CONTENTS. 



XI. 



Genus 8. 

 Genus 9. 

 Genus 10. 

 Genus 1 1. 

 Genus 12. 

 Genus 13. 

 Genus 14. 

 Genus 15. 



Genus 16. 

 Genus 1 7. 



Genus 18. 



Genus 19. 



Genus 20. 

 Genus 21. 

 Genus 22. 



Genus 23 

 Genus 24. 

 Genus 25. 



Genus 26. 



Genus 27. 



Genus 28. 



Genus 29. 



Genus 30. 



Genus 31. 



Page 



Rhoiconeis Grun., 1863 .... 238 

 Cymatoneis Cleve, 1894 . . . 238 



COLLETONEMA (BREB., 1849), H. VAN HEURCK, 1S85 . 238 



Van Heurckia Breb., 1868, Char. Em. . . 239 



Stenoneis Cleve, 1894 . . . .241 



Cistula Cleve, 1894 , . .241 



Amphipleura Ktz., 1844 .... 242 

 Reicheltia H. Van Heurck, 1895 . . . 243 



Gomphopleura Reichelt, 1894. 



Brebissonia Grun., i860 .... 244 

 Rouxia J. Brun. & Herib., 1893 . . 244 



Berkeleva (Grev., 1827), H. Van Heurck, T885 . 245 



k.iphidoglcea Ktz., 1844= Berkeleya in a globular frond, frustules 

 arranged in fusiform rows. 



Scoliopleura Grun, i860 .... 246 



Scoliotropis Cleve, 1894. 



Toxonidea Donkin, 1858 .... 247 

 Donkinia Ralfs., i860 .... 248 

 Pleurosigma W. Sm., 1853 .... 249 



Pleurosigma W. Sm. partim stria? decussating. 

 Gyrosigma Hassall, 1845 strire rectangular. 



Rhoicosigma Grun., 1867, Em. Perag., 1891 . . 260 



Amphiprora (Ehr.), 1843, Cleve, 1891 . . 261 



Tropidoneis Cleve, 1891 . . . 263 



1. Orthotropis Cleve, 1S91. . . . 263 



2. Plagiotropis Pfitzer, 187 1 . . . 264 



3. Amphoropsis Grun., 1883 . . . 266 



Auricula Castr., 1873 .... 266 



Tribe III. Gomphono-me/E . . . 268 



Gomphonema Ag., 1824, Char. Em. . . . 268 



Sphenella Ktz., 1844 frustules free. 

 Gomphonema Ag., 1824 frustules stipitate. 

 Sphenosira Ehr. , 1843 frustules united in filaments. 

 Gomphonella Rab. , 1853 frustules enclosed in an amorphous gelly. 

 Gomphoneis Cleve, 1894 valves furnished with costte alternating 

 with beads. 



Rhoicosphenia Grun., i860 

 Tribe IV. Achnanthe^ 



ACHNANTHIDIUM (KTZ.) GRUN., l88o . 



Achnanthes Bory., 1822 .... 



Achnanthidium Ktz., 1844 frustules united in an amorphous gelly 



or free. 

 Monogramma Ehr., 1843 frustules with a transverse line on one of 



the valves. 

 Cymbosira Ktz., 1844 frustules united, end to end, in rows. 



Tribe V. Cocconeide,e 

 Orthoneis Grjn., 1868, Em. Grun., 1880 



275 

 276 



276 

 277 



283 

 283 



