Bacillariece, Striatellacea?, Tetracyclus. 747 



subtilibu;!, circitei' 18 in 10 a., frustulis solitariis v. 2-3-c()iijuiictis, 

 e facie connectivali visis paria pieruraque 2 dissepimentorum medio 

 interruptorum ostendentibus. 



llab. in aquis dulcibus, ad rupes humectas, in paludibus rau- 

 scosis e regione raontana usque in subalpinam per l':]uropam inediam 

 passira, iraprirais in regione tatrensi (Sciiumann), Helvetia (Brun), 

 Helgio (Dblogne), Gerniania (Kirchner, BleisCH), Moravia, Sty- 

 ria (Nave, Grunow), alpibus austriacis (Grunow) et tirolensibus 

 (Heufler), inontibus pyrenseis et prope «Vercelli» Italiae (Grunow). 



— ValvJB habitu Odontidii mesodoniis. 



II. Fyutetracijclus (Ralfs) 



2. Tetracyclus lacustris Ralfs in Ann. a. Mag. Nat. Hist. vol. XII, 3009 

 t. 4, f. 2, Kuetz. P.acill. p. 127, t. 29, f. 70, W. Sm. Br. Diat. II, 



p. 38, t. 39, f. 308, Rabenh. Siissw. Diat. p. 63, t. 9, f. 1, Fl. 

 Eiir. .Algar. I, p. 302, Grun. in Wien. Verliandl. 1862, p. 412, 

 Pritch. Inf. p. 806, t. 11, f. 24-25, 0' Meara Ir. Diat. p. 318, 

 t. 29, f. 4, Sur. Alg. Jap. p. 16, t. 2, f. 27, Brun Diat. AIp. p. 131, 

 t. 8, t. 27, Striatella Thienemanni Ehr. Verbr. p. 136, Biblarium 

 Steila Ehr. in Ber. 1845, p. 75. Mikrogeol. t. 33, II, f. 11-12, Xll, 

 f. 10, Abh. 1870, t. 3, I, t 2o-28, Biblarium Gians Ehr. in Ber. 

 1845, p. 74, Mikrogeol. t. 16, III, f. 4 a-c, t. 17, f. 23 a, t. 16,11, 

 f. 46, t. 17, I, f. 20, t. 33, II, f. 8, XII, f. 3, Abh. 1870, t. 3, I, 

 f. 29, Biblarium Crux Ehr. Mikrogeol. t. 33, II, f. 3, Tetracycius? 

 Crax Ralfs in Pritch. Inf. p. 807, Biblarium v4rumosum Ehr. 

 Mikrogeol. t. 33, II, f. 13, Abh. 1870, t. 3, I, f. 24, Biblariwn 

 speciosum Ehr. ia Ber. 1845, p. 75, Mikrogeol. t. 33, Xll, f. 9. 



— Robustus, valvis elliptico-laiiceolatis, 35-65 a. longis, ventricosis, 

 ventre rotundato, costis transversis 4-12, versus centrura incurvis, 

 facie coiiuectivali costis brevibus alternis donata. 



llab. iu aquis dulcibus in Anglia, Helvetia, Islandia, Lapponia, 

 Japonia; fossilis in Finlandia, Oregonia, Sibiria (Ehrenberg). 



3. Tetracyclus emarginatus (Ehr.) W. Sm. Brit. Diat. II, p. 38, Grun. mo 

 in Wien. Verhandl. 1862, p. 412, Rabenh. Fl. Eur. Algar. I, p. 303, 

 Bibiarium emarginatum Ehr. in Ber. 1845, p. 74, Mikrogeol. 



t. 33, II, f. 6, XVI, f. 3-5, VII, f. 5-5*. — Valvis ad 30 a. longis, 

 apices rotundatos subapiculatos versus constrictis, inflatione einar- 

 ginata vel profunde incisa, striis ^Vg in 10 u.. 



Hub. in aqua dulci Aiigli:e (Greville, Gregory, W. Smith); 



48 



