166 p. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



27. C. naviculitormis Auersw. (1?<61). — V. elliptic-lanceolate, slightly asymmetrical, with 

 rostrate-capitate ends. L. 0,o3 to 0,047; B. 0,01 to 0,oifi mm. Median line almost central, nearly 

 straight. Axial area narrow, linear, suddenly dilated in the middle to an orbicular space. Stria^ 

 in the dorsal side 14 (middle) to 1(S (ends) in (),oi mm., on the vejitral side 14 in <),oi mm. 

 — Auersw. Rabh. Alg. E. N:o 10(i5. V. H. Syn. PI. II f. o. C. cuspidata W. Sm. B. D. I PI. II 

 f. 22 a'. C. anglica Lagst. Spitsb. D. p. 42 PI. II f. 18 (1S78). A. S. Atl. IX f. (Wi V. H. Syn. 

 PI. II f. 5. 



Fresh water: (Greenland! Spitsbergen! Beeren Eiland (Lagst.), Norway (Romsdalen, Dovre)! 

 Sweden! Finland! Holstein! Harz (Atl.), Jenissey! New-Zealand! Australia! 



Heiberg (Consp. Crit. p. lUS) remarks that Cijnili. cnspidnta W. Sm. is not the species of 

 KuTZiNG, but possibly C. navicniiformis, of Avhich he gives several figures (PI. 1 f. 3), which 

 however are much more similar to C. amphicepliala than to this species. Laherstedt proposed the 

 name C aiifflnii, believing it to be identical with the species of W. Smith, which is too indistinctly 

 figured for identification. C. naiiculifurmis closely resembles C. a»i})/iitrj)hala, from which it is 

 distinguished by the larger central area. 



28. C. hybrida Urun. (1S78). — V. linear, almost symmetrical, with rostrate ends. L. 

 0,04.5; B. 0,009 mm. Median line almost central and straight. Axial area narrow; central area 

 large, subquadrate. StricV 11 in 0,oi mm. almost parallel, finely punctate. — Grun. in CI. M. D. 

 N:o 161. Icon, nostr. PI. IV f. 23. 



Fresh or very slightly brackish water: Sweden (Gothland, Lefrasjon in Skane)! 



29. (1. spuria Cl. N. Sp. — V. asymmetrical, lanceolate, with subrostrate ends. L. 0,o5 

 to 0,06; B. 0,01:5 mm. Median line very slightly arcuate, almost central. Axial area narrow, 

 gradually dilated towards the middle. Stria' 12 (dorsal, median) to lo (ventral and dorsal, termi- 

 nal) in 0,01 mm., slightly radiate in the middle, almost parallel in the ends, finely but distinctly 

 punctate. 



Fresh water: Talbot (Victoria, Australia)! Pichinicha (alpine region of Ecuador)! 



30. C. cuspidata Kiixz. (1844). — V. broadly linear-lanceolate, slightly asymmetrical, with 

 rostrate-capitate ends. L. 0,o4 to 0,o9.'>; B. 0,014 to 0,024 mm. Median line slightly excentric, 

 straight. Axial area narrow, linear; central area rather large, orbicular. Striic fir 10 (middle) 

 to 12 or 14 (ends) in 0,oi ram. radiate, finely liueate. Kiixz. Bac. PI. Ill f. 40. Heib. Consp. 

 p. 109 PI. I f. 4. A. S. Atl. IX f. 50 (typical) o3 to 55. V. H. Syn. p. (il PI. 11 f. 3. 



Fresh water: Sweden (Lappland to Upsala and Westergotland)! Norway (Finmark, Dovre)! 

 Finland! Paris! Belgium (V. H.), England! Germany! Italy! Greenland! Canada! Massachusetts! 

 Jenissey! Kamtschatka! Japan! New Zealand! 



Var. ohtusiuscula Grun. (in V. H. Types N:o 19). — L. O,ofi to O.ns; B. O.diri to 0,02 mm. 

 Ends more rounded. 



Fresh water: England (V. H. T.). 



31. ('. heteropleura Ehb. (1843). — V. slightly asymmetrical, lanceolate, with rostrate 

 and truncate to subrostrate, obtuse ends. L. 0,12 to 0, 1 .'> ; B. 0,o:i3 to O.04 mm. Median line 

 almost central, straight. Axial area distinct, linear. Central area large, slightly transversely 

 dilated. Striee 9 to 10 in 0,oi mm. slightly radiate throughout, puiictate; puncta 9 to 13 in 0,oi 

 mm. — Finnuldria hefcroplcuru Ehb. Am. p. 133. M. (t. V: 2 f. 11. Cymb. Iict. Kiixz. Bac. p. 79. 

 A. S. Atl. IX f. 4, 5. 



Fresh water (arctic and northern regions): Greenland! Norway (Dovre)! Sweden (Lappland)! 

 Russian Lappland! 



