288 BRITISH SEA- WEEDS. \lViodosjpermece. 



GENUS LXXXIIT. BOSTRYCIIIA, Mont. 



Gen. Char. Frond dull purple, filiform, mucli branched, inar- 

 ticulated, dotted ; traversed by a jointed tube surrounded by one 

 or more concentric layers of oblong, coloured cells, which are 

 gradually shorter towards the circumference ; tlie surface cells 

 quadrate. Fructification of two kinds on distinct individuals : 

 1, "lateral capsules" (ceramidia), Roth.; 2, tetraspores, con- 

 tained in terminal, lanceolate pods. — The name is from a Greek 

 Mord signifying a curl of kah\ or ringlet. — Harvey. 



1. BosTRYCHiA scoRPioiDES, Mout. (Plate XI. fig. 41, 

 branch of the natui'al size ; and small portion of a branch, 

 magnified.) 



Hab. On muddy sea-shores, near high- water mark ; at 

 the estuaries of rivers ; in salt-water ditches and marshes, 

 and even adhering to the roots of fioweriiig-plants. An- 

 nual. Summer. In England and Ireland, but, in so far as 

 we know, not yet observed in Scotland. 



When revising this, and wishing to be better acquainted 

 with this interesting ])lant, of which I had only one specimen 

 from Mrs. Griffiths, a packet arrived from Miss Cutler, con- 

 taining more than a score of fresh undricd specimens, got at 

 the mouth of the river. This was a treat, for which I felt 

 much indebted to that kind and excellent lady, who is so 



