644 Bacillarieas, Trachyspheniaceae, Trachysphenia. 



fig. 28. — Frustulis ovatis, 11-25=; 9-10, in laminam cellulosam 

 coadunatis. 



Hab. in rivulis pr. Lundam in Scania Sueciae (C. Agardh), in 

 fonte ad «Terebize» in Galicia orientali (R. Gutwinski). — In M. 

 circularh frustulis rarius nidulans. 



Species removenda. 



0. Meridion marinum Greg. Diat. of the Cljde p. 25, t. 2, f. 41 si- 

 stit Opephoram marinayn Petit. 



Genus admodum dubium. 



ONCOSPHENIA Ehr. [1845] iu Ber. Berl. Akad. 1845, p. 72 (Etym. 

 oncos tumor et sphen cuneus), Kuetz. Sp. p. 11, Rabenh. Fl. Eur. 

 Algar. I, p. 296, De-Toni Osserv. Bacill. p. 904. — Frustula qua- 

 drangula, cuneata, non concatenata, nodulis destituta; valvulse aequa, 

 les apicibus ob formam cuneatam et uncinatam inaequalibus. 



1. Oncosphenia carpathica Ehr. loc. cit. p. 79, Pritch. Inf. p. 7G8, 2502 

 t. 8, f. 1. — Valvis cuneatis, vix 35 y.. longitudine sequantibus, 

 laxe striatis, costis 11, altero fine turgido rotundato recto, altero 

 attenuato uncinato. 



Hab. in aquis Carpathorum (Ehrenberg). — An, ut sestumat 

 cl. Ralts, frustula DiatomatiS elongati var. tenuis irregulariter 

 incurva sistit? 



Familia XII. Trachyspheniaceae P. Petit. 



Tracht/spheniaceoe P. Petit [1889] in Pell. Les Diat. II, pag. 87, De-Toni [1890] 

 Osserv. tasson. Bacill. p. 904. 



Valvse secus axin longitudinalem symmetricje, secus axin trans- 

 versalem asymmetricse, grosse punctatae, subinde costis transverse 

 elongatis donatse, cuneiformes, nodulo centrali nullo, terminalibus 

 plerumque absentibus; zona connectivalis rectangularis, raro cunei- 

 forrnis. 



Phseophora adhuc ignota. 



Conspectus Generum 



Trachysphenia Petit. — Valvte cuneiformes, punctis crassis et transverse 

 et longitudinaliter seriatis ornatae ; pseudorhaphe plus minus angusta. Fru- 

 stula e zona connectivali rectangularia. 



