CRYPTOGAMIA. 
631 
736. HYMENOPHYLLUM. Sorus marginalls, recepfa- 
culo cylindraceo insertus. Indusium bivalve, sorum 
includens* 
V. HYDROPTERIDES. 
737* ISOETES. Capsula raembranacea, non dehiscens, 
frondis basi immersa, 1-locularis. iSmiwa angulata, 
receptaculis pluribus filiformibus inserta. 
738. SALVINIA. Indusia irabricata, connata, capsiilam 
unilocularem mentientia. Semina receptaculo cen- 
tral! inserta. 
739 * AZOLLA. Capsula unilocularis, radicalis, globosa, 
. polysperma. 
I. GONOPTERIDES. 
713. EauiSETUM. Gen.pl.m4. 
1. E. caulibus sterilibus simpliciter ramosis, ramis scabriiis- 
culis tetragonis, fructificationibus simplicibus, vaginis 
cylindraceis inciso-dentatis, dentibus aciuis. Willd. 
enum. 1065. Willd. sp. pi. 5. p. 1 . 
Icon. Schkuhr Jilic. t. 167. 
In low and sandy fields : Pensylvania and Virginia. IJ , . 
April, May. v. v. 
2. E. caulibus sterilibus fructificantibusqueduplicato-ramo- 
sis, ramis scabriusculis deflexis tetragonis, ramulis 
subtriquetris. Willd. enum. 1005. Willd. sp. pi. 5. 
p. 3 . 
Icon. Schkuhr Jilic. t.\66. Fl.dan.\\S2. 
In low shady woods ; New York to Virginia. % . April 
— June. V. V, 
3. E. caulibus subramosis, ramis subquaternis tetragonis 
glabris, spica cylindracea terminali. — Willd. sp. pi. 5. 
p. 4. 
In swamps : New York to Virginia. 1/ . May. v. v. 
Resembles E. limosum. 
4 . E. caulibus simpliciter ramosis glabris sulcatis, ramis 
pentagonis apice spiciferis. Willd. enum, 1005. 
Willd. sp. pi. 5. p. 5. 
arvense. 
sylvaticum. 
uliginosum. 
palustre. 
