14 ARKIV FÖR BOTANIK, BAND 14. NIO 9. 



Foss.: Kk. Knjäsha, mixed with the typical form. 

 I think these two forms may be distinguished from one 

 another, though Cleve has united them. 



Diploneis decipiens n. sp. — Icon. nost. PL 1, f. 11. 



Valve elongated elliptical, 30 — 35 [j. in length, 12 — 18 |Ji. 

 in breadth. Costae 9 in 10 [x, alternating with coarsely, but 

 obscurely pearled striae. Furrows close to the horns, slightly 

 widened round the central nodule, that is small. 



Foss. {mar.): Kk. Knjäsha, not rare; Koudajärvenpää. 



This Diploneis, occurring in a purely marine society, is 

 certainly closely connected with Dipl. elliptica, from which 

 it is difficult to distinguish by any other character than the 

 obsolete punctuation. I first thought it possibly identic with 

 a Diplo7ieis, figured by Mr 0strup in Danske D. Tab. 1, f. 17 

 (p. 24) and determined to D. horealis Grun. But the striation 

 of the latter being that of D. Smithii, the two forms must 

 be different. The form of Mr 0strup is also rather different 

 from the large and typical D. horealis Grun., that is present 

 in some Knjäsha-samples. 



Diploneis decipiens n. sp. var. parallela n. var. — PL 

 1, f. 12. 



Differs from the main form by a more delicate central 

 nodule and perfectly parallel furrows. 



Foss.: Kk. Knjäsha, sparingly among the type. 



Diploneis Mauleri Brun. D. Esp. nouv. Tab. 15, f. 7. 

 — Cleve, Syn. Nav. D. I, p. 98. 



Foss.: Ka. Viborg-dep. (Cleve 1894), Nyl. Hinders- 

 mossen, Kyrkslätt (Deposits from the Ancylus-eT^och). 



Distr. {fresh or slightly brackish w.): Vettern, Gulf of 

 Bothnia, Leman, Rammer moor, Sahara. (Foss.) Baltic de- 

 posits from the Ancylus-e])oc\\. 



Naviculae Orthostichae Cl. 



Navicula halophila Grun. var. subcapitata 0str. Danske 

 D., p. 29, Tab. 1, f. 22. 



