910 CoDjugatse, Desmidiacese, Pleurotaeniopsis. 



Sectio 2. Cosmaridium (Gay) — CosutaricUum Gay sectio 2. Eucosmaridium 

 Hansg. Prodr. p. 246: Cellul,» oblongae vel orbiculares, medio constrictione 

 profunda lineari instructse; istlimus pro ratione angustus. 



9. Pleurotaeniopsis Cucumis (Corda) Lagerh. Algol. Bidrag. II, p. 197, 2191 

 Cosmarium Cucumis Corda Alman. de Carlsb. 1835, p. 121, f. 27, 

 1839, p. 243, Menegh. in Linn. 1840. p. 220. Ralfs Brit. Desmid. 

 p. 93, t. XV, f. 2, Rabenh. Bacill. exs. sub n. 10, Alg. n. 304 

 et 1007, Fl. Eur. Algar. 111, p. 161, Lund. Desm. Suec. p. 52, Kir- 

 chn. Alg. Schles. p. 146, Wolle Desm. U. S. p. 58, t. 15, f. 6-9, 

 Cooke Brit. Desra. p. 84, t. 36, f. 11, Cosmarium Cucumis a 

 iypicum Klebs Preuss. Desm. p. 30, Cosmay^idium Cucumis Hansg. 

 Prodr. p. 190, n. 371 et p. 246, Euastrum rupesire Naeg. Einzell. 

 Alg. p. 119, t. VII A f. 6 sec. Reinsch, De-Not. Element. p. 41, 

 n. 23, t. III, f. 21, Euastrum integerrimum Ehrenb. Inf. p. 163, 

 n. 199, t. XII, f. 9? Cosm.arium Kuetz. int. Spec. p, 174? — Cellulis 

 mediocribus, 54-94 (-107) s 37-56,30-40 ^a. crassis, late cylindricis, 

 utroque polo late rotundatis, tertiara partem vel subduplo diame- 

 tro longioribus profunde constrictis, sinu lineari, isthmo 16-32 [i. 

 lato; seraicellulis diametro subsequalibus, angulis inferioribus ro- 

 tundatis, dorso alte convexis; membrana levissima vel subtiliter 

 punctata. 



Hab. in stagnis paludibusque in Italia (De-Notaris), Gallia 

 (Brebisson, Petit), Vogesis (Lemaire), Germania (Rabenhorst, 

 Klebs, Kirchner), Helvetia (Naegeli), Hungaria (Istvanffi), Bohe- 

 roia (CoRDA, Hansgirg), Polonia (Raciborski), Britannia (Archer), 

 CooKE, Ralfs), Austria (Grunow), Suecia (Cleve, Lundell), Nor- 

 vegia (Nordstedt), Dania (Jacobsen), Spitzbergia (Nordstedt), 

 Nova Semlia (Wille), Groenlandia (Nordstedt), America boreali 

 (Wolle) et Brasilia (Wille) — Cellulse e verticae visae ellipticse. 

 — Var. jielvetica Nordst. in Wittrock et Nordstedt Alg. aq. dulc. 

 exs. n. 378, in Botaniska Notiser 1880, p. 120 et in Hedwigia 1881, 

 p. 13; forma minor, semicellulis apicera versus rapidius attenua- 

 tis, in latere interiore merabranaj dense scrobiculatis In. Helvetia. — 

 Dimens. 48-56 « 26-36 [j.., crass. 22-26 <j.., lat. isthm. 10-12 p.., — 

 Cosm. subquadralo Nordst. (et C. variolato Lund.) valde affinis in 

 statu viventi accuratius examinanda est, quura cellulas tantum ex- - 

 siccatas vidit et adeo structura massa3 chlorophyllaceaa auctori in 

 conspectura non satis evidenter venit. — Forraa trigona N. : semi- 

 cellulis e vertice visis trigonis, lateribus rectis, angulis obtuso-ro- 



