1206 Conjugatse, Desmidiacea?, Staurastrum. 



instructis ; e vertice visis triangularibus, lateribus concavis, an- 

 gulis late truncatis et in processus 2 sinu interposito rotuaclato, 

 productis; processu tertio introrsum sinus exsurgente, inter duos 

 alios porrecto. 



Hab. in lacu «Harvej» pr. «Wilkesbane» Americae (Ed. Potts). 

 — Diam. incl. acul. 30-38 a. 



** Semicellulas granulis obsit?e, granulis in processibus in lineas trans- 

 versas ordinatis. 



189. Staurastrum hexacerum (Ehrenb.) Wittr. Om Gotl. och Oelands 2017 

 Sotvattensalger p. 51, Slaurasb^um iricorne (Breb.) Menegh. 

 in Linnsea 1840, p. 225, Ralfs Brit. Desm. p. 134, t. 22, f. 11, f. 

 34, f. 8 [nec Ralfs in Ann. Nat. Hist. 1845, XV., p. 141, t. XI, 

 f. 2], Delp. Specim. Desm. Subalp. p. 145, t. XI, f. 48-50, Wolle 

 Desm. U. S. p. 128, t. 41, f. 36-38, Cooke Brit. Desm. p. 167, t. 

 58, f. 2, Slaurastrum, dilaiaium var. iricorne Rabenh. Fl. Eur. 

 Algar. III, p. 207, Binaiella iricornis Breb. Alg. Fal. p. 57, t. VIII, 

 Desmidium hexaceros Ehrenb. Abh. 1832, Inf. p. 141, t. X, f. 10, 

 excl. fig. f, Phycastrum tricorne Kuetz. Phyc. gerra. p. 137, Phyca- 

 sirum irilobaium Kuetz. Spec. p. 179, Phycasirum hexaceros 

 Kuetz. Species p. 180, Phycasirum [Amblyaciinium) Ralfsii Naeg. 

 Gatt. einzell. Alg. p. 125, t. 8, b ex parte. — Cellulis granulis pun- 

 ctiformibus asperulis ; semicellulis in quoque latere in processum 

 brevem, obtusura, plerumque integrum productis; e vertice visis 

 3-4-anguIaribus, angulis obtusis truncatisve, plus minus radiatim 

 productis; zygotis orbicularibus, spinis apice fissis ornatis. ^ 



llab. in fossis et stagnis in. Italia (Delponte), Gallia (Brebis- 

 son), Britannia (Ralfs, Cooke), Vogesis (Lemaire), Germania 

 (KuETZiNG, Rabenhorst), Helvetia (Naegeli), Hungaria (Istvanf- 

 Fi), Austria (Grunow), Suecia (Cleve, Wittrock, Lundell), Nor- 

 vegia (Nordstedt), Nova Semlia (Wille), Spetsbergia (Nordstedt), 

 Fennia (Elfving), Lulea Lapp. (Lagerheim), Beeren Eil. (Nord- 

 stedt), America boreali (Wolle, Wood), Nova Zelandia (Maskell), 

 Groenlandia (Boldt). — Var. semicirculare Wittr. Om Gotlands 

 ocli Oelands Sotvattensalger p. 52, t. 4, f. 9: duplo fere majus quam 

 forma typica; semicellulis a fronte visis subsemicircularibus, a ver- 

 tice visis triangularibus , lateribus leniter concavis. Long. cell. 

 39-41 p. jatit. 40-42 a., latit. isthm. 11 \j.. Gotl. ((Mellam nisby, 

 Snackgardel ». 



