16 34 Proceedings of the Royal Irish Academy. 



G-omphonema graeile Ehrenb. — C. 



var. dichotomum (Kutz.) Y.H.— B. ¥, D ; Or, 44 x 6\5 U , 

 valve- view ; Croaghniore cliffs, K 

 intricatum Kiitz. — C, 1. B, TV. LG. 



var. Vibrio 'Ehrenb.. Y.H.— B ; D. LG-. 

 var. pumila Grun. — B. 

 ""montanam Schumann var. subelavatum Grun. — C. 



var. eommutatum Gran. — C, 41^ long, 9^ greatest breadtb in 

 valve- view ; TV, 44 x S - 4u, also in another place 44 x 9oju. 

 olivaceum (Lyngb.) Kiitz.— C. L : I. VI.. D. GP. 

 parvulum Kiitz. — C, LG. M. 

 Rhoieosphaenia curvata (Kiitz. Grun. — L, on Cladophora crispata; C, on 

 vescens smdBhuocionium hieroglyphieum. 



Tribe Achnantheae. 



Achnantbidium flexellum Breb. — TV : C. 31-5 x 15*8/i, valve-view, 35-38 x 



146-1 6u. 

 Ac'nnanthes exilis Kii:z. — C : TV. 24n long, average size ; S, IT, L, I, B, D, LG : 

 CP. l6-20> long ; Gr ; K, 20 u long, 

 linearis iW. Sra. Grun. — G L. 

 biasolettiana Grun.— C, IT, B, L W, Cr. 

 *minutissima Kiitz.— C. 22-2+ x 45/*, valve-view, 

 microcephala Kiitz. Gran.— C, CP. 



Tribe Cocconeideae. 



Coeconeis Pediculus Ebreub. — G. IT. D. TV. L. on Cladophora crispata. 

 Placentula Ehrenb.— G, 18-36 x 125-23^; L : I, D. TV. 

 var. lrneata V. H. — C. 



Division II. PSEUDEAPHIDIEAE. 

 Tribe Epithemieae. 



Epithemia Argus (Ehrenb. - ) Kiitz. — C, 41-44 x 10u valve-view, girdle-view 



- L. B. 



var. amphicephala Grun. — C, 416 x 91^ average; TV. 

 turgida (Ehrenb. Kiitz.— C, average size 70-5-92-5/I long. 16o-17u 

 broad, valve-view ; IT, L. TV. 



var. "Westermanui Kiitz — L. TV. 

 gibberula Ehrenb.) Kiitz. var. producta Grun. — Cr; D, 26-34« long: TI 

 length 375/u : C, length 36-37u, in another place 30/u long : B, I, CI. 



