541 



70. Amphora marginata m. Fig. 114. 66 ° i. L: 0,04 mm., lu. 



ol the valve 0,008 mm., br. of the frustule 0,02 mm., Sti-. 15 in 

 0,01 mm. 



The valve segmeht-shaped, with straighl ventral margin, cm the 

 lalh-r the slriæ are short and indistinct; alun- the dorsal side they 

 form a band. producing a segment-shaped unstriated area 

 on the valve. The connecting zone with a l'ew plications, 

 lainlly and eloselv striated. 



Found only in .i gathering trom Haraldsund Bordo), 

 but occurs frequently in the gathering. 



Tlie form of the frustule as well as of the valve. and 

 the Dumber of the striæ point to A. behringensis Cl. Cl. 

 Syn. II., p. 102, tab. III., ligs. :> I -35), but the connecting zone 

 with plications and the striæ on the ventral side prove that 

 it cannol be identical with the latter species. There is also some pos- 

 sibility of its being related to A. sulcata Breb.? Cl. Cl., 1. c, pp. 112 li:'. . 



Cymbamphora Cl., 1. c. p. 134. 



77. Amphora angusta (Greg.) Cl., A. S., All., tab. XXV., lig. 15. 

 Hare. Between Thorsvig and Kvalvig S tro in o. 



78. A. cymbelloides Grun., A. S., AU., tab. XXVI., ligs. 61—62. 

 Rare. Skaalefjord (Os ter 6). 



MASTOGLOIA Thwaites 1848. Cl. Syn. II., p. 142. 



79. Mastogloia elliptica Ag., V. H. Syn. lab. IV., lig. 19. 

 Rare. Tværaa S y d e r 6 . 



ACHNANTHEÆ Cl., Cl. Syn. IL, p. 163. 

 Rhi)ic<>spht>nia Grun. 18G0. Cl., le., p. 105. 



80. Rhoicosphenia curvata Ktz., V. H. Syn. tab. XXVI., ligs. 1—3. 

 Common. Found in 31 gatherings from Bordo; Oster 6; S trom 6; 



Vaago; Nolso; and Sy der 6. 



R. curvata Kl/, var. subacuta .1. S., A. S. All. tab. CC XIII., ligs. 

 11—13. 



Kalbakfjord (S trom 6); Tværaa Syde ro). 



Cocconeis (Ehr.) CL, CL, Le, p. 168. 



81. Cocconeis Scutellum Ehr., V. H. Syn. lab. XXIX., ligs. 1—3. 

 Very common. Found in 76 gatherings collected trom all the dif- 



ferent islands trom which I have reeeived material. 



C. Scutellum Ehr. var. stauroneiformis W. Sin., V. H., 1. c, figs. 

 10—11. 



Found intermixed with the main species. 



