habit than by any precise character; that species growing in glo- 
bose masses, which are unattached, and lie, subject to the drifting 
of the waves, on the sea-bottom. 
Mastophora licheniformis, Dene., which Kiitzing refers to the 
plant now figured, is very different in many ways, generically 
and specifically. 
Fig. 1. MELOBESIA LICHENOIDES; growing on a piece of rock :—the natural 
size. 2. Portion of a frond :—magnified. 3. Vertical section through an 
(empty) ceramidium :—magnified. 4. Portion of the cellular substance :— 
highly magnified. 
