KONGL. SV. VKT. AKADEMIKNS IIANDLINGAK. I5ANI) 27. N:<) 3. 7 



4. A. Macraeaiia Pant. (1889). — V. rhomboid-lanceolate, gradually tapering to the not pro- 

 tracted ends. L. (),ii9 to 0, 17; B. 0,027 to t),03;j mm. Axial area narrow linear. Central area a 

 transverse fascia, reaching on one side to the margin, on the other nearly to the margin. StrifU 

 18 in 0,01 mm., transverse in the middle and convergent at the ends, composed of elongated 

 pnncta forming undulating, longitudinal rows, about 14 in 0,0 1 mm. — Nav. Macraeana Pant. II 

 PI. VIII f. 155. 



Brackish water: Hungary, Gryiingyos Pata! 



5. A. menilitica Pant. (1889). — V. lanceolate with rostrate, obtuse ends. L. i),o:\»; 

 B. 0,0 16 mm. Axial area linear. Central area a transverse fascia. Striae 20 in 0,oi mm. com- 

 posed of distant pnncta. — N. menil. Pant. II p. 51 PI. II f. ;!0. 



Brackish water: Hungary, fossil (Pant.). 



I have not seen this form, which seems to be nearly akin to A. sphcerophora var. biceps. 

 Nav. irrorata car. fossilis Pant. (PI. VIII f. 147) seems to be also related to the above species. 



6. A.? serians Br^b. (1844). — V. rhomboid-lanceolate with acute ends. L. 0,o6 to 0,o8; 

 B. 0,012 mm. Axial area linear-lanceolate. Strijc 24 in 0,oi mm. slightly radiate throughout, 

 compo.sed of elongated pnncta, forming longitudinal rows. — Navicula serians Br^b. in KuTZ Bac. 

 p. 92 PI. XXX f. 23. W. Sm. B. D. XVI f. 130. Donk. B. D. p. 41 PI. VI f. 10. Grun. Verh. 

 1860 PI. V f. 13. V. H. Syn. p. 101 PI. XII f. 7. N. lincolata EiiB. 1843 fide KtJTZ. N. punctu- 

 lata Ehb. M. Gr. XVI: i, f. 1 1854. 



Fresh water, northern or alpine regions: Greenland I Lapland! Scotland! England, Cornwall! 

 Belgium (V. H.), Switzerland! Sierra Nevada! New Hampshire (foss.)! Blue Mountains, Australia! 

 New Zealand (foss)! 



This well-knoAvn species occurs rarely living except in nothern or alpine regions. It is of 

 frequent occurence in diatomaceous earths from Scandinavia and North America. 



7. A.? bracliysira (Bheb. 1853) (tRun. — V. rhomboid, more or less obtuse. L. 0,022 to 

 0.028; B. 0,006 to 0,009 mm. Axial area narrow; central small. StrirC 26 to 27 in 0,oi mm. — 

 Navicula brachjsira Br^b. in Pabh. Stlssw. D. p. 39 PI. V f . 11 c, d, e. GtRUN. V. H. Types N:o 

 39. C. serians v. minor and minima GtRUN. in V. H. Syn. PI. XII f. 8, 9. Cymhclla Beverleiana 

 A. S. Atl. LXXI f. 56 to 61 (1881). 



Fresh water: Grreenland! Lapland! Finland! Scotland! 



A. brachysira in V. H. Syn. Suppl. B f. 31 seems, so far I can see, to be the same as A. serians, 

 A. brachysira differs from A. serians only in its smaller size, its somewhat finer strict and espe- 

 cially its obtuse ends. There is a tendency to asymmetry in the valves, which induced A. S. to 

 regard such forms as belonging to Cymbella. _ 



8. A.? zellensis Grun. (I860). — V. linear, slightly biconstricted, with rostrate, broad and 

 obtuse ends. L. 0,032; B. 0,00.=) mm. Striae 30 in 0,oi mm. Axial area indistinct; central small. 

 — Nav. zellensis Grun. Verh. 1860 p. 521 PI. Ill f. 34. V. H. Syn. PI. XII f, 14. N. tabida Ry- 

 lands (according to Grunow). 



Fresh water: Germany, Erlaf See (Grun.), Scotland! Greenland! Michigan! 

 This form is nearly connected with A. brachysira and A. serians. 



9. A.? Follis Ehb. (1838). — V. rhomboid, with strongly dilated middle, and obtuse, usuall}^ 

 capitate ends. L. 0,04; B. 0,017 mm. Central area small, lanceolate. Strise 24 in 0,oi mm., radiate 

 in the middle, transverse in the ends. — Navic. Follis Ehb. Inf. p. 179 M. G. XVI: 1, f. 14 etc. 

 DoNK. B. D. p. 44 PI, VI f. 15. N. Trochus KtiTZ Bac. p. 99 PI. Ill f. 59. 



Fresh water: Sweden (Lapland, Smaland)! Finland! Scotland! Norfolk, England (Donk.) 

 New Hampshire! Sierra Nevada! 



