184 P. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



3. A. gibbei*u1a G-kun. (1880). — Lanceolate, with obtuse ends. L. 0,oi8 to 0,02; B. 0,0045 

 to 0,005 mm. Upper V. with wide, lanceolate area. Strise 22 in 0, 01 mm. Lower V. with iiarrow, 

 lanceolate axial area, centrally not transversely dilated. Strite about 22 in 0,oi mm. radiate, 

 more distant in the middle tlian towards the ends. In the zonal view the upper margin of tlie 

 lower valve is gibbous in the middle. — A. D. p. 22. V. H. Syn. Pl. XXVII f. 47 to 49. 



Hot springs: East Indies (Grrun.). 



Var. angustior Grun. — Valves narrower. — V. H. T. N:o 139. 



Fresh water: Stuttgart. 



4. A. Holstii Cl. (1881). — Lanceolate, with obtuse, subrostrate ends. L. 0, 028; B. 0, 009 

 mm. Upper V. with broad and lanceolate axial area. Strise 14 in 0,oi mm. subradiate in the 

 middle, parallel at the ends. Lower V. with very narrow axial area, dilated in the middle to a 

 central area not reaching to the margin. StricS 13 (middle) to 14 or 15 (ends) in 0,oi mm., ra- 

 diate. — D. from Greenl. and Arg. p. 13 Pl. XVI f. 6, 7. 



Fresh water: Greenland, Kornak! 



5. A. marginulata Grun. (1880). — Elliptical. L. 0,oi! to 0,022; B. 0,oo5 to 0,oo8 mm. 

 Upper V. with broad, lanceolate area. Striee 24 in 0, 01 mm. marginal. Lower V. with very 

 narrow or indistinct axial area. Central area large, quadrate. Strite 23 to 27 in 0, 01 mm. — 



A. D. p. 21. V. H. Syn. Pl. XXVII f. 45, 46. Achnanfliidhim delicatulum Schum. Tatra p. 61 

 Pl. II f. 22? 



Fresh water, alpine regions: Arctic America! Greenland! Norway (Dovre)! Russian Lap- 

 land (Fiskarehalfön). 



6. A. americana Cl. (1893). — Broadly elliptical with obtuse or subtruncate ends. L. 0,01.3; 



B. 0,006 mm, Upper V. with broad, lanceolate area and about 16 striaj in 0, 01 mm., unilaterally 

 interrupted. Lower V. with lanceolate area. Strise about 17 in 0, 01 mm., radiate and shortened 

 in the middle of the valve. — Diatomiste II Pl. III f. 17, 18. 



Fresh water: Crane Pond, North America! 



7. C. biharensis Pant. (1889). — Elliptical. L. 0,023 to 0,026; B. 0,013 to 0,oig mm. 

 Upper V. with lanceolate area, transvei-sely dilated in the middle, and distinct median liue. StriaB 

 11 to 12,5 in 0,01 mm. radiate. Lower V. with marginal, costate and radiate strife, 8 to 12,5 in 

 0,01 mm. and with a row of parallel strife (12,5 in 0, 01 mm.) along the median line, separated 

 from the mai'ginal strise by narrow lateral areas. — Pant. II p. 57 Pl. V f. 90, 94. 



Marine: Bory, Hungary (Pant.). 



Var. minor Pant. (1889). — L. 0,oi6; B. 0,o8 mm. Upper V. with a row of short strite, 11 in 

 0,01 ram., at some distance from the margin, and enclosing a broad, lanceolate area without median 

 line. Lower V. with 11 strite in 0, 01 mm., reaching to the median line. — Pant. II Pl. IV f. 75, 76. 



Marine: Hungary, fossil (Pant.). 



8. €. pygmaea Schum. (1864). — Broadly elliptical, with rounded ends. L. 0,oo7 to 0,oii 

 mm. StritC 15 in 0, 01 mm. Upper V. with broad, lanceolate area. Lower V. with nari'ow area. 

 — Preuss. D. I Nachtr. p. 19 Pl. II f. 11. 



Brackish water: Baltic (Schum.). 



9. C. Pelta A. S. (1874). — Broadly elliptical. L. 0,02; B. 0,oi5 mm. Upper V. with 

 broad, lanceolate area. Striic 12 in (),oi mm. mai'ginal. Lower V. with straight median line. — 

 N. S. D. p. 93 Pl. III f. 17. Atl. CXCI, 6 to 9. 



Marine: North Sea (A. S.). 



10. C. qiiarnereiisis Grun. (1862). — Elliptical. L. 0,022 to 0,035; B. 0,012 to 0,oi6 mm. 

 Up])Pi' V. with very large, nsually irregularly pniuttate area. Striai 9 in 0,oi mm., marginal, not 



