
 
		2927. ƒ   2. 
 LYNGBYA  ferruginea.  
 Rusty Lyngbya. 
 Gen. Char.  Fruit terminal.  Perianth  none except  
 the  convolute  involucral  leaves.  Calyptra  immersed  
 in the involucre. 
 Spec.  Char.  Filaments  slender,  flaccid,  forming  a  
 lax  stratum  of  a  verdigris-green  colour,  which  
 gradually changes to a pale chestnut. 
 Syn.  Lyngbya  ferruginea.  Agardh  Syst.  Alg.  73.  
 Harv. in Hook. Eng. FI. v.  5. pt.  1.  370.  Harv.  
 Man.  160. 
 Lyngbya subsalsa.  Carm. MSS. 
 O n  mud occasionally  covered  by  the tide.  Appin,  Capt.  
 Carmichael;  Sussex coast, W. Borrer, Esq.;  Holyhead and  
 coast near Dolgelley, J.  Ralfs, Esq., to whom we are indebted  
 for our specimens of this and the two preceding species. 
 Forming  a  loose  thin  stratum  on mud.  Threads an inch  
 or more long, flexuous, but  not  twisted, of a pale  verdigris-  
 green  which  changes  in  the  older portions to yellow-brown.  
 Rings apparently distant  or  approximate  according  to  their  
 degree of development, at length  bursting in masses from the  
 tubes which  are left more or less empty. 
 Specimens received from M. Lenormand gathered at Caen  
 have far more slender  threads  than  those  of Mr. Ralfs,  and  
 belong to a distinct species.—M. J. B.