404 BOTANY OF SOCOTEA. 



2. C. bengalensis, Grunow ; Schmidt Atlas d. Diatom, t. 9, f. 13 ; Kitton 

 in Journ. Linn. Soc. xx. 515, t. 48, f. 6. 



Socotra. Not common. 



Distkib. Whatebevot, Khayenmathy. 



3. C. cistula, Ehr. ; Hemp.; Van Heurck. Synops. 64, t. 2, ff. 12, 13. 



Bacillaria cistula, Ehr. 

 Gomphoncma semidlipticum, Agh. Conspect. 

 G. simplex, Kiitz. Synops. 37, t. 4, f. 23. 



Cocconema cistula, Kiitz. Bacill. 80, t. 6, f. 1 ; Smith Synops. i. 76, t. 23, f. 221 ; Kitton in 

 Journ. Linn. Soc. xx. 515. 



Socotra. Frequent. 

 Distrib. Common everywhere. 



4. C. cymbiformis, Ehr. 



Frustulia cymbiformis, Kiitz. Synops. t. 1, t 19. 



F. coffeceformis, Kiitz. Alg. Dec. ii. No. 11. 



Cymbophora fulva, De Br^bisson. 



Cocconema cymbiforme, Ehr. Infus. t. 19, f. 8; Smith Synops. i. 76, t. 23, f. 220; Schmidt Atlas 



d. Diatom, t. 10, f. 13 ; Van Heurck Synops. 63, t. 2, f. 11 ; Eitton in Journ. Liiin. Soc. 



xx. 515. 



Socotra. Frequent. 



Distrib. A common and widely distributed species. 



Family 2. NAVICULE^, 

 1. NAVICULA. 



Navicula, Bory, 1822. 



1. N. sphserophora, Kiitz. Dec. No. 84; id. Bacill. 95, t. 4, f. 17; Smith 

 Synops. i. 56, t. 17, f. 156; Schmidt Atlas d. Diatom, t. 49, ff. 49-51; Van 

 Heurck Synops. 101, t. 12, ff. 2-3 ; Kitton in Journ. Linn. Soc. xx. 515. 



Anomceoncis sphcerophora, Pfitzer. Bau. u. Entwickl. d. Bacill. 77, t. 3, f. 10. 



Socotra. Rare. 



Distrib. More or less frequent in fresh water everywhere. 



