KOKGI.. SV. VKT. AKADKMIKNS IlANDLlNCAIi. BAND 27. \:() 3. 1^8 



Tliis snbgcims conipiiscs forms, wliicli apjx'ar not to be very closely coiinectfd. yl. /tif/xr- 

 horcd seems to be jikin to the linear forms of Microncls. A. (/ibberula and A. Jlolsfii are probably 

 allied to the section Mcsoleia; of Naricula and ought perhaps to be placed by the side of (J. mi- 

 ntifd. To C. (jitarncrcnsiti and the others I am unable to iind any allied i'or'ms among the Navicula;. 



Artificial knf. 



f Valve linear A. hypcrhorfd fiiiUN. 



1. — lanceolate or rlioinlioidal 2. 



I — elliptical f). 



y j Area of the uiiper valve granulatt! A. Lilljebergii Grun. 



\ — — — — not — 3. 



o I Upper valve with an horse.shoe-like mark A. Vasznryi Pant. 



( — — without — • — — 4. 



. j Stria; of the u|)per valve 22 in U,oi mm A. gibhenila Grun. 



■ 1 - — — — U — — '.A. Holstii Ci,. 



I L. about 0,01 mm fi. 



i). ^ 



\ L. 0,02 mm. or more 7. 



. I Striib of the upper valve unilaterally interrupted A. aniericana C'l. 



I — — — — not — — C. pygmcea Schum. 



_ j Upper valve with an hor.seshoe-like mark A. Lagerheimii Cr.. 



1 — — without — — — 8. 



J Striie of the u])[)er valve il in 0,01 mm C quarnemifiln Grun. 



'■ 1 — — — — 11 to 12 in O.oi mm 9. 



J j Area of the upper valve dilated in the middle C. hiharensi-s Pant. 



"' 1 — — — — not — — — C. Pelta A. S. 



1. A. Vaszaryi Pant. (l.Si'o). — Outline rhomboid, subacute. L. 0,o6; B. O.o.-j mm. Uppei' 

 V. unknown. Lower V. with narrow axial area and transverse, outwardly fimbriate central area. 

 Median stria' transverse and of uuequal length, 13 in 0,oi mm. Other striai strongly radiate 

 throughout, about 20 in 0,oi mm., punctate. — Nar. Vas^ari/i Pant. Ill PI. XVI f. 239. 



Habitat? Nyermegy (Pant.). 



Var. oregonica Ol. (1893). — Outline lanceolate with subrostrate, obtuse ends. L. 0,o.s; 

 B. 0,0 1.? mm. Upper V. with lanceolate axial area, a third as broad as the valve, and with a 

 unilateral horseshoe-shaped marking. OostiB slightly radiate, about 16 in 0,oi mm. alternating 

 with fine o])liquely arranged puncta, about 30 in 0,oi mm. Lower valve without axial area and 

 with a large central area, fimbriate outwards. Median striffi of unequal length and transverse, 

 about IS in 0,oi mm. Strife of the other portions of the valve very radiate, becoming closer 

 towards the ends, about 2() in 0,01 mm. — DIatomiste TT p. 57 PI. Ill f. 15, 16. 



Fresh water: Oregon, fossil' 



This is a very interesting species, the lower valve of which perfectly resembles that of 

 Actinoneis. It appears to be akin to A. Jietrroniorpha of the subgenus Acfinoncis. There can l)e 

 no doubt that Nav. Vaszaryi Pant., which represents the lower valve, is very nearly related to 

 the form from Oregon, of which I have examined an entire frustule. The differences are slight, 

 as to the size, the outline, and the coarseness of the striation, for which reason 1 am not inclined 

 to consider them as distinct species. 



2. A. hyperborea Gkun. (18(S2). Outline linear, with bi'oad, sometimes cnneate, ends, 

 slightly constricted in the middle. L. 0,026 to 0,028; B. 0,oo(;.-) to O.oos mm. slightly arcuate. 

 Upper V. with obsolete median line and broad, linear area. Striae 27 in 0,oi mm., radiate at the 

 ends. Lower V. without areas. Median strife 24, terminal 30 in O.oi mm. — Cl. M. I). N:o 314. 

 Franz Josefs Land U. p. 102 PL I f. 4, 5. 



Marine: Franz Josefs Land (fTrun). 



