long, cylindrical lower articulations ; and this much is generally 
sufficient to ascertain the species. But I observe, on some 
specimens, especially those from the South of England, an 
occasional prolongation of the upper angles of the articulation, 
showing a tendency to approach /. corniculata. Still, I have 
never seen a thoroughly intermediate specimen. 
Several exotic species nearly resemble J. rubens in habit, 
differmg chiefly in size and in the comparative length of the 
articulations. 
Fig. 1. JANIA RUBENS, growing on Cladostephus :—of the natural size. 2. A 
branch. 8. Ceramidium. 4. The same, after maceration in acid. 5. Tetra- 
spores. 6. An articulation, from which a transverse slice has been 
removed, showing the internal structure :— all magnified. 
