— 139 — 



21 Nitzschia marginulata Grün. 



22 - panduriformis Greg. 



23 Euodia Janischii Grün. 



24 * Frauenfeldii Grün. 



25 Amphora robusta Greg. 

 *26 Amphora 



27 Nitzchia Sigma Sm. var. 



28 Grammatophora oceanica Ehr. 



29 Stauroneis pulchella Sm. 



30 Nitzschia panduriformis Greg. var. 



31 * Formica Hantzch. 



32 Epithemia Westermannii Kg. 



33 Plagiogramma elongatum Grev. 

 34 — 36 Gephyria media Arn. 



37 Euphyllodium spathulatum Shad. 



1 Pleurosigma formosum var. longissima Grün. 

 *2 Pleurosigma 



3 Synedra superba Kg. 



4 Nitzschia latiuscula Grün. 



5 Pleurosigma Balticum Sm. 



6 Navicula robusta Grün. 



7 Pleurosigma formosum Sm. 



8 Synedra formosa Hantzsch. 



9 * fulgens Sm. 



10 Rhoicosigma oceanicum Perag. 



11 Pleurosigma rigidum Sm. 



12 * rhombeum Grün. 



13 = formosum Sm. 



14 * * var. Balearicum Grün. 



15 Navicula Clepsydra Donk. 



16 Stauroneis pulchella Sm. 



17 Pleurosigma Balticum Sm. 



18 * decorum Sm. 



19 Nitzschia latiuscula Grün. 



20 Sceptroneis cuneata Grün. 

 *21 Nitzschia 



22 — 23 Amphiprora lepidoptera Greg. 



24 Navicula maxima Greg. 



25 Climacosphenia monihgera Ehr. 



26 Pleurosigma convexum Grün. 



27 Navicula maxima Greg. 



28 Nitzschia valida Cl. et Grün. 



29 * Gräffei Grün. 



