112 P. T. CLEVE, SYNOPSIS OF THE NAVICULOII) DTATOMS. 



10. A. Griindleri Grun. (1875). — Frn.stule rectangular, with broad, truncate ends. L. 0,o6 5 

 to 0,136; B. 0,03 to 0,0.5 mm. Zone witli several longitudinal divisions, about 3 in 0,oi mm., 

 transversely striate; strige 9 to 10 in 0,oi mm. Median line strongly arcuate. V. linear with 

 prominent, subcapitate and incurved ends. Dorsal side with 9 to 10 indistinctly punctate strise 

 in 0,0 1 mm., not reaching to the median line and crossed by a narrow longitudinal band. Ventral 

 side with two rows of puncta, one aloug the median line and one near the ventral margin. — 

 A. S. Atl. XXVIII f. 24 to 27; XXXIX f. 25. 



Marine: Gulf of Naples! Madagascar! Colombo, Ceylon (Le Tourneur ColL), Manilla (Deby 

 Coll.)! Galapagos Islands! Campeachy Bay! Gulf of Mexico! Fossil: Hungary (Pant.). 



Var. trachytica Pant. (1889). — V. in L. 0,o9 to O, i; B, 0,oi5 mm. Strise on the dorsal 

 side reduced to two rows of puncta. — Pant. II p. 37 Pl. VII f. 132. 



Marine: Hungary, fossil (Pant.). 



Var. approximata Cl. — V. in L. 0, 13; B. 0,oi7 mm. Dorsal strise 12 in 0, 01 mm. Ventral 

 rows of puncta approximate to the median line. 



Marine: Island of Rhea, near Singapore (Van Heiirck Coll.)! 



Var. robusta Cl. — V. in L. 0,i to 0,17; B. 0,02 to 0, 03 mm. Strise fi to 7 in 0, 01 mm. 



Marine: Nossibé (Brun Coll.)! Macassar Straits (Grove Coll.)! Fossil: Oamaru, N. Zealand 

 (Grove Coll.)! 



11. A. prismatica Cl. N. sp. — V. elongated, with prominent, rounded and incurved ends. 

 L. 0,12 to 0, 17; B. 0,018 to 0,0 2 7 mm. Dorsal side with distinct axial area and several longitu- 

 dinal blank bands. Strise not distinctly punctate, 10 to 12 in 0, 01 mm. Ventral side with two 

 longitudinal rows of short stria^,. — Pl. IV f. 2fi. 



Marine: Gulf of Naples (Deby Coll.)! Oamaru, N. Zealand, fossil (Grove Coll.)! 



12. A. diapliana Cl. N. Sp. — Frustule elliptical, with truncate ends. L. 0,o4s; B. 0,027 

 mm. Zone complex, its divisions about 7 in 0, 01 mm., striate. Striee 14 in 0,oi mm. V. with 

 strongly arcuate dorsal and straight ventral margin; ends not protracted. L. 0,048 to 0,065; B. 0,oi 

 to 0,0 17 mm. Median line strongly biarcuate. No axial area on the dorsal side, where there is 

 close to the median line a strong longitudinal line. Strite 15 in0,oi mm. finely punctate. Ventral 

 side structureless, broad, with a longitudinal line. — Pl. IV f. 27. 



Marine: Java! Colon (Deby Coll.)! 



13. A. truiicata Greg. (1857?) Cl. — Frustule elliptical with truncate ends. L. 0,o5 to 

 0,055; B. 0,025 to 0,028 mm. Zone with about 4 divisions in 0, 01 mm., transversely striate; strise 

 22 in 0,01 mm. V. with arcuate dorsal margin and straight ventral margin. Ends not protracted. 

 Axial area moderately broad on the dorsal side. Strite 19 to 20 in 0,oi mm. Ventral side struc- 

 tureless, or with faint traces of striation. — D. of Clyde p. 515 Pl. XIII f. 77? Icon. n. Pl. III 

 f. 17, 18. 



Marine: Finmark! Sebastopol! 



What A. truncata Gkeg. may exactly denote is not possible to make ont without original 

 specimens, but it is certainly a form neaiiy akin to A. Grcvilleana. The same may be the case 

 with A. fjuadrata Greg. (D. of Clyde p. 521 Pl. XIII f. 85) and also with A. snlcata Bréb. (1854). 



14. A. sulcata (Bréb. 1854)? Cl. — Frustule elliptic-rectangular, with ti-uncate ends. 

 L. 0,053 to 0,06; B. 0, 026 mm. Zone with about 3 divisions in 0, 01 mm., striate; strite 15 to 16 

 in 0,01 mm. V. with arcuate dorsal and straight ventral margin. Axial area distinct on the dorsal 

 side of the median line. Striaj 11 to 12 in 0,o 1 mm. Longitudinal line indistinct. Ventral side 

 structureless. Longitudinal line not distinct. — Bréb. Notes sur quelques D. de Cherb. f. 8 (1854)? 



Marine: Balearic Islands! 



As above stated it is impossible to make out what form Bréhisson denotes by the name 

 A. sulcata, for which reason I have adopted this name for a form, which in all points is nearly 



