114 p. T. CLEVE, SYNOPSIS OF THE NAVICULOIl) DIATOMS. 



area large on the dorsal side. Stria' !» in 0,01 nun., ending at the longitudinal line. — D. uf 

 Clyde p. 526 PI. XIV f. 98? Icon. n. PL. Ill f. 19, 20, 21. 



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



This form, which af all Amphorae observed by me has the greatest resemblance to A. ])ro- 

 boscidea of (xregory, is nearly akin to A. Grceffii. 



18. A. biociiliita Cl. — Frustule elliptical witli truncate ends. L. (1,07; B. O.04 mm. 

 Zone with broad divisions (1,5 in (),oi mm.) transversely striate; striffi 17 in 0,01 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. Stria; 14 in O.ui mm., costate, 

 and alternating witli rows of puncta (lo in 0,oi mm.) faint on the space between the longitudinal 

 and median line. Ventral side structureless, broad. — PI. Ill f. 3(!, 37, 38. 



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



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

 Ends rostrate. L. O.or, to 0,0:2; B. 0,no8 to O,oii mm. Axial area on the dorsal side narrow; 

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

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



Marine: Cape Horn (Petit). 



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

 of the following 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. O.oii.^ mm. Axial area narrow, central tri- 

 angular. Striffi 7 in 0,oi 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. Ill Ser. II p. 131 (1887) PI. X f. 4. 



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



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

 margins, obtuse and incurved ends. L. 0,i9; B. 0,028 mm. Axial and central areas uniting on the 

 dorsal side in a itroad semilanceolate space, covered with large and scattered dots. Longitudinal 

 line strong, bent from the central nodule. Stria; 6 to 7 in 0,oi mm. coarsely punctate. — J. 

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



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



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

 margins. Ends rostrate-capitate, incurved. L. 0,08 to 0,ii; B. 0,oi4 to 0,oi(; mm. Median line 

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

 two. StricE 7 to 8 in 0,o 1 mm. not distinctly punctate. Ventral side not striate. — I), de Cape 

 Horn p. 119 PL X f. 13. 



Marine: Cape Horn (Petit) Magellans Strait! 



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

 the broader axial area. 



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

 truncate ends. L. 0,09 to 0,i6; B. 0,o2 to 0,035 mm. Connecting zone with 2,5 to 3 divisions 

 in 0,01 mm., crossed by strong, transverse costs;, a little closer than the co.st<E 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. Striae costate, 3,5 to 6,5 in 0,oi mm. Intermediate spaces smooth or with a double 

 row of obsolete puncta. Ventral part not striate, but with a strong longitudinal line. 



