168 



p. T. CLKVK, SYNOPSIS f)F THE NAVICULDID DIATOMS. 



p. 68 PI. LIV f. 345. A. 8. Atl. X f. 64 to 69; LXXI f. 6 to 9. V. H. Syn. p. 65 PL TIT f. 9 

 to 11. Ch/mbella Enri/onenia Heib. Consp. p. 110 (1863). Encyoncnia mnximitm Wartm. Rabh. Alg. 

 Eur. N:o 1248 (1862). 



Fresh or slightly brackish water: Sweden (Unlf of Pothiiia, from W^esterhotteii to Koslagen; 

 Lake Malaren)! Finland (Abo, Ijadoga)! England! Belgiuni (V. H.), Finance! Switzerland (Hrnn), 

 (rerman}^! Hungary (Plattensee, Grun.), Italy (St. Fiora, toss.). 



36. ('. (Eiicyoneina?) iuelegans Ch. N. Sp. — V. boat-shaped, with airuate dorsal margin, 

 straight or slightly concave ventral margin, and broad, I'onnded, somewhat retlexed ends. L. 0,05') 

 to 0,()f..5; K. 0,02 mm. Median line parallel to the ventral margin, very excentric. Terminal 

 fissures comma-lil<e; terminal pores near the ends. Axial area linear, rather broad. Stria' on the 

 dorsal side 10 (middle) to 12 (ends) slightly radiate; striu' on the ventral side S in 0,oi mm., 

 7'adiate in the middle, pai'allel in the ends, coarsely punctate; puncta 17 to 18 in 0,oi mm. — 

 PI. V f. 1. 



Fi'esh water: Fall River, Oi'egon, fo!^s. ((Trove Coll.)! 



37. ('. (EiicyiMUMiia) Ti-iaiigtiliini Ehb. (1845). — V. broad, asymmetrical, lanceolate with 

 acute ends. L. 0,o4 to '•,i).''); B. 0,00 uim. Median line straight, dividing the valve into a ventral 

 part half as broad as the dorsal. Terminal fissures in the ends of the \alve. Axial area very 

 narnnv; central area small or indistinct. Strict 9 to 11 in (l,iii mm. almost parallel or .-slightly 

 radiate in the ends, coarsely punctate; puncta about 10 in 0,oi mm. — Gloeoiiciiui TriaiH/iihtni 

 Ehb. Abh. 1845 p. 77. M. (1. XXXV A. 7 f. 10. Enn/0,1. Triang. Kutz. Sp. Alg. p. {\-l. A. S. 

 Atl. X f. 54; LXXI f. 10. 



Fresh water: North America, New York and Pen.saeola (Atl.), Michigan, Dakota and Lost 

 Spring Ranch CJalif. ! Tasmania, Campbell Town, fossil! 



3S. ('. (Kncyoneiua) tiirgida (iKEii. (1856). — V. lunate, with strongly arcuate dorsal, cen- 

 trally' gilibous ventral margin, and acute ends. L. 0,oft to 0,io; B. (),oi2 to 0,o2:i mm. Median 

 line straight, dividing the valve into a ventral part of about half the width of the dorsal. Ter- 

 minal fissuies in the ends, comma-like, turned downwards. Axial area distinct, linear, scarcely 

 dilated in the middle. Striie 7 to 9 in (>,oi mm., radiate in the middle and, on the dorsal side, 

 at the ends, parallel or convergent at the ends on the ventral side, punctate; puncta 13 to 18 in 

 0,01 mm. -^ Greg. M. .1. IV p. 5 PI. 1 f. 18. Enn/0,1. fur,/. A. S. Atl. X f. 49 to 53. V. H. Syn. 

 p. 65 PI. Ill f. 12. 



Fresh water: Sweden! Finland! Mouth of Jeni.ssey! Scotland (Greg.). East Indies! Java! 

 Australia (Murraj^ River)! Tasmania! New Zealand! North America ((California, Mexico)! Guate- 

 mala! Ecuador! Argentina! 



This species is very variable and graduates into tlie following. The largest and most ty- 

 pical specimens occur in ('alifornia, Mexico and Ecuador. European .specimens ai'e smaller and 

 can only with difficulty be distinguished from tlie foHowing species. 



39. C. (Eiu-youeiua) ventricosa KiiTZ. (1834). — V. lunate, with straight or centrally- 

 gibbous ventral margin and subacute ends, usually turned downwards. L. 0,oi.^ to O,o:ic, ; B. 0,007 

 to 0,011 mm. Median line appi'oximate to the ventral margin. Terminal nodules and fissures at 

 the ends of the valve. Axial area very narrow oi' indistinct. Striic 10 to 16 in O.oi mm. slightly 

 radiate, finely punctate. Frustules enclosed in branched mucous tubes. — Frnsful/a niUricosa KtJTZ. 

 Syn. ]). 11 f. 7. Ci/nih. reu. Bac. p. 80 PI. VI f. 16. Encyoii. ventric. V. H. Syn. p. ()6 PI. Ill fig. 15 

 to 17, 19. Enryoii. ]>rostratum KliTZ. Bac. p. 82 PL XXV f. 7 (1844). Encyon. ccfspHosnm KtiTZ. 

 Sp. Alg. p. 61 (1849). W. Sm. B. D. II p. 68 PL LV f. 346. V. H. Syn. p. 65 PL III f. 14; Suppl. 

 A f. 3. A. S. Atl. X f. 57, 58; LXXI f. 11, 12. Encyon. Aucrswahii, Rabh. Sussw. D. p. 24 PL VII 

 f. 2 (1853). Cynihella mantlafa W. Sm. B. D. I PL II f. 23. Cynth. affmis var. semicircularis 

 Lagst. Spitsh. 1). p. 43 PI. II f. 20. Cocconeimi LutiuJa Ehb. Am. PI I: 1. f. 15 (1843). Encyon. 



