16 36 Proceedings of the Royal Irish Academy. 



Eunotia major (W. Sin.) Eabenh.— C, L; W, 122m long; D, 152m long. 

 var. bidens V. H. — SL. 

 **minor (Kiitz.) Eabenh. — "W, 31 x 6m, valve-view. 

 pectinalis (Dillw.) Eabenh.— C, K, Ac, M, W; S.W. of D, 95 x 31m, 

 girdle- view. 



var. undulata Ralfs. — D, 60-65 x 5-5"3m- 

 var. Soleirolii Kiitz. — W. 

 var. ventricosa Gran. — CP. 

 var. strieta Eabenh. — D, 40m long, 

 f. elongata V. H.— B, W. 

 f. curta V. H. — D ; W, 25 x 7m valve-view, 

 praerupta Ehrenb.— L; W, 35 x 7 W ; C, 55 x 95m. 



var. bidens (Ehrenb.) Gran. — ; D, 43m long, 

 var. inflata Grim. — L. 

 var. curta V. H. — L ; W, 34 x 6'3m- 

 robusta Ealfs var. tetraodon V. H. — M. 

 Ceratoneis Arcus Ehrenb.) Kiitz. — C, L; CP, 40-45 x 5-6m, a constantly 

 short form; W, 36'6 x 4/x. 



Tribe Synedreae. 

 Synedra Acus Kiitz.) Gran. — C, W ; L, 132 x 66/x, valve-view; I, B, D, 

 Croaghmore chffs, K. 



var. delicatissima W. Sm. — W ; C, 88m long; CP, 112 x 4/i, 

 valve- view. 

 amphicephala Kiitz. — LG, L ; W, 35 x 3 - 2m. 

 famelica Kiitz.— C, L, I, B, D, LG, CP. 



pulchella Kiitz. — C, W ; L, 53-5 x 6m, valve-view ; CP, 114-132m long, 

 7'2m broad at middle, 4 - 9m at apices. 



var. Smithii Ealfs. — VL ; D, 121 x 5m, valve-view. 

 f. major V. H.— C, 133-136 x 7-7'6m- 

 radians (Kiitz.) Gran.— VL, C, CI, M, W, B ; L, 61 x 1-6m, valve-view. 

 Ulna (Mtzsch.) Ehrenb.— -L, C, K, I, VL, CI, D ; W, average length 

 220/i, up to 260m ; CP, Croaghmore cliffs. 



var. amphirhynchus (Ehrenb.) V.H. — C ; W, 164 x 5m, valve- 

 view. 

 var. splendens (Kiitz.) Grun. — W. 

 var. lanceolata (Kiitz.) V.H. — W. 



var. dauica (Kiitz.) V.H. — C, 244 x 5/n, valve- view ; W, a broad 

 form 188 x 7"5-8m, valve-view; L. 

 Vaucheriae Kutz. — C, M. 



