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



linear, central axial area, on one side of which, in the middle of the valve, there is a horseshoe- 

 shaped area. Stripe 13 in 0,oi mm. almost parallel, coarsely punctate. Lower V. with narrow 

 axial area and broad, quadrate or rectangular central area. Striae 14in0,oi mm., slightly radiate, 

 coarsely punctate. — Achnanthidium lanceolatum Kutz. Sp. Alg. p. 54. W. Sm. B. D. II PI. XXXVII 

 f. 304. Achnanihes lane. Grun. A. D. p. 23. V. H. Syn. p. 131 PI. XXVII f. 8 to 11. Stauro- 

 neis truncata Schtjm. Preuss. D. I Nachtr. p. 22 f. 28. 



Fresh water: Throughout Europe! Amsterdam Island! Tasmania! New Zealand! Australia 

 (North Australia, Daintree River, Australian Alps)! Illinois! Ecuador! 



Var. dubia Grun. (1880). — Broadly lanceolate. L. 0,oi5 to O.oiv; B. 0,oo7 to 0,oo72 mm. 

 Striae 13 to 14 in 0,oi mm. — A. D. p. 23. V. H. Syn. p. 132 PI. XXVII f. 12, 13. 



Eresh water: Belgium (V. H.), Austria (Grun.)! 



Var. elliptica Cl. (1891). — Elliptical. L. 0,oi2 to 0,oi6; B. 0,oo7 to 0,ooo mm. Upper V. 

 with 16 strise in 0,oi mm. — D. of Finland p. 51 PI. Ill f. 10, 11. 



Fresh water: Abo in Finland! 



Var. Haynaldii Saarsch. (1881). — Inflated in the middle, with rostrate-capitate ends. L. 

 0,025 to 0,027*, B. 0,007 mm. Strife 16 in 0,oi mm., indistinctly punctate. — Achn. Haynaldii Saarsch. 

 Spec. Phyc. Aeqnat. p. 8 (according to De Toni Syll. p. 478). Cl. Diatomiste II PL VII f. 14. 



Fresch water: Ecuador, Antisana! 



3. A. Peragalli Brun. a. H^rib. (1893). — Broadly elliptical, inflated, with protracted api- 

 culate or subcapitate ends. L. 0,oi2 to 0,oi6; B. 0,oo6 to 0,oo8 mm. Upper V. with narrow, 

 linear and central axial area, on one side of which in the middle of the valve there is a horseshoe- 

 shaped area. Strise 17 in 0,oi mm. slightly radiate. Lower V. with large, outward dilated central 

 area. Strise very fine and oblique. — D. d'Auvergne p. 50 PI. I f. 4. 



Fresh water: Puy de Dome, living (Brun. Coll.)! 



A very small, but distinct species, resembling A. lane. var. Haynaldii. 



4. A. mesogongyla Grun. (1879). — Narrow, elongated, inflated in the middle, with rounded 

 ends. L. 0,08 to 0,0 9; B. 0,oi3 to 0,oi4 mm. Upper V. with central, narrow axial area and 

 transverse, coarsely punctate strife, 10 in 0,oi mm. (puncta 18 in 0,oi mm.). Lower V. with broad 

 central fascia. Strife 11 in 0,oi mm. punctate; puncta 18 in 0,oi mm. — Cl. M. D. N:o 193. 

 A. D. p. 19. Icon. nost. PI. Ill f. 2. 



Fresh water: Brazil! 



5. A. coarctata Br^b. (1855). — Linear, slightly constricted in the middle, with broad, 

 truncate ends. L. 0,04; B. 0,oo8 mm. Upper V. with very excentric, narrow, frequently infra- 

 marginal, axial area. Strise 11 to 14 in 0,oi mm. punctate. Lower V. with broad central fascia. 

 Striae 12 to 15 in 0,oi mm. slightly radiate, punctate. — Achnanthidium coaret. Ann. Mag. Nat. 

 Hist. [2] Vol. XV p. 8 f. 10. W. Sm. B. D. PL LXI f. 379. Achnanthes coaret Grun. A. D. 

 p. 20. V. H. Syn. p. 130 PL XXVI f. 17 to 20. Achnanthidium eoaret. var. elineata Lagst. 

 Spitsb. D. p. 49 PL I f. 16. Achn. hinodis Ehb. M. G. PI. XXXIV, 5, B, 12. 



Fresh water, moist earth, on mosses: Spitsbergen! Beeren Eiland (Lagst.), Arctic America! 

 Sweden (Upsala)! England! France! Belgium (V. H.). 



6. A. inflata Kutz. (1844). — Elongated, gibbous in the middle, with rounded capitate ends. 

 L. 0,045 to 0,065; B. 0,oi5 to 0,018 mm. Upper V. with very excentric axial area. Striae 9 to 

 10 in 0,01 mm. parallel, composed of coarse puncta, about 9 in 0,oi mm. Lower V. with broad 

 fascia. Striae about 10 in 0,oi mm. slightly radiate; puncta about 10 in 0,oi mm. — Stauroneis 

 inflata Kutz. Bac. 105 PL XXX f. 22. Achnanthes ventrieosa Ehb. M. Geol. p. 226. Monogramma 

 ventr. Ehb. M. Geol. PL I, II, f. 9, PL III f. 18, 19, b, e. Grev. T. Bot. Soc. Edinb. Vol. VIII 



