The Diatoms of Nebraska 83 



5. Palpebrales 



45. Navicula palpebralis Breb. in W. Sin. Brit. Diat., /, p. ^o, 



pi. 31, fig. 223. 1853. 



PI. 9, figs. 363-365. 



Elliptic-lanceolate with acute apices, 27-80 /a long, 8-16 /x. wide; 

 striations radiate, very short, leaving a lanceolate hyaline space 

 along the raphe, 10-15 ^^ 10 /x. This species is described as 

 marine, but Schonfeldt, Bacill. Oest. iind Schzv., p. 99, describes a 

 fresh-water form of it. 



In creeks, Ithaca, Ruby, St. Paul. 



6. Perstriatae 



A. With coarse puncta. 46. A'^. lacustris. 



A A. With fine puncta. 47. A^. scutum. 



46. Navicula lacustris A. Sch. A^. D., p. 88, pi. 7, fig. 0. 18/4. 

 Navicula scandanavica (Lag.) CI. S\'n. Nav. Diat., II, p. 48. 



1895. 



Staiironeis scandanavica Lagerst. Boliuls. Diat., p. 4/. 18/6. 



PI. 9, fig. 366. 



Elliptic-lanceolate with apices rostrate, 41-105 ju. long, 14-34 /* 

 wide; striations slightly radiate, punctate, extending nearly to the 

 raphe and leaving a very narrow space along it, but shortened 

 opposite the central nodule, leaving a rectangular hyaline space, 

 12-15 in 10 (x. 



In Devils Lake, N. Dak. 



47. Navicula scutum Schum. in Konigs. Schrift., p. 188, pi. p, 



fig- 45- 1S63. 



PI. 9, fig. 367. 



Elliptical or lanceolate-elliptical, 30-33 /x long, lo-ii^a wide. 

 apices not attenuate; striations slightly radiate, finely punctate, 

 16-18 in 10 ju,, shortened, leaving a broad irregular hyaline space 

 along the raphe, considerably broader opposite the central nodule. 



In creek, Broken Bow ; Fremont, Grand Island ; pond. Pleasant Dale. 



7. Crassinerves 

 A. Apices not capitate. 

 b. Lanceolate. 



c. Apices rounded, about 11 striations in 10 1". 



48. A'', giiatavialciisis. 



