XIV. 



CONTENTS. 



B. More than two false septa. 



a. Fossil or fresh water forms. 



Genus 68. Tabellaria Ehr., 1839 .... 

 Genus 69. Tetracyclus (Ralfs, 1843) Grun, 1862 



Salacia Pant., 1889 valves elliptic, lanceolate. 



Goniphogramma Braun, 1852 valves elliptic, frustules united by 

 twos or threes. 



Genus 70. Stylobiblium Ehr., 1845 



b. Marine forms. 



Genus 71. Rhabdonema Ktz., 1844 .... 

 Genus 72. Climacosira Grun., 1862 .... 

 Genus 73. Striatella Ag., 1832 .... 



Hyalosira Ktz., 1844 septa appearing alternately interrupted at 



their apex. 

 Tessella Ehr., 1838 septa interrupted in the middle of their length. 



Genus 74. Lamella Brun., 1894 .... 



Cohort III. Surirellineaz .... 

 Tribe XVI. Surirelle^e 

 Genus 75. Podocystis Ktz., 1844, Char. Em. 



Euphyllodium Shadb. , 1853 costas anastomosing. 



Genus 76. Hydro-silicon Brun., 1891 



Genus 77. Cymatofleura W. Sm., 185 i 



Genus 78. Surirella Turpin, 1827 .... 



Stenopterobia Breb. in litt. frustules narrow, elongated, sigmoid. 

 Calodiscus Rab., 1853 valves orbicular or sub-orbicular, without 



median line. 

 Plagiodiscus Grun. and Eul., 1868 valves reniform, with radiant 



costae (anomalous forms). 



Campylodiscus Ehr., 1841 



Cohort IV. Nitzschiinece . 



Tribe XVII. Nitzschieve 



Hantzschia Grun., 1877 . 



Nitzschia (Hassall, 1845 5 ^ M - Smith) Char. Em., 

 Grun., 1880 . . . . 



Bacillaria Gmel. , 1788 frustules in tablets or in oblique rows. 

 Tryblionella W. Sm., 1853 valves undulate, septate, with carina 



indistinctly punctate. 

 Pritchardia Rab., 1863 carina with puncta prolonged into costas, 



striae alternately prolonged. 

 Perrya Kitton, 1874 carinal dots prolonged into long interrupted 



lines. 

 Grunowia Rab., 1864 dots prolonged into transverse or dimidiate 



costas. 

 Nitzschiella Rab., 1864 valves with apices very attenuated (flexed). 

 Homoeocladia Ag., 1827 frustules enclosed in mucous tubes. 



Genus 82. Gomphonitzschia Grun., i8c8 



Tribe XVIII. Cylindrothece^e 

 Genus 83. Cylindrotheca Rab., 1859 



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366 

 366 

 .168 



Genus 79. 



Genus 80. 

 Genus 81. 



375 

 380 

 380 

 380 



382 



408 



409 

 409 



