KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 27. N:0 3. 123 



Var. limbata Cl. — Frustiile in L. 0,05 to' 0,o8; B. 0,03 to 0,o5 mm. Strite of the zone 



10 to 11 in 0,01 mm. V. in L. 0, 09; B. 0,oi.'5 mm. Strise 7 in 0, 01 mm. Dorsal side with a 

 narrow hyaline limbus. 



Marine: Indian Ocean (Deby Coll.)! China (Deby CoU.)! 



18. A. oxigiia GrREG. (1857). — Frustule linear-lanceolate, with rostrate, truncate ends. 

 L. 0,025 to 0,04; B. 0,011 to 0,012 mm. Zone with abont 8 divisions in 0, 01 mm. delicately striate; 

 stripe 17 to 20 in 0,oi mm. V. with arcuate dorsal, straight ventral, margins and rostrate, capitate 

 ends. StrijE 12 to 14 in 0, 01 mm. not distinctly punctate. Median line close to the ventral 

 margin. — D. of Cl. p. 514 Pl. XII f. 75. 



Brackish and marine: Scotland (Greg.), Arctic America! Bessels Bay! Adriatic! Sandwich 

 Islands! Tahiti! West Indies! 



A. exigua is figured by Gregory in a manner which admits of no trustworthy identification, 

 but as the stri<3e are stated to be 11 in 0, 01 mm. I believe that Gregory denotes this species, 

 which differs from smaller forms of A. acutiuscula in its smaller size, more delicately striate zone, 

 and not distinctly punctate stripe. 



19. A. granulata Greg. (1857). — Frustule linear-lanceolate, with rostrate, truncate ends. 

 L. 0,038 to 0,04 (0,043 to 0,077 Greg.); B. 0,oi3 to 0,oi8 (0,02 to 0,o33 Greg.) in 0,oi mm. Zone 

 with 7 to 11 divisions in 0,oi mm. and longitudinal rows of large pnncta, 10 to 13 in 0,oi mm. 

 V. with straight median line, closely approximate to the ventral margin. Strise 13 (10 to 14 Greg.) 

 in 0,0 1 mm. not distinctly punctate. — D. of Clyde p. 525 Pl. XIV f. 96. 



Marine: Java! Macassar Straits! 



20. A. Jeschkei Jan. (1876). — Frustule about 3 times longer than broad, with triundulate 

 margins and broadly truncate ends. L. 0,04; B. 0,oi35 mm. Zone with about 4 longitudinal rows 

 of large puncta (about 11 in 0,oi mm.) in 0,oi mm. Valve narrow with protracted and capitate, 

 incurved ends. Strise 12 in 0,oi mm. — A. S. Atl. XXXIX f. 14. 



Marine : ? 



21. A. turgida Greg. (1857). — Frustule in outline almost orbicular, with rostrate ends. 

 L. 0,025 to 0,035; B. 0, 015 to 0,02 mm. Zone with longitudinal divisions. V. in L. 0,02 to 0,04; 

 B. 0,00 7 5 to 0,009 mm. with broad, arcuate dorsal margin, straight ventral margin and rostrate 

 ends. Median line close to the ventral margin. Strife 13 (9 Greg.) in 0, 01 mm., not distinctly 

 punctate. — D. of Clyde p. 510 Pl. XII f. 63. A. S. Atl. XXV f. 24, 25. 



Marine: Scotland (Greg.), Norway! Hed Sea! Java! Macassar Straits! LabuanI 

 A. turgida is nearly akin to A. exigua, differing scarcely in anything but its greater breadth. 

 Grunows a. fluniinensis (Verh. 1863 p. 12 Pl. XIII f. 15) agrees in size and outline with A. turgida, 

 but has closer strise., 21 in O.oi mm. The latter species is unknown to me. 



22. A. Grunowii A. S. (1874). — V. broad with straight ventral margin and elevated, 

 slightly triundiilate dorsal margin. Ends capitulate. L. 0,054; B. 0, 021 mm. Strise 10 in 0, 01 mm. 

 composed of large, distant pnncta. Median line closely approximate to the ventral margin. — 

 Atl. Probet. f. 15. 



Marine: Java (Atl.). 



23. A. corpiilenta Cl. a. Grove (1891). — V. with almost straight ventral margin, very 

 elevated dorsal margin, and acuminate ends. L. 0,o96; B. 0,045 mm. Median line close to the 

 ventral margin. Dorsal side with 6 strise in 0, 01 mm. composed of distant puncta (4 to 5 in 0, 01 

 mm.). Ventral side very narrow, with about 8 strise in 0, 01 mm. — Diatomiste I p. 68 Pl. X f . 14. 



Marine: Macassar Straits! 



L 



