Puate CXX. B. 
CALLITHAMNION ROTHII, Zynge. 
CatuitHaMNion Roth; widely spreading, densely tufted; filaments very 
slender, short, erect, dichotomous or irregularly branched ; branches 
long, straight, appressed ; articulations twice as long as broad ; tetra- 
spores clustered, borne on short, subterminal, corymbose ramuli. 
CALLITHAMNION Roth, Lyngb. Hyd. Dan. p. 129. t. 41. Ag. Syst. Alg. 
vol. ii. p. 185. Harv. in Hook. Br. Fl. vol. 0. p. 347. Harv. Man. p. 116. 
Wyatt, Alg. Danm. no, 188. Endl. 3rd Suppl.p.34. Kiitz. Phyc. Gen. p. 471. 
Creramivum Rothii, Berk. Gl. Br. Alg. t. 20. 
TRENTEPOHLIA Rothi, Harv. in Mack. Fl. Hib. part 3. p. 218. 
Conrerva Rothii, Linn. Syst. Nat. vol. vi. p. 1806. Dillw. Conf. t. 73. 
£. Bot. t.1702. Jurg. Alg. Dee. no. 10. 
ConFerva violacea, Roth. Cat. Bot. vol.i. p.190.t.4.f.1. Fl. Germ. v. iii. 
part 1. p. 525. 
8. purpurea; filaments very minute, forming continuous velvetty patches, 
slightly branched. 
CALLITHAMNION purpureum, Harv. Man. p. 116. 
TRENTEPOHLIA purpurea, 4g. Syst. p.36. Harv. in Hook. Br. Fl. vol. ii. 
p- 382. Harv. in Mack. Fl. Hib. part 3. p. 218. 
Byssvs purpurea, H. Bot. t. 192. 
ConFERvaA purpurea, Dillw. t. 43. 
Has. Spreading over the surface of rocks, about half-tide level. 8. on 
maritime rocks, within the influence of the spray, but beyond the 
reach of ordinary tides. Perennial. Winter. 
Grocer. Distr. Atlantic shores of Europe. Baltic Sea. East coast of North 
America. 
Descr. Filaments from a line to half an inch in height, very slender, densely 
packed together in extensive velvetty patches, of a deep red or purplish 
red colour. Branches few, simple, and very erect, the lowest longest, gene- 
rally bare of ramuli. Tetraspores two to four, or frequently three together, 
on short pedicels, growing from the uppermost joints of the branches. 
Joints twice as long as broad. Substance membranaceous, more or less per- 
fectly adhering to paper. 
A smaller and more slender plant than the preceding, with 
shorter joints, and well characterized by the difference in fructi- 
fication. I have ventured, I trust not without sufficient warrant, 
to unite to C. Rothii the old Conferva or Byssus purpurea, which 
I have long regarded as a stunted form, whose characters depend 
on the situation in which it is found growing. In this opinion 
I am supported by Mr. Ralfs, an accurate and close observer, who 
has had the best opportunities of mvestigating the subject. 
Fig. B. CaLLitHaMNtIon Rorutt:—of the natural size. 2. Portion of a filament. 
3. Apex of a branch in fruit. 4. Section of a branch with clusters of 
tetraspores :—all more or less magnified. 
