CELLULOSE. ALGACE.^. 115 



528. ZYGNEMA, Ag. ZYGNEMA. 



612. Z. nitidum, Ag. Smooth Zygnema. In ditches. common. 



613. Z. deciminum, Ag. Crossed Zygnema, In pools. common* 



614. Z. quininum, Ag. Angled Zygnema. In pools. common. 



529. SPH^EROPLEA, ^. SPH^EROPLEA. 



615. S. crispa, Berk. Curled Sphceroplea. Cork harbour: Dr. 

 JF. .ST. Harvey. rather rare. 



Tribe XVIII. Siphonece. 

 530. CODIUM, Stack. CODIUM. 



616. C. tomentosum, Stack. Downy Codium. On rocks common. 



531. BRYOPSIS, Lamour. BRYOPSIS. 



617. B. plumosa, Ag. Feathery Bryopsis. Cork harbour: Dr. 

 Harvey. common. 



532. VAUCHERIA, De Cand. VAUCHERIA. 



618. V. dichotoma, Ag. Dichotomous Vaucheria. Cork. common. 



619. V. marina, Lyngb. Sea Vaucheria. Youghal: Miss Ball. 

 very rare. 



620. V. velutina, Ag. Velvety Vaucheria. Muddy shores : Dr. 

 Harvey. rare. 



621. V. Dilwynii, Ag. Dilwyn's Vaucheria. County of Cork: 

 Dr. W. H. Harvey. common. 



622. V. terrestris, D.C. Ground Vaucheria. On the ground.-*- 

 common. 



623. V. ccespitosa, Ag. Tufted Vaucheria. By pools very common. 



533. BOTRYDIUM, Wallr. BOTRYDIUM. 



624. B. granulatum, Grev. Granulate Botrydium. In Dodges- 

 glen, on the dried mud at the edge of the pond : Mr. D. Murray. 

 very rare. 



Tribe XIX. Oscillatorice. 

 534. RIVULARIA, Roth. RIVULARIA. 



625. R. pisum, Ag. Pea Rivularia. In the county of Cork : 

 Dr. W. H. Harvey. Who has alone noticed it. very rare. 



626. R. calcarea, Sm. Calcareous Rivularia. In alpine streams. 

 rare. 



627. R. plicata, Carm. Plaited Rivularia. Near Youghal: Miss 

 Ball. rare. 



628. R. ara, Roth. Dark Rivularia. On rocks in the sea. 

 common. 



629. R. nitida, Ag. Shining Rivularia. In the county of Cork: 

 Dr. W. H. Harvey. rather rare. 



535. STIGONEMA, Ag. STIGONEMA. 



630. S. atrovirens, Ag. Tufted Stigonema. In the county of 

 Cork : Dr. W. H. Harvey. very common. 



P 



