KONGL. SV. VET. AKADEMIENS HANDLINGAR. RAND 26. N:() 2. 187 



Var. maxima Cl. — V. more lanceolate. L. 0,0 8; B. 0,oi7 mm. Strite 12 in 0,(ii mm. 

 coarsely punctate; puncta 15 in 0,oi mm. — Pl. V f. 13. 



Fresh water: Pitt River, Oregon (Grove CoU.)! 



Var. tasmanica Cl. — V. nearly lanceolate. L. 0,o7; B. 0,oi5 mm. Strite aboixt 9 inO.ni 

 mm., coarsely punctate; the median, on one side of tlie valve, alternatelty longer and shorter. 



Fresh water: Campbell Town, Tasmania, fossil! 



Var. ornata GtRUN. (1880). — Lanceolate, gradually tapering from tlie middle to the obtuse 

 apex and basis. L. 0,06 to 0,i mm. B. O,oii to 0,oi3 mm. Axial and central areas combined in 

 a narrow, lanceolate space. On one side of the central nodule is a row of 3 to 5 stigmas, on the 

 other none, or one to two, stigmas. Stripe 10 in 0,oi mm. coarsely punctate; puncta 18 in 0,oi 

 mm. — (tRUN. in V. H. Syn. Pl. XXV f. 15. G. duhra.vicense Pant. III Pl. XX f. 294, 29(i (1893)? 



Fresh water: Guatemala, foss.! 



The typical forms of G. ventrico^tum belong to northern countries and for that reason it 

 is doubtful whether the varieties should not be considered as distinct species, although the difFe- 

 rences are only trifling. 



19. Gr. oxycephalum Cl. N. Sp. — V. large, gradually tapering from the middle to the 

 acute apex. Basis obtixse to truncate. L. O, o a to O, is; B. 0,oi8 to 0,o2 6 mm. Axial and central 

 areas uniting in a lanceolate space, with one (or two) stigma on one side of the central nodule. 

 Strice 8 in 0,ui mm., slightly radiate at the ends, distinctly punctate; puncta 21 in (),ö i mm. — 

 Pl. V f. 10. 



Fresh water: Demerara River! 



20. G. Salinaruni Pant. (1889). — V. linear, more or less gibbous in the middle, with 

 almost equally broad, roixnded obtuse apex and basis. L. 0,038 to 0,05i; B. 0, 0075 to 0,oo8 mm. 

 Terminal fissures of the median line distant from the ends. Axial area naiTow linear, suddenly 

 dilated around the central nodule to an orbicular space. Striaj 10 to 12 in O.oi mm., obscurely 

 punctate, slightlj'' radiate in the middle and at the ends. — G. oUvaceum var. salinarum Pant. II 

 p. 56 Pl. IX f. 160; XI f. 199; XVIII f. 287. G. oUvaceum var. fossilis Pant. II p. 56 Pl. XII 

 f. 204. G. salsa Pant. II p. 56 Pl. XVII f. 285. G. Salin. Icon. n. Pl. V f. 11, 12. 



Brackish water: Baltic at Riigen! Hungary fossil (Gyöngyös Påta! etc). 



Var. staurophora Pant. (1889). — Central area a transverse fascia. — G. oliv. var. staur. 

 Pant. n p. 56 Pl. XII f. 206. 



Brackish water: Hungary fossil (Pant.). 



G. Salinarum seems me to be perfectly distinct from G. oUvaceum by the distant terminal 

 fissures, the broader axial area, the central orbicular area and the more distant strire. The outline 

 of the valve is, as in most species of Gomphonema, variable. Between G. salsa Pant. and G. oliv. 

 var. fossilis Pant. I am unable to find any difference from the descriptions and the figures. 



21. G. transsylvanicnm Pant. (1893). — V. lanceolate, scarcely clavate, tapering from the 

 middle towards the obtuse ends. L. 0,oa4; B. 0,oi68 mm. Axial area narrow; central area large, 

 irregular. StriiB about 10 in 0, 01 mm., radiate in the middle, where they are of uneqiial length, 

 parallel towards the ends, not distinctly punctate. — Pant. Ill Pl. XIV, 219, 220. 



Fresh water?: Köpecz (Pant.). 

 Unknown to the aiithor. 



22. G. olivaceum Lyngb. (1819). — V. clavate, rarely sublanceolate, with broad, rounded, 

 obtuse apex and narrower basis. L. 0,0 1.^ to 0,025; B. 0,oo5 to 0,oo7 mm. Axial area indistinct; 

 central area rectangular. Strise 13 to 14 in 0, 01 mm., curved or radiate in the middle of the 

 valve, elsewhere almost transverse, not distinctly punctate. — Echinella oliv. Lyngb. Tent. Hydr. 

 D. p. 209 Pl. LXX f. c 1 to 3. G. oliv. Kutz. Alg. Dec. N:o 13 (fide Lägst.). W. Sm. B. D. 



