Conjugat», Desmidiaceoe, Staurastrum. I'i03 



c. ic, Fl. Eur. Algar. III, p. 205, Wolle Desra. U. S. p. 124, t. 40, 

 f. 37-39, t. 52, f. 29-31, Cooko Urit. Desm. p. 107, t. 58, f. 1, 

 De-Not. Eleraent. p. 54, n. 49, t. V, f. 50, Phycastrum Ralfsii 

 Kuetz. Spec. Alg. p. 181?, Goniocysiis {Staurastrum'l) bifida 

 Hassall Freshw. Alg. p. 355, t. LXXXV, f. 2, excl. synon. — Leve ; 

 semicellulis 3-4-5-radiatis, a vertice 4-5-angularibus, 3-4-radiatis, 

 radiis omnibus valde elongatis, achrois, levibus, in apice bi-(rarius 

 tri-) fidis, laciniis divaricatis; zygotis quadratis, spinis paucis su- 

 bulatis instructis. 



Hab. in stagnis inter A Igas varias in Anglia et Scotia (Ralfs, 

 Hassall, Cooke), Gailia (Brebisson, Petit), Helvetia (Naegeli), 

 Italia (De-Notaris), Vogesis (Lemaire), Belgio (De-Wildeman), 

 Iluugaria (Markus) , Germania (Rabenhorst), Suecia (Cleve, 

 Lundell), Norvegia (Nordstedt, Wille), Fennia (Elfving), Da- 

 nia (Jacobsen), Araerica boreali (Wolle), Japonia (Roy, Bisset). — 

 Sec. Rabenhorst 1. c. Staurastro paradoxo simillimum et vix di- 

 scernendura nisi membrana constanter levi, radiorura apice plerura- 

 que bifido. 



179. Staurastrum bibrachiatum Reinsch Contrib. Alg. Fung. p. 85, 2907 

 t. IG, f. 2, nec Wolle. — Semicellulis a fronte arabitu trapezicis, 

 sinu rotundato disjunctis, angulis cornubus gracillimis, exasperatis, 

 binis, divergentibus instructis; cornuura longitudine semicelluIaG lati- 

 tudine maxima majore. 



Hab. in Franconia Germanise (ut videtur). — Dimens. corn. 

 inclus. 27,8-33,3 s 27,8-33,3. — A Staurasiro paradoxo, Arachne, 

 ictracero differt angulis bicornutis. Adest quoque homoniraa species 

 quai sequitur cujusque nomen mutavi. 



180. Staurastrum subbibrachiatum WoIIe in BuU. Torrey Bot. Club 2908 

 1876, et Hedwigia 1877, p. 187 nec Reinsch. — Semicellulis subqua- 

 drangularibus vel cuneatis,gradatira sursura arapliatis,apicibus trun- 

 catis, apicibus lateralibus in processum singulura, elongatum, diver- 

 gentem, hyalinura productis, margine rugosis vel denticulatis; pro- 

 cessibus corpore 2-3-pIo longioribus ; e vertice visis ellipticis, iu 

 quoque apice processu singulo instructis, apicibus obtusis dentatis. 



Hab. in stagnis ad «Bethlehem» in Pennsylvania Americae bo- 

 realis. — Diraens. cum proc. 45-55 ^ 36-80. Ab ipso Wolle in ope- 

 ribus serioribus omissum. 



181. Staurastrum piatycerum Josh. Burmese Desmid. in Journ. Linn. 2909 

 Soc. 1886, vol. XXI, p. 643, t. XXIV, f. 1, 2. — Cellulis a fronte 

 conspectis ovatis, brachiis corporis ipsius triplo longioribus quam 



