114 P. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



area large on tlie dorsal side. Strige 9 in 0,oi mm., ending at tlie longitudinal line. — D. of 

 Clyde p. 526 Pl. XIV f. 98? Icon. n. Pl. III f. 19, 20, 21. 



Marine: Porto Segiiro, Bahia (Deby Coll.)! Java! 



This form, which af all Amphoraj observed by me bas the greatest resemblance to Ä. pro- 

 ioscidea of G-regory, is nearly akin to Ä. Grmffii. 



18. A. biociilaia Cl. — Frustule elHptical with truncate ends. L. 0,o7; B. 0,o4 mm. 

 Zone with broad divisions (1,5 in 0,oi mm.) transversely striate; strise 17 in 0,oi mm. finely 

 punctate. V. lunate with broad, obtuse and incurved ends. Median line biarcuate. Axial area 

 narrow. Longitudinal line strong, bent from the central nodule. Striee 14 in 0,oi mm., costate, 

 and alternating with rows of puneta (15 in 0,oi mm.) faint on the space between the longitudinal 

 and median line. Ventral side structureless, broad. — Pl. Ill f. 36, 37, 38. 



Marine: Balearic Islands! Sumatra (Deby Coll.)! 



19. A. geminifera Petit (1888). — V. with arcuate dorsal and straight ventral margin. 

 Ends rostrate. L. O.oe to 0,072; B. 0, 00 8 to 0,oi2 mm. Axial area on the dorsal side narrow; 

 central triangulär, strise 7 in 0,oi mm. crossed by a longitudinal line, bent around the central 

 nodule. — D. de Cape Horn p. 120 Pl. X f. 12. 



Marine: Cape Horn (Petit). 



This species is unknown to the author, possibly a var. of A. Grevilleana or perhaps a var. 

 of the foUowing species. 



20. A. Sturtii Grun. (1888) — V. with straight ventral margin, gibbous in the middle, 

 sinuose dorsal margin and capitate ends. L. 0,i4; B. 0, 02 5 mm. Axial area narrow, central tri- 

 angulär. Strise 7 in 0, 01 mm. not distinctly punctate (on corroded specimens), crossed by a strong 

 longitudinal line bent around the central nodule. ■ — Bot. Centralbl. Bd. 34 p. 36. A. contracta? 

 Grove a. Sturt J. Quek. M. C. Vol. IH Ser. II p. 131 (1887) Pl. X f. 4. 



Marine: Oamaru, New Zealand, foss. (Grove Coll.)! 



21. A. subpunctata Grove and Sturt (1887). — V. with arcuate dorsal and straight ventral 

 margins, obtuse and incurved ends. L. 0,i9; B. 0,0 2 8 mm. Axial and central areas uniting on the 

 dorsal side in a broad semilanceolate space, covered with large and scattered döts. Longitudinal 

 line strong, bent from the central nodule. Strise 6 to 7 in 0, 01 mm. coarsely punctate. — J. 

 Quek. M. C. Vol. Ill Ser. II p. 131 Pl. X f. 3. 



Marine: Oamaru, New Zealand, fossil (Grove Coll.)! 



22. A. Leiidiigeriana Petit (1888). — V. narrow, with arcuate dorsal and straight ventral 

 margins. Ends rostrate-capitate, incurved. L. O, os to 0,ii; B. 0,oi4 to 0,oi6 mm. Median line 

 straight, approximate to the ventral margin. Axial area linear, rather broad. Longitudinal lines 

 two. Strise 7 to 8 in 0, 01 mm. not distinctly punctate. Ventral side not striate. — D. de Cape 

 Horn p. 119 Pl. X f. 13. 



Marine: Cape Horn (Petit) Magelians Strait! 



This form is nearly connected with small forms of A. areolata, from which it differs by 

 the broader axial area. 



23. A. areolata Grun. (1876). — Frustule rectangular, with slightly eonvex sides and 

 truncate ends. L. 0, 09 to 0,i6; B. 0, 02 to 0,o3,'j mm. Connecting zone with 2,5 to 3 divisions 

 in 0,01 mm., crossed by strong, transverse costse, a little closer than the costse of the valve. 

 V. with arcuate dorsal, and straight central, margins. Ends protracted, rostrate or subcapitate, 

 according to the position of the valve. Median line straight or slightly biarcuate, approximate to 

 the ventral margin. Axial area indistinct. Longitudinal lines two, strong, not bent around the 

 central nodule. Strise costate, 3,5 to 6,5 in 0, 01 mm. Intermediate spaces smooth or with a double 

 row of obsolete puneta. Ventral part not striate, but with a strong longitudinal iine. 



