1S(5<).] A'ji/ [Wood. 



tile cells scarcely swollen ; cell wall folded in at the ends ; chlorophyll 

 band single ; turns 6 ; spores oblong or elliptical, spore wall very thick. 



Diara. Art. steril. ,fl5"=.00146; spor. lat. 7i§^f"-7i|5"=.00133-.0016 

 long. 7ll5=0033. 



S. CRASSA. KtZ. 



Hab. In stagnis prope Philadelphia. 



s. DiLUTA. Sp. Nov. 



S. articulis sterilibus diametro subsequalibus ad duplo longioribus; 

 fructiferis hand turaidis ; fasciis spiralibus 5, angustissimis, laxis, valde 

 nodosis ; anfractibus pleiaxmque |, interdum 1 ; zygosporis sparsis, late 

 ellipticis vel ovatis aut globosis ; cytiodermate modice teuue, in utroque 

 fine nee protenso nee replicato. 



S. Sterile joints about as long as broad to twice longer, fertile cells not 

 swollen ; chlorophyll bands 5, exceedingly narrow, lax, strongly nodose ; 

 turns mostly ^, sometimes 1 ; zygospores few, broadly elliptical, ovate or 

 globose ; cell wall moderately thin, not infolded at the ends. 



Diam. Artie, steril. ^|3,"=.0()3". 



Hab. In stagnis prope Philadelphia. 



S. PARVISPORA. Sp. Nov. 



S. articulis sterilibus diametro 2-4 plo longioribus ; fructiferis hand 

 tiimidis, diametro 1-2^ plo longioribus ; fasciis spiralibus 4, angustis, 

 nodosis, anfractibus pluribus ; zygosporis parvissimis, ellipticis, diametro 

 1:^-2 plo longioribus; cytiodermate utroque fine nee protenso, nee 

 replicato. 



Sterile joints 2-4 times longer than broad ; fertile not tumid, l-2i 

 times longer than broad ; chlorophyll bands 4, narrow, nodose ; turns 

 many ; zygospores very small, elliptical, 1^-2 times longer than broad ; 

 cell wall not infolded at the end. 



Diam. Art. Steril ^|3_//=.oo3 spor. diam. transv. jlh"-^\h"=-^^-- 



00'',"^. • Inner 2 1 //_ 3 //_ 



UU^o , long 7500 7500 — f 



Hab. In stagnis, Hibernia, Florida. Mr. Wra. Canby. 

 GEN. ZYGNEMA. 



z. iNsiGNis. (Hassall), Ktz. 

 Hab. In stagnis prope Philadelphia. 



GEN. SIROGONIUM. 



S. RETROVERSUM. 8p. NoV. 



S. articulis sterilibus diametro 7-15 plo longioribus ; fasciis spiralibus 1, 

 rare 2, latis, granulatis ; anfractibus 1-9 ; articulis fertilibus valde tu- 

 hiidis, retroversis, copulatione genuflexa et sine tubo connexivo ; cytio- 

 dermate nonnihil crasso, utroque fine protenso vel replicato ; sporis 

 ellipticis. 



Sterile joints 7-15 times longer than broad ; chloroplyll band 1, rarely 

 2, broad, granulate ; turns 1-9 ; fertile article very tumid, retroverted ; 



