KONGL. SV. VKT. AKADEMTKNR IIANDLlNGAIi. HAND 27. N:u 3. 105 



blank band across the stripe. Strise on the dorsal side 10 to 11 in Ojii mm. coarsely |iiiiiclate; 

 puncta about 8 in 0,oi mm., often uniting near the (!entral nodule. — yl. libyca Kiii',. IVr. 1840 

 p. 11 (fide Kiitz). KiiTZ Bac. p. 107. A. af finis KiJTZ Hac. p. 107. A. ovalis var. (if fin is V. H. 

 Syn. p. 59 PI. If. 2. A. ovalis A. S. Atl. XXVI f. 102 to 111; PI. XXVII f. 4, ;')? A. ahbre- 

 viafn Bleiscii Rabii. A. E. 1489 (1803). A. Szontaghii Pant. II p. 39 PI. VII f. 138? A. Proteus 

 var. A. S. Atl. XXVIII f. 1? A. Sfanbit Pant. HI PI. X f. 171 (1893)? A. verrwosa Pant. Ill 

 PI. X f. 166 (1893)? A. sraris Pant. Ill PI. XXVIII f. 416 (1893)? 



Fresh or brackish water: Spitsbergen (Atl.), Greenland! East Cape! Sweden! England! 

 France! Belgium (V. H.), flermany (Saline Diirrenberg! Konigsberg, foss. !) Hungary foss. (Pant.)? 



Var. Fediculus KtJTZ (1844). — Frustule in outline broadly elliptical. Valve lunate. li. 0,02 

 to 0,04; B. 0,006 to 0,008 mm. Median line slightly biarcuate. Central area distinct and central 

 nodule strong. Striiie 14 to 16 in 0,oi mm. coarsely punctate. Ventral side striate. — Cynihclhi'^ 

 Fediculus KtJTZ Bac. p. 80 PI. V f. 8. A. ovalis 8 Pediculus V. H. Syn. p. 59 PI. I f. 6. A. ovalis 

 y affinis f. minor {A. Pediculus major Grun.) V. H. Syn. p. 59 PI. I f. 4, 5. A. minntissima W. Sm. 

 B. D. p. 20 PI. II f. 30 (1853). A. horcalis ScnuM. P. D. I Nachr. p. 23 f. 31 (1863). A. (jlohosa 

 SCHUM. P. D. II Nachr. p. 55 PL I f. 24 (1867). A. sp. n.? A. S. Atl. XXVI f. 102. A. libyca var. 

 interru2')ta Pant. II p. 37 PI. II f. 28. 



Fresh or slightly brackish water, usually attached to larger diatoms, as Nitzschia sigmoidea, 

 or on algse: Sweden! Finland! England! Belgium! Germany! India (Atl.), New Zealand! Tasmania! 

 Hungary, fossil (Pant.). 



Although tliese varieties are at first sight very dissimilar to each others, they are so inti- 

 mately connected by intermediate forms that I am entirely of the opinion of Grunow and Van 

 Heurck that they should be united. 



13. A. perpusill.1 Grun. (1880). — Frustule in outline nearly orbicular. L. 0,oof> to 0,oi; 

 B. 0,004 to 0,o()."> mm. Valve lunate, with arcuate dorsal, and straight ventral, margin. Central 

 nodule .strong. Dorsal striai 16 to 20 in 0,oi mm. almost transverse. Central area usually not 

 distinct. Ventral side without striii;. — A. (globulosa var.) pcrpusilla Grun. V. H. Syn. PI. If. 11. 



A. perp. V. H. Types N:o 4. A. ovalis var. 6 Pediculus forma minor and exilis V. H. Syn. p. 59 

 PI. I f, 8, 9, 10. A. Pediculus A. S. Atl. XXVI f. 99. Cl. M. IJ. 126, 137. A. glolmlo.sa Schum. 

 Preuss. D. II Nachr. p. 55 PI. I f. 25. A. S. Atl. XXVI f. 100. 



Fresh water, moist earth etc.: Sweden (Upsala, Dalsland!) Prussia (Schum.), Belgium (V. H.), 

 England, Swansea! France, Meudon! Hungary, Plattensee (Atl.). 



14. A. mexicaiia A. S. (1875). — V. lunate with arcuate dorsal and straight ventral mar- 

 gin. L. 0,1. '■) to 0,20; B. 0,0:^.'^ mm. Median line more or less biarcuate. Axial area not distinct; 

 central area small and rounded on the dorsal side. Dorsal side with a longitudinal line more or 

 less approximate to the median line. Strise 6 to 8 in 0,oi mm. coarsely punctate; puncta 6 to 7 

 in 0,01 mm. Ventral side entirely covered with somewhat radiate .stritB. — A. S. Atl. XXVII 

 f. 47 to 48. Icon. n. PI. IV f. 15. A. boryana Pant. Ill PI. XXXVIII f. 531 (1893). 



Marine: Morocco! Gulf of Naples! Sumatra (Deby Coll.!), (Jhina! Galapagos Islands! Gulf 

 of Mexico (Atl.). 



Var. fusca Cl. — Zone with small irregular puncta giving it a brownish colour. L. 0,14; 



B. 0,075 mm. Striae 8 in 0,oi mm. 



Marine: Macassar Straits! 



I am not quite sure about the identification, as the fig. in Atl. shews a more distant 

 longitudinal line than in my specimens. A. lima A. S. Atl. Probetof. f. 14, which is unknown to 

 me, seems to be allied to A. mexicana. 



15. A. gigantea Grun. (1875). — Frustule broadly elliptical with truncate ends. V. lunate, 

 with straight ventral margin. L. 0,o9 to 0,i;; B. 0,02,') to 0,o3.t. Median line strongly biarcuate. 



K. Sv. Vet. Akad. Hauill. Bau.l 27. N:o 3. 14 



