90 p. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. - 



Var. transversa A. S. (1876). — V. very slender. L. 0, 17 to 0,22; B. 0,02 mm. Median line 

 very broad and oblique. Striae 9 in 0,01 mm. — Nav. transversa A. S. Atl. XLTII f. 5 to (>. 

 Fresh water: Finland (Sodankyla)! America (Monticello)! Anstralia (South Yarra)! 



58. P. Esox Ehb. (1843). — V. triundulate, with obtuse ends. L. 0,o8 to 0,i4r); B. 0,012 

 to 0,022 mm. Median line not complex, narrow. Terminal fissures comma-like. Area linear, 

 narrow, less than ^'3 of the breadth of the valve. Strise 8 to 10 in 0,o 1 mm., divergent in the 

 middle, convergent at the ends, crossed by a narrow band. — Am. I: 2 f. 4? Schum. Pr. 1). I 

 PI. IX f. 36? Cl. Diat. of Finl. p. 24 PI. I f. 3. H^rib. D. d'Auvergne p. 82 PI. IV f. 4. 



Fresh water: Sweden (Almten in Kalmar Ian)! Finland (Sodankyla)! Greenland! Puy de 

 Dome, fossil (Herib.), America (Maine, Brun Coll.)! 



59. P. latevittata Cl. N. Sp. — V. linear, with broad, rounded ends. L. 0,18; B. 0,033 

 mm. Median line not complex, oblique; terminal fissures comma-shaped. Axial area broad, less 

 than V3 of the breadth of the valve, widened in the middle. Striiw 6 in 0,oi mm., divergent 

 in the middle, convergent at the ends, crossed by a very broad band. — A. S. Atl. XLII f. 5. 



Fresh water: Puerto Monte, Chile, foss.! Ecuador! 



Var. Doniingensis Cl. — V. slender, gibbous in the middle and at the ends. L. 0, 15 to 

 0,36; B. 0,022 to 0,04 mm. Strite 6 to 8 in 0,oi mm. — A. S. Atl. XLIII f. 3. Cl. Diatomiste 

 II PI. VII f. 3. 



Fresh water: North America (Cherryfield, Atl.), West Indies, Jamaica and St. Vincent 

 (Grove Coll.)! San Domingo (Witt Coll.)! Ecuador! 



60. P. Dactylus Ehb. (1843). — V. subelliptic-linear, with rounded, obtuse ends. L. 0,17 

 to 0,32; B. 0,03 to 0,05 mm. Median line gently undulate, not complex. Central nodule large, 

 excentric; terminal fissures comma-shaped. Axial area moderately wide, al)out \/'., as broad as the 

 valve, irregularly linear-lanceolate. Stria", 4, .5 to 5 in 0,oi mm., crossed by a broad band. — Am. 

 p. 132 PI. IV: 1 f. 3. P. Gigas Ehb. Am. p. 133, II: 3 f. 1. NavicuJa Dactylus A. S. Atl. XLII 

 f. 3, 4, 6. Nar. Dae. forma maxima V. H. Syn. PL V f. 1. Nav. Gigas A. S. Atl. XLII f. 1. 



Fresh water: Sweden (Lapland to Halland)! Norway! Finland! Scotland (Premnay Peat)! 

 France (Lac Gerardmer Vosges)! America (common: most diatomaceous earths)! 



Var. horrida H]i;rib. a. Perag. (1893). — L. 0, 10 ; B. 0,o25 mm. Area with irregularly 

 scattered spines. Striee 7 in 0,oi mm. — Nav. maj. var. Jiorr. H^rib. a. Perag. D. d'Auvergne 

 p. 83 PL IV f. 3. 



Fresh water: Puy de Dome (fossil). 



Var. Denierarce Cl. — Linear, with subcuneate ends. L. 0,14; B. 0,o34 mm. Stria; 5,.') in 

 0,01 mm. — A. S. Atl. XLIII f. 29. 



Fresh water: South America (Demerara River)! 



Var. Dariana A. S. (1876). — V. lanceolate, with obtuse ends. L. 0, is to 0,21; B. 0,o4i 

 0,04 f) mm. Median line oblique, not complex, with comma-shaped terminal fissures. Axial area 

 broad, less than '/., of the breadth of the valve, widened in the middle. Striffi 7 to 8 in 0,o2 mm., 

 divergent in the middle, convergent at the ends, crossed by a broad band. — Nav. Dariana A. S. 

 Atl. XLII f. 24, 25. 



Fresh water: America, Crane Pond! Schasta Co. Calif.! Neu.se River (Atl.), Dai'ien (Atl.). 



VIII. Complexse. 



Artificial key. 



j Central area a transverse fascia 2. 



■^- \ — — not — — 4. 



