340 Dr. Greville's Account of a Collection of 



At first sight it has a near resemblance to some states of 

 Spluerococciis bijidiis, but the discovery of the fructification proved 

 it to belong to a different genus. In texture and delicacy as 

 well as fructification it is nearly allied to Dclcssevin punctata, 

 but the constant dichotomous, linear, smaller frond, and very 

 divaricated segments, keep it sufficiently apart. 



The specimens in the present collection arc smaller and not 

 fertile ; yet I think there cannot be a doubt of their being the 

 same species. 



( Facoidcce.) 



Genus 19- Scytosiphon. 

 1. S. fœniculaceus. Lyngb. Tent. Hydropliijt. Dan. p. 63. t. 14. 

 Ag. Syst. Alg. p. 258. Fucus subtilis. Turn. Hist. Fuc. 

 t. 234. 



Genus 20. IIaliseris. 



1. H. polypodioides. Ag. Syat. Alg. p. 262. Fucus membrana- 

 ceus. Stackh. Ner. Brit. p. 13. t. 6. Turn. Hint. Fuc. 

 /.87. 



Genus 21. Zonaiua. 



1. Z. rubra, fronde reniformi, plana, subintegerrimâ, fragili, ni- 

 tidâ, rubra, lineis minutissimis longitudinaliter densissimc 

 notatâ. Tab. III. f. 3. 



In the sea, about the roots oï Zostera marina. 



Frond dull pinkish red, half an inch to one inch in breadth, 

 roundish reniform, nearly plain, the margin entire or 

 very slightly lobed ; surface glabrous, somewhat glisten- 

 ing, densely reticulated, the reticulations minute, arranged 

 in close parallel convex longitudinal lines, scarcely per- 

 ceptible to the naked eye. There are also a few transverse 



corruo;ations. 



