KONGL. SV. VET. AKADEMIENS IIANDLINGAU. RANI) 27. Nro 3. 123 



Var. limhata Cl. — Frustule in L. 0,05 to (),08; B. 0,03 to (),o5 miu. Striif of tlio zone 

 10 to 11 in 0,(11 mm. V. in L. 0,o9; B. 0,015 mm. Striae 7 in 0,oi mm. Dorsal side with a 

 narrow hyaline limbus. 



Marine: Indian Ocean (Deby ('oil.)! China (Deby Coll.)! 



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

 L. 0,025 to 0,04; B. 0,01 1 to 0,012 mm. Zone with about 8 divisions in 0,oi mm. delicately striate; 

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

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

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



Bi'ackish and marine: Scotland ((Treg.), Arctic America! Bessels Bay! Adriatic! Sandwich 

 Islands! Tahiti! West Indies! 



A. cxigua is figured by GtREgory in a manner which admits of no trustworthy identification, 

 but as the strife are stated to be 11 in 0,oi mm. I believe that Grehory denotes this species, 

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

 and not distinctly punctate striae. 



19. A. ffraimiata Greg. (1857). — Frustiile 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 0,033 Greg.) in 0,oi mm. Zone 

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

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

 in 0,0 1 mm. not distinctly punctate. — I), of Clyde p. 525 PI. XIV f. 9(5. 



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,o4; 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. Strife 12 in 0,oi mm. — A. S. Atl. XXXIX f. 14. 



Marine:? 



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

 L. 0,025 to 0,035; B. 0,oi5 to 0,02 mm. Zone with longitudinal divisions. V. in L. 0,o2 to 0,o4; 

 B. 0,007 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,oi mm., not distinctly 

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



Marine: Scotland (Greg.), Norway! Red Sea! Java! Macassar Straits! Labuan! 



A. tnrgida is nearly akin to A. exigua, differing scarcel}^ in anything but its greater breadth. 

 Grunows ^4. fluminensis (Verb. 1863 p. 12 PI. XIII f. 15) agrees in size and outline with A. turgida, 

 but has closer striae, 21 in 0,oi mm. The latter species is unknown to me. 



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

 slightly triundulate dorsal margin. Ends capitulate. L. 0,054; B. 0,02i mm. Striae 10 in 0, 01 mm. 

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

 Atl. Probet. f. 15. 



Marine: Java (Atl.). 



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

 elevated dorsal margin, and acuminate ends. L. 0,o9 6; B. 0,04 5 mm. Median line close to the 

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

 mm.). Ventral side very narrow, with about 8 strife in 0,oi mm. — Diatomiste I p. 68 PI. X f. 14. 



Marine: Macassar Straits! 



