 talis Americm horealis. Radix fibrosa Jibris simplicibus. Folia radicalia graminea mem- 

 hranacea^ tenera, striata^ linearia^ 6-S-uncias longa^ basi vaginantia, spathacea. 



1. H, gramineus, (Tab. CLXXXV.) 



r — 



r 



Hab. Wet plains of the Columbia. Dr Scolder. — This is an extremely curious plant, and certainly the 

 tj'pe of a new genus, to which I have assigned the present name, from the remarkable circumstance of the 

 female flowers or pistils (for they are perfectly destitute of any kind of floral covering), of the extremity of the 

 spadix, having a short style, those about the middle a longer one, and those at the base, especially among 

 the roots, where the spatha and the spadix have their origin, with a style two inches and more long, slender 

 and filiformi It is to be regretted that very few specimens were preserved, and those having, as far as can 

 be seen, only female flowers. 



Tab. CLXXXV. Fig. 1, Spadix and spatha ; / 2, 3. 4, Female flowers; / 5, Fruit ; / 6. The same 

 laid open ; f. 7, Seed : — magnified. 



+ 



5. PHYLLOSPADIX. Nov. Gen, 



Dioicus? Masc? — Fcem. Spadix e spatha curvata (foliorum basi) inclusa, canaliculata, 

 hinc supra florifera, marginibus foliiferis, foliis seu squamis oblongis subimbricatis ; 

 floribus nudis, serie singula subimbricatis, sessilibus. Ovarium sessile, lato-ovatum, sub- 

 globosum. S^^'^wsbreviusculis, crassus. S%;na capitatum. Fructus — f — Herba ores occi- 

 dentalis America borealis, aquatica, radice nodosa fibris albidis^ veterum foliorum reliquiis^ 

 vestita, Caules breves vaginati. Folia linearia^ elongata^ graminea^ subcoriacea, siccitate 

 nigrescentia, nervosay obscure costata^ integerrima, , Spatha lata, co7ivoluta, curvata, spadi- 

 cem includens. 



I. F. Scoukri. (Tab. CLXXXVI.) 



Hab. Dundas Island in the Columbia River, N. W. America. Dr Scolder.— 'V\\\^ is a second new genus 

 of Naiades which has rewarded Dr Scouler's researches in the north-west shores of America. Its nearest 

 affinity is doubtless with Zostera, from which the separated male flowers, the single style and stigma, and the 

 curious leafy border to the spadix, will at once distinguish it. 



Tab. CLXXXVI. Fig, I, Spatha, including the spadix ; / 2, Side view of the spadix removed from 

 the spatha; /. 3, The same, front view, the margins spread open ; / 4, Spatha, from which the spadix has 

 been removed ; /. 5, Single pistil : — more or less jnagnijied. 



6. POTAMOGETON. Z. 



1. R 7iatans. L.—Ph. Am, I. p. 120. E. Bat t. 1832.-/3, foliis minoribus anguslis 

 acutis. 



Hab. Sta'^nant waters, Canada, to Hudson's Bay.— ^. N. W. America. Mr Menzies. 



7/-*/^^ 



^'/^ 



j(C **■ 



I 



(5^-».r^ 



/^^fr 



