§é P. T. CLEVE, SYNOPSIS Of THE NAVICUI/OID DIATOMS. 



distant on the depressions (8 in 0,oi mm.) than towards the margin and the median line (18 in 

 0,01 mm.). — Diatomiste I p. 67 Pl. X f. 10. 



Marine: Macassar Straits! 



This form is perhaps to be considered as a distinct species. 



49. N. impressa G-run. (1875). — V. elliptic-lanceolate. L. 0,o6 to 0,075; B. 0,o34 to0,o45 

 mm. Axial area indistinct, central area small. Strife 7 to 9 in O.oi mm. parallel in the middle, 

 slightly radiate at the ends. Pnneta coarse, 7 to 11 in O, di min. On both sides of the median 

 line are large Innate depressions. — A. S. Atl. VI f. 17, 18. 



Marine: Campeaehy Bay! Snmbava (Kinker Coll.)! 



50. N. sparsipunctata (tROvb and Sturt (1886). — V. broadly elliptical, with rounded ends. 

 L. 0,05 to 0,065; B. 0,0.3 to 0,04 mm. Central nodule very small. Terminal fissnres indistinct. 

 Axial area narrow, liiiear, nnilateral. Central area indistinct. Stria; 10 in 0,oi mm. parallel in the 

 middle, radiate at the ends. Pnneta coarse. ineqnidistant, about 6 in 0,oi mm. At some distance 

 from the margin is a narrow, not pnnctate, space. — Quek. M. Cl. II (2) p. 323 Pl. XVIII f. 1. 



. Marine: Oamaru, New Zealand, fossil! 

 This is a very remarkable form, not closelj^ akin to any known species. The median line 

 and the central nodnle are especially peculiar. 



51. N. interlineata G-rove and Sturt (1886). — V. elliptic-lanceolate. L. 0,i; B. 0,o5 mm. 

 Axial area narrow, very slightly dilated around the central nodnle. Terminal fissures indistinct. 

 StrisB 8 in 0, 01 mm., radiate throughout. Pnneta 8 in O.oi mm. forming irregularly undulating 

 rows. On both sides of the median line is a narrow, arcuate, lateral area, inside which the puncta 

 form more regular longitudinal rows. — J. Quek. M. Cl. II (2) p. 323 Pl. XVIII f. 2. 



Marine: Oamaru, New Zealand, fossil! 



A very remarkable species, which shews some resemblance to Diploneis nitida. 



52. N. fraudulenta A. S. (1881). — V. elliptical with rounded ends. L. 0,o3 to 0,045; 

 B. 0,0 19 to 0,0 2 3 mm. Axial area indistinct. Central area small, not sharply defined. Strise 14 

 (middle) to 18 (ends) in 0, 01 mm. slightly radiate at the ends, composed of puncta, about 13 in 

 0,0 1 mm., disposed towards the median line in straight, somewhat distant, longitudinal rows. — 

 N. S. D. III p. 18 (without name). N. fraudulenta A. S. Atl. LXX f. 60. N. restituta A. S. 

 accord. to Grun. in Cl. M. D. N:o 102 (1878). 



Marine: North Sea! Sebastopol! 



A small, very distinct species, not to be mistaken for any other. 



53. N. Novae Gruiueseiisis Temp. (1891). - V. broad, bieonstricted apicnlate. L. 0,o4 to 0,05; 

 B. 0,027 mm. Central nodule transversely dilated. Axial area narrow, linear. Central area trans- 

 versely dilated. iStrife 11 in O.oi mm., strongl}' radiate at the ends, composed of coarse puncta, 

 about 7 in 0, 01 mm. forming undulating longitudinal rows. — Diatomiste I p. 71, Pl. XI f. 1. 



Brackish water: Yule Island (New Guinea)! 



This is a very interesting form, not closely connected with any other. The median line 

 has somewhat arcuate coinponents, which suggests that tlie valve is slightly genuflexed as in 

 Achnanthes. The coarse striicture resembles that of Nnr. Tuscula, but the direction of the termi- 

 nal row.s of puncta is different and there is no appearance of a lineation across the puncta. The 

 dilated central nodule, as vvell as the strongly inclined stria;, remind one of the lower valve of 

 Arlnnmthrs danira and its allies, tint the striicture is miidi coarser and the valve strongly silicious. 



54. N. Pi Ch. (1893) — V. rliombic-lanceolate, witli obtuse ends. L. O, os; B. 0,0-22 mm. Axial 

 urea indistinct; central area small. Terminal lissures in the same direction. Strise 11 (middle) to 



