Conjugatas, Desmidiacoae, Staurastrum. 1213 



dio verrucis similibus ornatis; latitudine (cum rad,) circiter duas 

 partes diametri longitudinalis corporis, crassitudine inilationis ba- 

 salis tertiam diametri transversalis corporis (rad. incl.) a^quante. 

 Hab. in stagnis in Hibernia (Barker, Cooke), Norvogia (Nord- 

 stedt), America boreali (Wolle). — Dimens. c. rad. Gl-77 « 43-48 

 crassit. 15 a; lat. isthni. 9 [).. (Nordstedt). Dimens. GO-75 <* 43-45 

 (Wolle). 



203. Staurastrum pusillum Wolle Desm. U. S. p. 130, t. 42, f. 47-50.- 2031 

 Minutissimum, oblongum, lineari-rectum, constrictione indistincta; 

 angulis in processus corniformes divergentes productis ; e vertice 

 visum quandrangulare, angulis in 4 processus divergentes apice ob- 

 tusos productis ; membrana granulata. 



llab. in stagnis New Jersey et Pennsylvania Americae borea- 

 lis (Wolle). — Dimens. 14 « 8 (sine processubus), Formae majores^ 

 ex Wolle, usque ad 25 [j. diam. praebent. 



204. Staurastrum Cerastes Lund. Desm. Suec p. G9, t. 4, f. 6, Wolie 2932 

 Desm. U. S. p. 133, t. 43, f. 3, Cooke Brit. Desm. p. 173, t. 



59, f. 3. — Submagnum, paullo latius quam longius; semicellulis 

 (introrsum) lunatis, sed in media parte introrsum subconico-ven- 

 tricosis, utrinqne in cornu robustum, non longissimum, incurvum, 

 apice subobtusum versus attenuatum, margine exteriore (convexo) 

 verrucis numerosis, emarginato- bifidis, sed apicem cornus versus 

 integris et papilliformibus dense obsitum, margine interiore (con- 

 cavo) nudum angustato-productis, ad basin utrinque papilla in- 

 structis; a vertice visis tri-quadri-angularibus, angulis in cornu 

 validum, strictum, e basi lata apicem tridentatum versus valdc at- 

 tenuatum productis, margine et intra marginem verrucis emargi- 

 nato-bifidis, apicera cornuum versus integris, papilliformibus den- 

 sissime ornatis. 



//a^, ad ({Bergsbrunna» in Uplandia, ad uBoIltorp)) in Ostro- 

 gothia, ad aUnnaryd et Femsjo)) in Smolandia Sueciae (Lundell) ; 

 in Hibernia et Anglia (Archer, Cooke), Fennia (Elfving), Norve- 

 gia(NoRDSTEDT, Wille), America boreali (Wolle). — Longit. 52-55 

 [j.., latit. c. corn. G3-72 u.., lat. isthmi 10-12 [j.. 



205. Staurastrum franconicum Reinsch Algenfl. von Franken p. 158, 2933 

 t. 12, f. 3 (sub Didyinidio), Staurastrum divar^icatum WoIIe Desra. 



U. S. p. 131, t. 40, f. 22. — Cellulis a fronte visis niedio utrin- 

 que plus minus emarginatis; seraicellulis (a fronte) ambitu tra- 

 pezicis usque rectangularibus, angulis plus minusve productis usque 

 cornutis, sursum versis ; e vertice visis ellipticis, 3-5-goniis, mar- 



