539 





Grun. 

 ih the 



58. Navicula achnanthoides m. Fig. 113. """/i. L: 0.02 mm. 

 —0,08 mm.; B: 0,005 mm. 



Almost linear willi obtuse, sometimes very sliglilly contracted 

 apices. Striæ contiguous and exceedingly delicate, so that I have 

 nol been able to counl them; radiating and somewhat 

 distant in the middle, and convergenl towards the apices. 

 As far as I t-an see there is a central area. The frustule 

 slightly bent. 



I am uncertain as to the systematic position ol Ihis 

 form. Il has been impossible for me to distinguish any 

 structure of the striæ, bat the latter radiating and being 

 convergeni t tiis species mav be referable to Cleve's Navi- Fig. 113. 

 culæ lineolatæ. The outline of the valve and the somewhat 

 benl frustule remind one of Achnanthes tceniala Grun. (Cl. and 

 arc. Dial.. tab. I., fig. ."> , hid Ihe presence ol' central nodules in bo 

 valves proves thai il cannot be identical with the latter species. 



Found only in a few examples in a gathering Ironi Thorshavn 

 (S tro ra o). 



NAVICULÆ PUNGTATÆ CL, Cl. Syn. II, p. 37. 



59. Navicula pusilla W. Sm„ V. H. Syn. lab. II., lig. 17. 

 Rare. Ejde (Ost er o . 



NAVICULÆ LYRATÆ Cl, Cl. Syn. II.. p. 52. 

 00. Navicula Hennedyi W. Sm., V. H. Syn. tab. IX., lig. 14. 

 Rare. Skaalefjord Ost er 6). 



61. N. Reichardtii Grun., A. S. All. tab. LXX., lig. 28. 

 Rare. Thorshavn (Stromo). 



62. N. forcipata Grev., V. H. Syn. lab. X., lig. 3. 

 Rare. Klaksvig Bordo); Vestmanhavn (Stromo). 



NAVICULÆ LÆVISTRIATÆ Cl, Cl. Syn. II.. p. 66. 



63. Navicula palpebralis Bréb., Donk. Brit. Diat. lab. IV., lig. 3 b. 

 Rare. Skaalefjord Oste ro ; between Thorsvig and Kvalvig. Kaibak- 

 fjord (Stromo . 



A few of the specimens somewhat approach the variety: angulosa 

 Greg., Donk.. 1. c. lig. 4. 



PIXNULARIA Khr.. Cl. Syn. IL, p. 71. 

 Capitatæ CL, 1. c p. 75. 

 *64. Pinnularia mesolepta Klir. var. stauroneiformis Grun. A. S., 

 Atl., tab. XLV., ligs. 52—53. 

 Tværaa Sy de ro). 



