KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 26. N:0 2. 16-5 



Var. hercynka A. S. (1875). — V. rostrate. L. 0,029; B. 0, 01 mm. Strise. about 13 in 0, 01 mm. — 

 G. herc. A. S. Atl. IX f. .30, 31. C. abi/^sinica Grun. in Martelli Florida bogosensi.s p. 1.51 Pl. I f. 3 (1886). 

 Fresh water: Juliusliall, Harzbnrg (Atl.), Kingsjön (Sweden)! Abyssinia (Gnin.). 



22. C. lata Grun. Ms. — V. slightly asymmetrical, broadly lanueolate, with subrostrate to 

 rostrate ends. L. 0,042 to O.oöe; B. 0,oi6 to 0,oi8 mm. Median line almost straight and central. 

 Axial area narrow, linear, sligiitly dilated aroiind the central uodule. Stri» 9 (middle) to 12 (ends) 

 in 0,0 1 mm. slightly radiate in the middle, almost parallel at the ends, hnely puuctate. — Pl. IV f. 27. 



Fresh or slightly brackish water: Sweden (Gidf of Bothnia at Piteå; Öre sjö, near Borås)! 

 Ladoga! Domblitten, Rostock and Luneburg, fossil! 



This species resembles in outline C. Ehrcnheryii, bnt is much smaller and has less distinctly 

 pnnctate strite. 



23. C. Cuciiinis A. S. (187.5). — V. broad, with convex dorsal and almost straight or slightly 

 convex ventral margin. Ends rostrate-truneate. L. 0, 07 to 0,o',); B. 0,0->4 mm. Median line almost 

 central, slightly arcuate. Axial area narrow, slightly dilated aronnd the central nodule. Stripe 



8 to 9 (dorsal) to 10 (ventral) in 0, 01 mm. punctate; puncta 12 in 0, 01 mm., more distant on the 

 median ventral stria?. — A. S. Atl. IX f. 21, 22. 



Fresh water: Bengal (Atl.), Cameroon! 



24. C. Ehrenbergii Kutz. (1844). - V. asymmetrical, elliptic-lanceolate, with slightly 

 rostrate, obtuse ends. L. O.osi to 0,14; B. 0, 028 to 0,038 mm. Median line slightly excentric, 

 straight. Axial area narrow, but distinct, slightly dilated around the central nodnle. Striffi 7 to 



9 in 0,01 mm. slightly radiate throughont, ooarsely punctate; puncta 13 to 16 in 0, 01 mm. — 

 Navic. incequalis Ehb. Inf. Pl. XIII f. 18 (1838). Cymh. Ehrenh. Kutz. Bac. p. 79 Pl. VI f. 11. 

 W. Sm. b. D. i Pl. Il f. 21. A. S. Atl. IX f. 6 to 9; LXXI f. 74. V. H. Syn. p. 61 Pl. II f. 1. 



Fresh water: Iceland! Sweden (from Lapland to Skåne)! Norway! Finland! England! Bel- 

 gium (V. H.), Paris! Germanyl Switzerland! North America (Crane Pond, Löst Spring Ranch, 

 Washington territory. St. Rosa Cal.)! 



Var. dehcfa A. S. (1875). — V. assymmetrical-lanceolate, with slightly rostrate ends. L. 0,o6 3 

 to 0,08 3; B. 0,0 19 to 0,024 mm. Axial area narrow, not, or slightly, dilated around the centi^al 

 nodule. Striaj 8 to 9 (middle) to 11 (ends) in 0, 01 mm. — Cymh. delecta A. S. Atl. IX f. 17. 

 C. Ehrenheryii var. Atl. LXXI f. 80. V. Ehrenh. var. minor V. H. Syn. II f. 2. 



Fresh water: Greenland! Königsaue (Atl.), Puerto Monte, Chili (Atl.), Victoria, Splitters 

 Creek (Austr.)! 



25. C. lapponica Grun. (1879). — V. almost symmetrical, sublanceolate, gradually tapering 

 from the middle to the acute ends. L. 0, 033 to 0,037; B. 0,oo8 to 0,oo85 mm. Median line almost 

 central, straight. Axial area narrow; central area rather large, rounded. Median striie 16 in 

 0,01 mm., terminal strire about 21 in 0,oi mm., finely punctate. — Grun. in Cl. M. D. N:o 271. 

 Pl. IV f. 28. 



Fresh water: North Iceland! Repats in Gellivare, Luleå Lapmark, fossil, Sweden! 



This species has never been described or figured, but 1 suppose that Grunow denotes this 

 form, which occurs sparingly in Cl. M. D. N:o 271. This species seems to connect C. Ccsatii with 

 C stauroneiformis . 



2IÖ. 0. stauroiieifovinis Lägst. (1873). - V. lanceolate, almost symmetrical, with nearly 

 obtuse, attenuated ends. L. O, oss to 0, 04; B. 0, 009 to 0,oii mm. Median line almost central, 

 straight. Axial area very narrow; central area large, quadrate, somewhat broader outwards, not 

 reaching to the margins. Strise 16 to 17 in 0, 01 mm., slightly radiate, finely punctate. — Lägst. 

 Spitsb. D. p. 45 Pl. I f. 15. A. S. Atl. LXXI f. 62, 63. 



Fresh water: Beeren Eiland (Lägst.), Spitsbergen! 



