SUPPLEMENT. 125 



with short, spine-like, opposite, or rarely alternate ramuli ; articulations as long as 

 broad ; siliciiles very long, linear-lanceolate, attenuate, densely striate transversely, 

 terminating the principal branches and ramuli. Harv. Phyc. Brit. t. 258. 



Hab. Penobscot Bay, Mr. Hooper, (v. s.) 



I have seen an American specimen collected by Mr. Hooper, which I venture to 

 associate with the Orkney plant to which the above character is given in Phyc. Brit. 

 Perhaps it is a mere form of E. littoralis; though a remarkable one. 



Page 140, add, 



3* EcTOCARPUS amphibius., Harv. ; tufts short, loose, soft, pale olive ; filaments very 

 slender, sub-dichotomous ; ultimate branches alternate, spreading ; articulations two or 

 three times longer than broad ; silicules linear-attenuate, spine-like, mostly sessile, 

 scattered. Harv. Phyc. Brit. t. 183. 



Hab. In fresh (probably brackish ?) water, near New York, Mr. Hooper, (v. s.) 



Tufts 2-3 inches long, very flaccid and slender ; pale brown when fresh, fading to a 

 dull greenish-olive in drying. This is nearly related to E. siliculostis, and may perhaps 

 be regarded as a depauperated variety of that common species, altered by having grown 

 in a less saline medium than usual. In England it occurs in brackish ditches near the 

 coast. The American locality is not particularly specified. 



Part II.— RHODOSPERME^. 



Page 23, add, 



7. CiiONDRiA nidifica ; frond ultrasetaceous, filiform, sparingly and distantly branch- 

 ed ; branches alternate or secund, quite simple or forked, long, cordlike, naked, 

 or emitting at intervals fascicles of forked or multifid fructiferous ramuli ; tetraspores 

 several, near the tips of the ramuli. (Tab. L. B.) 



Hab. Pacific Coast, Dr. Schott. (v. s. in Herb. T. C. D.) 



Fronds 6-8 inches long, as thick as sparrow's quills, cylindrical, inarticulate, sparingly 

 branched in a manner between alternate and dichotomous ; the branches, by frequent 

 non-development of one of the arms of the fork, appearing unilateral. Branches several 

 inches long, quite simple, or once or twice forked ; or bearing a few secondary branches 

 one or more inches long, either quite naked or furnished at intervals of about an inch 

 with tufts of short, fructiferous ramuli. These latter are about quarter-inch long, 

 as thick as hog's bristle, densely tufted, and simple or sub-divided. In the specimen 

 examined some of them bear tetraspores. A transverse slice of the inarticulate frond 



